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  Subjects -> COMPUTER SCIENCE (Total: 1985 journals)
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COMPUTER SCIENCE (1153 journals)                  1 2 3 4 5 6 | Last

Showing 1 - 200 of 872 Journals sorted alphabetically
3D Printing and Additive Manufacturing     Full-text available via subscription   (Followers: 12)
Abakós     Open Access   (Followers: 3)
Academy of Information and Management Sciences Journal     Full-text available via subscription   (Followers: 67)
ACM Computing Surveys     Hybrid Journal   (Followers: 23)
ACM Journal on Computing and Cultural Heritage     Hybrid Journal   (Followers: 8)
ACM Journal on Emerging Technologies in Computing Systems     Hybrid Journal   (Followers: 13)
ACM Transactions on Accessible Computing (TACCESS)     Hybrid Journal   (Followers: 4)
ACM Transactions on Algorithms (TALG)     Hybrid Journal   (Followers: 16)
ACM Transactions on Applied Perception (TAP)     Hybrid Journal   (Followers: 6)
ACM Transactions on Architecture and Code Optimization (TACO)     Hybrid Journal   (Followers: 9)
ACM Transactions on Autonomous and Adaptive Systems (TAAS)     Hybrid Journal   (Followers: 7)
ACM Transactions on Computation Theory (TOCT)     Hybrid Journal   (Followers: 11)
ACM Transactions on Computational Logic (TOCL)     Hybrid Journal   (Followers: 4)
ACM Transactions on Computer Systems (TOCS)     Hybrid Journal   (Followers: 18)
ACM Transactions on Computer-Human Interaction     Hybrid Journal   (Followers: 12)
ACM Transactions on Computing Education (TOCE)     Hybrid Journal   (Followers: 3)
ACM Transactions on Design Automation of Electronic Systems (TODAES)     Hybrid Journal   (Followers: 1)
ACM Transactions on Economics and Computation     Hybrid Journal  
ACM Transactions on Embedded Computing Systems (TECS)     Hybrid Journal   (Followers: 4)
ACM Transactions on Information Systems (TOIS)     Hybrid Journal   (Followers: 20)
ACM Transactions on Intelligent Systems and Technology (TIST)     Hybrid Journal   (Followers: 9)
ACM Transactions on Interactive Intelligent Systems (TiiS)     Hybrid Journal   (Followers: 4)
ACM Transactions on Multimedia Computing, Communications, and Applications (TOMCCAP)     Hybrid Journal   (Followers: 10)
ACM Transactions on Reconfigurable Technology and Systems (TRETS)     Hybrid Journal   (Followers: 7)
ACM Transactions on Sensor Networks (TOSN)     Hybrid Journal   (Followers: 8)
ACM Transactions on Speech and Language Processing (TSLP)     Hybrid Journal   (Followers: 11)
ACM Transactions on Storage     Hybrid Journal  
ACS Applied Materials & Interfaces     Full-text available via subscription   (Followers: 21)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 3)
Acta Universitatis Cibiniensis. Technical Series     Open Access  
Ad Hoc Networks     Hybrid Journal   (Followers: 11)
Adaptive Behavior     Hybrid Journal   (Followers: 11)
Advanced Engineering Materials     Hybrid Journal   (Followers: 26)
Advanced Science Letters     Full-text available via subscription   (Followers: 7)
Advances in Adaptive Data Analysis     Hybrid Journal   (Followers: 8)
Advances in Artificial Intelligence     Open Access   (Followers: 15)
Advances in Artificial Neural Systems     Open Access   (Followers: 4)
Advances in Calculus of Variations     Hybrid Journal   (Followers: 2)
Advances in Catalysis     Full-text available via subscription   (Followers: 5)
Advances in Computational Mathematics     Hybrid Journal   (Followers: 15)
Advances in Computer Science : an International Journal     Open Access   (Followers: 13)
Advances in Computing     Open Access   (Followers: 3)
Advances in Data Analysis and Classification     Hybrid Journal   (Followers: 53)
Advances in Engineering Software     Hybrid Journal   (Followers: 25)
Advances in Geosciences (ADGEO)     Open Access   (Followers: 10)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 25)
Advances in Human-Computer Interaction     Open Access   (Followers: 19)
Advances in Materials Sciences     Open Access   (Followers: 16)
Advances in Operations Research     Open Access   (Followers: 11)
Advances in Parallel Computing     Full-text available via subscription   (Followers: 7)
Advances in Porous Media     Full-text available via subscription   (Followers: 4)
Advances in Remote Sensing     Open Access   (Followers: 37)
Advances in Science and Research (ASR)     Open Access   (Followers: 6)
Advances in Technology Innovation     Open Access  
AEU - International Journal of Electronics and Communications     Hybrid Journal   (Followers: 8)
African Journal of Information and Communication     Open Access   (Followers: 6)
African Journal of Mathematics and Computer Science Research     Open Access   (Followers: 4)
Air, Soil & Water Research     Open Access   (Followers: 7)
AIS Transactions on Human-Computer Interaction     Open Access   (Followers: 6)
Algebras and Representation Theory     Hybrid Journal   (Followers: 1)
Algorithms     Open Access   (Followers: 10)
American Journal of Computational and Applied Mathematics     Open Access   (Followers: 3)
American Journal of Computational Mathematics     Open Access   (Followers: 4)
American Journal of Information Systems     Open Access   (Followers: 6)
American Journal of Sensor Technology     Open Access   (Followers: 2)
Anais da Academia Brasileira de Ciências     Open Access   (Followers: 2)
Analog Integrated Circuits and Signal Processing     Hybrid Journal   (Followers: 5)
Analysis in Theory and Applications     Hybrid Journal  
Animation Practice, Process & Production     Hybrid Journal   (Followers: 5)
Annals of Combinatorics     Hybrid Journal   (Followers: 3)
Annals of Data Science     Hybrid Journal   (Followers: 8)
Annals of Mathematics and Artificial Intelligence     Hybrid Journal   (Followers: 6)
Annals of Pure and Applied Logic     Open Access   (Followers: 2)
Annals of Software Engineering     Hybrid Journal   (Followers: 12)
Annual Reviews in Control     Hybrid Journal   (Followers: 6)
Anuario Americanista Europeo     Open Access  
Applicable Algebra in Engineering, Communication and Computing     Hybrid Journal   (Followers: 2)
Applied and Computational Harmonic Analysis     Full-text available via subscription   (Followers: 2)
Applied Artificial Intelligence: An International Journal     Hybrid Journal   (Followers: 14)
Applied Categorical Structures     Hybrid Journal   (Followers: 2)
Applied Clinical Informatics     Hybrid Journal   (Followers: 1)
Applied Computational Intelligence and Soft Computing     Open Access   (Followers: 12)
Applied Computer Systems     Open Access   (Followers: 1)
Applied Informatics     Open Access  
Applied Mathematics and Computation     Hybrid Journal   (Followers: 32)
Applied Medical Informatics     Open Access   (Followers: 10)
Applied Numerical Mathematics     Hybrid Journal   (Followers: 5)
Applied Soft Computing     Hybrid Journal   (Followers: 16)
Applied Spatial Analysis and Policy     Hybrid Journal   (Followers: 4)
Architectural Theory Review     Hybrid Journal   (Followers: 3)
Archive of Applied Mechanics     Hybrid Journal   (Followers: 4)
Archive of Numerical Software     Open Access  
Archives and Museum Informatics     Hybrid Journal   (Followers: 120)
Archives of Computational Methods in Engineering     Hybrid Journal   (Followers: 4)
Artifact     Hybrid Journal   (Followers: 2)
Artificial Life     Hybrid Journal   (Followers: 5)
Asia Pacific Journal on Computational Engineering     Open Access  
Asia-Pacific Journal of Information Technology and Multimedia     Open Access   (Followers: 1)
Asian Journal of Computer Science and Information Technology     Open Access  
Asian Journal of Control     Hybrid Journal  
Assembly Automation     Hybrid Journal   (Followers: 2)
at - Automatisierungstechnik     Hybrid Journal   (Followers: 1)
Australian Educational Computing     Open Access  
Automatic Control and Computer Sciences     Hybrid Journal   (Followers: 3)
Automatic Documentation and Mathematical Linguistics     Hybrid Journal   (Followers: 5)
Automatica     Hybrid Journal   (Followers: 9)
Automation in Construction     Hybrid Journal   (Followers: 6)
Autonomous Mental Development, IEEE Transactions on     Hybrid Journal   (Followers: 8)
Basin Research     Hybrid Journal   (Followers: 4)
Behaviour & Information Technology     Hybrid Journal   (Followers: 52)
Bioinformatics     Hybrid Journal   (Followers: 294)
Biomedical Engineering     Hybrid Journal   (Followers: 16)
Biomedical Engineering and Computational Biology     Open Access   (Followers: 13)
Biomedical Engineering, IEEE Reviews in     Full-text available via subscription   (Followers: 17)
Biomedical Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 32)
Briefings in Bioinformatics     Hybrid Journal   (Followers: 45)
British Journal of Educational Technology     Hybrid Journal   (Followers: 120)
Broadcasting, IEEE Transactions on     Hybrid Journal   (Followers: 10)
c't Magazin fuer Computertechnik     Full-text available via subscription   (Followers: 2)
CALCOLO     Hybrid Journal  
Calphad     Hybrid Journal  
Canadian Journal of Electrical and Computer Engineering     Full-text available via subscription   (Followers: 14)
Catalysis in Industry     Hybrid Journal   (Followers: 1)
CEAS Space Journal     Hybrid Journal  
Cell Communication and Signaling     Open Access   (Followers: 1)
Central European Journal of Computer Science     Hybrid Journal   (Followers: 5)
CERN IdeaSquare Journal of Experimental Innovation     Open Access  
Chaos, Solitons & Fractals     Hybrid Journal   (Followers: 3)
Chemometrics and Intelligent Laboratory Systems     Hybrid Journal   (Followers: 15)
ChemSusChem     Hybrid Journal   (Followers: 7)
China Communications     Full-text available via subscription   (Followers: 7)
Chinese Journal of Catalysis     Full-text available via subscription   (Followers: 2)
CIN Computers Informatics Nursing     Full-text available via subscription   (Followers: 12)
Circuits and Systems     Open Access   (Followers: 16)
Clean Air Journal     Full-text available via subscription   (Followers: 2)
CLEI Electronic Journal     Open Access  
Clin-Alert     Hybrid Journal   (Followers: 1)
Cluster Computing     Hybrid Journal   (Followers: 1)
Cognitive Computation     Hybrid Journal   (Followers: 4)
COMBINATORICA     Hybrid Journal  
Combustion Theory and Modelling     Hybrid Journal   (Followers: 13)
Communication Methods and Measures     Hybrid Journal   (Followers: 11)
Communication Theory     Hybrid Journal   (Followers: 19)
Communications Engineer     Hybrid Journal   (Followers: 1)
Communications in Algebra     Hybrid Journal   (Followers: 3)
Communications in Partial Differential Equations     Hybrid Journal   (Followers: 3)
Communications of the ACM     Full-text available via subscription   (Followers: 53)
Communications of the Association for Information Systems     Open Access   (Followers: 18)
COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering     Hybrid Journal   (Followers: 3)
Complex & Intelligent Systems     Open Access  
Complex Adaptive Systems Modeling     Open Access  
Complex Analysis and Operator Theory     Hybrid Journal   (Followers: 2)
Complexity     Hybrid Journal   (Followers: 6)
Complexus     Full-text available via subscription  
Composite Materials Series     Full-text available via subscription   (Followers: 9)
Computación y Sistemas     Open Access  
Computation     Open Access  
Computational and Applied Mathematics     Hybrid Journal   (Followers: 2)
Computational and Mathematical Methods in Medicine     Open Access   (Followers: 2)
Computational and Mathematical Organization Theory     Hybrid Journal   (Followers: 2)
Computational and Structural Biotechnology Journal     Open Access   (Followers: 2)
Computational and Theoretical Chemistry     Hybrid Journal   (Followers: 9)
Computational Astrophysics and Cosmology     Open Access   (Followers: 1)
Computational Biology and Chemistry     Hybrid Journal   (Followers: 12)
Computational Chemistry     Open Access   (Followers: 2)
Computational Cognitive Science     Open Access   (Followers: 1)
Computational Complexity     Hybrid Journal   (Followers: 4)
Computational Condensed Matter     Open Access  
Computational Ecology and Software     Open Access   (Followers: 8)
Computational Economics     Hybrid Journal   (Followers: 9)
Computational Geosciences     Hybrid Journal   (Followers: 13)
Computational Linguistics     Open Access   (Followers: 23)
Computational Management Science     Hybrid Journal  
Computational Mathematics and Modeling     Hybrid Journal   (Followers: 8)
Computational Mechanics     Hybrid Journal   (Followers: 4)
Computational Methods and Function Theory     Hybrid Journal  
Computational Molecular Bioscience     Open Access   (Followers: 2)
Computational Optimization and Applications     Hybrid Journal   (Followers: 7)
Computational Particle Mechanics     Hybrid Journal   (Followers: 1)
Computational Research     Open Access   (Followers: 1)
Computational Science and Discovery     Full-text available via subscription   (Followers: 2)
Computational Science and Techniques     Open Access  
Computational Statistics     Hybrid Journal   (Followers: 13)
Computational Statistics & Data Analysis     Hybrid Journal   (Followers: 28)
Computer     Full-text available via subscription   (Followers: 83)
Computer Aided Surgery     Hybrid Journal   (Followers: 3)
Computer Applications in Engineering Education     Hybrid Journal   (Followers: 6)
Computer Communications     Hybrid Journal   (Followers: 10)
Computer Engineering and Applications Journal     Open Access   (Followers: 5)
Computer Journal     Hybrid Journal   (Followers: 7)
Computer Methods in Applied Mechanics and Engineering     Hybrid Journal   (Followers: 22)
Computer Methods in Biomechanics and Biomedical Engineering     Hybrid Journal   (Followers: 10)
Computer Methods in the Geosciences     Full-text available via subscription   (Followers: 1)
Computer Music Journal     Hybrid Journal   (Followers: 14)
Computer Physics Communications     Hybrid Journal   (Followers: 6)
Computer Science - Research and Development     Hybrid Journal   (Followers: 7)
Computer Science and Engineering     Open Access   (Followers: 17)
Computer Science and Information Technology     Open Access   (Followers: 11)
Computer Science Education     Hybrid Journal   (Followers: 12)
Computer Science Journal     Open Access   (Followers: 20)

        1 2 3 4 5 6 | Last

Journal Cover Automation in Construction
  [SJR: 1.571]   [H-I: 65]   [6 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0926-5805
   Published by Elsevier Homepage  [3042 journals]
  • Skeleton estimation of excavator by detecting its parts
    • Authors: Mohammad Mostafa Soltani; Zhenhua Zhu; Amin Hammad
      Pages: 1 - 15
      Abstract: Publication date: October 2017
      Source:Automation in Construction, Volume 82
      Author(s): Mohammad Mostafa Soltani, Zhenhua Zhu, Amin Hammad
      Knowing the near real-time pose of the construction equipment is an important necessity for improving safety and productivity of construction processes. A safer construction site can be achieved by accurately capturing the movements of the equipment and their parts using motion tracking techniques. Recently, the application of Computer Vision (CV) techniques is growing, especially considering that other techniques have difficulties with the deployment and high cost. From the productivity point of view, knowing the pose of the equipment helps to estimate the time that the operator spent on each state of his/her operations. For this purpose, each part or joint of the equipment must be recognized and tracked. Extracting this information requires either using depth sensors or stereo vision, which includes the image information of two or more Red Green Blue (RGB) cameras that have overlapping views. Since the reading range of the common and affordable depth sensors are limited to few meters, this research chooses to use RGB cameras. The most challenging step for this purpose is to process the data of each camera individually for extracting the 2D skeleton of the equipment. After having the 2D skeleton of the equipment from each camera, the 3D pose can be further estimated using the relative rotation and translation information between the cameras coordinate systems. This paper mainly focuses on determining the 2D skeleton of excavators based on the videos received from the cameras available on the site. The method takes advantage of synthetic images of each excavator's part to train the parts' detectors. After detecting the parts, the backgrounds of the detected parts are subtracted. The remaining pixels from the previous step are processed to estimate the skeleton of each part. The final skeleton of the excavator is derived by connecting the individual skeletons of each part to their adjacent parts considering the kinematic information of the excavator.
      Graphical abstract image

      PubDate: 2017-07-24T07:22:44Z
      DOI: 10.1016/j.autcon.2017.06.023
      Issue No: Vol. 82 (2017)
       
  • Corrigendum to “Object composite query method using IFC and LandXML
           based on BIM linkage model” [Autom. Constr. (2017) 14–23]
    • Authors: Tae Wook Kang
      First page: 1
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Tae Wook Kang


      PubDate: 2017-04-25T20:05:59Z
      DOI: 10.1016/j.autcon.2017.04.011
      Issue No: Vol. 81 (2017)
       
  • On human-centric and robot-centric perspective of a building model
    • Authors: Wojciech Turek; Krzysztof Cetnarowicz; Adam Borkowski
      Pages: 2 - 16
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Wojciech Turek, Krzysztof Cetnarowicz, Adam Borkowski
      The effectiveness of mobile robots operating in buildings depends strongly on their ability to cooperate with people. The cooperation requires a common language for communication. In this paper, the problem of modelling buildings in the context of communication between humans and robots is considered. Significant differences between the perception of building elements by humans and robots are discussed at the onset. This analysis allows us to propose a human-oriented building model, which represents elements, features and relations used by people in communication. This model warrants the unambiguous identification of building elements, which forms a good basis for the communication between humans and robots. Further, the model is implemented by means of a flexible, document-based database. Finally, a mapping between the proposed model and the existing robot-oriented models of buildings is proposed, followed by case studies that demonstrate the usage of the proposed methodology.

      PubDate: 2017-05-13T08:38:24Z
      DOI: 10.1016/j.autcon.2017.03.018
      Issue No: Vol. 81 (2017)
       
  • Mining implicit 3D modeling patterns from unstructured temporal BIM log
           text data
    • Authors: Saman Yarmohammadi; Reza Pourabolghasem; Daniel Castro-Lacouture
      Pages: 17 - 24
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Saman Yarmohammadi, Reza Pourabolghasem, Daniel Castro-Lacouture
      Building information modeling is instrumental in documenting design, enhancing customer experience, and improving product functionality in capital projects. However, good building models do not happen by accident, but rather as a result of a managed process that involves several participants from different disciplines and backgrounds. Effective management of this process requires an ability to closely monitor the modeling process and correctly measure modelers' performance. Nevertheless, existing methods of performance monitoring in building design practices lack an objective measurement system to quantify modeling progress. The widespread utilization of Building Information Modeling (BIM) tools presents a unique opportunity to retrieve granular design process data and conduct accurate performance measurements. As a building's 3D model is gradually developed, model generation software packages, such as Autodesk Revit, automatically create log files that record design activities. This paper investigates what information these log files contain and how one can extract and further analyze the information to provide insight into the design modeling process. The specific objectives of this study were to: (1) investigate the presence of implicit patterns in 3-D design log files; and (2) to empirically characterize the performance of modelers based on the time it takes them to execute similar modeling tasks. To fulfill these objectives, design log files provided by an international architecture and design firm were analyzed. Using a tailored text file parser, user-model interaction data including modeler characteristics, command type, and command time were extracted from the journal files. To identify implicit command execution patterns, a sequence mining algorithm based on Generalized Suffix Trees (GST) was implemented. It was shown that there is a statistically significant difference between the average time it takes modelers to execute each command sequence. This study extends the existing knowledge by proposing a novel methodology to extract meaningful patterns from time-stamped unstructured design log data. This research contributes to the state of practice by providing a better understanding of information embedded in design log files.

      PubDate: 2017-05-23T04:14:15Z
      DOI: 10.1016/j.autcon.2017.04.012
      Issue No: Vol. 81 (2017)
       
  • Enhanced discrete particle swarm optimization path planning for UAV
           vision-based surface inspection
    • Authors: Manh Duong Phung; Cong Hoang Quach; Tran Hiep Dinh; Quang Ha
      Pages: 25 - 33
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Manh Duong Phung, Cong Hoang Quach, Tran Hiep Dinh, Quang Ha
      In built infrastructure monitoring, an efficient path planning algorithm is essential for robotic inspection of large surfaces using computer vision. In this work, we first formulate the inspection path planning problem as an extended travelling salesman problem (TSP) in which both the coverage and obstacle avoidance were taken into account. An enhanced discrete particle swarm optimization (DPSO) algorithm is then proposed to solve the TSP, with performance improvement by using deterministic initialization, random mutation, and edge exchange. Finally, we take advantage of parallel computing to implement the DPSO in a GPU-based framework so that the computation time can be significantly reduced while keeping the hardware requirement unchanged. To show the effectiveness of the proposed algorithm, experimental results are included for datasets obtained from UAV inspection of an office building and a bridge.

      PubDate: 2017-05-23T04:14:15Z
      DOI: 10.1016/j.autcon.2017.04.013
      Issue No: Vol. 81 (2017)
       
  • Optimal single-machine batch scheduling for the manufacture,
           transportation and JIT assembly of precast construction with changeover
           costs within due dates
    • Authors: Liulin Kong; Hanbin Luo
      Pages: 34 - 43
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Liulin Kong, Hanbin Luo
      The manufacture, transportation and on-site assembly sectors of precast construction projects are often considered separately and managed by rule of thumb, causing an inefficient use of resources and postponed delivery. This study views these sectors as a whole from the perspective of a single machine batch-scheduling problem. A dynamic programming algorithm, which aims to search for solutions that entail maximum production efficiency, was developed accordingly with the constraints of changeover costs and production deadlines. We tested the method’s ability by processing as many products as possible simultaneously using real data collected from a precast factory in a simulation and compared the effect with a previous study. We found that our method possesses great potential to improve the efficiency of precast production.
      Graphical abstract image

      PubDate: 2017-05-23T04:14:15Z
      DOI: 10.1016/j.autcon.2017.03.016
      Issue No: Vol. 81 (2017)
       
  • Formulating project-level building information modeling evaluation
           framework from the perspectives of organizations: A review
    • Authors: Ying Zhou; Lieyun Ding; Yang Rao; Hanbin Luo; Benachir Medjdoub; Hua Zhong
      Pages: 44 - 55
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Ying Zhou, Lieyun Ding, Yang Rao, Hanbin Luo, Benachir Medjdoub, Hua Zhong
      This study identifies Building Information Modeling (BIM) benefits in the presentations of previous project participants and specialties. Based on recent data, a framework for evaluating the project-level BIM benefits from the perspectives of different stakeholders involved in the project is proposed. In order to maximize the benefits for each user or stakeholder, the functions and methods for implementing BIM on construction projects are explained. The results show that the advantages of implementing BIM in construction projects can be effectively evaluated by the proposed framework. Results presented herein provide documentation to improve the understanding of BIM benefits to all construction industry stakeholders.

      PubDate: 2017-05-28T04:31:43Z
      DOI: 10.1016/j.autcon.2017.05.004
      Issue No: Vol. 81 (2017)
       
  • Towards user centered building design: Identifying end-user lighting
           preferences via immersive virtual environments
    • Authors: Arsalan Heydarian; Evangelos Pantazis; Alan Wang; David Gerber; Burcin Becerik-Gerber
      Pages: 56 - 66
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Arsalan Heydarian, Evangelos Pantazis, Alan Wang, David Gerber, Burcin Becerik-Gerber
      In this paper, a systematic approach is presented to (1) collect end-user lighting-related behavior by using immersive virtual environments (IVEs) as an experimental tool, (2) integrate the collected data with building performance simulation (BPS) tools in order to translate behavioral information into quantitative measures (i.e., preferred lux level), and (3) incorporate user preference data for evaluating design alternatives with the objective of meeting end-user lighting preferences while reducing the building lighting-related energy consumption. To evaluate the applicability of this approach, 89 participants' lighting preferences, performance (reading speed and comprehension), personality traits, and environmental views were collected in IVEs. BPS tools were used to translate participants' lighting preferences into quantitative lux distributions, which were then used to evaluate alternative designs and make user-centered design decisions. The results of the experimental study show that participants preferred to have maximum simulated daylighting compared to electric lighting. Additionally, participants with some or maximum levels of simulated daylighting performed significantly better on the assigned reading and comprehension tasks than those that did not have any simulated daylighting available. Lastly, by collecting participant personality traits, it was observed that extroverts are significantly more likely to prefer maximum lighting (maximum electric lighting and simulated daylighting) compared to other people. To demonstrate how the collected data and results could be used during the design phase of buildings, as one example, a design case study is presented, in which the design of the same office space (as the experiment) is improved to meet participants' lighting preferences and increase the available simulated daylighting.

      PubDate: 2017-06-02T07:19:50Z
      DOI: 10.1016/j.autcon.2017.05.003
      Issue No: Vol. 81 (2017)
       
  • An analysis of BIM jobs and competencies based on the use of terms in the
           industry
    • Authors: Miyoung Uhm; Ghang Lee; Boyoung Jeon
      Pages: 67 - 98
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Miyoung Uhm, Ghang Lee, Boyoung Jeon
      The emergence of building information modeling (BIM) has generated several BIM jobs. However, despite opinions by BIM experts, questions regarding BIM jobs and their competencies still have no clear solution. This paper addresses this question by the collection and analysis of 242 online job postings, written in English, from the US, the UK, and China. These 242 job postings comprised a total of 32,495 words, from which 35 types of job titles and 5,998 terms related to job competency were extracted. Sequentially, the 35 job types were classified into eight BIM job types by analyzing the relations between the job titles using the role and position analysis of social network analysis. The eight BIM job types were BIM project manager, director, BIM manager, BIM coordinator, BIM designer, senior architect, BIM mechanical, electrical, and plumbing (MEP) coordinator, and BIM technician. The 5,998 competency-related terms were categorized into 43 competency elements using the O*NET classification as a framework for analysis. The 43 competencies were then subcategorized into essential, common, and job-specific competencies for the eight BIM job types. The findings of this paper could contribute to the research, industry, and academia by a) providing researchers with a scientific foundation for conducting studies related to BIM jobs and competence in the future; b) setting up guidelines for recruiting and training BIM experts in the industry; and c) allowing universities to develop BIM-related courses depending on their educational goals.

      PubDate: 2017-06-16T19:06:21Z
      DOI: 10.1016/j.autcon.2017.06.002
      Issue No: Vol. 81 (2017)
       
  • Remote control of excavator using head tracking and flexible monitoring
           method
    • Authors: Quang Hoan Le; Jae Woo Lee; Soon Yong Yang
      Pages: 99 - 111
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Quang Hoan Le, Jae Woo Lee, Soon Yong Yang
      A contemporary technique used to control tele-operated excavators based on naked-eye feedback exhibited inferior performance compared to those using camera-based visual feedback due to the effect of operator position. To improve the quality of visual feedback, this report presents a novel observation method with regard to the portable control of a tele-operated excavator. First, the former replaced traditional monitors through the implementation of a head mounted display (HMD) to improve user mobility and flexibility. The latter, combined with a head tracking and flexible monitoring method, provided operators with realistic working environment interactions in real-time. The performance of the proposed system was applied to a 1.5-ton excavator for testing based on the experimental approach. The experimental results revealed that operators of the excavator achieved superior performance through usage of the novel observation system.

      PubDate: 2017-06-16T19:06:21Z
      DOI: 10.1016/j.autcon.2017.06.015
      Issue No: Vol. 81 (2017)
       
  • Interlayer adhesion and strength of structures in Contour Crafting -
           Effects of aggregate size, extrusion rate, and layer thickness
    • Authors: Babak Zareiyan; Behrokh Khoshnevis
      Pages: 112 - 121
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Babak Zareiyan, Behrokh Khoshnevis
      Contour Crafting (CC) is a method that builds coherent concrete structures in a layer-by-layer fabrication fashion. During fabrication, layers must be bonded together to make a homogenous structure, as there is no vibration or external force during layer deposition. This research investigates the structural integrity of Contour Crafted structures using experimental approaches to analyze the bond strength between layers. Initially, a concrete mixture which the compressive and tensile strength is significantly improved through modifying the aggregate size and aggregate to cement ratio is developed. The mixture is compatible with an existing extrusion system and it is tested to quantify the strength at interface for different extrusion rate and layer thickness. The results show that an improvement of up to 16% at interface is achievable for different fabrication conditions.

      PubDate: 2017-06-21T18:12:51Z
      DOI: 10.1016/j.autcon.2017.06.013
      Issue No: Vol. 81 (2017)
       
  • Improving construction management of port infrastructures using an
           advanced computer-based system
    • Authors: Gabriel Diaz-Hernandez; Inigo J. Losada; Fernando J. Mendez
      Pages: 122 - 133
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Gabriel Diaz-Hernandez, Inigo J. Losada, Fernando J. Mendez
      This study presents the design, development, scheme and field validation of an early-alert ocean wave system. It is designed to automate, improve, analyse, design and manage the daily construction activities of any harbour at construction stage. The objective is threefold: a) maximise construction safety, with regards to well-known hazards which occur during construction, especially breakwaters that interact with high-energy sea states, b) optimise the transport, by means of specialised vessels, of the refill material, and c) to minimise the construction delay and disruption on a daily basis, thanks to short-term construction forecasting (96h). The system, known as PATO, offers short-term sea states characteristics, at any point near harbour structures, and relevant wave-structure interaction parameters at any harbour construction stage. The system is able to assist harbour project managers by providing accurate ocean wave data through a user-friendly interface.

      PubDate: 2017-06-21T18:12:51Z
      DOI: 10.1016/j.autcon.2017.06.020
      Issue No: Vol. 81 (2017)
       
  • Automatic point cloud coarse registration using geometric keypoint
           descriptors for indoor scenes
    • Authors: M. Bueno; H. González-Jorge; J. Martínez-Sánchez; H. Lorenzo
      Pages: 134 - 148
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): M. Bueno, H. González-Jorge, J. Martínez-Sánchez, H. Lorenzo
      Laser scanner is a powerful tool which helps in the control of as-built construction projects. The automatic registration of the acquired point clouds without the use of artificial targets is a relevant subject in current investigation. This work focuses on extracting descriptive keypoints from geometric point descriptors, in such a way that keypoints are suitable to perform 4 Points Congruent Sets coarse registration without artificial targets. These keypoints are obtained via 3D Difference of Gaussians over geometric scalar values of the points resulting in characteristic salient features. The registration procedure reduced the RMSE around 2cm during coarse registration comparing against state of the art algorithms. These RMSE values allow the subsequence use of fine registration via ICP completing the automation of the registration process. Geometric keypoints are demonstrated to be a suitable way to obtain automatic point cloud registration and open the way to future developments.

      PubDate: 2017-06-21T18:12:51Z
      DOI: 10.1016/j.autcon.2017.06.016
      Issue No: Vol. 81 (2017)
       
  • Machine vision-based model for spalling detection and quantification in
           subway networks
    • Authors: Thikra Dawood; Zhenhua Zhu; Tarek Zayed
      Pages: 149 - 160
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Thikra Dawood, Zhenhua Zhu, Tarek Zayed
      Spalling is a significant surface defect that can compromise the integrity and durability of concrete structures. The detection and evaluation of spalling are predominantly conducted on the basis of visual inspection (VI) techniques. Although these methods can provide substantial inspection data, they are known to be time-consuming, costly, and qualitative in nature. The objective of this paper is to develop an integrated model based on image processing techniques and machine learning to automate consistent spalling detection and numerical representation of distress in subway networks. The integrated model consists of a hybrid algorithm, interactive 3D presentation, and supported by regression analysis to predict spalling depth. First, RGB images are preprocessed by means of a hybrid algorithm to de-noise the image and enhance the crucial clues associated with spalling. Second, a spalling processor is designed to detect distress attributes, thereby providing 3D visualization model of the defect. And third, the depth and severity of spalling distress are measured using a novel regression analysis model in conjunction with image processing techniques in intensity curve projection. The integrated model was validated through 75 images. Regarding the hybrid algorithm, the recall, precision, and accuracy attained, were 91.7%, 94.8%, and 89.3% respectively. The mean, standard deviation of error percentage in spalling region extraction were 11% and 7.1% respectively, while the variance was 25. Also, the regression model was able to satisfactory quantify the spalling depth with an average validity of 93%. The integrated model is a decision support tool, expected to assist infrastructure managers and civil engineers in their future plans and decision making.

      PubDate: 2017-06-21T18:12:51Z
      DOI: 10.1016/j.autcon.2017.06.008
      Issue No: Vol. 81 (2017)
       
  • Integrated detection and tracking of workforce and equipment from
           construction jobsite videos
    • Authors: Zhenhua Zhu; Xiaoning Ren; Zhi Chen
      Pages: 161 - 171
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Zhenhua Zhu, Xiaoning Ren, Zhi Chen
      High definition (HD) video cameras have been used to record daily activities at construction jobsites into videos. These videos contain rich workforce and equipment information for site engineers and project managers to analyze construction productivity, monitor construction progress, inspect jobsite safety, etc. However, it is difficult to automatically retrieve such information from the videos, since existing methods for the detection of construction workforce and equipment could not reach high precision and recall at the same time. This paper presents a novel framework that integrates the visual tracking into the detection of construction workforce and equipment. The integration significantly improves the recall and meanwhile maintains high precision. The proposed framework has been tested in real construction jobsites. Although it does not process the jobsite videos in real time yet, the test results showed that the recall for the detection of construction workforce and equipment was improved by more than 30–50%, while maintain the precision at the same level.

      PubDate: 2017-06-21T18:12:51Z
      DOI: 10.1016/j.autcon.2017.05.005
      Issue No: Vol. 81 (2017)
       
  • A generic method to optimize a redundant serial robotic
           manipulator's structure
    • Authors: Tuomo Kivelä; Jouni Mattila; Jussi Puura
      Pages: 172 - 179
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Tuomo Kivelä, Jouni Mattila, Jussi Puura
      In this paper, an optimization method for a redundant serial robotic manipulator's structure is proposed in order to improve their performance. Optimization was considered in terms of kinematics using the proposed objective function and the non-linear Levenberg-Marquardt algorithm for multi-variate optimization. Range limits of the joints, bounds of the design parameters, and a constrained workspace are enforced in the proposed method. A desired manipulator can be optimized to cover the required task points using dimensional synthesis. This approach effectively optimizes the link lengths of the manipulator and minimizes the position and orientation errors of the tool center point. A commercial heavy-duty hydraulic, underground tunneling manipulator was used to demonstrate the capability of the proposed optimization method. The obtained results encourage the use of the proposed optimization method in automated construction applications, such as underground tunneling, where the confined environment and the required task add challenges in the design of task-based robotic manipulators.

      PubDate: 2017-06-21T18:12:51Z
      DOI: 10.1016/j.autcon.2017.06.006
      Issue No: Vol. 81 (2017)
       
  • Covariance effect analysis of similarity measurement methods for early
           construction cost estimation using case-based reasoning
    • Authors: Joseph Ahn; Moonseo Park; Hyun-Soo Lee; Sung Jin Ahn; Sae-Hyun Ji; Kwonsik Song; Bo-Sik Son
      Pages: 254 - 266
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Joseph Ahn, Moonseo Park, Hyun-Soo Lee, Sung Jin Ahn, Sae-Hyun Ji, Kwonsik Song, Bo-Sik Son
      Quality source data are essential to secure the reliability of early cost estimation, accuracy, and transparency of the estimation process. To improve the reliability of cost estimation results using CBR, a recurring issue in similarity measurement has been to accurately compute the distance among attributes and cases for the retrieval of the most similar singular or plural cases. However, these existing similarity measures have limitations in taking the covariance among attributes into consideration, and reflecting the effects of covariance in the computation of distances among attributes. To deal with this challenging issue, this research examines the weighted Mahalanobis distance based similarity measure applied to CBR cost estimation, and carries out comparative research on the existing distance measurement methods of CBR. To validate the suggested CBR cost model, simulation data test and case studies using 99 multi-family housing complexes are carried out. As a consequence, this research is expected to improve academic value and mathematical and statistical logicality of similarity measurement, especially in application to CBR cost estimation. The results can be further referenced to not only the area of construction cost estimation, but also international market selection, planning and scheduling, noise control and management, and energy management where case-based reasoning can be applied.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.04.009
      Issue No: Vol. 81 (2017)
       
  • Enhancing coordination and safety of earthwork equipment operations using
           Multi-Agent System
    • Authors: Faridaddin Vahdatikhaki; Seied Mohammad Langari; Alhusain Taher; Khaled El Ammari; Amin Hammad
      Pages: 267 - 285
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Faridaddin Vahdatikhaki, Seied Mohammad Langari, Alhusain Taher, Khaled El Ammari, Amin Hammad
      In 2012, according to Bureau of Labor Statistics, the major earthmoving equipment are reported to have accounted primarily or secondarily for nearly 10% of fatalities on construction sites. This alarming statistics, together with the fact that the construction working environment is less structured and predictable than other industries, indicate the need for better coordination and management of equipment on earthwork sites. Location-based Guidance Systems (LGSs) have been introduced and implemented for improving high-precision earthwork operations. However, the state of practice in LGSs is limited to machine-level equipment management. In view of the LGSs ability to control the finest motion of earthwork construction equipment, there is a great potential to boost their applicability at the project level, where decisions about the equipment control are made based on the global consideration of a fleet rather than a local view of one single piece of equipment. Accordingly, the present paper aims to design a Multi-Agent System (MAS) architecture that combines LGS technology with advanced safety management methods to support the equipment operators on the construction site. A two-layer safety mechanism is proposed for the safety management in the MAS that enables proactive and reactive responses for the prevention of equipment-related collisions on the construction site. A case study is developed to validate the proposed method. It is found that the proposed MAS structure is able to effectively address the fleet-level coordination between earthwork equipment and potentially improve the safety of earthwork projects.
      Graphical abstract image

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.04.008
      Issue No: Vol. 81 (2017)
       
  • Computationally efficient change analysis of piece-wise cylindrical
           building elements for proactive project control
    • Authors: Vamsi Sai Kalasapudi; Pingbo Tang; Yelda Turkan
      Pages: 300 - 312
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Vamsi Sai Kalasapudi, Pingbo Tang, Yelda Turkan
      The designs of large-scale building systems, such as Mechanical, Electrical, and Plumbing (MEP) systems, undergo spatial changes during design-construction coordination, and as a result, their as-built conditions deviate, in some cases significantly, from their as-designed conditions. Construction engineers need to detect and analyze the differences between as-designed and as-built conditions of building systems promptly for responsive change management. Existing data-model comparison approaches either cannot correctly detect changed objects packed in small spaces, or cannot handle the computational complexity of comparing detailed as-designed and as-built geometries of MEP systems that contain hundreds or even thousands of elements (e.g., ducts). This paper presents a computationally efficient spatial-change-detection approach that reliably compares as-designed Building Information Models (BIMs) and 3D as-built models derived from laser scan data. It integrates nearest neighbor searching and relational graph based matching approaches to achieve computationally efficient change detection and management. A case study using data collected from a campus building was conducted to compare the new change detection approach proposed in this paper against the state-of-the-art change detection techniques. The results indicate that the proposed approach is capable of making more precise data-model comparisons in a computationally efficient manner compared to existing data-model comparison techniques.
      Graphical abstract image

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.04.001
      Issue No: Vol. 81 (2017)
       
  • Ontology-based semi-supervised conditional random fields for automated
           information extraction from bridge inspection reports
    • Authors: Kaijian Liu; Nora El-Gohary
      Pages: 313 - 327
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Kaijian Liu, Nora El-Gohary
      A large amount of detailed data about bridge conditions and maintenance actions are buried in bridge inspection reports without being used. Information extraction and data analytics open opportunities to leverage this wealth of data for improved bridge deterioration prediction and enhanced maintenance decision making. This paper proposes a novel ontology-based, semi-supervised conditional random fields (CRF)-based information extraction methodology for extracting information entities describing existing deficiencies and performed maintenance actions from bridge inspection reports. The ontology facilitates the analysis of the text based on content and domain-specific meaning. The proposed semi-supervised CRF simultaneously captures the dependency structures as well as the distributions of labeled and unlabeled data in a concave machine-learning function. It learns from a small set of fixed labeled data and, at the same time, dynamically adapts itself to unseen instances by further learning from a large set of unlabeled data for both reduced human effort and high performance. The proposed algorithm achieved an average precision, recall and, F-1 measure of 94.1%, 87.7%, and 90.7%, respectively.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.02.003
      Issue No: Vol. 81 (2017)
       
  • Automated classification of construction site hazard zones by
           crowd-sourced integrated density maps
    • Authors: Heng Li; Xincong Yang; Martin Skitmore; Fenglai Wang; Perry Forsythe
      Pages: 328 - 339
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Heng Li, Xincong Yang, Martin Skitmore, Fenglai Wang, Perry Forsythe
      Current onsite safety management always relies on time-consuming predefinitions of hazardous zones based on the managers' personal capabilities. However, in a typical labor-intensive industry such as construction, the workers themselves can provide a wealth of information for hazard identification. Historical accident-free working locations on site provide a valuable means of recognizing safe workplaces. This paper presents an approach to the automated classification of construction site zones derived from the location tracks of workers collected from a real-time location system (RTLS). Through data mining, filtering and analysis, the location tracks are transformed into grid density maps and continuous density maps. These illustrate the characteristics of spatial-temporal activities onsite as well as providing a visual representation of the distribution of safe and hazardous individual workplaces. A personnel hazard map is generated automatically based on historical accident-free location tracks from a field project using the proposed approach. Compared with the actual workplaces in terms of accuracy, precision, sensitivity and specificity, the evaluation result reveals that the hazardous areas on a construction site can be automatically classified to improve the workplace management of individual workers. The contributions of this research include an automated zone classification algorithm and an evaluation framework consisting of four indicators for hazard awareness onsite.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.04.007
      Issue No: Vol. 81 (2017)
       
  • Concrete bridge deck condition assessment using IR Thermography and Ground
           Penetrating Radar technologies
    • Authors: Saleh Abu Dabous; Salam Yaghi; Sabah Alkass; Osama Moselhi
      Pages: 340 - 354
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Saleh Abu Dabous, Salam Yaghi, Sabah Alkass, Osama Moselhi
      The current practice of bridge inspection relies heavily on visual inspection, which suffers from several limitations, including the safety of the inspection team, the accuracy of subsurface defects detection, and subjectivity. In visual inspection, data collection is time consuming and the collected data is typically documented by completing standard inspection reports. These reports do not provide sufficient visualization of locations and/or the extent of defects. Emerging combinations of non-destructive testing (NDT) technologies and Geographic Information Systems (GIS) have the potential to circumvent some of these limitations. More research is still needed to assess the potential of these technologies to be applied in the field and to address the challenges in deploying them. The challenges include data acquisition and processing, data interpretation to identify the location and extent of defects, and the integration of results obtained from multiple technologies. This research introduces an integrated method utilizing Infrared (IR) Thermography and Ground Penetrating Radar (GPR) technologies to enhance the detection of concrete bridge defects. Integrating results can improve confidence in defect detection and quantification, and as a result can enhance the reliability of the bridge condition rating process. The integrated system is implemented in a case study of a concrete bridge deck in the city of Laval, Quebec, Canada. The obtained results are compared to detailed and visual inspection results conducted on the bridge before its demolition. The study analyzes potential, limitations, and challenges of using the proposed integrated method. In addition, the study demonstrates the feasibility of integrating the collected data in ArcGIS for enhanced visualization of the inspection results.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.04.006
      Issue No: Vol. 81 (2017)
       
  • Automatic key frame extraction in continuous videos from construction
           monitoring by using color, texture, and gradient features
    • Authors: Ling Chen; Yuhong Wang
      Pages: 355 - 368
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Ling Chen, Yuhong Wang
      On-site video recording systems are increasingly used for monitoring construction activities. The recorded videos contain rich and useful jobsite information that can be used for a variety of purposes. The large amount of video data generated by continuous monitoring, however, creates tremendous challenges on data storage and retrieval. Due to the relatively slow pace of construction activities, a significant portion of the recorded data is redundant. Therefore, archiving raw construction videos into a concise and structured set of key frames would facilitate data storage, retrieval and analysis. Three key issues in automatic key frame extraction from construction videos are studied, including the selection of proper video features, scene segmentation, and key frame extraction. New image features and methods are developed to address the three issues. A validation experiment indicates that the developed features and methods can effectively and efficiently extract representative key frames from the complex and dynamic construction videos. The developed techniques can be used to develop a construction video summary system that serves the purpose of effectively archiving construction jobsite videos.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.04.004
      Issue No: Vol. 81 (2017)
       
  • Multiple representation approach to achieve high-performance spatial
           queries of 3D BIM data using a relational database
    • Authors: Wawan Solihin; Charles Eastman; Yong-Cheol Lee
      Pages: 369 - 388
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Wawan Solihin, Charles Eastman, Yong-Cheol Lee
      We propose an approach using multiple representations to achieve high-performance spatial queries on 3D BIM data. The geometry data is first stored as a simple polyhedron representation inside a relational database supporting the storage of 3D geometry polyhedra. Additional representations are derived from the main geometry for ready use in many applications such as rule checking. The additional representations include a shape approximation using bounding boxes as the roughest approximation, octree decomposition using non-uniform octree cell size that also serves as a spatial index for the geometry, and its boundary representations by the topological faces that are indexed. The octree decomposition is used for efficient spatial indexing. The octree cells are decoded into a one-dimensional string so that it can be indexed using the ordinary binary tree index supported in the relational database, allowing for high-performance spatial queries. Commonly used spatial queries such as intersection and spatial relation between many objects can be efficiently performed using ordinary SQL queries. Using the proposed method, high performance integrated queries of the complete BIM data that includes its geometry can be achieved. The performance of this approach is validated by comparing identical queries against the same data using the native database supported R-tree indexing and the octree-based indexing. It shows a significant performance improvement that is 8 to 234 times faster and the performance is noticeably more consistent.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.03.014
      Issue No: Vol. 81 (2017)
       
  • An exploratory model on the usability of a prototyping-process for
           designing of Smart Building Envelopes
    • Authors: Do-Young Kim; Sung-Ah Kim
      Pages: 389 - 400
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Do-Young Kim, Sung-Ah Kim
      The Smart Building Envelope (SBE) is an interactive system which is adaptive to environmental conditions by transforming its shape and functions. The success of the SBE depends on elaborate interactions among the various building components. The acutely challenging issue is to design the SBE not only to satisfy multidisciplinary requirements but also to orchestrate the technical functions of components. The research objective is to propose an exploratory model on the usability of a prototyping process for SBE design. So the research is related to the conceptualization of the prototyping process model based on complementary use of the Virtual Model (VM) and Smart Physical Model (SPM). The conceptual prototyping process model is appropriate for consideration of the characteristics of the architectural design, the resources of the educational environment and the limitations of the novice designer. Furthermore, the prototyping process model in this research will help in the formulation of guidelines for the educational process, which in turn will help not merely to make intricate engineering products but also to introduce observed results into the architectural design process.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.03.012
      Issue No: Vol. 81 (2017)
       
  • Fuzzy duration forecast model for wind turbine construction project
           subject to the impact of wind uncertainty
    • Authors: Sy-Jye Guo; Jung-Hsing Chen; Chia-Hsin Chiu
      Pages: 401 - 410
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Sy-Jye Guo, Jung-Hsing Chen, Chia-Hsin Chiu
      Wind energy is one of the most promising renewable energy and wind farm is globally constructed for sustainable development. However, wind could produce adverse effects on some wind-sensitive tasks of wind turbine construction projects. Due to limited understanding of how wind may influence productivity in wind turbine construction project, this research presents a fuzzy duration forecast model for wind turbine construction project subject to the impact of wind uncertainty. Through the use of Beaufort scale, professional expertise, and fuzzy membership functions, the productivity loss (PL) subject to various Beaufort scale of wind can be analyzed. With historical wind speed data incorporated, the duration can be simulated and forecasted by the model. Besides, the practicality of the model is demonstrated by an actual wind turbine construction project. The findings from this research are very useful in allocating schedule risk for wind turbine construction projects where wind uncertainty arises.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.03.009
      Issue No: Vol. 81 (2017)
       
  • Optimal crew routing for linear repetitive projects using graph theory
    • Authors: Ahmed Gouda; Ossama Hosny; Khaled Nassar
      Pages: 411 - 421
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Ahmed Gouda, Ossama Hosny, Khaled Nassar
      The line-of-balance (LOB) technique is considered as an effective tool for planning and scheduling linear repetitive construction projects. One of the main assumptions of the LOB technique is the uniformity and constancy of production rate for an activity. Moreover, some aspects of the LOB technique can be modified in order to suit the nature of construction projects. This paper proposes a hybrid approach for scheduling linear projects that optimizes resource allocation using the LOB scheduling technique. The paper presents an optimization model for resolving resource constraint dilemmas in linear scheduling projects. The proposed model utilizes a Matrix Laboratory (MATLAB) code using graph theory as a searching algorithm to automate the model formulation. The novelty of the model is that it supports decision makers in formulating the optimal crews routing among various activities and also considering the allocation of multitasking skilled crews. A case study for a repetitive 4-km sewage pipeline installation is used to test the capabilities of the proposed model. Results show that the model can feasibly reduce the number of crews employed in linear repetitive construction projects.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.03.007
      Issue No: Vol. 81 (2017)
       
  • Automated large capacity multi-story garage—Concept and modeling of
           client service processes
    • Authors: Czesław Pypno; Grzegorz Sierpiński
      Pages: 422 - 433
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Czesław Pypno, Grzegorz Sierpiński
      The paper analyzes the service process of proposed multi-automated garage with a capacity of approximately 1000 parking spaces. By using specific construction techniques this solution is competitive to other solutions implemented in many places of the world. The paper also contains a short review of existing solutions and shows the additional value provided from the proposed garage concept. Queuing theory was used to describe the service process (transport of vehicles) from the points of input into to output from the garage. In this case, the automatic garage was treated as a complex system of mass service (queuing system). The general advantage of the proposed solution is the possibility of parallel service of 10 vehicles by using only one lift (resulting in savings of place and time). At the end of the paper, proposals for further work are also described.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.03.006
      Issue No: Vol. 81 (2017)
       
  • Integrating building and urban semantics to empower smart
           water solutions
    • Authors: Shaun Howell; Yacine Rezgui; Thomas Beach
      Pages: 434 - 448
      Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81
      Author(s): Shaun Howell, Yacine Rezgui, Thomas Beach
      Current urban water research involves intelligent sensing, systems integration, proactive users and data-driven management through advanced analytics. The convergence of building information modeling with the smart water field provides an opportunity to transcend existing operational barriers. Such research would pave the way for demand-side management, active consumers, and demand-optimized networks, through interoperability and a system of systems approach. This paper presents a semantic knowledge management service and domain ontology which support a novel cloud-edge solution, by unifying domestic socio-technical water systems with clean and waste networks at an urban scale, to deliver value-added services for consumers and network operators. The web service integrates state of the art sensing, data analytics and middleware components. We propose an ontology for the domain which describes smart homes, smart metering, telemetry, and geographic information systems, alongside social concepts. This integrates previously isolated systems as well as supply and demand-side interventions, to improve system performance. A use case of demand-optimized management is introduced, and smart home application interoperability is demonstrated, before the performance of the semantic web service is presented and compared to alternatives. Our findings suggest that semantic web technologies and IoT can merge to bring together large data models with dynamic data streams, to support powerful applications in the operational phase of built environment systems.

      PubDate: 2017-07-12T02:32:05Z
      DOI: 10.1016/j.autcon.2017.02.004
      Issue No: Vol. 81 (2017)
       
  • A review of developments in energy storage systems for hybrid excavators
    • Authors: Hongmei Wang; Qingfeng Wang; Baozan Hu
      Pages: 1 - 10
      Abstract: Publication date: August 2017
      Source:Automation in Construction, Volume 80
      Author(s): Hongmei Wang, Qingfeng Wang, Baozan Hu
      Hybrid technology applied to vehicles and construction machineries is one of the promising technologies to address environmental challenges. The energy storage system with higher power density, higher energy density, small size, long lifetime and low cost is essential for the hybrid system. This paper firstly analyzes the difference among the energy storing elements especially for battery and super capacitor (SC). Secondly, the advantages and disadvantages of different structures of energy storage systems are analyzed and compared. Thirdly, the energy storage systems and control strategies in hybrid excavators designed by different manufacturers and research institutions are analyzed in detail. Finally, the challenges in the energy storage system of hybrid excavators are discussed.

      PubDate: 2017-04-04T17:31:45Z
      DOI: 10.1016/j.autcon.2017.03.010
      Issue No: Vol. 80 (2017)
       
  • Conceptualising the FinDD API plug-in: A study of BIM-FM integration
    • Authors: E.A. Pärn; D.J. Edwards
      Pages: 11 - 21
      Abstract: Publication date: August 2017
      Source:Automation in Construction, Volume 80
      Author(s): E.A. Pärn, D.J. Edwards
      This research paper reports upon a client driven approach to iteratively develop the FinDD application programming interface (API) plug-in. FinDD integrates building information modelling (BIM) and facilities management (FM) via the novel development and application of totems. Totems visualise rich semantic FM data in a 3D object to extend the use and application of COBie thereby minimising costs incurred by the FM team to update and maintain the as-built BIM. Participatory action research was used to develop the proof of concept and involved a study of two multi-storey, mixed-use educational buildings (with a contract value worth ≥£150 million UK Sterling) located within Birmingham, UK. The lead researcher worked for the client's estates department and was instrumental in liaising with members of the project management team, synthesising their semantic data requirements and developing the FinDD API plug-in for Autodesk Revit. Research findings reveal that whilst FinDD was positively received as a bespoke extension of COBie (that was tailored to specifically meet client needs), further development is required to mitigate software inflexibility and augment automation of semantic data transfer, storage and analysis. Future work will validate the API plug-in via user experience and integrate additional databases such as post occupancy evaluations (POE).
      Graphical abstract image

      PubDate: 2017-04-04T17:31:45Z
      DOI: 10.1016/j.autcon.2017.03.015
      Issue No: Vol. 80 (2017)
       
  • A shared ontology approach to semantic representation of BIM data
    • Authors: Mehrdad Niknam; Saeed Karshenas
      Pages: 22 - 36
      Abstract: Publication date: August 2017
      Source:Automation in Construction, Volume 80
      Author(s): Mehrdad Niknam, Saeed Karshenas
      Architecture, engineering, construction and facility management (AEC-FM) projects involve a large number of participants that must exchange information and combine their knowledge for successful completion of a project. Currently, most of the AEC-FM domains store their information about a project in text documents or use XML, relational, or object-oriented formats that make information integration difficult. The AEC-FM industry is not taking advantage of the full potential of the Semantic Web for streamlining sharing, connecting, and combining information from different domains. The Semantic Web is designed to solve the information integration problem by creating a web of structured and connected data that can be processed by machines. It allows combining information from different sources with different underlying schemas distributed over the Internet. In the Semantic Web, all data instances and data schema are stored in a graph data store, which makes it easy to merge data from different sources. This paper presents a shared ontology approach to semantic representation of building information. The semantic representation of building information facilitates finding and integrating building information distributed in several knowledge bases. A case study demonstrates the development of a semantic based building design knowledge base.

      PubDate: 2017-04-04T17:31:45Z
      DOI: 10.1016/j.autcon.2017.03.013
      Issue No: Vol. 80 (2017)
       
  • Clustering of architectural floor plans: A comparison of
           shape representations
    • Authors: Eugénio Rodrigues; David Sousa-Rodrigues; Mafalda Teixeira de Sampayo; Adélio Rodrigues Gaspar; Álvaro Gomes; Carlos Henggeler Antunes
      Pages: 48 - 65
      Abstract: Publication date: August 2017
      Source:Automation in Construction, Volume 80
      Author(s): Eugénio Rodrigues, David Sousa-Rodrigues, Mafalda Teixeira de Sampayo, Adélio Rodrigues Gaspar, Álvaro Gomes, Carlos Henggeler Antunes
      Generative design methods are able to produce a large number of potential solutions of architectural floor plans, which may be overwhelming for the decision-maker to cope with. Therefore, it is important to develop tools which organise the generated data in a meaningful manner. In this study, a comparative analysis of four architectural shape representations for the task of unsupervised clustering is presented. Three of the four shape representations are the Point Distance, Turning Function, and Grid-Based model approaches, which are based on known descriptors. The fourth proposed representation, Tangent Distance, calculates the distances of the contour's tangents to the shape's geometric centre. A hierarchical agglomerative clustering algorithm is used to cluster a synthetic dataset of 72 floor plans. When compared to a reference clustering, despite good perceptual results with the use of the Point Distance and Turning Function representations, the Tangent Distance descriptor (Rand index of 0.873) provides the best results. The Grid-Based descriptor presents the worst results.
      Graphical abstract image

      PubDate: 2017-04-11T17:47:45Z
      DOI: 10.1016/j.autcon.2017.03.017
      Issue No: Vol. 80 (2017)
       
  • Bibliometric analysis and review of Building Information Modelling
           literature published between 2005 and 2015
    • Authors: Rúben Santos; António A. Costa; António Grilo
      Pages: 118 - 136
      Abstract: Publication date: August 2017
      Source:Automation in Construction, Volume 80
      Author(s): Rúben Santos, António A. Costa, António Grilo
      The use of Building Information Modelling (BIM) has increased in recent years, mostly due to the potential of the methodology for improving construction project performance and efficiency. With a view to achieving a better understanding of the research work on this subject, this paper conducts a bibliometric analysis and a review of existing literature on BIM focusing on the last decade. The authors selected the articles published in journals with an impact factor higher then 1.0, as well as the top 100 most cited articles. The search resulted on 381 articles, which were then categorised in order to systematise the research conducted over the years. The authors have not only analysed the existing literature but also highlighted new emerging fields in BIM research, being possible to identify Collaborative Environments and Interoperability, Sustainable Construction, BIM Adoption & Standardisation, and BIM Programming as the categories with the most significant growth in the last years. It was also observed that the most researched topics were related with the development of BIM tools, the study of BIM adoption worldwide, the energy simulation using BIM-based information and, more recently, with the semantic interoperability and ontology. On the other hand, the study on BIM at the academic level is very small, as well as parametric modelling and quantity take-off.

      PubDate: 2017-04-25T20:05:59Z
      DOI: 10.1016/j.autcon.2017.03.005
      Issue No: Vol. 80 (2017)
       
  • A force transmission assessment method for thrust system in shield
           machines based on the relative coefficient in compound ground
    • Authors: Kongshu Deng; Cong Xiang; Bangliang Meng; Huangong Wang
      Abstract: Publication date: Available online 21 July 2017
      Source:Automation in Construction
      Author(s): Kongshu Deng, Cong Xiang, Bangliang Meng, Huangong Wang
      An evaluation method for force transmission in the thrust system of tunneling machines in compound ground was investigated in this study. First, the mechanical model for a pushing system in heterogeneous ground was constructed. Then, the relative coefficient of eccentricity on a conical surface was determined based on the mechanical model. Subsequently, the uniformity degree of force transmission in the thrust system was measured using the relative thrust coefficients of eccentricity. Eventually, the performance of force transmission under various arrangements with an equal number of jacks was discussed in detail by applying the conical model of eccentricity to the thrust mechanism of a tunneling machine used in engineering projects. The 3D parameter models for the thrust system of an earth pressure balance shield machine (diameter: 6.34m) were established using SolidWorks. In addition, a propelling system with 22 hydraulic cylinders was simulated via the automatic dynamic analysis of mechanical systems (ADAMS). Results of the numerical analysis agree well with those simulated by ADAMS. The results provide a theoretical basis and support for choosing a non-equidistant driving system in a composite stratum.

      PubDate: 2017-07-24T07:22:44Z
      DOI: 10.1016/j.autcon.2017.07.002
       
  • Automatic building accessibility diagnosis from point clouds
    • Authors: Balado Arias
      Abstract: Publication date: Available online 20 July 2017
      Source:Automation in Construction
      Author(s): J. Balado, L. Díaz-Vilariño, P. Arias, M. Soilán
      Building accessibility diagnosis is of high interest especially in case of people with reduced mobility. This paper proposes a methodology for automated detection of inaccessible steps in building façade entrances from MLS (mobile laser scanner) data. Our approach uses the MLS trajectory to automatically subdivide urban point clouds into regular stretches. From each stretch, the lower zone of façade is isolated and selected as region of interest. Points belonging to vertical elements are projected onto a 2D image and steps are detected and classified as inaccessible areas according to the comparison of geometrical features such as height jump, proximity to ground and width, with regulation. The methodology has been tested in four real datasets, which constitute >400m of different urban scenarios. Results exhibit a robust performance under urban scenes with a high variability of façade geometry due to the presence of different entrance types to shops and dwellings. Results have been quantitatively evaluated and they show global F1 value around 93%. Moreover, the methodology is very fast since 100m are processed in <2min.

      PubDate: 2017-07-24T07:22:44Z
       
  • Inside Front Cover: Editorial Board
    • Abstract: Publication date: September 2017
      Source:Automation in Construction, Volume 81


      PubDate: 2017-07-12T02:32:05Z
       
  • Agent-based modeling and simulation of earthmoving operations
    • Authors: Ahmad Jabri; Tarek Zayed
      Abstract: Publication date: Available online 24 June 2017
      Source:Automation in Construction
      Author(s): Ahmad Jabri, Tarek Zayed
      Discrete-Event Simulation (DES) models are constructed from sequential duration-based activities. DES is used in modeling several construction operations including earthmoving. Current earthmoving models cannot accommodate equipment units with different specifications performing the same task. In addition, activity durations are calculated based on primitive methods such as interpolating existing durations of similar activities in previous projects. Finally, model elements behave in a predetermined manner, ignoring special operational real-life scenarios that occur due to resource constraints. These limitations often lead to inaccuracies in calculating productivity and equipment utilization. This paper applies Agent-Based Modeling and Simulation (ABMS) as an effective bottom-up tool to modeling earthmoving operations. An Agent-Based (AB) earthmoving model consisting of smart, adaptive agents is developed. Each agent is assigned a state chart and a set of static and dynamic properties (attributes and variables) to direct its interactions with the environment and with other agents. This framework proves how modeling earthmoving from the agent's prospective and basing agents' interactions on their properties allow for modeling equipment units with different specifications performing the same task (e.g. trucks of different capacities), as well as for an accurate representation of activity durations, resource handling and resource constraint scenarios. A Java-based application named Agent-Based Simulator for Earthmoving Operations (ABSEMO) is developed as an implementation of the proposed model. ABSEMO will be helpful to contractors in planning earthmoving operations according to the AB approach. A real-life case study of a riverbed excavation in a dam construction project is simulated using ABSEMO, and the results are compared with those obtained from existing simulation models to verify ABSEMO's logic. A percentage difference of 0.42% from the existing results is obtained, indicating that the model's flow of resources is indeed accurate.

      PubDate: 2017-07-03T06:48:14Z
      DOI: 10.1016/j.autcon.2017.06.017
       
  • A multi-server information-sharing environment for cross-party
           collaboration on a private cloud
    • Authors: Jianping Zhang; Qiang Liu; Zhenzhong Hu; Jiarui Lin; Fangqiang Yu
      Abstract: Publication date: Available online 23 June 2017
      Source:Automation in Construction
      Author(s): Jianping Zhang, Qiang Liu, Zhenzhong Hu, Jiarui Lin, Fangqiang Yu
      Interoperability remains the key problem in multi-discipline collaboration based on building information modeling (BIM). Although various methods have been proposed to solve the technical issues of interoperability, such as data sharing and data consistency; organizational issues, including data ownership and data privacy, remain unresolved to date. These organizational issues prevent different stakeholders from sharing their data due to concerns regarding losing control of the data. This study proposes a multi-server information-sharing approach on a private cloud after analyzing the requirements for cross-party collaboration to address the aforementioned issues and prepare for massive data handling in the near future. This approach adopts a global controller to track the location, ownership and privacy of the data, which are stored in different servers that are controlled by different parties. Furthermore, data consistency conventions, parallel sub-model extraction, and sub-model integration with model verification are investigated in depth to support information sharing in a distributed environment and to maintain data consistency. Thus, with this approach, the ownership and privacy of the data can be controlled by its owner while still enabling certain required data to be shared with other parties. Application of the multi-server approach for information interoperability and cross-party collaboration is illustrated using a real construction project of an airport terminal. Validation shows that the proposed approach is feasible for maintaining the ownership and privacy of the data while supporting cross-party data sharing and collaboration at the same time, thus avoiding possible legal problems regarding data copyrights or other legal issues.

      PubDate: 2017-07-03T06:48:14Z
      DOI: 10.1016/j.autcon.2017.06.021
       
  • Metaheuristics for multi-mode cash flow balanced project scheduling with
           stochastic duration of activities
    • Authors: Minjing Ning; Zhengwen He; Tao Jia; Nengmin Wang
      Abstract: Publication date: Available online 22 June 2017
      Source:Automation in Construction
      Author(s): Minjing Ning, Zhengwen He, Tao Jia, Nengmin Wang
      This study investigates the multi-mode cash flow balanced project scheduling problem with stochastic duration of activities. The objective is to generate a robust baseline schedule to minimize the contractor's maximal cumulative gap between cash outflows and cash inflows. Owing to the NP-hardness of the problem, we develop two metaheuristics, i.e. simulated annealing (SA) and tabu search (TS), which have different search structures and are equipped with an improvement measure, to solve the problem. An extensive computational experiment is conducted on a data set generated by ProGen to evaluate the performance of the metaheuristics. The results demonstrate the effects of the improvement measure and indicate that the efficiency of TS decreases, whereas that of SA tends to increase with increasing problem scale. The influence of the key parameters on the objective function is analyzed and the following conclusions are drawn: The contractor's maximal gap of cumulative cash flows decreases with an increase in the expected project deadline, times of attenuation coefficient, payment number, compensation proportion, advanced payment proportion, whereas it increases with an increase in the times of marginal cost and the retention proportion.

      PubDate: 2017-07-03T06:48:14Z
      DOI: 10.1016/j.autcon.2017.06.011
       
  • Activity analysis of construction equipment using audio signals and
           support vector machines
    • Authors: Chieh-Feng Cheng; Abbas Rashidi; Mark A. Davenport; David V. Anderson
      Abstract: Publication date: Available online 22 June 2017
      Source:Automation in Construction
      Author(s): Chieh-Feng Cheng, Abbas Rashidi, Mark A. Davenport, David V. Anderson
      In the construction industry, especially for civil infrastructure projects, a large portion of overall project expenses are allocated towards various costs associated with heavy equipment. As a result, continuous tracking and monitoring of tasks performed by construction heavy equipment is vital for project managers and jobsite personnel. The current approaches for automated construction equipment monitoring include both location and action tracking methods. Current construction equipment action recognition and tracking methods can be divided into two major categories: 1) using active sensors such as accelerometers and gyroscopes and 2) implementing computer vision algorithms to extract information by processing images and videos. While both categories have their own advantages, the limitations of each mean that the industry still suffers from the lack of an efficient and automatic solution for the construction equipment activity analysis problem. In this paper we propose an innovative audio-based system for activity analysis (and tracking) of construction heavy equipment. Such equipment usually generates distinct sound patterns while performing certain tasks, and hence audio signal processing could be an alternative solution for solving the activity analysis problem within construction jobsites. The proposed system consists of multiple steps including filtering the audio signals, converting them into time-frequency representations, classifying these representations using machine learning techniques (e.g., a support vector machine), and window filtering the output of the classifier to differentiating between different patterns of activities. The proposed audio-based system has been implemented and evaluated using multiple case studies from several construction jobsites and the results demonstrate the potential capabilities of the system in accurately recognizing various actions of construction heavy equipment.

      PubDate: 2017-07-03T06:48:14Z
      DOI: 10.1016/j.autcon.2017.06.005
       
  • PyroShield - A HVAC fire curtain testing robot
    • Authors: Alice Beckett; Robert Ross
      Abstract: Publication date: Available online 21 June 2017
      Source:Automation in Construction
      Author(s): Alice Beckett, Robert Ross
      Fire curtains (or dampers), as found in HVAC ducts, are drop-down thermally triggered fire-resistant barriers designed to block the spread of fire and smoke. Regulations stipulate regular mechanical drop-down testing as a visual inspection may not identify rust or jamming which may prevent a curtain from falling. Currently it is difficult to test these curtains as many HVAC ducts are small (340mm ×330mm) and access hatches often don’t allow direct external access to the thermal fuse. Hence complete testing may require the temporary (and expensive) removal of plaster walls, floors or ceilings. This paper describes a pair of tele-operated robots which are designed to mechanically test the operation and serviceability of the fire curtain. Significant experimentation has demonstrated that the testing procedure requires a skilled operator and can be performed typically within a 15minute timeframe without the expense of renovation and remediation procedures.

      PubDate: 2017-07-03T06:48:14Z
      DOI: 10.1016/j.autcon.2017.06.009
       
  • Porosity- and reliability-based evaluation of concrete-face rock dam
           compaction quality
    • Authors: Peng Lv; Xiaoling Wang; Zhen Liu; Jia Yu; Minghui Liu
      Abstract: Publication date: Available online 21 June 2017
      Source:Automation in Construction
      Author(s): Peng Lv, Xiaoling Wang, Zhen Liu, Jia Yu, Minghui Liu
      Compaction quality evaluation of concrete-faced rockfill dams (CFRDs) is a complex nonlinear process. Conventional evaluation methods depend on random spot tests, and porosity is considered as the main evaluation index. However, reliability of results is neglected in existing studies. Considering compaction parameters, material properties and their variability characteristics, an evaluation approach of CFRD compaction quality based on porosity and reliability is proposed. Reliability analysis is introduced to measure the variability in highly variable factors and calculate the porosity- and reliability-based index. Porosities of the entire work area are predicted using an elitist genetic algorithm-based artificial neural network, which are consistent with the measured values with an error <5%. Data used in this study are based on the results from the real-time monitoring system for construction quality and spot tests accumulated during construction. The applicability of the proposed approach is demonstrated by an illustrative case study in China.

      PubDate: 2017-07-03T06:48:14Z
      DOI: 10.1016/j.autcon.2017.06.019
       
  • Inside Front Cover: Editorial Board
    • Abstract: Publication date: August 2017
      Source:Automation in Construction, Volume 80


      PubDate: 2017-04-25T20:05:59Z
       
  • Retrieving similar cases for construction project risk management using
           Natural Language Processing techniques
    • Authors: Yang Zou; Arto Kiviniemi; Stephen W. Jones
      Abstract: Publication date: Available online 18 April 2017
      Source:Automation in Construction
      Author(s): Yang Zou, Arto Kiviniemi, Stephen W. Jones
      Case-based reasoning (CBR) is an important approach in construction project risk management. It emphasises that previous knowledge and experience of accidents and risks are highly valuable and could contribute to avoiding similar risks in new situations. In the CBR cycle, retrieving useful information is the first and the most important step. To facilitate the CBR for practical use, some researchers and organisations have established construction accident databases and their size is growing. However, as those documents are written in everyday language using different ways of expression, how information in similar cases is retrieved quickly and accurately from the database is still a huge challenge. In order to improve the efficiency and performance of risk case retrieval, this paper proposes an approach of combining the use of two Natural Language Processing (NLP) techniques, i.e. Vector Space Model (VSM) and semantic query expansion, and outlines a framework for this Risk Case Retrieval System. A prototype system is developed using the Python programming language to support the implementation of the proposed method. Preliminary test results show that the proposed system is capable of retrieving similar cases automatically and returning, for example, the top 10 similar cases.

      PubDate: 2017-04-19T17:56:13Z
      DOI: 10.1016/j.autcon.2017.04.003
       
  • Enhancing the ifcOWL ontology with an alternative representation for
           geometric data
    • Authors: Pieter Pauwels; Thomas Krijnen; Walter Terkaj; Jakob Beetz
      Abstract: Publication date: Available online 4 April 2017
      Source:Automation in Construction
      Author(s): Pieter Pauwels, Thomas Krijnen, Walter Terkaj, Jakob Beetz
      Over the past few years, several suggestions have been made of how to convert an EXPRESS schema into an OWL ontology. The conversion from EXPRESS to OWL is of particular use to the architectural design and construction industry, because one of the key data models in this domain, namely the Industry Foundation Classes (IFC), is represented using the EXPRESS information modelling language. These conversion efforts have by now resulted in a recommended ifcOWL ontology that stays semantically close to the EXPRESS schema. Two major improvements could be made in addition to this ifcOWL basis. First, the ontology could be split into diverse modules, making it easier to use subsets of the entire ontology. Second, geometric aggregated data (e.g. lists of coordinates) could be serialised into alternative, less complex semantic structures. The purpose of both improvements is to make ifcOWL data smaller in size and complexity. In this article, we focus entirely on the second topic, namely the optimization of geometric data in the semantic representation. We outline and discuss the diverse available options in optimizing the data representations used. We quantify the impact of these measures on the ifcOWL ontology and instance model size. We conclude with an explicit recommendation and give an indication of how this recommendation might be implemented in combination with the already available ifcOWL ontology.

      PubDate: 2017-04-04T17:31:45Z
      DOI: 10.1016/j.autcon.2017.03.001
       
  • Corrosiveness mapping of bridge decks using image-based analysis of GPR
           data
    • Authors: Mona Abouhamad; Thikra Dawood; Ahmad Jabri; Mohammed Alsharqawi; Tarek Zayed
      Abstract: Publication date: Available online 31 March 2017
      Source:Automation in Construction
      Author(s): Mona Abouhamad, Thikra Dawood, Ahmad Jabri, Mohammed Alsharqawi, Tarek Zayed
      Ground Penetrating Radar (GPR), a locating instrument by design, has attracted much interest as a non-destructive inspection technique for bridge decks due to its ease of use and ability to detect corrosion. The most commonly used technique to interpret GPR data is numerical analysis. The assessment method relies on the fact that corroded reinforcing bars, which cause signal attenuation, can be easily identified using GPR scans. However, several other unrelated factors can attenuate GPR signals such as reinforcing bar depth, surface anomalies and reinforcing bar spacing. These anomalies can be falsely interpreted as deterioration using numerical analysis. Image-based analysis overcomes these drawbacks through analyzing the entire GPR profile while considering prior knowledge of the structure characteristics, thus determining the state of bridge deck. The main objective of this research is to develop a systematic framework of the image-based analysis. The framework is supported by various GPR profiles depicting several causes of signal attenuation and their analysis with respect to deterioration or rebar corrosion status. Two case studies are presented and analyzed using numerical analysis, image-based analysis, and other Non-Destructive Evaluation (NDE) techniques. The results are compared to confirm the validity of the proposed methodology. Further validation is done using concrete cores. The developed approach is believed to assist transportation agencies in a more informed decision making process through highlighting areas of actual deterioration.

      PubDate: 2017-04-04T17:31:45Z
      DOI: 10.1016/j.autcon.2017.03.004
       
  • Investigation of the causality patterns of non-helmet use behavior of
           construction workers
    • Authors: Heng Li; Xiaoying Li; Xiaochun Luo; Joanna Siebert
      Abstract: Publication date: Available online 22 March 2017
      Source:Automation in Construction
      Author(s): Heng Li, Xiaoying Li, Xiaochun Luo, Joanna Siebert
      Not wearing a safety helmet can result in serious injuries on construction sites, but the cause of such unsafe behavior is not yet well understood. This paper describes a practical field study to find the factors that influence non-helmet use on construction sites using a real-time tracking system (the Eye on Project or EOP), which is developed by our research team to provide an objective record of helmet use; and which overcomes the deficiencies of traditional recording methods (i.e. self-reporting). The application of association rules then combines designated risk factors and finds the causality patterns of non-helmet use. Based on the analyses, this paper develops a method of evaluating workers' risk level involving the intensity of multiple risk factors.

      PubDate: 2017-03-27T18:31:57Z
      DOI: 10.1016/j.autcon.2017.02.006
       
 
 
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