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Techno-economic resilient planning strategy in microgrid islanded system with multiple renewable energy and energy storage system in Malaysia
Get PDFThe purpose of this study is to enhance the conventional power distribution system’s resiliency via critical loads survival metric. A two-stage framework is proposed for this project, where each stage uses a different tool. In stage 1, the viability of using Hybrid Optimization of Multiple Energy Resources (HOMER) Grid software is explored to model a resilience and economic hybrid microgrid (MG) in Malaysia environment and subsequently the optimal distributed generation (DG) sizing is determined. The modeled MG that consists of Renewable Energy System (RES) and Energy Storage System (ESS) contributes to lowering the total net preset cost (NPC), levelized cost of energy (COE), as well as the carbon emissions. In stage 2, power flow study is performed by using Power World software. Optimal DG placement and switching strategy are applied together with the optimal DG size, to see the effectiveness compared to a benchmark system. IEEE 33-bus test system model is used to validate the proposed strategy. The resilience improvement of the proposed strategies was assessed under five worst-case scenarios and validated through nine case study. Finally, the resiliency of the power network is quantified by using a proposed resilient index (RI) formula. Numerical simulations and technical data demonstrate the effectiveness of the proposed resiliency planning strategies in a radial distribution system
Fuzzy PID based navigation of autonomous mobile robot
Get PDFOne of the key aspects of smart manufacturing is the adoption of autonomous intelligent robots that are capable of self-navigating throughout the vicinity of factory without constant specific command by the operators and which can make discission making with regards to navigation. For such purpose many AI- based control systems have been developed however the simplicity and less computational requirement of PID systems are still more preferable to industry. So, there is rise in integrating and using AI based method like PSO, GA, ANN etc. to optimize the gains of PID system. However, adoption of fuzzy based system with PID for the given application is still not very much explored. Therefore, Fuzzy based PID system has to be investigated and developed. As part of the process, this study developed a robotic model from the robot pioneer 3dx and designed a simple PID controller with software tunning to be used as baseline comparison model for fuzzy PID controller
Status of sustainable construction practice in Malaysia: A review paper
No full textImplementing sustainable construction is very important in all developing countries. Malaysia suffers from many serious environmental issues due to irresponsible actions, which include the involvement of construction activities. All parties in the construction industry need to take responsive actions to implement sustainable construction. Previous research has revealed that the implementation of sustainable construction still needs all parties in the construction industry to make improvements. The aim of this paper is to attempt to report on the current status of sustainable construction practice in Malaysia. This paper contains two (2) objectives which are to explore current developments in Malaysia and to determine the status of sustainable construction practice in Malaysia which covers government support, regulation enforcement, a rating system and the consciousness of both developer and consultant in terms of implementation. This article employs a theoretical review of the literature on the status of sustainable construction practice in Malaysia. From the review, it can be concluded that Malaysia is still progressing towards sustainable construction but needs further improvement
High-level design and synthesis of VLSI cell placement algorithm
Get PDFNowadays, chip manufacturers are concerned with the fast time-to-market of the integrated circuit (IC), therefore fast time cycle from design to manufacturing is essential to achieve this goal. The physical design of Very Large-Scale Integration (VLSI) placement is the process of determining the position of each cell on a die surface such that there are no cell overlaps with each other. Moreover, this process is also identifying which affects the timing, routability, power consumption, and performance of a chip. In VLSI cell placement, the most time-consuming task is the IC physical design flow as it involves finding the optimum placement of millions of standard cells and macros in a chip floorplan. The purpose of this study is to improve modern VLSI placement algorithms by using Hardware (HW)/ Software (SW) codesign and High-Level Synthesis (HLS) methodology. The methods in chip floorplan placements can be generally divided into three categories: partition-based placement methods, simulated annealing based methods, and analytical approaches. In this research, the placement algorithm is based on the simulated annealing, and C/C++ programming is developed and validated using standard academic benchmarks from the International Symposium on Physical Design (ISPD) design competition. Some of the critical functions such as the wirelength calculation are synthesized from C to Register-Transfer Level (RTL) using Vivado HLS software for a custom HW implementation and the rest of the algorithm such as data parsing and memory accesses will remain in C, and co-simulated with the custom hardware block. Therefore, this project offers the possibility of using HLS design for VLSI cell placement process where it is proven that using RTL design has improved the execution time in certain functions such as wirelength calculation. Moreover, HLS offers more options in terms of design space exploration as compared to traditional RTL methodology
Mask detection using deep learning method
Get PDFWearing face masks outdoors has been a new norm due to the COVID 19 pandemic as an initiative of controlling the spread of coronavirus. To reduce the risk of people being exposed to viruses, face masks were compulsory to be worn by Malaysians. However, there are people who refused to do so due to various reasons such as feeling lazy, uncomfortable, troublesome, and others, even the act of wearing a face mask is enforced by law. Therefore, it is essential to build a face mask detector to monitor automatically and ensure people are wearing masks correctly. The performance such as precision and response time of face mask detectors are important to support their application in the real-time working environment. The issue of performance enhancement in the form of adding more layers or implementing hybrid models such as spatial pyramid pooling (SPP) modules is increasing the complexity of the algorithm and making it bulky. The objective of this paper is to build a face mask detector by using the latest high-performance deep learning model, YOLOv4 and YOLOv5 together with MixUp technique which can contribute to high mean accuracy precision (mAP) and short inference time that suffice the requirements to be working in a real-time environment. This research conducted data sets collection and data annotation at the beginning stage of the algorithm, then MixUp technique was applied to the collected datasets to train the YOLOv4 and YOLOv5 using Google Colab. Next, the trained model was tested, and the performance was evaluated in terms of mAP using the average precision (AP) from the confusion matrix and inference time based on the time taken for prediction. The algorithm with the YOLOv5 model having slightly lower mAP than YOLOv4 but shorter training and inference time. However, both models able to detect and classify the input image to three classes included with-mask (1), without-mask (2), and incorrectly with-mask (3) with good performance
The prevention impact of the green algal extract against genetic toxicity and antioxidant enzyme alteration in the Mozambique tilapia
Get PDFAlgal studies are primary for ecological risk assessment and toxicology by evaluating lethal and sub-lethal toxic impacts of potential toxicants on inhabitants of numerous ecosystems. Dunaliella salina, a green marine alga, is characterized by its carotenoid accumulation and is widely used in many health and nutritional products. Our experiment was designed to evaluate algal extract's ability to inhibit genetic alterations induced by mutagen agents such as dioxin in the Mozambique tilapia. The expression of three stress genes was examined: heat shock protein 90 (Hsp90), CYP1A1 as one of the main cytochrome P450 enzymes, and metallothionein (MT). The study exhibited a characteristic sensitivity to metal treatments. Liver samples were collected from all fish to analyze bio-indicators, including superoxide dismutase (SOD), malondialdehyde (MDA), and reactive oxygen species (ROS). While gills samples were used for DNA fragmentation assay. Results showed that oxidative stress in the dioxin group's liver significantly changed indicators. However, the dioxin group significantly increased the SOD, MDA enzyme activities, and ROS formation. Interestingly, the genes Hsp90, CYP1A1, and MT expression were significantly down-regulated in Dunaliella salina groups. Nevertheless, DNA fragmentation in gill organs was affected by exposure to dioxin in fish. Thus, it was concluded that the methanolic extract of an isolated strain Dunaliella salina is effective against mutagen agent dioxin by inhibiting genetic alterations in fish organs with an antioxidant defense system to conquer oxidative damage
On reliability in downlink data dissemination over opportunistic multiple hops in UAV-assisted FANET
No full textUnmanned aerial vehicles (UAVs) acting as cooperative relays in FANETs are a viable way to improve the coverage and performance of current communication networks. Monitoring, surveillance, and telemetry applications are all possible with UAVs. The UAV-assisted cooperative relay network is investigated in a downlink communication scenario over a Nakagami-m fading environment, passing observations to a ground control station (GCS) for analysis. Decode-and-forward (DF) relaying and half-duplexed mode (HD) communication are considered to be used by the relaying UAVs. The use of an opportunistic constellation of UAVs to create a multi-hop serial link is discussed and contrasted to multiple dual-hop links operating in tandem. In the case of multiple dual-hop links, the maximal ratio combining (MRC) technique is being used to combine signals that are sent from the source to the destination via multiple intermediate relays, and this technique is compared to selection combining (SC). For single and multiple relays cases, analytical expressions for transmission times, end-to-end SNRs, and system outage probability are presented. Changing the link SNRs and observing system reliability in terms of probability of outage in various settings is used to investigate the impact of increasing the number of intermediate relays and channel information rates. To validate the analytical results, Monte Carlo simulations are used. The results show that multiple dual-hop links employing MRC perform better than other system settings, and that performance improves as the number of relays and channel state information (CSI) increases, but that the communication range is limited. Multi-hop serial communication can, however, facilitate range extension applications at the cost of diminished reliability. In FANET design, the tradeoffs presented by both configurations must be considered
Casson fluid convective flow in an accelerated microchannel with thermal radiation using the caputo fractional derivative
Get PDFThe effect of the Caputo fractional derivative in unsteady boundary layer Casson fluid flow in an accelerated microchannel is investigated. In the presence of thermal radiation, the partial differential equations that governed the problem are studied. Using appropriate dimensionless variables, fractional partial differential equations are translated into dimensionless governing equations. The equations are then transformed into linear ordinary differential equations and solved analytically using the Laplace transform technique. These modified equations are then solved using the proper method, and the result is obtained in the form of velocity and temperature profiles using the Zakian’s explicit formula approach. The influence of essential physical parameters on velocity and temperature profiles is investigated using graphical diagrams created with Mathcad software. It is found that the velocity and temperature profile increase as fractional parameter, and thermal radiation parameter increase. As Prandtl number increase, both profiles are decreasing. This result is crucial for understanding the fractional system of Casson fluid in microchannel
A systematic review and trend analysis of personal learning environments research
Get PDFThe concept of personal learning environments (PLEs) is relatively new and is continuously developing. Over the past decade, there has been a significant upsurge in the number of PLEs-related research. Nevertheless, there is a lack of recent systematic reviews and trend analysis covering many PLEs studies; to the best of our knowledge. Therefore, the current systematic review is significant and indispensable in reviewing journal articles that discussed PLEs between 2000 and 2020. We searched Web of Science, Scopus, Sciences Direct, JSTOR, Springer, Google Scholar, and IEEE Xplore for studies published in English without limit in location or time to retrieve accurate results. Trend graphics for the extracted themes were also analyzed using descriptive statistics in Excel. According to the defined inclusion criteria, one hundred forty-eight articles were selected for the analysis. This study reveals that literature on PLEs has progressed from 2000 to 2020; the majority of PLEs-related articles were published between 2011 and 2020, with the year 2013 having the highest number of published articles (17 articles), followed by 16 papers published in both years 2014 and 2017. We found that the published PLEs research originated from 46 countries; 26 (17.6%) were from Spain. The majority of the authors had education, computer science, information technology and engineering backgrounds. This review also showed that numerous platforms had been used in PLEs research, with Web 2.0 the most commonly used platform. We noted that the most common objectives of the included articles were PLEs custom system development, analysis of the PLEs, description of experiments, investigations, development of factor models, framework development, and examination. The most common theoretical perspectives in the published articles were self-regulated learning, self-directed learning, and constructivism. The current systematic review and trend analysis can become a guidance platform for researchers, educators, policymakers or even journal publishers for future research in PLEs research
Applications of mobile information processor edge-over-edge molecular wires with high-performance thermoelectric generators
Get PDFIf high-efficiency organic isotherm models for mobile processors can be found, a variety of energy harvesting devices, such as Peltier coolers composed of flexible and transparent thin-film materials, might be manufactured. The thermoelectric characteristics of three zinc porphyrins (ZnP) were studied. Theoretical analyses of electron transport across a potassium (Zn-Diphenyl porphyrin: Zn-DPP) molecular sandwiched between electrode surface with three distinct connections were investigated. The contribution of this research is to see what happens because once pyridine is added above the surface of the zinc-porphyrin skeleton, the "edge-over-edge"dimer created from stacked formed rings has a high electrical conductance, minimal exciton thermal conductance, and a large thermal diffusivity on the order of 300 V K1. At room temperature, these variables add up to a projected ZT 4 figure of merit, the greatest ZT for a single organic molecule ever seen. The stacked arrangement of the porphyrin rings causes low phonon thermal conductance, which delays phonon transport across the edge-over-edge molecule and increases the Seebeck coefficient, resulting in a higher ZT value