Authors:V. V. Rao; Zulfan Adi Putra, M. R. Bilad, M. D. H. Wirzal, N. A. H. M. Nordin, S. Mahadzir Abstract: Natural gas is conventionally transported in its liquid form or Liquid Natural Gas (LNG). It is then transported using cryogenic insulated LNG tankers. At receiving terminals, LNG is regasified prior to distributing it through gas distribution system. Seawater has been used as the heat source, which leads to vast amount of cold energy discarded into the water. This work presents the use of LNG cold energy around Melaka Refining Company (MRC). The cold energy is utilized in power generation, propylene refrigeration cycle, and air separation plants. These systems are designed and simulated using a commercial process simulation software. Capital cost (CAPEX) function and revenues of each system are further developed as a function of LNG flowrates. These developed correlations are then used in an optimization problem to seek for the most profitable scenario. The results show that utilizing LNG for air separation unit yields the highest profit compared to power generation and refrigeration plants. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:M. Khairudin; R. Refalda, S. Yatmono, H. S. Pramono, A. K. Triatmaja, A Shah Abstract: A very challenging problem in mobile robot systems is mostly in obstacle avoidance strategies. This study aims to describe how the obstacle avoidance system on mobile robots works. This system is designed automatically using fuzzy logic control (FLC) developed using Matlab to help the mobile robots to avoid a head-on collision. The FLC designs were simulated on the mobile robot system. The simulation was conducted by comparing FLC performance to the proportional integral derivative (PID) controller. The simulation results indicate that FLC works better with lower settling time performance. To validate the results, FLC was used in a mobile robot system. It shows that FLC can control the velocity by braking or accelerating according to the sensor input installed in front of the mobile robot. The FLC control system functions as ultrasonic sensor input or a distance sensor. The input voltage was simulated with the potentiometer, whereas the output was shown by the velocity of DC motor. This study employed the simulation work in Simulink and Matlab, while the experimental work used laboratory scale of mobile robots. The results show that the velocity control of DC motors with FLC produces accurate data, so the robot could avoid the existing obstacles. The findings indicate that the simulation and the experimental work of FLC for mobile robot in obstacle avoidance are very close. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:Eman Al Abbad; Fadi Alakhras Abstract: Sorption of Acid Red 1 (AR1) from aqueous solutions utilizing low-cost sorbent material; (chitosan-iso-vanillin) is studied under batch conditions. The remaining concentrations of the azo dye are measured at λmax = 546 nm by UV spectrophotometric method. Langmuir data reveal that the maximum removal capacity was 555.556 mg/g at pH 3. Freundlich isotherm represents the best fitting model on the removal of AR1 using chemically modified chitosan verifying the sorption takes place on heterogeneous surfaces with multilayer adsorption. Kinetic studies of the sorption process revealed that intraparticle diffusion is not only the rate-determining step but also a chemical reaction takes place as well. The results indicate that high sorption rapidness with almost 90% achieved within 90 min. Thermodynamic investigations suggest that the process favours an exothermic nature. The polymer utilized in the present study is being considered as a feasible sorbent material for the removal of AR1 from waste effluent. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:Bentang Arief Budiman; Poetro Lebdo Sambegoro, Samuel Rahardian, Rizky Ilhamsyah, Ridha Firmansyah, Firman Bagja Juangsa, Muhammad Aziz Abstract: This paper exhibits a method to predict the remaining service lifetime of inflatable rubber dam by considering the appearance of deep hole damage. The material used for the rubber dam is a composite comprising three layers of woven fabric as fiber and EPDM/SBR 64 474 rubber as a matrix. The service lifetime is predicted by calculating the degradation of rubber dam’s material properties. Simple Rate Law model and Time-Temperature Superposition model are employed to calculate the rubber properties degradation. A finite element analysis is then conducted to investigate stress and strain distributions which occur in the rubber dam membrane during operational loading. Furthermore, the effect of deep hole damage in the rubber dam, which is caused by improper maintenance, is modeled as well. The results show that a 7 mm depth of the hole can accelerate rubber degradation, which causes catastrophic failure. This can happen because two layers of the woven fabric in the rubber dam have been broken. Suggestion to hold up the degradation is also discussed. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:Suprapto Suprapto; Edy Riyanto Abstract: This paper proposed a grape drying machine using computer vision and Multi-layer Perceptron (MLP) method. Computer vision is for taking grapes’ image on conveyor, whereas MLP is for controlling grape drying machine and classifying its output. To evaluate the proposed, a kind of grapes are put on conveyor of the machine and their images are taken every two min. Some parameters of MLP to control the drying machine includes dried grape, temperature, grape area, motor position, and motion speed. Those parameters are to adjust an appropriate MLP’s output, including motion control and heater control. Two different temperatures are employed on the machine, including 60 and 75°C. The results showed that the grape could be dried with similar area 3800 pixel at the 770th min using temperature 60°C and at the 410th min using temperature 75°C. Comparing between them, the similar ratio could also be achieved at 0.64 with different time 360 min. Indeed, the temperature setting at 75°C resulted faster drying performance. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:Md. Humayun Kabir; Md. Sirajul Islam, Tanmoy Roy Tusher, Md. Enamul Hoq, Shamim Al Mamun Abstract: Heavy metal concentrations in water and fish of the Shitalakhya river was measured to find out the suitability of its water for drinking and irrigation purposes. The concentrations of Pb, Cu, Cr, Zn, Cd and Hg in water were 0.0065; 0.0240; 0.0069; 0.8170; 0.0044; and 0.0057 mg/L, respectively in pre-monsoon, 0.0029; 0.0151; 0.0019; 0.4270; 0.0015; and 0.0020 mg/L, respectively in monsoon, and 0.0040; 0.0212; 0.0039; 0.6520; 0.0029; and 0.0031 mg/L, respectively in post-monsoon season. The heavy metal concentrations were found higher in pre-monsoon followed by post-monsoon and monsoon. The results also depicted that over the three seasons heavy metal pollution index and heavy metal evaluation index for all metals were lower than the critical pollution index value and low heavy metal contamination, respectively, and the degree of contamination in pre-monsoon season stated medium level pollution, followed by post-monsoon and monsoon season. The concentrations of Pb, Cu, and Cr in fish were found less than the lower detection limit, while the Zn were found 25.42; 18.30; and 29.34 mg/kg during the pre-monsoon, monsoon and post-monsoon, respectively. The study concluded that the Shitalakhya river water was not safe for the aquatic environment, especially for aquatic biota. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:Lisna Efiyanti; Dian Anggraini Indrawan, Zulhan Arif, Devandri Hutapea, Ane Dwi Septina Abstract: Biomass, such as wood waste, is one of the resources that can be potentially converted into a carbon product for catalyst applications. In this study, the sulfonated carbon was obtained through the pyrolysis method for wood waste at the temperature of 350°C, which was later sulfonated through the use of H2SO4 (8N) on the reflux for 4 h. The sulfonated carbon was then analyzed and characterized including its water content, ash content, volatile matter, fixed carbon, iodine adsorption as well as the H+ (acidity) capacity using ammonia adsorptions and functional groups and the Fourier Transform Infra-Red (FTIR) instrument. The catalyst application was carried out during the kempili pulp hydrolysis process using a microwave with the ratio of catalyst to a pulp of 1:1 (5g:5g), with the power conditions of 300, 400, and 600 watt for 3, 5, and 7 min. The results showed that the sulfonated carbon catalyst had water content, volatile matter, ash content, fixed carbon, iodine adsorption as well as the catalyst acidity as much as 3.48%; 11.70%; 4.21%; 84.62%; 690.88 mg/g; and 6.45 mmol/g, respectively with the highest glucose content of 160.83 ppm. The carbon-based catalyst is expected as an alternative catalyst, can be further developed for hydrolysis reactions, and can serve as a green technology product in the future. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:Betta Kurniawan; Laila Puspita, Yogi Kurnia, Ismalia Husna, Ali Rahmat, Rofiqul Umam, Bibin B. Andriana, Kittisak Jermsittiparsert Abstract: The purpose of this study was to demonstrate an alternative solution as an insecticide from Indonesian natural ingredients. We investigated the potential use of Artocarpus altilis park (known as kluwih plants in Indonesia) for an anti-mosquito repellent because it contains flavonoids and saponins. The use of this type of insecticide is harmless, inexpensive, and largely available in Indonesia. In the experiment, we extracted bark and leaves of kluwih to obtain insecticidal material to repel Anopheles sp. To ensure the precise extraction and insecticidial effect, the experiments were conducted four times with three repetitions. For each experiment, we used 8.4 mL with the concentrations of 20, 30, and 40% of flavonoid. The results showed that the higher the concentrations of bark and leaf extracts of Artocarpus altilis park the higher the mortality rate of Anopheles sp is. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:Ahmed Ibrahim; A.Al-Awamry Al-Awamry, Ashraf Shawky Mohra Abstract: Long Term Evolution has developed a new radio technology called femtocell or Femto Base station, which is well-suited to improve cellular network capacity and mobile coverage to indoor user's areas. Providing additional capacity and coverage expansion through FBSs could lead to large interference in a cellular radio communication network. In this paper, we proposed an efficient resource allocation scheme based on Fraction Frequency Reuse (FFR) for interference mitigation, where the entire spectrum is shared among network entities. FFR mechanism aims to reduce co-tier and cross-tier downlink interferences by allocating non-overlapping sets of bands to the user equipment at different geographic locations. The main purpose of this work is to compare two main types of FFR schemes, respectively, Strict FFR and Soft Frequency Reuse with the proposed scheme. The three types of FFR schemes were explained and evaluated with Monte-Carlo simulation based on some performance metrics, namely, sum-rate, spectral efficiency, and outage probability. Simulation results showed that the impacts of the proposed scheme are significantly high in comparison with two other methods. The proposed scheme proved to enhance spectral efficiency, reduced the outage probability, and increased the sum rate for all the users. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:Illyass Bazzi; Khadija El Mouaden, Aicha Chaouay, Abdelaziz Ait Addi, Mohamed Hamdani, Souad El Issami, Mustapha Hilali, Belkheir Hammouti, Khalid Abbiche, Rachid Salghi Abstract: The objective of this study was to monitor the bacteriological contamination of the seawater of the marine fisheries of the coastal Agadir, Morocco. The study was focused on the diagnosis on the pollution in heavy metals, such as cadmium, lead, and mercury in five zones: the port of Imi Ouaddar fish boarding (zone Z1), the old port of Agadir (zones Z2 and Z3), the port of Agadir Marina (zone Z4), and the estuary of Oued Souss (zone Z5). The analyses were done by testing physicochemical parameters (such as pH, temperature, dissolved oxygen, salinity and conductivity) as well as microbiological and atomic adsorption analyses. The experimental results showed that the values of the physicochemical parameters were almost the same in all zones, while the microbial conditions were different, in which this is due to the existence of heavy metals. The more heavy metal concentrations affected the condition of microbes in the sea water, confirmed by the number of Escherichia coli. This study demonstrated the importance of controlling concentration of heavy metals for better sustainability of environment. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:Abhijit Kulshreshtha; Abdulkareem Sh. Mahdi Al-Obaidi Abstract: In today’s era of advanced weapons and technology development, many remarkable inventions have shifted the balance of war towards the strategically enhanced military equipped with tactical weapons and armaments. One of these strategic advancements is stealth technology due to which stealth aircraft are high in demand for the military. The question that rises is How to detect a stealth object' This paper proposes a novel anti-stealth technique using void detection, high frequency wave interference and neutrino beam propagation. Void detection method uses a modified satellite-based radar that searches for areas in the aerospace from which the transmitted signals sent to the ground receiving station are blocked or deflected. High frequency wave interference method is used to generate a stellar trajectory of the stealth aircraft at the detected void. Neutrino beam comprises of energy quanta mainly neutrinos, which are able to surpass the absorption or deflection systems in the stealth body of aircraft. This unique phenomenon produces a moving image, which is the precise location of the aircraft in the space. Using these methods, the trajectory of the aircraft is detected which ultimately leads to the detection of the stealth aircraft itself. The newly proposed methods which are theoretically more reliable than the existing methods may not have been tested but the method planning make them practically feasible considering that the technology used is a part of advanced engineering today. PubDate: Tue, 01 Dec 2020 00:00:00 +070
Authors:Nuria Haristiani; Mumu Muhamad Rifa’i Abstract: Transformation of the global learning landscape in twenty-first century is shaped by the uptake of digital technology and social network applications, along with students’ alteration of characteristics, needs, and demands. As an attempt to integrate digital technology and social network application, this study aimed to develop a chatbot-based application integrated with social media LINE to enhance language learning, specifically for learning Japanese grammar. The application, namely Gengobot, is a chatbot-based grammar application, consisting of Japanese Language Proficiency Test Level 5 and Level 4 (N5 and N4) grammar materials in three language: Indonesian, English, and Japanese. This study applied design-based research method with Waterfall application development procedure, and a questionnaire to gather feedbacks from fifty-three students regarding Gengobot features and contents. Gengobot application was successfully developed using code igniter framework, MySQL database, and webhook to integrate Gengobot application with LINE messaging API. Application testing confirmed that Gengobot is successfully developed and operated properly. The students agreed that Gengobot materials and features considered to be adequate, useful, user friendly, and suitable to support language learning. Gengobot is also highly accessible since it is integrated to social media LINE, allowing students to adjust its use to their own learning preference and needs, which is suitable to enhance students’ personal learning environment. PubDate: Sat, 03 Oct 2020 00:00:00 +070
Authors:Faihatuz Zuhairoh; Dedi Rosadi Abstract: This paper discussed Real-time Forecasting of the COVID-19 Epidemic using daily cumulative cases of COVID-19 in South Sulawesi. Our aim is to make model for the growth of COVID-19 cases in South Sulawesi in the top 5 provinces with the largest COVID-19 cases in Indonesia and predict when this pandemic reaches the peak of spread and when it ends. This paper used the Richards model, which is an extension of a simple logistic growth model with additional scaling parameters. Data used in the paper as of June 24, 2020 were taken from the official website of the Indonesian government. Our results are that the maximum cumulative number of COVID-19 cases has reached 10,000 to 12,000 cases. The peak of the pandemic is estimated to occur from June to July 2020 while continuing to impose social restrictions. The condition in South Sulawesi shows a sloping curve around October 2020, which means that there are still additional cases but not significant. When entering November, the curve starts to flat which indicates the addition of very small cases until the pandemic ends. The results of the pandemic peak prediction are the same as the Indonesian data; what is different is the prediction of when the pandemic will end. In the best-case scenario, the current data will tend to slow down, with the COVID-19 pandemic in South Sulawesi expected to end in November 2020. Our modeling procedure can provide information about the ongoing COVID-19 pandemic in South Sulawesi that may facilitate real-time public health responses about future disease outbreaks. PubDate: Thu, 02 Jul 2020 00:00:00 +070
Authors:Saripudin Saripudin; As'Ari Djohar, Dedi Rohendi, Ade Gafar Abdullah Abstract: This paper aims to summarize and analyze the Developing Information Technology in Open CourseWare (OCW) movements and new opportunities in Asia in the context of supporting the education process in higher education that is in accordance with the recent demands for graduate competency supported by IT innovation. The review method is carried out in 3 stages: searching and downloading articles, filtering and sorting, and final screening. The results of this review show that the OCW movement in Asia is growing rapidly, among others, due to IT innovation, stakeholder commitment, public awareness, and the need for quality teaching materials. In the era of web 5.0 technology, lecturers must have the competencies to develop electronic activities through the Web that make students truly active so that online learning actually takes place rather than the electronic reading process. The impact of IT innovation has brought drastic changes in the field of education in the learning process has become an effective driving tool for improving learning outcomes and achieving educational goals, one of the most recent innovations is OCW. OCW movement in Asia has progressed rapidly and significantly, although they experience transformations in accordance with technological developments and needs in the field. PubDate: Tue, 26 May 2020 09:05:04 +070
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