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دسترسی آزاد مقاله
1 - آزمون روش شارپ تجدید‌نظر‌شده مبتنی بر ارزش در معرض خطر جهت ارزیابی عملکرد (شرکت‌های بورس اوراق بهادار تهران)
سیدرضا میرغفاریدر این مقاله، شاخص جدیدی بنام شارپ تجدید‌نظر‌شده مبتنی بر ارزش در معرض خطر به عنوان یک شاخص قابل قبول جهت ارزیابی عملکرد شرکت‌های فعال در بازار سرمایه معرفی شده است. ارزش در معرض خطر به دلیل دارا بودن ویژگی‌های منحصربه‌فرد و همچنین به دلیل اقبال نهادهای مالی و بین‌المل چکیده کاملدر این مقاله، شاخص جدیدی بنام شارپ تجدید‌نظر‌شده مبتنی بر ارزش در معرض خطر به عنوان یک شاخص قابل قبول جهت ارزیابی عملکرد شرکت‌های فعال در بازار سرمایه معرفی شده است. ارزش در معرض خطر به دلیل دارا بودن ویژگی‌های منحصربه‌فرد و همچنین به دلیل اقبال نهادهای مالی و بین‌المللی دنیا جهت ارزیابی ریسک، در این شاخص به عنوان یک نو‌آوری ابزاری مورد استفاده قرار گرفته است. در تحقیق حاضر، ارزیابی عملکرد شرکت‌های سرمایه‌گذاری و شرکت‌های فلزات اساسی بورس اوراق بهادار تهران با دو روش محاسبه شاخص شارپ و شاخص شارپ تجدید‌نظر‌شده در دوره زمانی سال 1385 تا 1389 مورد مقایسه و آزمون قرار گرفته است. نتایج این تحقیق نشان می‌دهد که در شرکت‌هایی که پرتفوی متنوعی دارند (شرکت‌های سرمایه‌گذاری) استفاده از شاخص شارپ یا شارپ تجدید‌نظر شده، تفاوت معناداری در رتبه‌بندی شرکت‌ها ایجاد نمی‌کند. در مورد شرکت‌هایی که پرتفوی ندارند (شرکت‌های تولیدکننده فلزات اساسی) و یا پرتفوی متنوعی ندارند به‌رغم مشاهده تفاوت ظاهری در رتبه‌بندی، این تفاوت از نظر آماری معنادار نیست. پرونده مقاله -
دسترسی آزاد مقاله
2 - Scheduling of Multiple Autonomous Guided Vehicles for an Assembly Line Using Minimum Cost Network Flow
Hamed FazlollahtabarThis paper proposed a parallel automated assembly line system to produce multiple products having multiple autonomous guided vehicles (AGVs). Several assembly lines are configured to produce multiple products in which the technologies of machines are shared among the as چکیده کاملThis paper proposed a parallel automated assembly line system to produce multiple products having multiple autonomous guided vehicles (AGVs). Several assembly lines are configured to produce multiple products in which the technologies of machines are shared among the assembly lines when required. The transportation between the stations in an assembly line (intra assembly line) and among stations in different assembly lines (inter assembly line) are performed using AGVs. Scheduling of AGVs to service the assembly lines and the corresponding stations are purposed. In the proposed problem the assignment of multiple AGVs to different assembly lines and the stations are performed using minimum-cost network flow (MCF). It optimizes weighted completion time of tasks for each short-term window by formulating the task and resource assignment problem as MCF problem during each short-term scheduling window. پرونده مقاله -
دسترسی آزاد مقاله
3 - A Job Shop Scheduling and Location of Battery Charging Storage for the Automated Guided Vehicles (AGVs)
Saeed Dehnavi-Arani Ali Sabaghian Mehdi FazliWhen the Automated Guided Vehicles (AGVs) are transferring the parts from one machine to another in a job shop environment, it is possible that AGVsstopon their guidepaths since their batteries are discharged.Consequently, it is essential to establish at least one Batte چکیده کاملWhen the Automated Guided Vehicles (AGVs) are transferring the parts from one machine to another in a job shop environment, it is possible that AGVsstopon their guidepaths since their batteries are discharged.Consequently, it is essential to establish at least one Battery Charging Storage (BCS) to replace full batteries with empty batteries for the stopped AGVs. Due to non-predictable routes for AGVs in the manufacturing systems, to find the best place toestablish the BCS can impact performance of the system. In this paper, anintegrated mathematical modelof job shop and AGV schedulingwith respect tothe location of a BCS is proposed. The proposed nonlinear model is transformed into a linear form to beefficiently solvedin GAMS software. Finally, several numerical examplesare presented to test the validity of the proposed mathematical model.The results show that the optimal cost and location of BCS can be obtained with respect to the number of AGVs, machines, parts, and other problem parameters. In addition, it is concluded that the increasing number of AGVs in a manufacturing systemcannot be always a suitable policy for reducing the cost because in such conditions.Further to that, the conflict of AGVs may increase leading tothe increase of the makespan. In other words, following the optimal point, increasing AGVs leads to the increase in costs. پرونده مقاله -
دسترسی آزاد مقاله
4 - A Mathematical Model for Multiple-Load AGVs in Tandem Layout
Behnam Rahimikelarijani Mohammad Saidi-Mehrabad Farnaz BarzinpourReducing cost of material handling has been a big challenge for companies. Flexible manufacturing system employed automated guided vehicles (AGV) to maintain efficiency and flexibility. This paper presents a new non-linear mathematical programming model to group n machi چکیده کاملReducing cost of material handling has been a big challenge for companies. Flexible manufacturing system employed automated guided vehicles (AGV) to maintain efficiency and flexibility. This paper presents a new non-linear mathematical programming model to group n machines into N loops, to make an efficient configuration for AGV system in Tandem layout. The model minimizes both inter-loop, intra-loop flow and use balanced-loops strategy to balance workload in system simultaneously. This paper significantly considers multiple-load AGVs, which has capability of reducing fleet size and waiting time of works. A modified variable neighborhood search method is applied for large size problems, which has good accuracy for small and medium size problems. The results indicate that using multiple load AGV instead of single load AGV will reduce system penalty cost up to 44%. پرونده مقاله -
دسترسی آزاد مقاله
5 - Gentle Survey on MIR Industrial Service Robots: Review & Design
Ata Jahangir Moshayedi Ge Xu Liefa Liao Amin KolahdoozService robots are one of the most critical robot's applications that enter human life. This domain consists of elements from human health to industry. Somehow, this robot type can save a human's life or help him secure from the load-carrying job and all repeated work t چکیده کاملService robots are one of the most critical robot's applications that enter human life. This domain consists of elements from human health to industry. Somehow, this robot type can save a human's life or help him secure from the load-carrying job and all repeated work that may interfere with job accuracy. Based on ISO 8373:2012 The service robots Split into personal service types of robots characteristically meant to use outside of manufacturing and the professional setting robots and professional service robots that can use as non-commercial individuals professional service robots can use as commercial professionals. Even as the service robot development research has shown various new service robots with specific ability proposed, some parts in these robot types are similar and are day by day extended. MIR and AGV robots are the most famous service robot with dual ability in the industry and the home applicant. This paper covers most of the papers published on the MIR platform to address the detailed design and part of these types, which can be useful for industries and researchers. The most significant thing that has been done through this review is a service robot design. On the other hand, the researcher has more investigation on the service robot application and has study the MIR Industrial/service robot platform. پرونده مقاله -
دسترسی آزاد مقاله
6 - Investigation of a Fully-automated Manufacturing Environment Realized through a Flexible Logistic System
Jan-Hinrich Kämper Arne StaschModern industrial production and transportation systems require agile material handling systems. Changing requirements demand flexibility in transportation layout and control systems that are adaptable to the actual needs. Decentralized control systems promise complexit چکیده کاملModern industrial production and transportation systems require agile material handling systems. Changing requirements demand flexibility in transportation layout and control systems that are adaptable to the actual needs. Decentralized control systems promise complexity reduction and dependability while centralized approaches improve planning and allow general optimization. By using the use case of a cross-docking logistic system the paper describes how this approach can be combined and implemented by using an agent-based control system on a decentralized lightweight microcontroller infrastructure. The scenario applies to manufacturing environments with modularized assembly lines. These modules are connected by different transport units which merge into an intelligent infrastructure including AGVs, conveyors, and storage. پرونده مقاله -
دسترسی آزاد مقاله
7 - A new memetic algorithm for mitigating tandem automated guided vehicle system partitioning problem
Parinaz PourrahimianAutomated Guided Vehicle System (AGVS) provides the flexibility and automation demanded by Flexible Manufacturing System (FMS). However, with the growing concern on responsible management of resource use, it is crucial to manage these vehicles in an efficient way in ord چکیده کاملAutomated Guided Vehicle System (AGVS) provides the flexibility and automation demanded by Flexible Manufacturing System (FMS). However, with the growing concern on responsible management of resource use, it is crucial to manage these vehicles in an efficient way in order reduces travel time and controls conflicts and congestions. This paper presents the development process of a new Memetic Algorithm (MA) for optimizing partitioning problem of tandem AGVS. MAs employ a Genetic Algorithm (GA), as a global search, and apply a local search to bring the solutions to a local optimum point. A new Tabu Search (TS) has been developed and combined with a GA to refine the newly generated individuals by GA. The aim of the proposed algorithm is to minimize the maximum workload of the system. After all, the performance of the proposed algorithm is evaluated using Matlab. This study also compared the objective function of the proposed MA with GA. The results showed that the TS, as a local search, significantly improves the objective function of the GA for different system sizes with large and small numbers of zone by 1.26 in average. پرونده مقاله -
دسترسی آزاد مقاله
8 - Two optimal algorithms for finding bi-directional shortest path design problem in a block layout
M Hamzeei R Zanjirani FarahaniIn this paper, Shortest Path Design Problem (SPDP) in which the path is incident to all cells is considered. The bi-directional path is one of the known types of configuration of networks for Automated Guided Vehi-cles (AGV).To solve this problem, two algorithms are dev چکیده کاملIn this paper, Shortest Path Design Problem (SPDP) in which the path is incident to all cells is considered. The bi-directional path is one of the known types of configuration of networks for Automated Guided Vehi-cles (AGV).To solve this problem, two algorithms are developed. For each algorithm an Integer Linear Pro-gramming (ILP) is determined. The objective functions of both algorithms are to find the shortest path. The path must be connected and incident to all cells at least in one edge or node. A simple Branch-and-Cut ap-proach is used to solve the ILP models. Computational results show that the models easily can solve the prob-lem with less than 45 cells using a commercial ILP solver. پرونده مقاله -
دسترسی آزاد مقاله
9 - Solving the tandem AGV network design problem using tabu search: Cases of maximum workload and workload balance with fixed and non-fixed number of loops
E Miandoabchi R Zanjirani FarahaniA tandem AGV configuration connects all cells of a manufacturing area by means of non-overlapping, sin-gle-vehicle closed loops. Each loop has at least one additional P/D station, provided as an interface between adjacent loops. This study describes the development of t چکیده کاملA tandem AGV configuration connects all cells of a manufacturing area by means of non-overlapping, sin-gle-vehicle closed loops. Each loop has at least one additional P/D station, provided as an interface between adjacent loops. This study describes the development of three tabu search algorithms for the design of tandem AGV systems. The first algorithm was developed based on the basic definition of a tandem network. The sec-ond and third algorithms, consider no preset number of loops and try to evenly distribute workload among loops by using workload balance as their objective functions. They generate different design scenarios for the tandem network, which can be evaluated and selected using a multi-attribute objective function. The first al-gorithm and the partitioning algorithm presented by Bozer and Srinivasan are compared for randomly gener-ated problems. Results show that for large-scale problems, the partitioning algorithm often leads to infeasible configurations with crossed loops in spite of its shorter running time. However, the newly developed algo-rithm avoids infeasible configurations and often yields better objective function values. پرونده مقاله -
دسترسی آزاد مقاله
10 - Optimizing AGV Colonie’s Efficiency by Fuzzy Simulation
Shabnam Ezadpanah Alireza Mohammadion Armen AdamianThis is an adoptive design of ant colony system and has been generalised to AGV transport system, predetermined targets replacement results has been evaluated simulating four AGV in Mat lab by Particle Algorithm and fuzzification and simulating the operative environment چکیده کاملThis is an adoptive design of ant colony system and has been generalised to AGV transport system, predetermined targets replacement results has been evaluated simulating four AGV in Mat lab by Particle Algorithm and fuzzification and simulating the operative environment with regard to constant velocity and different results has been compared to each other by changing robots’ location and replacement of obstacles in the environment and using laser guidance system. Optimising considered sensor’s arrays led to more efficient and faster feedback. Regarding improvements mentioned, AGVs passing the obstacles with ease, choosing the shortest distance to the target and are flexible enough in case of one of the AGVs failure. 1- The AGV that has worked less than the others (from distance perspective), 2- the AGV which has been the closest to the failed AGV and 3- the AGV that has replaced fewer load. in fact, the system was able to operate more efficiently than when using an AGV. پرونده مقاله -
دسترسی آزاد مقاله
11 - PID Tuning Method on AGV (automated guided vehicle) Industrial Robot
Ata Jahangir Moshayedi Atanu Roy Liefa LiaoControlling a system can be done in various ways and methods. The classical method which even now a day as a solution works is PID which in that with some method three-parameter of controller called P (Proportional), I (Integral), D (Derivational) tuned to have the best چکیده کاملControlling a system can be done in various ways and methods. The classical method which even now a day as a solution works is PID which in that with some method three-parameter of controller called P (Proportional), I (Integral), D (Derivational) tuned to have the best controlling response from a system. The AGV robot as the abbreviation of the Automated Guided Vehicle is as a famous robot platform which used in various industries relies on PID controllers in various ways. Each AGV or Machine has its own set of function, hence, in order to accomplish the exact set of workload more efficiently one need to actually tune the PID parameters accordingly so that there cannot be an intolerable amount of energy loss, inefficiency rate, lag, lack of robustness etc. In this paper over than introduction of PID controller and see the effect of each parameter on the real system the compassion between hired methods on AGV robot are investigated. As this review indicates that various PID tune method are used based on system requirements with the help of Lyapunov Direct Method, traditional Ziegler Nichols, Fuzzy controller, human immune system called the humoral, neural network, etc to control the speed and steering of an AGV systems. پرونده مقاله -
دسترسی آزاد مقاله
12 - AGV (automated guided vehicle) robot: Mission and obstacles in design and performance
Ata Jahangir Moshayedi Li Jinsong Liefa LiaoThe AGV (automated guided vehicle) was introduced in UK in 1953 for transporting. But nowadays, due to their high efficiency, flexibility, reliability, safety and system scalability, they are used in various application in industries. In brief, the AGV robot is a system چکیده کاملThe AGV (automated guided vehicle) was introduced in UK in 1953 for transporting. But nowadays, due to their high efficiency, flexibility, reliability, safety and system scalability, they are used in various application in industries. In brief, the AGV robot is a system which typically made up of vehicle chassis, embedded controller, motors, drivers, navigation and collision avoidance sensors, communication device and battery, some of which have load transfer device. In this review paper, based on existing systems, the AGV structures are studied and compared from various point of view and analysis of the AGV structure is done for design. The AGV (automated guided vehicle) was introduced in UK in 1953 for transporting. But nowadays, due to their high efficiency, flexibility, reliability, safety and system scalability, they are used in various application in industries. In brief, the AGV robot is a system which typically made up of vehicle chassis, embedded controller, motors, drivers, navigation and collision avoidance sensors, communication device and battery, some of which have load transfer device. In this review paper, based on existing systems, the AGV structures are studied and compared from various point of view and analysis of the AGV structure is done for designer. پرونده مقاله
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