Ruey-Shun Chen

A hybrid genetic algorithm approach on multi-objective of assembly planning problem

Abstract In practice, modeling an assembly system often requires assigning a set of operations to a set of workstations. The aim is to optimize some performance indices of an assembly line. This assignation is usually a tedious design procedure so a significant amount of manpower is required to obtain a good work plan. Poor assembly planning may significantly increase the cost of products and reduce productivity. However, these optimization problems fall into the class of NP-hard problems. Finding an optimal solution in an acceptable time is difficult, even using a powerful computer. This study presents a hybrid genetic algorithm approach to the problems of assembly planning with various objectives, including minimizing cycle time, maximizing workload smoothness, minimizing the frequency of tool change, minimizing the number of tools and machines used, and minimizing the complexity of assembly sequences. A self-tuning method was developed to correct infeasible chromosomes. Several examples were employed to illustrate the proposed approach. Experimental results indicated that the proposed method can efficiently yield many alternative assembly plans to support the design and operation of a flexible assembly system.

A case study in the design of BTO/CTO shop floor control system

Although computerized information systems are conventionally used to control production, applying a manual approach and improper logistical assignments typically reduces operating efficiency and increases customer service response time. Satisfying the requirements of remaining competitiveness in the current marketplace, such as offering build-to-order (BTO) or configuration-to-order (CTO) services is difficult. This study presents an integrated information system for use in shop floor controlling systems (SFCS) for kitting parts, producing goods, packing finished goods and distributing them, to enhance the performance of the BTO/CTO production system. Several information technologies and devices, such as barcode system, the electronic pick-to-light picking system, electronic Kanban (eKanban), and others are adopted to support the relevant logistics. A personal computer (PC) manufacturer is used to demonstrate the proposed system. The findings of the study reveal that the proposed information system can respond to the status of the production line in real time. This responsiveness can help the production controller to make a suitable decision and quickly meet the requirements of the BTO/CTO production system.

Optimizing assembly planning through a three-stage integrated approach

Abstract This study proposes a three-stage integrated approach with heuristic working rules to assist the planner to develop a better assembly plan. In the first stage, Above Graph and transforming rules were used to create a correct Explosion Graph of the assembly models. In the second stage, a three-level relational model was developed to create a complete relational model graph and an incidence matrix. In the third stage, a mathematical model, based on a penalty index was formulated, and a revised minimum spanning table method was used to generate and evaluate a feasible assembly sequence. The example of a military system is presented to demonstrate the feasibility of the proposed method. The contribution of this study is based on a design for assembly potential applications of three-dimensional (3D) component models to assist manual or automatic assembly in a virtual environment, and allows the designer to recognize the relative position, constraints and relationships of 3D components using graph-oriented methods: Above Graph, assembly precedent diagram, and relational model graph.

Metadata management system: design and implementation

Commonly, an organizational information system may have various data types and directory formats. It usually employs different metadata formats to represent the documents. Although the metadata system can cover the different formats of documents, there still exist the integration problems in various metadata systems. This may lower the performance of data processing and impede information sharing. Research focuses on the model of using multi‐XML schema to construct an XML system framework. Through a complete hierarchical tree structure definition of inner elements, the proposed model can settle the weakness of traditional object‐oriented languages in information sharing; it can also eliminate the constraints of storage and management among heterogeneous metadata while processing different metadata information.

Web Services: XML‐based system integrated techniques

The integration of information systems must consider various aspects, including the individuals of an organization, cooperating with other vendors, and the connections within this organization. The advantages of integration include shortening the negotiation process among the organization and the cooperating vendors, saving time for the users, and identifying the interface management. However, the greatest difficulties are how to integrate different system platforms and implement technical aspects into a suitable Web‐interface for users to operate. Information technology companies have developed Web Services which rely on the flexibility of the Extended Mark‐up Language. The services not only apply to integrated information systems, but also provide open services in Web environments. This article evaluates the feasibility of Web Services for application in integrated library information systems.

A web-based ERP data mining system for decision making

Most of the enterprises having finished, one after the other, in the automation of transaction processing, the key issue for the future competitiveness of enterprises will be the automation of decision-making processing and forecast processing. To complement the deficiency of the forecast flow in enterprise resource planning (ERP) systems, we propose here a data searching architecture that can be built on the ERP system while meeting the individual needs of enterprises and providing real time accurate forecasts on changes in the future market. The present paper is based on the transaction flow processing power of ERP. It integrates the database and online analytical processing (OLAP) technologies, transaction and decision making flows of ERP, then uses data searching technology to integrate decision making and forecast flows. The data-searching engine is the actual design of a categorising module. This research can finish within an hour the analyses and forecasts, which would take the traditional information technology system about three weeks to process the mock analyses. This makes decision making easier for entrepreneurs and thus enables them to handle well the always-changing market and establish themselves firmly. This research applies the ERP data searching system on the IC testing industry. Using the ERP data searching system in this study to investigate the testing status of the testing machine, resolutions are found pinpointing the factors that cause the high frequency of machine down. The results of, according to the actual experiment, the tested testing machine shows an average improvement rate of 83% over the number of machines down.

Developing an XML framework for an electronic document delivery system

The Internet has forced libraries to consider how to assist users to rapidly retrieve information. Such a consideration has accelerated the development of electronic publishing and has positioned the library as mediator between users and providers: archiving information circulation and providing secure copyright clearance through an efficient electronic document delivery and payment mechanism. This work develops an Extensible Markup Language (XML) framework for electronic document delivery that offers a novel electronic document delivery system and also locates publishers who can provide the copyrighted material in an electronic format via the OPAC. The proposed electronic document delivery system has four functions: (1) it enables the electronic document payment; (2) it shortens the time between inquiry and electronic document retrieval; (3) it anticipates the changing role of libraries; and (4) it reduces the printed collection load of libraries.

Intelligent warehousing management systems using multi-agent

This paper presents an agent-driven with automatic data capturing approach to support warehousing management that involves issuing shipping schedules, allocating the storage spaces, and arranging the order-picking routes. Some heuristic working rules based on class-based allocation principles in accordance with the bill of materials (BOM) are applied to guide multi-agent processing the warehousing transactions. A two-dimensional (2D) barcode systems, PDF417, is set up to identify the storage spaces and the stocks such that the picker can use a notebook with barcode reader to diagram the picking routes and automatic capture the data of picking parts. That makes the picking tasks much easier as it does not rely on the dedicated picker. A WEB-based information system is constructed to exchange the related messages. The purchasing orders and shipping lists are formed as XML/EDI formats and interchanged through the internet; and internal data are transacted via intranet under a client server system. By using the presented approaches, data transaction will be more accurate and real-timed. Moreover, warehouse spaces are used flexibly and efficiently, logistics costs are reduced, and services for customers are responded to quickly.

Application of the multi-agent approach in just-in-time production control system

Although the computerised information system is conventionally used in production control, applying a manual-driven approach and improper logistics assignments typically lead to lower operating efficiency and a slower customer service response time. This study presents an experimental multi-agent system mobile enterprise information portal (MEIP), developed for real-time production controlling across the intra-/inter-organisational supply system. A new formalism called tri-base model of the multi-agent communication/negotiation mechanism is employed to simulate the just-in-time (JIT) control manufacturing system. Several novel technical devices such as mobile agent system, two-dimensional (2D) barcode system, etc., are used to establish the real-time data capture and communication system. The findings of the case study indicate that the experimental multi-agent system can respond to the status of the production line in real time. This can help the production controller making an effect decision.

Optimisation of assembly plan through a three-stage integrated approach

Assembly planning is commonly a tedious design procedure requiring a significant amount of manpower to obtain a feasible work plan. Poor assembly planning not only results in higher product cost and lower productivity but may also negatively impact the reliability, maintainability, and availability of a product during its life cycle. This study proposes a three-stage integrated approach with some heuristic working rules to assist the planner to develop a feasible assembly plan. In the first stage, Above Graph and transforming rules are used to create a correct Explosion Graph of the assembly models. In the second stage, a three-level relational model is developed to create a complete relational model graph and an incidence matrix. In the third stage, a genetic algorithm approach is used to generate and evaluate a near-optimal assembly sequence. An example of a military system is presented to demonstrate the feasibility of the proposed method.