for Journals by Title or ISSN
for Articles by Keywords
  Subjects -> ENGINEERING (Total: 2336 journals)
    - CHEMICAL ENGINEERING (200 journals)
    - CIVIL ENGINEERING (192 journals)
    - ELECTRICAL ENGINEERING (105 journals)
    - ENGINEERING (1225 journals)
    - HYDRAULIC ENGINEERING (56 journals)
    - INDUSTRIAL ENGINEERING (70 journals)
    - MECHANICAL ENGINEERING (94 journals)

CIVIL ENGINEERING (192 journals)                     

Showing 1 - 192 of 192 Journals sorted alphabetically
ACI Structural Journal     Full-text available via subscription   (Followers: 19)
Acta Polytechnica : Journal of Advanced Engineering     Open Access   (Followers: 2)
Acta Structilia : Journal for the Physical and Development Sciences     Open Access   (Followers: 2)
Advances in Civil Engineering     Open Access   (Followers: 39)
Advances in Structural Engineering     Full-text available via subscription   (Followers: 31)
Agregat     Open Access   (Followers: 1)
Ambiente Construído     Open Access   (Followers: 1)
American Journal of Civil Engineering and Architecture     Open Access   (Followers: 33)
Architectural Engineering     Open Access   (Followers: 4)
Archives of Civil and Mechanical Engineering     Full-text available via subscription   (Followers: 2)
Archives of Civil Engineering     Open Access   (Followers: 13)
Archives of Hydro-Engineering and Environmental Mechanics     Open Access   (Followers: 2)
ATBU Journal of Environmental Technology     Open Access   (Followers: 4)
Australian Journal of Structural Engineering     Full-text available via subscription   (Followers: 6)
Baltic Journal of Road and Bridge Engineering     Full-text available via subscription   (Followers: 1)
BER : Building and Construction : Full Survey     Full-text available via subscription   (Followers: 11)
BER : Building Contractors' Survey     Full-text available via subscription   (Followers: 4)
BER : Building Sub-Contractors' Survey     Full-text available via subscription   (Followers: 3)
BER : Survey of Business Conditions in Building and Construction : An Executive Summary     Full-text available via subscription   (Followers: 4)
Bioinspired Materials     Open Access   (Followers: 5)
Bridge Structures : Assessment, Design and Construction     Hybrid Journal   (Followers: 16)
Building & Management     Open Access   (Followers: 1)
Building and Environment     Hybrid Journal   (Followers: 15)
Building Women     Full-text available via subscription  
Built Environment Project and Asset Management     Hybrid Journal   (Followers: 15)
Bulletin of Pridniprovsk State Academy of Civil Engineering and Architecture     Open Access   (Followers: 6)
Canadian Journal of Civil Engineering     Hybrid Journal   (Followers: 13)
Case Studies in Engineering Failure Analysis     Open Access   (Followers: 7)
Case Studies in Nondestructive Testing and Evaluation     Open Access   (Followers: 12)
Case Studies in Structural Engineering     Open Access   (Followers: 9)
Cement and Concrete Composites     Hybrid Journal   (Followers: 17)
Challenge Journal of Concrete Research Letters     Open Access   (Followers: 2)
Challenge Journal of Structural Mechanics     Open Access   (Followers: 6)
Change Over Time     Full-text available via subscription   (Followers: 2)
Civil and Environmental Engineering     Open Access   (Followers: 8)
Civil And Environmental Engineering Reports     Open Access   (Followers: 7)
Civil and Environmental Research     Open Access   (Followers: 20)
Civil Engineering = Siviele Ingenieurswese     Full-text available via subscription   (Followers: 4)
Civil Engineering and Architecture     Open Access   (Followers: 21)
Civil Engineering and Environmental Systems     Hybrid Journal   (Followers: 3)
Civil Engineering and Technology     Open Access   (Followers: 11)
Civil Engineering Dimension     Open Access   (Followers: 10)
Civil Engineering Infrastructures Journal     Open Access   (Followers: 1)
Cohesion and Structure     Full-text available via subscription   (Followers: 2)
Composite Structures     Hybrid Journal   (Followers: 279)
Computer-aided Civil and Infrastructure Engineering     Hybrid Journal   (Followers: 11)
Computers & Structures     Hybrid Journal   (Followers: 37)
Concrete Research Letters     Open Access   (Followers: 6)
Construction Economics and Building     Open Access   (Followers: 4)
Construction Engineering     Open Access   (Followers: 11)
Construction Management and Economics     Hybrid Journal   (Followers: 23)
Construction Science     Open Access   (Followers: 5)
Constructive Approximation     Hybrid Journal  
Curved and Layered Structures     Open Access   (Followers: 3)
DFI Journal : The Journal of the Deep Foundations Institute     Hybrid Journal   (Followers: 1)
Earthquake Engineering and Structural Dynamics     Hybrid Journal   (Followers: 17)
Enfoque UTE     Open Access   (Followers: 4)
Engineering Project Organization Journal     Hybrid Journal   (Followers: 7)
Engineering Structures     Hybrid Journal   (Followers: 13)
Engineering Structures and Technologies     Hybrid Journal   (Followers: 2)
Engineering, Construction and Architectural Management     Hybrid Journal   (Followers: 14)
Environmental Geotechnics     Hybrid Journal   (Followers: 5)
European Journal of Environmental and Civil Engineering     Hybrid Journal   (Followers: 9)
Fatigue & Fracture of Engineering Materials and Structures     Hybrid Journal   (Followers: 17)
Frattura ed Integrità Strutturale : Fracture and Structural Integrity     Open Access  
Frontiers in Built Environment     Open Access  
Frontiers of Structural and Civil Engineering     Hybrid Journal   (Followers: 6)
Geomaterials     Open Access   (Followers: 4)
Geosystem Engineering     Hybrid Journal   (Followers: 1)
Geotechnik     Hybrid Journal   (Followers: 3)
Géotechnique Letters     Hybrid Journal   (Followers: 7)
GISAP : Technical Sciences, Construction and Architecture     Open Access  
HBRC Journal     Open Access   (Followers: 2)
Hormigón y Acero     Full-text available via subscription  
HVAC&R Research     Hybrid Journal  
Indonesian Journal of Urban and Environmental Technology     Open Access  
Indoor and Built Environment     Hybrid Journal   (Followers: 2)
Infrastructure Asset Management     Hybrid Journal   (Followers: 2)
Infrastructures     Open Access  
Ingenio Magno     Open Access   (Followers: 1)
Insight - Non-Destructive Testing and Condition Monitoring     Full-text available via subscription   (Followers: 29)
International Journal for Service Learning in Engineering     Open Access  
International Journal of 3-D Information Modeling     Full-text available via subscription   (Followers: 3)
International Journal of Advanced Structural Engineering     Open Access   (Followers: 18)
International Journal of Civil, Mechanical and Energy Science     Open Access   (Followers: 1)
International Journal of Concrete Structures and Materials     Open Access   (Followers: 14)
International Journal of Condition Monitoring     Full-text available via subscription   (Followers: 2)
International Journal of Construction Engineering and Management     Open Access   (Followers: 10)
International Journal of Geo-Engineering     Open Access   (Followers: 3)
International Journal of Geosynthetics and Ground Engineering     Full-text available via subscription   (Followers: 4)
International Journal of Masonry Research and Innovation     Hybrid Journal   (Followers: 1)
International Journal of Pavement Research and Technology     Open Access   (Followers: 6)
International Journal of Protective Structures     Hybrid Journal   (Followers: 6)
International Journal of Steel Structures     Hybrid Journal   (Followers: 2)
International Journal of Structural Engineering     Hybrid Journal   (Followers: 10)
International Journal of Structural Integrity     Hybrid Journal   (Followers: 2)
International Journal of Structural Stability and Dynamics     Hybrid Journal   (Followers: 7)
International Journal of Sustainable Built Environment     Open Access   (Followers: 4)
International Journal of Sustainable Construction Engineering and Technology     Open Access   (Followers: 9)
International Journal on Pavement Engineering & Asphalt Technology     Open Access   (Followers: 7)
International Journal Sustainable Construction & Design     Open Access  
Journal of Bridge Engineering     Full-text available via subscription   (Followers: 15)
Journal of Building Engineering     Hybrid Journal   (Followers: 1)
Journal of Building Materials and Structures     Open Access   (Followers: 2)
Journal of Building Performance Simulation     Hybrid Journal   (Followers: 6)
Journal of Civil Engineering and Construction Technology     Open Access   (Followers: 14)
Journal of Civil Engineering and Management     Hybrid Journal   (Followers: 7)
Journal of Civil Engineering and Science     Open Access   (Followers: 9)
Journal of Civil Engineering Research     Open Access   (Followers: 7)
Journal of Civil Engineering, Science and Technology     Open Access   (Followers: 1)
Journal of Civil Society     Hybrid Journal   (Followers: 4)
Journal of Civil Structural Health Monitoring     Hybrid Journal   (Followers: 4)
Journal of Composites for Construction     Full-text available via subscription   (Followers: 13)
Journal of Computing in Civil Engineering     Full-text available via subscription   (Followers: 25)
Journal of Construction Engineering     Open Access   (Followers: 8)
Journal of Construction Engineering and Management     Full-text available via subscription   (Followers: 19)
Journal of Constructional Steel Research     Hybrid Journal   (Followers: 8)
Journal of Earth Sciences and Geotechnical Engineering     Open Access   (Followers: 4)
Journal of Fluids and Structures     Hybrid Journal   (Followers: 6)
Journal of Frontiers in Construction Engineering     Open Access   (Followers: 2)
Journal of Green Building     Full-text available via subscription   (Followers: 11)
Journal of Highway and Transportation Research and Development (English Edition)     Full-text available via subscription   (Followers: 14)
Journal of Infrastructure Systems     Full-text available via subscription   (Followers: 21)
Journal of Legal Affairs and Dispute Resolution in Engineering and Construction     Full-text available via subscription   (Followers: 5)
Journal of Marine Science and Engineering     Open Access   (Followers: 1)
Journal of Materials and Engineering Structures     Open Access   (Followers: 5)
Journal of Materials in Civil Engineering     Full-text available via subscription   (Followers: 10)
Journal of Nondestructive Evaluation     Hybrid Journal   (Followers: 11)
Journal of Performance of Constructed Facilities     Full-text available via subscription   (Followers: 4)
Journal of Pipeline Systems Engineering and Practice     Full-text available via subscription   (Followers: 7)
Journal of Rehabilitation in Civil Engineering     Open Access   (Followers: 3)
Journal of Solid Waste Technology and Management     Full-text available via subscription   (Followers: 1)
Journal of Structural Engineering     Full-text available via subscription   (Followers: 40)
Journal of Structural Fire Engineering     Full-text available via subscription   (Followers: 6)
Journal of Sustainable Architecture and Civil Engineering     Open Access   (Followers: 3)
Journal of Sustainable Design and Applied Research in Innovative Engineering of the Built Environment     Open Access   (Followers: 1)
Journal of the Civil Engineering Forum     Open Access  
Journal of the South African Institution of Civil Engineering     Open Access   (Followers: 4)
Journal of Water and Environmental Nanotechnology     Open Access  
Jurnal Spektran     Open Access   (Followers: 1)
Jurnal Teknik Sipil dan Perencanaan     Open Access   (Followers: 1)
Konstruksia     Open Access  
KSCE Journal of Civil Engineering     Hybrid Journal   (Followers: 2)
Latin American Journal of Solids and Structures     Open Access   (Followers: 4)
Materiales de Construcción     Open Access   (Followers: 1)
Mathematical Modelling in Civil Engineering     Open Access   (Followers: 4)
Nondestructive Testing And Evaluation     Hybrid Journal   (Followers: 17)
npj Materials Degradation     Open Access  
Obras y Proyectos     Open Access   (Followers: 1)
Open Journal of Civil Engineering     Open Access   (Followers: 9)
Photonics and Nanostructures - Fundamentals and Applications     Hybrid Journal   (Followers: 3)
Practice Periodical on Structural Design and Construction     Full-text available via subscription   (Followers: 4)
Proceedings of the Institution of Civil Engineers - Bridge Engineering     Hybrid Journal   (Followers: 8)
Proceedings of the Institution of Civil Engineers - Civil Engineering     Hybrid Journal   (Followers: 13)
Proceedings of the Institution of Civil Engineers - Management, Procurement and Law     Hybrid Journal   (Followers: 9)
Proceedings of the Institution of Civil Engineers - Municipal Engineer     Hybrid Journal   (Followers: 3)
Proceedings of the Institution of Civil Engineers - Structures and Buildings     Hybrid Journal   (Followers: 4)
Random Structures and Algorithms     Hybrid Journal   (Followers: 5)
Research in Nondestructive Evaluation     Hybrid Journal   (Followers: 7)
Revista IBRACON de Estruturas e Materiais     Open Access   (Followers: 1)
Road Materials and Pavement Design     Hybrid Journal   (Followers: 11)
Russian Journal of Nondestructive Testing     Hybrid Journal   (Followers: 6)
Science and Engineering of Composite Materials     Hybrid Journal   (Followers: 61)
Selected Scientific Papers - Journal of Civil Engineering     Open Access   (Followers: 3)
Slovak Journal of Civil Engineering     Open Access   (Followers: 2)
Soils and foundations     Full-text available via subscription   (Followers: 5)
Steel Construction - Design and Research     Hybrid Journal   (Followers: 3)
Structural and Multidisciplinary Optimization     Hybrid Journal   (Followers: 10)
Structural Concrete     Hybrid Journal   (Followers: 11)
Structural Control and Health Monitoring     Hybrid Journal   (Followers: 9)
Structural Engineering International     Full-text available via subscription   (Followers: 12)
Structural Mechanics of Engineering Constructions and Buildings     Open Access   (Followers: 1)
Structural Safety     Hybrid Journal   (Followers: 7)
Structural Survey     Hybrid Journal  
Structure     Full-text available via subscription   (Followers: 24)
Structure and Infrastructure Engineering: Maintenance, Management, Life-Cycle Design and Performance     Hybrid Journal   (Followers: 14)
Structures     Hybrid Journal   (Followers: 1)
Study of Civil Engineering and Architecture     Open Access   (Followers: 10)
Superlattices and Microstructures     Hybrid Journal   (Followers: 2)
Surface Innovations     Hybrid Journal  
Technical Report Civil and Architectural Engineering     Open Access   (Followers: 1)
Teknik     Open Access  
The IES Journal Part A: Civil & Structural Engineering     Hybrid Journal   (Followers: 6)
The Structural Design of Tall and Special Buildings     Hybrid Journal   (Followers: 6)
Thin Films and Nanostructures     Full-text available via subscription   (Followers: 2)
Thin-Walled Structures     Hybrid Journal   (Followers: 4)
Transactions of the VŠB - Technical University of Ostrava. Construction Series     Open Access   (Followers: 1)
Transportation Geotechnics     Full-text available via subscription   (Followers: 1)
Transportation Infrastructure Geotechnology     Hybrid Journal   (Followers: 8)
Underground Space     Open Access  
Water Science & Technology     Partially Free   (Followers: 25)
Water Science and Technology : Water Supply     Partially Free   (Followers: 22)


Journal Cover Structural and Multidisciplinary Optimization
  [SJR: 1.603]   [H-I: 77]   [10 followers]  Follow
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1615-1488 - ISSN (Online) 1615-147X
   Published by Springer-Verlag Homepage  [2351 journals]
  • Special issue: a comprehensive study on enhanced optimization-based model
           calibration using gradient information
    • Authors: Guesuk Lee; Guilian Yi; Byeng D. Youn
      Abstract: Model calibration is the process of estimating unknown inputs in a model to improve the agreement between model predictions and experimental observations. Optimization-based model calibration is a probabilistic approach for estimating unknown inputs by using optimization techniques. Gradient-based optimization algorithms are popular for optimization-based model calibration because of their computational efficiency. Gradient-based algorithms, however, also have drawbacks that include the local optimum issue, the numerical noise issue, lack of gradient information, and related concerns. In optimization-based model calibration, a calibration metric that quantifies the similarity or difference between two probability distributions (the predicted and the observed system responses) is defined as an objective function. Current methods of optimization-based model calibration use existing calibration metrics, such as the likelihood function and the probability residual. Occasionally, these methods show inaccurate calibrated results. Therefore, first, this comprehensive study investigates the root causes of the inaccurate calibrated results that arise from using existing calibration metrics. Second, an enhanced method is proposed to achieve robust optimization-based model calibration by providing analytical gradient information. This study provides a general guideline for improved optimization-based model calibration.
      PubDate: 2018-02-27
      DOI: 10.1007/s00158-018-1920-8
  • Reliability-based design optimization under sampling uncertainty: shifting
           design versus shaping uncertainty
    • Authors: Sangjune Bae; Nam H. Kim; Seung-gyo Jang
      Abstract: The objective of this paper is a tradeoff between changing design and controlling sampling uncertainty in reliability-based design optimization (RBDO). The former is referred to as ‘living with uncertainty’, while the latter is called ‘shaping uncertainty’. In RBDO, a conservative estimate of the failure probability is defined using the mean and the upper confidence limit, which are obtained from samples and from the normality assumption. Then, the sensitivity of the conservative probability of failure is derived with respect to design variables as well as the number of samples. It is shown that the proposed sensitivity is much more accurate than that of the finite difference method and close to the analytical sensitivity. A simple RBDO example showed that once the design variables reach near the optimum point, the number of samples is adjusted to satisfy the conservative reliability constraints. This example showed that not only shifting design but also shaping uncertainty plays a critical role in the optimization process.
      PubDate: 2018-02-24
      DOI: 10.1007/s00158-018-1936-0
  • Modeling of piezoelectric sensors adhesively bonded on trusses using a
           mathematical programming approach
    • Authors: Hector A. Tinoco
      Abstract: In this study, piezoelectric sensors design adhesively bonded on truss elements is treated in the framework of mathematical programming. A numerical formulation based on the strength capacity of set structure, adhesive and piezoelectric sensor is proposed. Inside the formulations maximum strength capacity of the adhesive is considered as a limit value in the design. Two formulations are established to obtain the maximum strength of the set; the first one is built on the basis of finite differences and the other one on a formulation of finite elements both based on an admissible static field. The lower bound method applied to limit analysis is extended in this research to analyze trusses with sensors including the adhesive interface. Four examples are designed to assess the numerical methodologies in which the results are compared with other known data. The main contribution of this work is focused on finding the maximum coupling load that a piezoelectric sensor can read before being debonded based on the minimum size constraint of the sensor.
      PubDate: 2018-02-21
      DOI: 10.1007/s00158-018-1933-3
  • Multi-objective optimization of a composite stiffened panel for hybrid
           design of stiffener layout and laminate stacking sequence
    • Authors: Haichao An; Shenyan Chen; Hai Huang
      Abstract: This paper presents a two-level approximation method for multi-objective optimization of a composite stiffened panel. The purpose is to seek the minimum structural mass and maximum fundamental frequency subject to given displacement constraints and manufacturing limitations. The design variables are the stiffener layout, and laminate stacking sequences for stiffeners and the panel skin. By introducing the concept of ground structure in both stiffener layout and laminate stacking sequence, the design problem is formulated with mixed discrete and continuous variables. Two types of discrete variables represent the existence of each stiffener and the existence of each ply in the laminate, respectively, with continuous ones for ply thicknesses. Considering the objectives are of different dimensions, a weighted min-max objective function is defined and minimized. The problem is firstly made explicit with branched multipoint approximate functions. Genetic algorithm (GA) is then adopted to optimize two types of discrete variables, determining which stiffeners/layers are deleted or retained. For fitness calculation in GA, a second-level approximation is built to optimize continuous ply thicknesses of the necessary layers that are retained. By giving different initial designs of stiffener layout and laminate stacking sequences, reasonable optimization results, which are tradeoffs between the considered two objectives, are obtained as design options. From the number of required structural analysis, it shows that the proposed method has a good efficiency in seeking rational solutions, which are tradeoffs between conflicting objectives and also feasible designs satisfying all considered constraints.
      PubDate: 2018-02-21
      DOI: 10.1007/s00158-018-1918-2
  • Automatic selection for general surrogate models
    • Authors: Malek Ben Salem; Lionel Tomaso
      Abstract: In design engineering problems, the use of surrogate models (also called metamodels) instead of expensive simulations have become very popular. Surrogate models include individual models (regression, kriging, neural network...) or a combination of individual models often called aggregation or ensemble. Since different surrogate types with various tunings are available, users often struggle to choose the most suitable one for a given problem. Thus, there is a great interest in automatic selection algorithms. In this paper, we introduce a universal criterion that can be applied to any type of surrogate models. It is composed of three complementary components measuring the quality of general surrogate models: internal accuracy (on design points), predictive performance (cross-validation) and a roughness penalty. Based on this criterion, we propose two automatic selection algorithms. The first selection scheme finds the optimal ensemble of a set of given surrogate models. The second selection scheme further explores the space of surrogate models by using an evolutionary algorithm where each individual is a surrogate model. Finally, the performances of the algorithms are illustrated on 15 classical test functions and compared to different individual surrogate models. The results show the efficiency of our approach. In particular, we observe that the three components of the proposed criterion act all together to improve accuracy and limit over-fitting.
      PubDate: 2018-02-20
      DOI: 10.1007/s00158-018-1925-3
  • Surrogate-based global optimization using an adaptive switching infill
           sampling criterion for expensive black-box functions
    • Authors: In-Bum Chung; Dohyun Park; Dong-Hoon Choi
      Abstract: Surrogate-based global optimization algorithms use a surrogate model along with a sampling criterion. The AMP-SBGO algorithm sequentially samples points to gradually find the global optimum. The sampling criterion used to decide where to sample in each iteration dominates the algorithm and directly impacts its efficiency and robustness. This paper presents a method that uses multiple criteria for each phase of sampling, with conditions for switching from one criterion to another. Such behavior can improve the performance of the algorithm by allowing the optimization process to be less influenced by the initial sample points. Each phase, referred to as the global search phase and local search phase, utilizes different techniques. For the global search, a weighted maximin distance metric is proposed that is more efficient than ordinary maximin distance searches, and for the local search, the surrogate is optimized using a multi-start gradient-based optimizer. The algorithm was tested on 9 unconstrained mathematical test functions and 4 classes of GKLS functions along with 5 constrained test problems, which included 4 engineering design problems, and showed significant improvements compared to existing surrogate-based global optimization algorithms. The algorithm was then implemented to optimize the shape of a flange shaft in a washing machine.
      PubDate: 2018-02-20
      DOI: 10.1007/s00158-018-1942-2
  • Pareto front generation with knee-point based pruning for mixed discrete
           multi-objective optimization
    • Authors: Juseong Lee; Sang-Il Lee; Jaemyung Ahn; Han-Lim Choi
      Abstract: This note proposes an algorithm to generate the Pareto front of a mixed discrete multi-objective optimization problem based on the pruning of irrelevant subproblems. The knee point is introduced as a new reference point for pruning decision. The point can overcome the drawback of the existing reference point – over-pruning, and be naturally defined and used in the context of multi-objective optimization. The validity of the proposed procedure is demonstrated through case studies.
      PubDate: 2018-02-19
      DOI: 10.1007/s00158-018-1926-2
  • A sequential element rejection and admission (SERA) topology optimization
           code written in Matlab
    • Authors: Rubén Ansola Loyola; Osvaldo M. Querin; Alain Garaigordobil Jiménez; Cristina Alonso Gordoa
      Abstract: This paper presents the Matlab implementation of the Sequential Element Rejection and Admission (SERA) method for topology optimization of structures and compliant mechanisms. The lines comprising this code include definition of design domain, finite element analysis, sensitivity analysis, mesh-independency filter, optimization algorithm and display of results. Extensions and changes in the algorithm are also included in order to solve multiple load cases, active and passive elements and compliant mechanisms design. The code is intended for educational purposes and introduces an alternative approach to traditional structural topology optimization algorithms. The complete code is provided in the Appendix.
      PubDate: 2018-02-19
      DOI: 10.1007/s00158-018-1939-x
  • Multidisciplinary shape optimization of ductile iron castings by
           considering local microstructure and material behaviour
    • Authors: Jakob Olofsson; Riccardo Cenni; Matteo Cova; Giacomo Bertuzzi; Kent Salomonsson; Joel Johansson
      Abstract: During the casting process and solidification of ductile iron castings, a heterogeneous microstructure is formed throughout the casting. This distribution is strongly influenced by the item geometry and the process related factors, as chemical composition and local solidification conditions. Geometrical changes to the geometry of the casting thus alters the local mechanical behavior and properties, as well as the distribution of stresses and strains when the casting is subjected to load. In order to find an optimal geometry, e.g. with reduced weight and increased load-bearing capacity, this interdependency between geometry and local material behavior needs to be considered and integrated into the optimization method. In this contribution, recent developments in the multidisciplinary integration of casting process simulation, solidification and microstructure modelling, microstructure-based material characterization, finite element structural analyses with local material behavior and structural optimization techniques are presented and discussed. The effect and relevance of considering the local material behavior in shape optimization of ductile iron castings is discussed and evidenced by an industrial application. It is shown that by adopting a multidisciplinary optimization approach by integration of casting simulation and local material behavior into shape optimization, the potential of the casting process to obtain components with high performance and reliability can be enabled and utilized.
      PubDate: 2018-02-17
      DOI: 10.1007/s00158-018-1929-z
  • Topology optimization of pressure structures based on regional contour
           tracking technology
    • Authors: Zhen-mian Li; Jianxing Yu; Yang Yu; LiXin Xu
      Abstract: This article presents a new computational approach to solve the design-dependent loading problem in topology optimization of pressure structures. A simple algorithm based on digital image processing and regional contour tracking technology is proposed that generates the appropriate loading surface during the topology evolution. First, the topological layout produced during the optimization process is transformed into a compact image. Then, the regional contour tracking technology is used to represent the boundary of objects and extract pressure loading elements. At last, the pressures are transferred directly to corresponding element nodes. Due to the semi-automatically determined endpoints of the loading boundaries, the current scheme can deal with structures loaded by pressure from outside the domain, as well as pressure completely contained within the domain. Also, the calculation of the load sensitivities can be avoided in the current scheme. As a simple alternative computational strategy for compliance topology optimization of pressure structures, the current scheme is stable, flexible and efficient. Representative numerical examples are presented to show the validity and advantages of the proposed scheme. Especially, the design of closed containers and storage tanks indicates that it works well for the topology optimization of pressure structures.
      PubDate: 2018-02-17
      DOI: 10.1007/s00158-018-1923-5
  • Modified augmented Lagrangian coordination and alternating direction
           method of multipliers with parallelization in non-hierarchical analytical
           target cascading
    • Authors: Yongsu Jung; Namwoo Kang; Ikjin Lee
      Abstract: Analytical Target Cascading (ATC) is a decomposition-based optimization methodology that partitions a system into subsystems and then coordinates targets and responses among subsystems. Augmented Lagrangian with Alternating Direction method of multipliers (AL-AD), one of efficient ATC coordination methods, has been widely used in both hierarchical and non-hierarchical ATC and theoretically guarantees convergence under the assumption that all subsystem problems are convex and continuous. One of the main advantages of distributed coordination which consists of several non-hierarchical subproblems is that it can solve subsystem problems in parallel and thus reduce computational time. Therefore, previous studies have proposed an augmented Lagrangian coordination strategy for parallelization by eliminating interactions among subproblems. The parallelization is achieved by introducing a master problem and support variables or by approximating a quadratic penalty function to make subproblems separable. However, conventional AL-AD does not guarantee convergence in the case of parallel solving. Our study shows that, in parallel solving using targets and responses of the current iteration, conventional AL-AD causes mismatch of information in updating the Lagrange multiplier. Therefore, the Lagrange multiplier may not reach the optimal point, and as a result, increasing penalty weight causes numerical difficulty in the augmented Lagrangian coordination approach. To solve this problem, we propose a modified AL-AD with parallelization in non-hierarchical ATC. The proposed algorithm uses the subgradient method with adaptive step size in updating the Lagrange multiplier and also maintains penalty weight at an appropriate level not to cause oscillation. Without approximation or introduction of an artificial master problem, the modified AL-AD with parallelization can achieve similar accuracy and convergence with much less computational cost compared with conventional AL-AD with sequential solving.
      PubDate: 2018-02-17
      DOI: 10.1007/s00158-018-1907-5
  • The stepwise accuracy-improvement strategy based on the Kriging model for
           structural reliability analysis
    • Authors: Jian Wang; Zhili Sun
      Abstract: For structural reliability analysis with time-consuming performance functions, an innovative design of experiment (DoE) strategy of the Kriging model is proposed, which is named as the stepwise accuracy-improvement strategy. The epistemic randomness of the performance value at any point provided by the Kriging model is used to derive an accuracy measure of the Kriging model. The basic idea of the proposed strategy is to enhance the accuracy of the Kriging model with the best next point that has the largest improvement with regard to the accuracy measure. An optimization problem is developed to define the best next point. The objective function is the expectation that quantifies how much an untried point could enhance the accuracy of the Kriging model. Markov chain Monte Carlo sampling and Gauss–Hermite quadrature are employed to make several approximations to solve the optimization problem and get the best next point. A structural reliability analysis method is also constructed based on the proposed strategy and the accuracy measure employed. Several examples are studied. The results validate the advantages of the proposed DoE strategy.
      PubDate: 2018-02-14
      DOI: 10.1007/s00158-018-1911-9
  • An advanced method for the sensitivity analysis of safety system
    • Authors: Lijuan Kan; Jihui Xu
      Abstract: Safety system always involves variation on account of the epistemic uncertainty of the inputs. Therefore, it is significant to identify the uncertainty source of the output for the safety system. Sensitivity analysis (SA) which measures the effect of variance variation of inputs on the absolute change in the variance of system unsafety is a useful tool for identifying the importance of inputs. A finite difference method has been proposed to estimate the effect in the existing work. This method may be numerical unstable or inaccuracy and is computational heavy. In order to overcome these issues, an advanced method which combing the simulation method and the analytical deduction of the partial derivative is established in this paper to estimate the SA indices. Discussion and several examples are introduced to illustrate the efficiency and accuracy of the proposed method when comparing with the finite difference method.
      PubDate: 2018-02-13
      DOI: 10.1007/s00158-018-1928-0
  • An 88-line MATLAB code for the parameterized level set method based
           topology optimization using radial basis functions
    • Authors: Peng Wei; Zuyu Li; Xueping Li; Michael Yu Wang
      Abstract: This paper presents a compact and efficient 88-line MATLAB code for the parameterized level set method based topology optimization using radial basis functions (RBFs), which is applied to minimize the compliance of a two-dimensional linear elastic structure. This parameterized level set method using radial basis functions can maintain a relatively smooth level set function with an approximate re-initialization scheme during the optimization process. It also has less dependency on initial designs due to its capability in nucleation of new holes inside the material domain. The MATLAB code and simple modifications are explained in detail with numerical examples. The 88-line code included in the appendix is intended for educational purposes.
      PubDate: 2018-02-13
      DOI: 10.1007/s00158-018-1904-8
  • A ground-structure-based representation with an element-removal algorithm
           for truss topology optimization
    • Authors: Alin Shakya; Pruettha Nanakorn; Wasuwat Petprakob
      Abstract: In this study, a new ground-structure-based representation for truss topology optimization is proposed. The proposed representation employs an algorithm that removes unwanted elements from trusses to obtain the final trusses. These unwanted elements include kinematically unstable elements and useless zero-force elements. Since the element-removal algorithm is used in the translation of representation codes into corresponding trusses, this results in more representation codes in the search space that are mapped into kinematically stable and efficient trusses. Since more representation codes in the search space represent stable and efficient trusses, the strategy increases meaningful competition among representation codes. This remapping strategy alleviates the problem of having large search spaces using ground structures, and encourages faster convergences. To test the effectiveness of the proposed representation, it is used with a simple multi-population particle swarm optimization algorithm to solve several truss topology optimization problems. It is found that the proposed representation can significantly improve the performance of the optimization process.
      PubDate: 2018-02-12
      DOI: 10.1007/s00158-018-1917-3
  • Simultaneous estimation of boundary conditions and material model
    • Authors: Gerhardus J. Jansen van Rensburg; Schalk Kok; Daniel N. Wilke
      Abstract: Room temperature experimental compression test data is available for different hardmetals. This data indicates the presence of some spatial inhomogeneity due to a compression instability, eccentric loading or time varying equivalent bending moment. To account for this, an inverse analysis is employed that determines not only the constitutive material model parameter values but also the displacement boundary conditions that best replicate the experimental data. The unknown boundary displacement history is approached using a systematically refined piecewise linear approximation, determined alongside material parameter values. The systematic simultaneous estimation of material parameter values and boundary approximations is also investigated using a virtual problem for which the exact solution is known. This investigation confirms that known material parameter values and boundary conditions can be recovered without using any prior knowledge of the exact displacement boundary conditions.
      PubDate: 2018-02-12
      DOI: 10.1007/s00158-018-1924-4
  • Optimization via multimodel simulation
    • Authors: Thomas Bartz-Beielstein; Martin Zaefferer; Quoc Cuong Pham
      Abstract: Increasing computational power and the availability of 3D printers provide new tools for the combination of modeling and experimentation. Several simulation tools can be run independently and in parallel, e.g., long running computational fluid dynamics simulations can be accompanied by experiments with 3D printers. Furthermore, results from analytical and data-driven models can be incorporated. However, there are fundamental differences between these modeling approaches: some models, e.g., analytical models, use domain knowledge, whereas data-driven models do not require any information about the underlying processes. At the same time, data-driven models require input and output data, but analytical models do not. The optimization via multimodel simulation (OMMS) approach, which is able to combine results from these different models, is introduced in this paper. We believe that OMMS improves the robustness of the optimization, accelerates the optimization-via-simulation process, and provides a unified approach. Using cyclonic dust separators as a real-world simulation problem, the feasibility of this approach is demonstrated and a proof-of-concept is presented. Cyclones are popular devices used to filter dust from the emitted flue gasses. They are applied as pre-filters in many industrial processes including energy production and grain processing facilities. Pros and cons of this multimodel optimization approach are discussed and experiences from experiments are presented.
      PubDate: 2018-02-12
      DOI: 10.1007/s00158-018-1934-2
  • A density-based topology optimization methodology for thermoelectric
           energy conversion problems
    • Authors: Christian Lundgaard; Ole Sigmund
      Abstract: A density-based topology optimization approach for thermoelectric (TE) energy conversion problems is proposed. The approach concerns the optimization of thermoelectric generators (TEGs) and thermoelectric coolers (TECs). The framework supports convective heat transfer boundary conditions, temperature dependent material parameters and relevant objective functions. Comprehensive implementation details of the methodology are provided, and seven different design problems are solved and discussed to demonstrate that the approach is well-suited for optimizing TEGs and TECs. The study reveals new insight in TE energy conversion, and the study provides guidance for future research, which pursuits the development of high performing and industrially profitable TEGs and TECs.
      PubDate: 2018-02-12
      DOI: 10.1007/s00158-018-1919-1
  • Open-source coupled aerostructural optimization using Python
    • Authors: John P. Jasa; John T. Hwang; Joaquim R. R. A. Martins
      Abstract: To teach multidisciplinary design optimization (MDO) to students effectively, it is useful to have accessible software that runs quickly, allowing hands-on exploration of coupled systems and optimization methods. Open-source software exists for low-fidelity aerodynamic or structural analysis, but there is no existing software for fast tightly coupled aerostructural analysis and design optimization. To address this need, we present OpenAeroStruct, an open-source low-fidelity aerostructural analysis and optimization tool developed in NASA’s OpenMDAO framework. It uses the coupled adjoint method to compute the derivatives required for efficient gradient-based optimization. OpenAeroStruct combines a vortex lattice method and 1-D finite-element analysis to model lifting surfaces, such as aircraft wings and tails, and uses the coupled-adjoint method to compute the aerostructural derivatives. We use the Breguet range equation to compute the fuel burn as a function of structural weight and aerodynamic performance. OpenAeroStruct has proved effective both as an educational tool and as a benchmark for researching new MDO methods. There is much more potential to be exploited as the research community continues to develop and use this tool.
      PubDate: 2018-02-07
      DOI: 10.1007/s00158-018-1912-8
  • An optimality criteria-based algorithm for efficient design optimization
           of laminated composites using concurrent resizing and scaling
    • Authors: Ralph Kussmaul; Markus Zogg; Paolo Ermanni
      Abstract: Numerical optimization is an indispensable part of the design process of laminated composite structures. Several optimality criteria-based algorithms exist which rely on a sequential resizing and scaling approach. This paper presents a novel design algorithm applicable for stiffness and eigenfrequency optimization of composite structures with concurrent consideration of resizing and scaling operations. A method is introduced that allows for an efficient consideration of nonlinear constraints. This is done by determining stable concurrent scaling parameters from first-order constraint change ratio estimations. Optimization is carried out using optimality criteria in three independent steps, namely with respect to fiber angles, ply thickness ratios, and total laminate thickness. Sensitivity analyses are performed analytically at low computational costs. Numerical examples demonstrate the efficiency and fast convergence of the method. Compared to established algorithms, the number of required function evaluations is reduced significantly.
      PubDate: 2018-02-07
      DOI: 10.1007/s00158-018-1927-1
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-