Search results for: multi-objective combinatorial optimization problem
8324 Heuristic Methods for the Capacitated Location- Allocation Problem with Stochastic Demand
Authors: Salinee Thumronglaohapun
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The proper number and appropriate locations of service centers can save cost, raise revenue and gain more satisfaction from customers. Establishing service centers is high-cost and difficult to relocate. In long-term planning periods, several factors may affect the service. One of the most critical factors is uncertain demand of customers. The opened service centers need to be capable of serving customers and making a profit although the demand in each period is changed. In this work, the capacitated location-allocation problem with stochastic demand is considered. A mathematical model is formulated to determine suitable locations of service centers and their allocation to maximize total profit for multiple planning periods. Two heuristic methods, a local search and genetic algorithm, are used to solve this problem. For the local search, five different chances to choose each type of moves are applied. For the genetic algorithm, three different replacement strategies are considered. The results of applying each method to solve numerical examples are compared. Both methods reach to the same best found solution in most examples but the genetic algorithm provides better solutions in some cases.Keywords: location-allocation problem, stochastic demand, local search, genetic algorithm
Procedia PDF Downloads 1248323 Shipboard Power Plant Design as Senior Design Project
Authors: Hesham Shaalan
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Senior design projects teach students many important skills. One of the major goals is to prepare students to apply effective problem-solving techniques to a problem that represents a real-world situation. This includes the ability to define the problem, compare alternative solutions, identify the best solution, and design the system. This paper describes the design of a shipboard power plant as a senior project in the Marine Engineering program at the U.S. Merchant Marine Academy. The design project was supervised by faculty members who guided a multidisciplinary group of seniors. The research project was sponsored by the Office of Naval Research. Each group of seniors focused on one of the main design aspects of the project, including the electric power system, nuclear power plant, ship hull design, and economics.Keywords: senior design project, shipboard power system, engineering education, marine engineering
Procedia PDF Downloads 838322 Analysis of Experimentally Designed Soundproof Gypsum Partition Wall's Sections in Terms of Structural Engineering
Authors: Abdulkerim Ilgun, Ahmad Javid Zia
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In developing countries, the urban populations are increasing rapidly and with this increment the residential areas are experiencing major problems. Construction of high-rise buildings in confined spaces is one of the most practical solutions for this problem. However, by living in high-rise buildings and sharing common residential areas, residents will face many problems. Irritating sound problem which is known as noise is one of the major problems mentioned above. The second most important problem is the weight of the high-rise buildings which makes the structure more vulnerable to earthquakes. To decrease earthquake loads it’s very important to decrease the weight of the buildings. To solve the problem of noise and keep the building weight at minimum level, experimentally designed soundproof gypsum partition wall which has optimum thickness has been used in high-rise story building and the results have been compared with ordinary brick partition walls. In this compression the effect of weights of soundproof gypsum walls and ordinary brick walls in accordance to structural engineering have been investigated.Keywords: cellubor, gypsum board, gypsum partition walls, light partition walls, noise, sound
Procedia PDF Downloads 3078321 Quantitative Risk Analysis for Major Subsystems and Project Success of a Highthrouput Satellite
Authors: Ibrahim Isa Ali (Pantami), Abdu Jaafaru Bambale, Abimbola Alale, Danjuma Ibrahim Ndihgihdah, Muhammad Alkali, Adamu Idris Umar, Babadoko Dantala Mohammed, Moshood Kareem Olawole
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This paper dwells on the risk management required for High throughput Satellite (HTS) project, and major subsystems that pertains to the improved performance and reliability of the spacecraft. The paper gives a clear picture of high‐throughput satellites (HTS) and the associated technologies with performances as they align and differ with the traditional geostationary orbit or Geosynchronous Equatorial Orbit (GEO) Communication Satellites. The paper also highlights critical subsystems and processes in project conceptualization and execution. The paper discusses the configuration of the payload. The need for optimization of resources for the HTS project and successful integration of critical subsystems for spacecraft requires implementation of risk analysis and mitigation from the preliminary design stage; Assembly, Integration and Test (AIT); Launch and in-orbit- Management stage.Keywords: AIT, HTS, in-orbit management, optimization
Procedia PDF Downloads 1038320 Experimental Design and Optimization of Diesel Oil Desulfurization Process by Adsorption Processes
Authors: M. Firoz Kalam, Wilfried Schuetz, Jan Hendrik Bredehoeft
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Thiophene sulfur compounds' removal from diesel oil by batch adsorption process using commercial powdered activated carbon was designed and optimized in two-level factorial design method. This design analysis was used to find out the effects of operating parameters directing the adsorption process, such as amount of adsorbent, temperature and stirring time. The desulfurization efficiency was considered the response or output variable. Results showed that the stirring time had the largest effects on sulfur removal efficiency as compared with other operating parameters and their interactions under the experimental ranges studied. A regression model was generated to observe the closeness between predicted and experimental values. The three-dimensional plots and contour plots of main factors were generated according to the regression results to observe the optimal points.Keywords: activated carbon, adsorptive desulfurization, factorial design, process optimization
Procedia PDF Downloads 1628319 Understanding Profit Shifting by Multinationals in the Context of Cross-Border M&A: A Methodological Exploration
Authors: Michal Friedrich
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Cross-border investment has never been easier than in today’s global economy. Despite recent initiatives tightening the international tax landscape, profit shifting and tax optimization by multinational entities (MNEs) in the context of cross-border M&A remain persistent and complex phenomena that warrant in-depth exploration. By synthesizing the outcomes of existing research, this study aims to first provide a methodological framework for identifying MNEs’ profit-shifting behavior and quantifying its fiscal impacts via various macroeconomic and microeconomic approaches. The study also proposes additional methods and qualitative/quantitative measures for extracting insight into the profit shifting behavior of MNEs in the context of their M&A activities at industry and entity levels. To develop the proposed methods, this study applies the knowledge of international tax laws and known profit shifting conduits (incl. dividends, interest, and royalties) on several model cases/types of cross-border acquisitions and post-acquisition integration activities by MNEs and highlights important factors that encourage or discourage tax optimization. Follow-up research is envisaged to apply the methods outlined in this study on published data on real-world M&A transactions to gain practical country-by-country, industry and entity-level insights. In conclusion, this study seeks to contribute to the ongoing discourse on profit shifting by providing a methodological toolkit for exploring profit shifting tendencies MNEs in connection with their M&A activities and to serve as a backbone for further research. The study is expected to provide valuable insight to policymakers, tax authorities, and tax professionals alike.Keywords: BEPS, cross-border M&A, international taxation, profit shifting, tax optimization
Procedia PDF Downloads 698318 Modeling of Leaks Effects on Transient Dispersed Bubbly Flow
Authors: Mohand Kessal, Rachid Boucetta, Mourad Tikobaini, Mohammed Zamoum
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Leakage problem of two-component fluids flow is modeled for a transient one-dimensional homogeneous bubbly flow and developed by taking into account the effect of a leak located at the middle point of the pipeline. The corresponding three conservation equations are numerically resolved by an improved characteristic method. The obtained results are explained and commented in terms of physical impact on the flow parameters.Keywords: fluid transients, pipelines leaks, method of characteristics, leakage problem
Procedia PDF Downloads 4798317 GPS Signal Correction to Improve Vehicle Location during Experimental Campaign
Authors: L. Della Ragione, G. Meccariello
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In recent years the progress of the automobile industry in Italy in the field of reduction of emissions values is very remarkable. Nevertheless, their evaluation and reduction is a key problem, especially in the cities, which account for more than 50% of world population. In this paper we dealt with the problem of describing a quantitative approach for the reconstruction of GPS coordinates and altitude, in the context of correlation study between driving cycles / emission / geographical location, during an experimental campaign realized with some instrumented cars.Keywords: air pollution, driving cycles, GPS signal, vehicle location
Procedia PDF Downloads 4288316 A Hybrid Distributed Algorithm for Solving Job Shop Scheduling Problem
Authors: Aydin Teymourifar, Gurkan Ozturk
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In this paper, a distributed hybrid algorithm is proposed for solving the job shop scheduling problem. The suggested method executes different artificial neural networks, heuristics and meta-heuristics simultaneously on more than one machine. The neural networks are used to control the constraints of the problem while the meta-heuristics search the global space and the heuristics are used to prevent the premature convergence. To attain an efficient distributed intelligent method for solving big and distributed job shop scheduling problems, Apache Spark and Hadoop frameworks are used. In the algorithm implementation and design steps, new approaches are applied. Comparison between the proposed algorithm and other efficient algorithms from the literature shows its efficiency, which is able to solve large size problems in short time.Keywords: distributed algorithms, Apache Spark, Hadoop, job shop scheduling, neural network
Procedia PDF Downloads 3878315 Human Errors in IT Services, HFACS Model in Root Cause Categorization
Authors: Kari Saarelainen, Marko Jantti
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IT service trending of root causes of service incidents and problems is an important part of proactive problem management and service improvement. Human error related root causes are an important root cause category also in IT service management, although it’s proportion among root causes is smaller than in the other industries. The research problem in this study is: How root causes of incidents related to human errors should be categorized in an ITSM organization to effectively support service improvement. Categorization based on IT service management processes and based on Human Factors Analysis and Classification System (HFACS) taxonomy was studied in a case study. HFACS is widely used in human error root cause categorization across many industries. Combining these two categorization models in a two dimensional matrix was found effective, yet impractical for daily work.Keywords: IT service management, ITIL, incident, problem, HFACS, swiss cheese model
Procedia PDF Downloads 4898314 Molecular Signaling Involved in the 'Benzo(a)Pyrene' Induced Germ Cell DNA Damage and Apoptosis: Possible Protection by Natural Aryl Hydrocarbon Receptor Antagonist and Anti-Tumor Agent
Authors: Kuladip Jana
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Benzo(a)pyrene [B(a)P] is an environmental toxicant present mostly in cigarette smoke and car exhaust, is an aryl hydrocarbon receptor (AhR) ligand that exerts its toxic effects on both male and female reproductive systems. In this study, the effect of B(a)P at different doses (0.1, 0.25, 0.5, 1 and 5 mg /kg body weight) was studied on male reproductive system of rat. A significant decrease in cauda epididymal sperm count and motility along with the presence of sperm head abnormalities and altered epididymal and testicular histology were documented following B(a)P treatment. B(a)P treatment resulted apoptotic sperm cells as observed by TUNEL and Annexin V-PI assay with increased ROS, altered sperm mitochondrial membrane potential (ΔΨm) with a simultaneous decrease in the activity of antioxidant enzymes and GSH status. TUNEL positive apoptotic cells also observed in testis as well as isolated germ and Leydig cells following B(a)P exposure. Western Blot analysis revealed the activation of p38MAPK, cytosolic translocation of cytochrome-c, up-regulation of Bax and inducible nitric oxide synthase (iNOS) with cleavage of PARP and down-regulation of BCl2 in testis upon B(a)P treatment. The protein and mRNA levels of testicular key steroidogenesis regulatory proteins like StAR, cytochrome P450 IIA1 (CYPIIA1), 3β HSD, 17β HSD showed a significant decrease in a dose dependent manner while an increase in the expression of cytochrome P450 1A1 (CYP1A1), Aryl hydrocarbon Receptor (AhR), active caspase- 9 and caspase- 3 following B(a)P exposure. We conclude that exposure of benzo(a)pyrene caused testicular gamatogenic and steroidogenic disorders by induction of oxidative stress, inhibition of StAR and other steroidogenic enzymes along with activation of p38MAPK and initiated caspase-3 mediated germ and Leydig cell apoptosis.The possible protective role of naturally occurring phytochemicals against B(a)P induced testicular toxicity needs immediate consideration. Curcumin and resveratrol separately were found to protect against B(a)P induced germ cell apoptosis, and their combinatorial effect was more significant. Our present study in isolated testicular germ cell population from adult male Wistar rats, highlighted their synergistic protective effect against B(a)P induced germ cell apoptosis. Curcumin-resveratrol co-treatment decreased the expression of pro-apoptotic proteins like cleaved caspase 3,8,9, cleaved PARP, Apaf1, FasL, tBid. Curcumin-resveratrol co-treatment decreased Bax/Bcl2 ratio, mitochondria to cytosolic translocation of cytochrome c and activated the survival protein Akt. Curcumin-resveratrol decreased the expression of p53 dependent apoptotic genes like Fas, FasL, Bax, Bcl2, Apaf1.Curcumin-resveratrol co-treatment thus prevented B(a)P induced germ cell apoptosis. B(a)P induced testicular ROS generation and oxidative stress were significantly ameliorated with curcumin and resveratrol. Curcumin-resveratrol co-treatment prevented B(a)P induced nuclear translocation of AhR and CYP1A1 production. The combinatorial treatment significantly inhibited B(a)P induced ERK 1/2, p38 MAPK and JNK 1/2 activation. B(a)P treatment increased the expression of p53 and its phosphorylation (p53 ser 15). Curcumin-resveratrol co-treatment significantly decreased p53 level and its phosphorylation (p53 ser 15). The study concludes that curcumin-resveratrol synergistically modulated MAPKs and p53, prevented oxidative stress, regulated the expression of pro and anti-apoptotic proteins as well as the proteins involved in B(a)P metabolism thus protected germ cells from B(a)P induced apoptosis.Keywords: benzo(a)pyrene, germ cell, apoptosis, oxidative stress, resveratrol, curcumin
Procedia PDF Downloads 2608313 Development of Flipped Classroom in Chemistry on 'Acid-Base' for Enrichment Science Classroom Students
Authors: Waratthaya Maneerattana, Piyarat Dornbundit
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The study aimed to develop flipped classroom in Chemistry on ‘acid-base’ for high school students and study efficiency of students on academic achievement and problem-solving skills. The evaluating result from the experts showed that developed flipped classroom was ranked in high score level. The flipped classroom efficiency E1/E2 was higher than the criteria of 70/70. The flipped classroom was used by 24 students in grade 11 in the second semester of the academic year 2016 at Bodindecha (Sing Singhaseni) School. Sampling group was chosen using a purposive sampling approach. The results revealed that academic achievement and problem solving skills of students after studying flipped classroom was significantly higher at .05 level.Keywords: flipped classroom, acid-base, academic achievement, problem solving skill
Procedia PDF Downloads 3148312 Cluster Analysis and Benchmarking for Performance Optimization of a Pyrochlore Processing Unit
Authors: Ana C. R. P. Ferreira, Adriano H. P. Pereira
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Given the frequent variation of mineral properties throughout the Araxá pyrochlore deposit, even if a good homogenization work has been carried out before feeding the processing plants, an operation with quality and performance’s high variety standard is expected. These results could be improved and standardized if the blend composition parameters that most influence the processing route are determined, and then the types of raw materials are grouped by them, finally presenting a great reference with operational settings for each group. Associating the physical and chemical parameters of a unit operation through benchmarking or even an optimal reference of metallurgical recovery and product quality reflects in the reduction of the production costs, optimization of the mineral resource, and guarantee of greater stability in the subsequent processes of the production chain that uses the mineral of interest. Conducting a comprehensive exploratory data analysis to identify which characteristics of the ore are most relevant to the process route, associated with the use of Machine Learning algorithms for grouping the raw material (ore) and associating these with reference variables in the process’ benchmark is a reasonable alternative for the standardization and improvement of mineral processing units. Clustering methods through Decision Tree and K-Means were employed, associated with algorithms based on the theory of benchmarking, with criteria defined by the process team in order to reference the best adjustments for processing the ore piles of each cluster. A clean user interface was created to obtain the outputs of the created algorithm. The results were measured through the average time of adjustment and stabilization of the process after a new pile of homogenized ore enters the plant, as well as the average time needed to achieve the best processing result. Direct gains from the metallurgical recovery of the process were also measured. The results were promising, with a reduction in the adjustment time and stabilization when starting the processing of a new ore pile, as well as reaching the benchmark. Also noteworthy are the gains in metallurgical recovery, which reflect a significant saving in ore consumption and a consequent reduction in production costs, hence a more rational use of the tailings dams and life optimization of the mineral deposit.Keywords: mineral clustering, machine learning, process optimization, pyrochlore processing
Procedia PDF Downloads 1438311 Joint Replenishment and Heterogeneous Vehicle Routing Problem with Cyclical Schedule
Authors: Ming-Jong Yao, Chin-Sum Shui, Chih-Han Wang
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This paper is developed based on a real-world decision scenario that an industrial gas company that applies the Vendor Managed Inventory model and supplies liquid oxygen with a self-operated heterogeneous vehicle fleet to hospitals in nearby cities. We name it as a Joint Replenishment and Heterogeneous Vehicle Routing Problem with Cyclical Schedule and formulate it as a non-linear mixed-integer linear programming problem which simultaneously determines the length of the planning cycle (PC), the length of the replenishment cycle and the dates of replenishment for each customer and the vehicle routes of each day within PC, such that the average daily operation cost within PC, including inventory holding cost, setup cost, transportation cost, and overtime labor cost, is minimized. A solution method based on genetic algorithm, embedded with an encoding and decoding mechanism and local search operators, is then proposed, and the hash function is adopted to avoid repetitive fitness evaluation for identical solutions. Numerical experiments demonstrate that the proposed solution method can effectively solve the problem under different lengths of PC and number of customers. The method is also shown to be effective in determining whether the company should expand the storage capacity of a customer whose demand increases. Sensitivity analysis of the vehicle fleet composition shows that deploying a mixed fleet can reduce the daily operating cost.Keywords: cyclic inventory routing problem, joint replenishment, heterogeneous vehicle, genetic algorithm
Procedia PDF Downloads 878310 Improving Creative Problem Solving for Teams through a Web-Based Peer Review System
Authors: JungYeon Park, Jooyong Park
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Brainstorming and discussion are widely used around the world as formal techniques of collaborative creative problem solving. This study investigated whether a web-based peer review system would improve collaborative creative problem solving. In order to assess the efficiency of using web-based peer review system before brainstorming and discussion, we conducted a between-group design study for two conditions (a web-based peer review system vs. face-to-face brainstorming only) using two different scenarios. One hundred and twenty participants were divided into teams of four and randomly assigned to one of the four conditions. The participants were given problems for them to solve. The participants in the experimental group first generated ideas independently for 20 minutes and wrote down their ideas. Afterwards, they reviewed the list of ideas of their peers and gave and received feedback for 10 minutes. These activities were performed on-line. The last activity was face-to-face brain-storming and discussion for 30 minutes. In contrast, the control group participated in brainstorming and discussion for 60 minutes. The quantity and the quality of ideas were measured as dependent variables of creative problem solving. Two evaluators rated the quantity and quality of the proposed ideas. Inter-rater agreement rate was good or strong. The results showed that both the average number of unique ideas and the average quality of ideas generated for the experimental condition were significantly higher than those for the control condition in both scenarios. The results of this study support the hypothesis that collaborative creative problem solving is enhanced when individuals write their thoughts individually and review ideas written by peers before face-to-face brainstorming and discussion. The present study provides preliminary evidence that a web-based peer review system can be instrumental in improving creative problem solving for teams. This system also offers an effective means to quantify the contribution of each member in collaborative team activity. We are planning to replicate these results in real-life situations.Keywords: brainstorming, creative problem solving, peer-review, team efficiency
Procedia PDF Downloads 1588309 Credit Card Fraud Detection with Ensemble Model: A Meta-Heuristic Approach
Authors: Gong Zhilin, Jing Yang, Jian Yin
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The purpose of this paper is to develop a novel system for credit card fraud detection based on sequential modeling of data using hybrid deep learning models. The projected model encapsulates five major phases are pre-processing, imbalance-data handling, feature extraction, optimal feature selection, and fraud detection with an ensemble classifier. The collected raw data (input) is pre-processed to enhance the quality of the data through alleviation of the missing data, noisy data as well as null values. The pre-processed data are class imbalanced in nature, and therefore they are handled effectively with the K-means clustering-based SMOTE model. From the balanced class data, the most relevant features like improved Principal Component Analysis (PCA), statistical features (mean, median, standard deviation) and higher-order statistical features (skewness and kurtosis). Among the extracted features, the most optimal features are selected with the Self-improved Arithmetic Optimization Algorithm (SI-AOA). This SI-AOA model is the conceptual improvement of the standard Arithmetic Optimization Algorithm. The deep learning models like Long Short-Term Memory (LSTM), Convolutional Neural Network (CNN), and optimized Quantum Deep Neural Network (QDNN). The LSTM and CNN are trained with the extracted optimal features. The outcomes from LSTM and CNN will enter as input to optimized QDNN that provides the final detection outcome. Since the QDNN is the ultimate detector, its weight function is fine-tuned with the Self-improved Arithmetic Optimization Algorithm (SI-AOA).Keywords: credit card, data mining, fraud detection, money transactions
Procedia PDF Downloads 1318308 Proposal of a Model Supporting Decision-Making Based on Multi-Objective Optimization Analysis on Information Security Risk Treatment
Authors: Ritsuko Kawasaki (Aiba), Takeshi Hiromatsu
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Management is required to understand all information security risks within an organization, and to make decisions on which information security risks should be treated in what level by allocating how much amount of cost. However, such decision-making is not usually easy, because various measures for risk treatment must be selected with the suitable application levels. In addition, some measures may have objectives conflicting with each other. It also makes the selection difficult. Moreover, risks generally have trends and it also should be considered in risk treatment. Therefore, this paper provides the extension of the model proposed in the previous study. The original model supports the selection of measures by applying a combination of weighted average method and goal programming method for multi-objective analysis to find an optimal solution. The extended model includes the notion of weights to the risks, and the larger weight means the priority of the risk.Keywords: information security risk treatment, selection of risk measures, risk acceptance, multi-objective optimization
Procedia PDF Downloads 4618307 Nonstationary Waves Excited by the Rigid Cylinder in Elastic Medium
Authors: Tukeaban Hasanova, Jamila Imamalieva
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By the operational method, the problem on two-dimensional wave propagation in elastic medium excited by the round cylinder is solved. An analytical solution responding to instantaneous application of speed to the inclusion at its subsequent change is constructed. The two-dimensional problem on wave propagation in an elastic medium is considered.Keywords: cylinder, inclusion, wave, elastic medium, speed
Procedia PDF Downloads 1638306 Optimization of High Flux Density Design for Permanent Magnet Motor
Authors: Dong-Woo Kang
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This paper presents an optimal magnet shape of a spoke-shaped interior permanent magnet synchronous motor by using ferrite magnets. Generally, the permanent magnet motor used the ferrite magnets has lower output power and efficiency than a rare-earth magnet motor, because the ferrite magnet has lower magnetic energy than the rare-earth magnet. Nevertheless, the ferrite magnet motor is used to many industrial products owing to cost effectiveness. In this paper, the authors propose a high power density design of the ferrite permanent magnet synchronous motor. Furthermore, because the motor design has to be taken a manufacturing process into account, the design is simulated by using the finite element method for analyzing the demagnetization, the magnetizing, and the structure stiffness. Especially, the magnet shape and dimensions are decided for satisfying these properties. Finally, the authors design an optimal motor for applying our system. That final design is manufactured and evaluated from experimentations.Keywords: demagnetization, design optimization, magnetic analysis, permanent magnet motors
Procedia PDF Downloads 3778305 Understanding Evolutionary Algorithms through Interactive Graphical Applications
Authors: Javier Barrachina, Piedad Garrido, Manuel Fogue, Julio A. Sanguesa, Francisco J. Martinez
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It is very common to observe, especially in Computer Science studies that students have difficulties to correctly understand how some mechanisms based on Artificial Intelligence work. In addition, the scope and limitations of most of these mechanisms are usually presented by professors only in a theoretical way, which does not help students to understand them adequately. In this work, we focus on the problems found when teaching Evolutionary Algorithms (EAs), which imitate the principles of natural evolution, as a method to solve parameter optimization problems. Although this kind of algorithms can be very powerful to solve relatively complex problems, students often have difficulties to understand how they work, and how to apply them to solve problems in real cases. In this paper, we present two interactive graphical applications which have been specially designed with the aim of making Evolutionary Algorithms easy to be understood by students. Specifically, we present: (i) TSPS, an application able to solve the ”Traveling Salesman Problem”, and (ii) FotEvol, an application able to reconstruct a given image by using Evolution Strategies. The main objective is that students learn how these techniques can be implemented, and the great possibilities they offer.Keywords: education, evolutionary algorithms, evolution strategies, interactive learning applications
Procedia PDF Downloads 3388304 Transit Network Design Problem Issues and Challenges
Authors: Mahmoud Owais
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Public Transit (P.T) is very important means to reduce traffic congestion, to improve urban environmental conditions and consequently affects people social lives. Planning, designing and management of P.T are the key issues for offering a competitive mode that can compete with the private transportation. These transportation planning, designing and management issues are addressed in the Transit Network Design Problem (TNDP). It deals with a complete hierarchy of decision making process. It includes strategic, tactical and operational decisions. The main body of TNDP is two stages, namely; route design stage and frequency setting. The TNDP is extensively studied in the last five decades; however the research gate is still widely open due to its many practical and modeling challenges. In this paper, a comprehensive background is given to illustrate the issues and challenges related to the TNDP to help in directing the incoming researches towards the untouched areas of the problem.Keywords: frequency setting, network design, transit planning, urban planning
Procedia PDF Downloads 3858303 Modelling of Relocation and Battery Autonomy Problem on Electric Cars Sharing Dynamic by Using Discrete Event Simulation and Petri Net
Authors: Taha Benarbia, Kay W. Axhausen, Anugrah Ilahi
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Electric car sharing system as ecologic transportation increasing in the world. The complexity of managing electric car sharing systems, especially one-way trips and battery autonomy have direct influence to on supply and demand of system. One must be able to precisely model the demand and supply of these systems to better operate electric car sharing and estimate its effect on mobility management and the accessibility that it provides in urban areas. In this context, our work focus to develop performances optimization model of the system based on discrete event simulation and stochastic Petri net. The objective is to search optimal decisions and management parameters of the system in order to fulfil at best demand while minimizing undesirable situations. In this paper, we present new model of electric cars sharing with relocation based on monitoring system. The proposed approach also help to precise the influence of battery charging level on the behaviour of system as important decision parameter of this complex and dynamical system.Keywords: electric car-sharing systems, smart mobility, Petri nets modelling, discrete event simulation
Procedia PDF Downloads 1838302 A Mixing Matrix Estimation Algorithm for Speech Signals under the Under-Determined Blind Source Separation Model
Authors: Jing Wu, Wei Lv, Yibing Li, Yuanfan You
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The separation of speech signals has become a research hotspot in the field of signal processing in recent years. It has many applications and influences in teleconferencing, hearing aids, speech recognition of machines and so on. The sounds received are usually noisy. The issue of identifying the sounds of interest and obtaining clear sounds in such an environment becomes a problem worth exploring, that is, the problem of blind source separation. This paper focuses on the under-determined blind source separation (UBSS). Sparse component analysis is generally used for the problem of under-determined blind source separation. The method is mainly divided into two parts. Firstly, the clustering algorithm is used to estimate the mixing matrix according to the observed signals. Then the signal is separated based on the known mixing matrix. In this paper, the problem of mixing matrix estimation is studied. This paper proposes an improved algorithm to estimate the mixing matrix for speech signals in the UBSS model. The traditional potential algorithm is not accurate for the mixing matrix estimation, especially for low signal-to noise ratio (SNR).In response to this problem, this paper considers the idea of an improved potential function method to estimate the mixing matrix. The algorithm not only avoids the inuence of insufficient prior information in traditional clustering algorithm, but also improves the estimation accuracy of mixing matrix. This paper takes the mixing of four speech signals into two channels as an example. The results of simulations show that the approach in this paper not only improves the accuracy of estimation, but also applies to any mixing matrix.Keywords: DBSCAN, potential function, speech signal, the UBSS model
Procedia PDF Downloads 1358301 Drug Therapy Problem and Its Contributing Factors among Pediatric Patients with Infectious Diseases Admitted to Jimma University Medical Center, South West Ethiopia: Prospective Observational Study
Authors: Desalegn Feyissa Desu
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Drug therapy problem is a significant challenge to provide high quality health care service for the patients. It is associated with morbidity, mortality, increased hospital stay, and reduced quality of life. Moreover, pediatric patients are quite susceptible to drug therapy problems. Thus this study aimed to assess drug therapy problem and its contributing factors among pediatric patients diagnosed with infectious disease admitted to pediatric ward of Jimma university medical center, from April 1 to June 30, 2018. Prospective observational study was conducted among pediatric patients with infectious disease admitted from April 01 to June 30, 2018. Drug therapy problems were identified by using Cipolle’s and strand’s drug related problem classification method. Patient’s written informed consent was obtained after explaining the purpose of the study. Patient’s specific data were collected using structured questionnaire. Data were entered into Epi data version 4.0.2 and then exported to statistical software package version 21.0 for analysis. To identify predictors of drug therapy problems occurrence, multiple stepwise backward logistic regression analysis was done. The 95% CI was used to show the accuracy of data analysis and statistical significance was considered at p-value < 0.05. A total of 304 pediatric patients were included in the study. Of these, 226(74.3%) patients had at least one drug therapy problem during their hospital stay. A total of 356 drug therapy problems were identified among two hundred twenty six patients. Non-compliance (28.65%) and dose too low (27.53%) were the most common type of drug related problems while disease comorbidity [AOR=3.39, 95% CI= (1.89-6.08)], Polypharmacy [AOR=3.16, 95% CI= (1.61-6.20)] and more than six days stay in hospital [AOR=3.37, 95% CI= (1.71-6.64) were independent predictors of drug therapy problem occurrence. Drug therapy problems were common in pediatric patients with infectious disease in the study area. Presence of comorbidity, polypharmacy and prolonged hospital stay were the predictors of drug therapy problem in study area. Therefore, to overcome the significant gaps in pediatric pharmaceutical care, clinical pharmacists, Pediatricians, and other health care professionals have to work in collaboration.Keywords: drug therapy problem, pediatric, infectious disease, Ethiopia
Procedia PDF Downloads 1538300 Redefining Infrastructure as Code Orchestration Using AI
Authors: Georges Bou Ghantous
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This research delves into the transformative impact of Artificial Intelligence (AI) on Infrastructure as Code (IaaC) practices, specifically focusing on the redefinition of infrastructure orchestration. By harnessing AI technologies such as machine learning algorithms and predictive analytics, organizations can achieve unprecedented levels of efficiency and optimization in managing their infrastructure resources. AI-driven IaaC introduces proactive decision-making through predictive insights, enabling organizations to anticipate and address potential issues before they arise. Dynamic resource scaling, facilitated by AI, ensures that infrastructure resources can seamlessly adapt to fluctuating workloads and changing business requirements. Through case studies and best practices, this paper sheds light on the tangible benefits and challenges associated with AI-driven IaaC transformation, providing valuable insights for organizations navigating the evolving landscape of digital infrastructure management.Keywords: artificial intelligence, infrastructure as code, efficiency optimization, predictive insights, dynamic resource scaling, proactive decision-making
Procedia PDF Downloads 348299 Optimal Load Control Strategy in the Presence of Stochastically Dependent Renewable Energy Sources
Authors: Mahmoud M. Othman, Almoataz Y. Abdelaziz, Yasser G. Hegazy
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This paper presents a load control strategy based on modification of the Big Bang Big Crunch optimization method. The proposed strategy aims to determine the optimal load to be controlled and the corresponding time of control in order to minimize the energy purchased from substation. The presented strategy helps the distribution network operator to rely on the renewable energy sources in supplying the system demand. The renewable energy sources used in the presented study are modeled using the diagonal band Copula method and sequential Monte Carlo method in order to accurately consider the multivariate stochastic dependence between wind power, photovoltaic power and the system demand. The proposed algorithms are implemented in MATLAB environment and tested on the IEEE 37-node feeder. Several case studies are done and the subsequent discussions show the effectiveness of the proposed algorithm.Keywords: big bang big crunch, distributed generation, load control, optimization, planning
Procedia PDF Downloads 3458298 Pattern Synthesis of Nonuniform Linear Arrays Including Mutual Coupling Effects Based on Gaussian Process Regression and Genetic Algorithm
Authors: Ming Su, Ziqiang Mu
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This paper proposes a synthesis method for nonuniform linear antenna arrays that combine Gaussian process regression (GPR) and genetic algorithm (GA). In this method, the GPR model can be used to calculate the array radiation pattern in the presence of mutual coupling effects, and then the GA is used to optimize the excitations and locations of the elements so as to generate the desired radiation pattern. In this paper, taking a 9-element nonuniform linear array as an example and the desired radiation pattern corresponding to a Chebyshev distribution as the optimization objective, optimize the excitations and locations of the elements. Finally, the optimization results are verified by electromagnetic simulation software CST, which shows that the method is effective.Keywords: nonuniform linear antenna arrays, GPR, GA, mutual coupling effects, active element pattern
Procedia PDF Downloads 1108297 Optimization of Flip Bucket Dents in Order to Reduce Scour Hole Depth (Plunge Pool) Using a Comprehensive Physical Model
Authors: Majid Galoie, Khodadad Safavi, Abdolreza Karami Nejad, Reza Roshan
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Scour downstream of a flip bucket in a plunge pool is caused by impingement of water jet force. In order to reduce this force and consequently reduce scour hole depth, flip buckets may equip by dents. The minimum scour hole depth might be occurred by optimization of dents (number, shape, placement) on flip buckets. In this study, a comprehensive physical model has been developed and various options for dents have been investigated. The experimental data for each dent option such as scour hole depth, angle of impingement jet, piezometric pressure in tail-water and jet trajectory have been measured for various discharges. Finally, the best option can be found by analysis of the experimental results which has been expressed in this paper.Keywords: scouring process, plunge pool, scour hole depth, physical model, flip bucket
Procedia PDF Downloads 3948296 Synergistic Impacts and Optimization of Gas Flow Rate, Concentration of CO2, and Light Intensity on CO2 Biofixation in Wastewater Medium by Chlorella vulgaris
Authors: Ahmed Arkoazi, Hussein Znad, Ranjeet Utikar
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The synergistic impact and optimization of gas flow rate, concentration of CO2, and light intensity on CO2 biofixation rate were investigated using wastewater as a medium to cultivate Chlorella vulgaris under different conditions (gas flow rate 1-8 L/min), CO2 concentration (0.03-7%), and light intensity (150-400 µmol/m2.s)). Response Surface Methodology and Box-Behnken experimental Design were applied to find optimum values for gas flow rate, CO2 concentration, and light intensity. The optimum values of the three independent variables (gas flow rate, concentration of CO2, and light intensity) and desirability were 7.5 L/min, 3.5%, and 400 µmol/m2.s, and 0.904, respectively. The highest amount of biomass produced and CO2 biofixation rate at optimum conditions were 5.7 g/L, 1.23 gL-1d-1, respectively. The synergistic effect between gas flow rate and concentration of CO2, and between gas flow rate and light intensity was significant on the three responses, while the effect between CO2 concentration and light intensity was less significant on CO2 biofixation rate. The results of this study could be highly helpful when using microalgae for CO2 biofixation in wastewater treatment.Keywords: bubble column reactor, gas holdup, hydrodynamics, sparger
Procedia PDF Downloads 1448295 Intelligent Staff Scheduling: Optimizing the Solver with Tabu Search
Authors: Yu-Ping Chiu, Dung-Ying Lin
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Traditional staff scheduling methods, relying on employee experience, often lead to inefficiencies and resource waste. The challenges of transferring scheduling expertise and adapting to changing labor regulations further complicate this process. Manual approaches become increasingly impractical as companies accumulate complex scheduling rules over time. This study proposes an algorithmic optimization approach to address these issues, aiming to expedite scheduling while ensuring strict compliance with labor regulations and company policies. The method focuses on generating optimal schedules that minimize weighted company objectives within a compressed timeframe. Recognizing the limitations of conventional commercial software in modeling and solving complex real-world scheduling problems efficiently, this research employs Tabu Search with both long-term and short-term memory structures. The study will present numerical results and managerial insights to demonstrate the effectiveness of this approach in achieving intelligent and efficient staff scheduling.Keywords: intelligent memory structures, mixed integer programming, meta-heuristics, staff scheduling problem, tabu search
Procedia PDF Downloads 25