Showing papers in "International Journal of Intelligent Systems and Applications in 2010"

Artificial Fish School Algorithm Applied in a Combinatorial Optimization Problem

Abstract: An improved artificial fish swarm algorithm (AFSA) for solving a combinatorial optimization problem— a berth allocation problem (BAP), which was formulated. Its objective is to minimize the turnaround time of vessels at container terminals so as to improve operation efficiency customer satisfaction. An adaptive artificial fish swarm algorithm was proposed to solve it. Firstly, the basic principle and the algorithm design of the AFSA were introduced. Then, for a test case, computational experiments explored the effect of algorithm parameters on the convergence of the algorithm. Experimental results verified the validity and feasibility of the proposed algorithm with rational parameters, and show that the algorithm has better convergence performance than genetic algorithm (GA) and ant colony optimization (ACO).

Operational Mechanism and Evaluation System for Emergency Logistics Risks

Abstract: Lots of risks existed in the operating process of emergency logistics especially when natural disasters happened. Both operating mechanism and evaluation system research on Emergency Logistics Risks (ELR) are the basis of effective recognizing, preventing and responding to risks, so it’s of great theoretical and practical significance to study the formation and influence mechanism and to establish an evaluating index system for ELR. Firstly, some foundation research about ELR was carried out, including definition, characteristics and classification of ELR. The formation and influence mechanism of ELR were discussed. The research of questionnaire survey offered an objective support for theoretical mechanism and index system establishment. Then, the evaluating index system for ELR was established. This system was a multi-level index system, and mainly evaluated by the decision-making risk, dispatching and commanding risk, organizing and coordinating risk, executing and controlling risk, resources supporting risk and their sub index. The establishment principles and significance of the index system were discussed. Then, the fuzzy comprehensive evaluation and Delphi method were used to confirm the index weight and value. Finally, a case analysis on ELR of Yushu earthquake was conducted to demonstrate the evaluating index system and to evaluate the actual risk level.

Design and Simulation of Storage Location Optimization Module in AS/RS Based on FLEXSIM

Abstract: This paper firstly points out the importance of the storage location optimization in Automated Storage and Retrieval Systems (AS/RS). Then it has analyzed the basic situation of the current storage location assignment strategy, and indicated the deficiency of the storage location selection under the current strategy. Afterwards, it has designed the storage location optimization module in AS/RS. And then it has constructed the mathematical model on the storage location assignment in AS/RS, and then optimized and solved it, performed instance simulation design and analysis on the storage location assignment by means of Flexsim. Finally, it has concluded that the storage location assignment model after optimization would solve the storage location assignment problem in AS/RS effectively and improve the loading-unloading efficiency, as will provide technical support for the enterprise to improve efficiency and reduce cost.

Research on the Layout of National Economic Mobilization Logistics Centers

Abstract: The problem of the layout of NEMLC (National Economic Mobilization Logistics Center) is one of the most important long-term decision-making issues. The result of NEMLC's layout directly impacts many aspects of mobilization, such as time, reliability, quality, efficiency, cost, and so on, consequently affects the effect of the mobilization. Reasonable NEMLC layout can bring people convenience in the daily life, reduce costs, and improve service efficiency and competitiveness. Poor NEMLC layout often brings a great deal of inconvenience and loss, and even leads to mobilization failure. Under the restriction of mobilization time, the paper establishes the layout model that one or more mobilization logistics centers provide the material to the mobilization demanding place. The mobilization goods or service can reach the demanding place to carry into mobilization execution within the given time, and the number of the built NEMLCs is the least.

Multi-agent-based Fuzzy Dispatching for Trucks at Container Terminal

Abstract: At container terminals, containers are transported from the marshalling yard to the quay and vice versa by Container Trucks (CTs). This study discusses how to dispatch CTs by utilizing information about pickup and delivery locations and time in future delivery tasks based on dynamic dispatching strategy in which multiple tasks are matched with multiple CTs. n this paper, Multi-agent system (MAS) is used as the basis for an intelligent dispatch system. To aim at that the characteristic of management of container terminal is how to optimize resource of terminal, the trends of decision-making way for management of container terminal, research and application of Multi-Agent system is summarized. Relationship between transport tasks and service of CTS has been taken as a contract net using the fuzzy set theory and method. Considering the load of communication and consultation efficiency in system, the bidirectional negotiation mechanism is adopted. The dispatching model based on Contract Network Protocol (CNP) using bidirectional negotiation is provided for assigning optimal delivery tasks to CTs and fuzzy reasoning process of dispatching decisions is suggested. The method has both virtues of precision of static planning and flexibility of CNP and has been confirmed by cases.

A Novel DTC-SVM Method For Induction Motor Fed By Matrix Converter

Abstract: This paper presents a novel DTC-SVM method for matrix converter (MC) fed induction motor. The advantages of DTC method are combined with the advantages of the matrix converter based on space vector modulation (SVM) technique. This proposed novel method provides a precious input power factor control capability beside the high control performances. Furthermore, Conventional principles of DTC and SVM of MC were described. The combination of the two was given in detail. The FFT spectrum analysis of the input current shows the better harmonic contents as compared to the conventional DTC method. Finally, the simulation and experiment research were carried out to identify the new method effectiveness. The results of induction motor control at both steady state and transient state are shown to improve the low-speed performance and strong adaptability of this novel control strategy.

Designing and Decision Making of Transport Chains between China and Germany

Abstract: Optimization of an international transport chain may contribute significantly to a successful outcome in international trade. The performance of various modes of transport influences the selection of one over others. This paper analyses the transport chain between China and Germany, comparing routes and aiming to identify the best practices and chose the optimal transport mode. Through analysing secondary data, the different means of transport are presented. The SWOT analysis was selected to analyse and compare the competitive operation of the various methods of transport between China and Germany. This helps us understand what determines the selection of one mode of transport mode rather than another; the development of rail transport between China and Germany should be urged, in addition to the air and sea modes; Price, timing, level of service and relationship with forwarder are vital factors in determining the route option between China and Germany. More secondary data should be used to validate the research in the future. (Abstract)

Momentum Based Level Set Method For Accurate Object Tracking

Abstract: This paper proposes a novel object tracking method that is robust to a cluttered background and large motion. First, a posterior probability measure (PPM) is adopted to locate the object region. Then the momentum based level set is used to evolve the object contour in order to improve the tracking precision. To achieve rough object localization, the initial target position is predicted and evaluated by the Kalman filter and the PPM, respectively. In the contour evolution stage, the active contour is evolved on the basis of an object feature image. This method can acquire more accurate target template as well as target center. The comparison between our method and the kernel- based method demonstrates that our method can effectively cope with the deformation of object contour and the influence of the complex background when similar colors exist nearby. Experimental results show that our method has higher tracking precision.

Measuring and Evaluation on Priority Lanes

Abstract: Along with economic development, cities are increasingly congested in China. In order to eliminate peak-hour congestion, many cities establish priority lanes, commonly bus lanes. Although priority lanes could help Local Authorities gain its short-term management objectives, at the same time, it would greatly infringe on the legitimate rights of other vehicles and waste the scarce road resources, which is rigorously proved by mathematical models in this paper. In the long run, priority lanes would make social conflicts more intensified, and therefore highly undesirable. On the contrary, the social system engineering, combined with High Occupancy Vehicle (HOV) lanes and High Occupancy Toll (HOT) lanes, is the right way to alleviate overcrowding and build a Low-Carbon harmonious society.

Research on Association with Freight Transit Period and Forwarding Time base on Logistics conditions

Abstract: The whole process of freight forwarding includes multiple links. The consumption time of every link and its operational efficiency may affect the entire freight forwarding time, which can influence the transit period of freight, as well as the formulation and achievement of the transportation organizations scheme and the transportation contract. In order to analyze the existed problems in present calculation method of railway transit period, and the effects of logistics on forwarding time, on the basis of investigating and literature, Railway freight forwarding process and factor of logistics on railway freight forwarding time were analyzed, and average speed of through train, ordinary through train and high- speed train, and daily average running tariff kilometer and time were analyzed, and statistical results were exa ined by adopting 2 χ testing method, finally, daily average running tariff kilometer and time of logistics developed and under- developed area were comparative analyzed, from which daily average running tariff kilometer and time were obtained. The analytical results show that the average speed, daily average running tariff kilometer and time respectively obeys normal distribution, the maximum difference value between the transit period calculated by present method and the practical forwarding time of freight is four 4.5 days, which show that the method can not objectively responds the freight forwarding time of each kind of freight transport product under logistics condition. m

Time Synchronization under 1PPS Signal in Distributed Real-time Simulation System

Abstract: Time synchronization is one of the key points in distributed of a real-time simulation system. At first, a distributed simulation system is introduced. Secondly, time synchronization method under 1PPS signal is put forth. Thirdly, the relevant technology of time synchronization are studied, including system structure, SNTP, 1PPS signal and control logic. Vxworks watch dog timer mode and timecard counter mode under this method are also analyzed in detail and the precision is presented. Fourthly, Arena software is chosen to model and simulate the time synchronization procedure. At last, the whole simulation model is constructed and the experiment results are given out to prove the efficiency of the synchronization method.

The Obstacle Detection and Measurement Based on Machine Vision

Abstract: To develop a quick obstacle detection and measurement algorithm for the image-based autonomous vehicle (AV) or computer assisted driving system, this paper utilize the previous work of object detection to get the position of an obstacle and refocus windows on the selected target. Further calculation based on single camera will give the detailed measurement of the object, like the height, the distance to the vehicle, and possibly the width. It adopts a two camera system with different pitch angles, which can perform real-time monitoring for the front area of the vehicle with different coverage. This paper assumes that the vehicle will move at an even speed on a flat road, cameras will sample images at a given rate and the images will be analyzed simultaneously. Focus will be on the virtual window area of the image which is proved to be related to the distance to the object and speed of the vehicle. Counting of the blackened virtual sub-area can quickly find the existence of an obstacle and the obstacle area will be cut to get the interested parameter measurements for the object evaluation.

A Partial Backlogging Inventory Model with Time-Varying Demand During Shortage Period

Abstract: Harris's classic square root economic order quantity (EOQ) model forms the basis for many other models that relax one or more of its assumptions. A key assumption of the basic EOQ model is that stockouts are not permitted. Due to the excess demands, stock-out situations may arise occasionally. Sometimes, shortages are permitted and they are backordered and satisfied in the very next replenishment. Therefore the objective of this paper is to develop a partial backlogging inventory model, and proposes a new algorithm to minimize the total cost, at the same time also propose the prediction method and algorithm of ordering period. Finally, a practical example of the numerical analysis is given.

Study on Optimization of Phase Offset at Adjacent Intersections

Abstract: Optimization of the phase offset at adjacent intersections is the key parameter regarding coordinated control of traffic signal for adjacent intersections, which decides the effect of the coordinated control for adjacent intersections. According to characters of saturated traffic flow of Chinese urban road, this thesis establishes a model for optimization of phase offset for adjacent interactions and finds a solution from such model by adopting genetic algorithm. The model is verified by actual traffic flow datum of two adjacent signal intersections on Changan Avenue. Then a comparison is made between the optimization result of such model and that of the existing mathematical method and SYNCHRO model, which indicates that the model established by this thesis can reduce the delay suffered by vehicles at the intersections and increase the traffic efficiency of the intersections

Force-Directed Method in Mirror Frames for Graph Drawing

Abstract: The most widely used algorithms for graph drawing are force-directed algorithms. We should modify a hybrid force model that is coupling a traditional spring force model and a novel repulsive force model will be proposed to solve the graph drawing problems in 2-D space. Especially, regular triangle drawing frame can be applied to binary tree drawing problems that on an important contribution to computer science. And apply circle drawing frame to normal graph drawing problems, we get satisfactory and aesthetic criteria graphics.

Application Research on High Resolution Radar Target Aggregation

Abstract: In high resolution radar system, the same target always has original data; so we need to merge multiple data from the same target as one target. Because of the system’s real-time requirement, we usually have to carry out target aggregation as quickly as possible. In this paper, we propose a quick target aggregation method based on clustering algorithm. The proposed method divides original data into subsets by single dimensional distance, and then merges subsets according to single dimensional distance and setdensity. At last we apply the proposed method to carry out target aggregation for airport scene surveillance radar system. Experimental result shows the proposed method has high execution efficiency and is not sensitive to noise data; it is useful for high resolution radar target aggregation.