The theory of constraints (TOC) has become a valuable system in modern operations management. Using the ideas and methods of the TOC, companies can achieve a large reduction of work-in-process and finished-goods inventories, significant improvement in scheduling performance, and substantial earnings increase. The purpose of this paper is to calculate the optimal size of the time buffer which is used to accommodate disruptions in production processes and provide maximum productivity of capacity constrained resources. After the problem formulation in terms of single server queueing model, we observed the system behavior by sensitivity analyses.

This paper describes a real-time manufacturing scheduling system on Internet using DBR(Drum-Buffer-Rope) scheduling method. We intend to change company-oriented manufacturing scheduling, which has been used at most manufacturing companies, to customer-oriented manufacturing scheduling. Customers can not only choose product kinds, quantities and order due dates, but also evaluate optimum order due date by themselves in real-time through internet and then the results will be converted into practical manufacturing scheduling. If the company cannot meet the customer order due date, it will offer reliable and accurate information to the customers by suggesting the earliest order due date. To evaluate the customer order due date in real time, companies should be able to estimate their accurate production capacity. This research uses Goldratt's DBR scheduling method to realize that function. The DBR scheduling does not recognize the production capacity of the whole company, but only of the constraint resources which have a great effect on the company throughput. Thus, it can improve the customer service level as well as the profit by performing more dynamic and reliable scheduling through Internet.

This paper suggests a detailed design of APS(Advanced Planning & Scheduling) system using the DBR (Drum-Buffer-Rope) which is a finite capacity scheduling logic of TOC(Theory of Constraints). Our design is composed of four modules; Network, Buffer, Drum and Subordination. The Network module defines the Product Network which is built from BOM and routings. The Buffer module inserts the Buffers into the Product Network. The Drum module describes detail procedures to create Drum Schedule on the CCR(Capacity Constraint Resource). The Subordination module synchronizes all non-constraints to the constraints by determining the length of Rope. This design documented by ARIS.

Production Improvement Method in TOC consists of five steps, but it is very difficult for most firms to implement it because it lacks the detailed methods at each step. This paper suggests some of detailed methods to implement the TOC. In the first step, computer simulation is used to identify the constraints in production lines. Subsequently, ASP, AUT, and CM calculation are defined for the second step, which are helpful to exploit the company's constraints. We also suggest the OEE method to effectively exploit the constraints of production lines in the factory. Finally the TOC/OEE procedure is suggested to optimize the investment in the fourth step. As an illustrative example, we introduce a case of a wafer manufacturer to adopt the suggested methods. The benefits of implementating the suggested methods are addressed in the framework of the balanced scorecard.

It is discussed how to determine time windows for pickups and deliveries, which have been assumed to be given in all most of previous studies on traveling salesman problems with time window, vehicle routing problems with time window, vehicle scheduling and dispatching problems, and so on. First, time windows are classified into four models (DR, DA, AR, and AA) by customers‘ polices. For each model, it is shown how a time window is related to various cost terms of suppliers and customers. Under the assumption of collaborative supplier-customer relationship, an integrated cost model for both supplier and customer is constructed for determining boundaries of time windows. The cost models in this paper consists of cost terms that depend on waiting time, early arrival time, late arrival time, and rejection of receipt. A numerical example is provided and results of the sensitivity analysis for some parameters are also provided to help intuitive understanding about the characteristics of the suggested models.

The objective of this paper is to design the dynamic route guidance system(DRGS) and develop a genetic algorithm(GA) for finding the multiple shortest paths in real traffic network. The proposed GA finds a collection of paths between source and destination considering turn-restrictions, U-turn, and P-turn that are genetically evolved until an acceptable solution is reached. This paper also shows the procedure to find the multiple shortest paths in traffic network of Seoul.

In this paper, a scheme of scheduling a bottleneck operation is presented for production planning of make-to-order. We focus on the problem of capacity-dependent processing time in which processing time of the bottleneck operation is not fixed, but varies with job sequence or equipment capacity. For this, a genetic algorithm is applied for job sequencing with an objective function of mean square of weighted deviation. An experimental study is implemented in power transformer plant and results are compared with those of the EDD rule. It shows that the genetic algorithm is relatively good for most cases.

In this study, we deal a spatial scheduling system for the block painting process in the shipbuilding industry. In general, the spatial scheduling for the block painting process is a very complicated task. Because spatial allocation of each block in blasting and painting cells is considered simultaneously. Thus the spatial scheduling for the block painting process is the problem of planning and control of operation, which arises in shipyard. This system is developed for blocks to meet the delivery date given by the shipyard production planning system, to maximize space utilization of blasting and painting cells and to balance workload among working teams. And it has been tested using actual scheduling data from a shipyard and successfully applied in a paint shop in a shipbuilding company.

SNMP (Simple Network Management Protocol) is applied to develop a web based monitoring system for manufacturing processes. SNMP agents in manufacturing facilities collects monitoring data from machine controllers and send them to a web-server to be stored in a database by an SNMP managing agent. Clients can access these data using any web-browser. This study developed these agents and MIB (Management Information Base), a protocol to represent the status of machines, that can be used appropriately to monitor manufacturing processes.

In this paper, We study the development of Quality Competitiveness Assessment System(QCAS), which is a computer software developed to support the assessment criteria. It, first, describes the structure of the assessment criteria and the quality competitiveness model developed for promoting quality management. QCAS is then further explained by delineating its design, functional characteristics, and feedback from the experts. A systematic procedure is also proposed for possible application of QCAS in real world situations. Finally, This research propose a systematic procedure that can be used to apply QCAS in setting up a long-term plan for continuous quality improvement.

The economic effects of informatization are differently occurred according to industry types. Thus an evaluation methodology which reflects the industry type characteristics of informatization is needed. In this paper, we develop and analyze the indices for evaluating economic effects through informatization according to industry types, such as manufacturing, construction, financial services and marketing services. The factors related to performance of enterprise informatization can be defined as cost factors, effect factors, risk factors and influence factors. Effect factors are defined as quantitative or qualitative performance of informatization and classified into operational effect factors and strategic effect factors. The influence factor is defined as characteristics of informatization for industry types, that is, value chain of business and business products or services. Economic effect indices are classified according to the activity of business value chain. Economic effects indices of this research can be expected to play a role of general and standardized factors for economic evaluation of industry informatization.

Brain Korea(BK) 21 is a plan launched in 2000 to strengthen the competitiveness of research and education quality of universities in Korea. In this paper, we evaluate BK21 plan using both ACSI and SEM in terms of the satisfaction level of graduate students in various dimension. The results of our study indicate that in general BK21 has a significant impact on the satisfaction of the graduate students involved in BK21. It turns out that the scholarship is the only one component which is positively related to the students' satisfaction while the industry-university cooperation system and the international conference attendance and Journal publication have negative relationship with satisfaction. In addition, it appears that those who graduated from other college and participate in BK21 tend to be more satisfied than those who admitted to the graduate program from the same college. Our study results imply that some strategies for BK21 need to be modified and effectively implemented in order to increase the number of applicant of good quality and level up the satisfaction level of the graduate students in Korea.