In this paper, we consider wavelength assignment problem (WAP) in Wavelength division multiplexed (WDM) unidirectional optical telecommunication ring networks. We show that, even though WAP on unidirectional ring belongs to NP-hard, WAP can be exactly solvable in real-sized WDM rings for near future demand. To accomplish this, we convert WAP to the vertex coloring problem of the related graph and choose a special integer programming formulation for the vertex coloring problem. We use a column generation technique in a branch-and-price framework for the suggested formulation. We also propose some generic heuristics and do the performance comparison with the suggested optimization algorithm.

Manufacturing companies are implementing a so-called customer-centered supply chain management to have a competitive advantage. In these efforts, collaboration not only within a company but also with suppliers, partners and customers is emphasized. The fast delivery, reducing the total lead-time from development to delivery, is pursued more than ever, though the quality and cost are still importantly regarded. Die manufacturing companies are not exception from these trends, because a die is a necessary tool for almost manufacturing industries. The planning and scheduling system plays an important role in supply chain management. In this study, we address a scheduling problem of a die manufacturing company. The problem is very complex due to many reasons including the uncertainty in environment and the complexity of constraints. Considering the importance of due-date satisfaction and human planners' roles, we designed the solution algorithm and the user interface respectively. In the implementation phase, modeling constructs and basic solution algorithms of ILOG solver and ILOG scheduler are used. In the paper, the problem and the algorithm are described with ILOG constructs, and the experience of use is also addressed.

In this research we have developed a prototype which manages a product structure and configuration of a product under distributed heterogeneous computing environments. First, the data schema for product structure and configuration which can represent options and effectivity is proposed. Second, a technique to use JAVA and CORBA is suggested for the exchange of product structure among multiple servers in CITIS environments. Functions of the prototype related to option-based product structure are described to help readers' understanding.

In this paper, we analyze the inventory and inspect cost of small-to-medium-sized enterprises which are getting orders from large enterprises using JIT(just in time) system. So far, we have not found the good inventory and inspect cost formula for the small-to-medium-sized enterprises. In this paper, we first survey the inventory and inspect strategy and cost formula of the small-to-medium-sized enterprises in this country. We are trying to mathematical modelling of several cases depending on the inventory and inspect strategy of large enterprises. We suggest inventory and inspect several cost formula by using the method minimizing the total cost of the small-to-medium-sized enterprises. We also give some numerical examples for your understanding.

In this paper, an efficient algorithm is proposed to find parting lines(PL) and generate parting surfaces(PS) for an injection mold design. We used a Face-Edge Graph which can be made by B-rep information of solid model. The graph is useful for finding the peripheral-loop edges for PL and the inner-loop edges for hole-patch. The PS can be generated automatically by selecting pre-defined direction lines. We can create a core and cavity molds by trimming the raw stock block with the PS and the upper/lower faces of a product model. We implemented proposed method with Unigraphics API functions and C language, and tesed on Unigraphics V15.

In recent days, Internet advertising effects are expanded by the steep increase of the Internet users and the extension of the advertising market will be accelerated through Internet. This paper indicates the importance of Internet advertising and suggests the solution of a network advertising service. The system is divided into an Advertise Server, an Advertiser and a Web Publisher. This study proposes both the collection and the analysis of traffic data in real time. Also, the banner advertising frames not for sale purpose are levelled for the impression using the solution for the banner exchange engine. In addition, with developing the advertising service system by using Active Server Pages, the newest language of server side script will be able to lead the additional supplement of more various profitable functions when it is considered the rapid increment of Active Server Pages.

This paper proposes a design procedure to develop the object-oriented simulator of port container terminal. The design methodology uses an object-oriented approach to support an object-oriented simulation and the design procedure consists of object scheme and event scheme. The object-scheme is a procedure to determine the structure of material flow objects and information flow objects and a relation diagram between objects that have attributes and methods. The event scheme is a procedure to define methods and to connect messages of objects. We assume that the container terminal system consists of gate, container yard, and berth and the equipment used in the container terminal are container cranes, transfer cranes, yard tractors, and trailers.

In this paper, we place the focus on suggesting a method of forecasting demand for PCS resale service with survey data in Korea. It is important for the service provider to forecast the diffusion process when designing marketing strategies and analyzing the costs and benefits. For the reason, we conduct a survey of three groups composed of non-subscribers, cellular subscribers, and PCS subscribers in order to forecast the demand according to several possible scenarios and business strategies. We consider the survey item that is measured by multiple point scales in response to a question if he would subscribe to the mobile telephone service in the future. We propose a method to forecast the size of market potential by classifying each individual into the two extreme groups, that is, yes or no. Then, by integrating survey data and historical data, we forecast the demand for PCS resale service that varies according to scenarios and strategies. From the results, we can find several implications for the provider of PCS resale service.

During last ten years, logistics network management has become one of the most important sources of competitive advantage regarding logistics cost and customer service in numerous business segments. The key to success in this dynamic and severe business environment is the ability to design and plan the logistics network optimally in an integrated way. Network design and planning involves many issues relating to strategic, tactical, and operational decisions. To assist a logistics designer or planner, many computer-based decision support systems (DSS) have been developed. In this paper, the issues related to design, development, and implementation of the DSS for logistics network design and planning are discussed, and an ideal framework of the DSS is proposed with some ideas on the future development. Finally, DLNET, the DSS developed by author, is briefly introduced.

Virtual manufacturing systems that perform production activities ahead of real production in virtual world can reduce time and cost to develop, design, plan, and manage new products. In this paper, a virtual manufacturing system is constructed as a tool to support decision making by using VRML and Java. The basic structure of the virtual manufacturing system and the operation models are also presented. The developed system helps any related persons to share design and manufacturing information, and to perform their tasks collaboratively through Internet. The other function of the system is to monitor operation status in real time.

We developed an efficient small sized weather condition forecasting system (WFS). A cheap NT-server was utilized for handling a large amount of data, while traditional WFS has conventionally relied on Unix based workstation server. The proposed WFS contains automatic weather observing system (AWS). AWS was designed for collecting weather conditions automatically, and it was linked to WFS in order to provide various weather condition information. The existing two phase scheme and chain code algorithm were used for transforming AWS's data into WFS's data. The WFS's data were mapped into geometric information system using various display techniques. Finally the transformed WFS's data was also converted into JPG (Joint Photographic Group) data type, and the final JPG data could be accessible by others though Internet. The developed system was implemented using WWW environment and has provided weather condition forecasting information. Real case is given to show the presented integrated WFS with detail information.

Seasonal variation of natural gas demand coupled with rigid and stable import pattern of gas represents the characteristic feature of the Korean Liquified Natural Gas(LNG) industry. This attribute has required a huge amount of investment for the construction of storage facility. Thus, to minimize the supply cost, it is legitimate to reduce storage requirement itself. In this study, we combine three alternative methods to deal with the storage requirement to minimize the supply cost. Those are (1) adding additional storage tanks, (2) inducing large firm customers, and (3) constructing gas-turbine self generation facilities. Methodologically, we employ the mixed integer program (MIP) to optimize the system. The model also consider demand and price-setting scheme in separate modules. From the results, it is shown that if alternatives are combined optimally, a number of storage tanks can be reduced substantially compared with the original capacity plan set by the industry authorities. We perform various sensitivity analyses to check the robustness of the results. The methodology presented in this study can be applied to the other physical network industry, such as hydraulics. The empirical results will shed some light on the rationalization of capacity planning of the Korean natural gas industry.

Recently, due to the primary emphasis of environmental problem, the proper selection of the prevention technology systems necessary for Dioxin treatment has been one of the critical issues in the industrial sector. This paper shows how an Analytic Hierarchy Process(AHP) model can be used for assessing the performance of selected prevention technology systems: SDA/BF-SCR, SNCR-SDA/BF, SDA/BF, EP-WS-SCR, ED-WS, and EP-SCR-WS essential for Dioxin treatments. The final results show that SNCR-SDA/BF is the most attractive prevention technology system to use in an incinerator system, followed by SDA/BF-SCR, SDA/BF and EP-WS-SCR. This is consistent with the information that we found with respect to the elements that were taken into consideration. Sensitivity analysis is also provided here.

The objectives of this research are to establish the operation scheduling and the preventive maintenance system in order to optimize the operation of mailing center. For the optimal operation scheduling of mailing process, the existing workflow of mailing process and that of required time are investigated prior to simulation modeling. The simulation experiments are conducted to increase the nextday delivery rate. The best alternative whose nextday delivery rate up to 100% is selected based the AHP(Analytic Hierarchy Process) method. The optimal work scheduling of all mailing centers are also presented. In addition, the CMMS(Computerized Maintenance Management System) for preventive maintenance is introduced for efficient operation of highly automated facilities of mailing center.

We analyze IS0 9001 audit data and add-on requirements data collected by leader assessors from three leading Korean furniture companies for around three years. We plot a Pareto chart and test the homogeneities for the number of non-compliances and improvement notes across companies. We also fit the data to a loglinear model. Some recommendations with regard to add-on requirements are suggested. The recommendations should be added to IS0 9001 requirements to specifically implement an efficient QMS in Korean furniture industry.

For the graceful transition from the analog to digital TV systems, a systematic frequency assignment scheme must be incorporated into the transition planning procedure. In this study, we have studied the frequency assignment methodology for the efficient management of the limited spectrum resources. By applying the graph-theoretic approach, this study developed a new solution method for additional frequency assignment problem whose objective is to assign available frequencies for newly generated requirements (digital TV stations) with minimum reassignment of the preassigned frequencies to LPTV stations while meeting the interference-related constraints. The proposed algorithm can be effectively applied not only to the current digital TV introduction phase but also to the development phase with some further development. This study can be utilized as the basis for the future study on frequency assignments that aims at graceful transition from analog TV to digital TV.

In manufacturing processes, manufacturing features always deviate somewhat from their nominal design specifications due to several types of errors. This study suggests a fitting algorithm of the geometric profile parameters of leading and trailing edges for turbine compressor airfoils. In reality, industry personnels inspect the airfoil profile by trial-and-error method to determine the geometric feature parameters. In this study we propose an exploration approach based on factorial design with center point to minimize the effect of measurement errors caused by probe slip. By adopting the fitting method developed in this paper, one can enhance the precision and efficiency of fitting the airfoil edge profile.

In this paper, We analyze a capacity dimensioning and performance of the access line to the X.25 packet network when the AO/DI internet service is connected via D-channel. We show the forecasting methodology of the traffic demand of the D-channel internet services when the TDX-1OA switching system accommodates the target number of subscriber. Based on the traffic demand forecast, the required capacity of the access line is suggested to prevent bottleneck problem in the access line to the X.25 packet network.

In this paper, an integrated system of optimal design, performance evaluation, and die design and manufacturing of axial fans for cooling tower is presented. The design and performance evaluation are developed based on three dimensional flow analysis so as to ensure low noise and high efficiency. The methodologies are implemented on computer as a GUI system including 3-D surface modeling and 2-D drawing file output modules. The CAD/CAM system is engaged to design the die and generate NC tool path, but the processes are also automated and integrated into the system by means of a part program coded from the design data. It is shown that the newly developed fans have superior performance and shortened lead-time compared to the existing dead-copied fans.

This paper deals with the design and the development of user interface for a high speed linear programming solving system. The general users' educational and practical requirements are analyzed and the functionalities that should be implemented for the requirements are designed. The user interface of the system consists of various carefully designed built-in commands that perform the functionalities. The names of the build-in commands are chosen to enhance the users' convenience. We also address the various factors that should be considered in the design of the linear programming solvers when integrated with the user interface. As one of user-friendly environments, data input system that can understand user-written arithmetic form is added to our user interface system. Finally, we compare our system with other user interface systems.

This Paper presents a method for unfinished work transition probability distribution of modulated $n^*D/D/l$ queue with overload period. The Modulated $n^*D/D/l$ queue is well known as a performance analysis model of ATM multiplexer with superposition of homogeneous periodic on-off traffic sources. Theory of probability by conditioning and results of $N^*D/D/l$ queue are used for analytic methodology. The results from this paper are expected to be applied to general modulated $n^*D/D/l$ queue.

This paper evaluated the 12 sensory measures suitable for evaluating taste of kimchi stored for 64 maturing days in the three kimchi refrigerators each made by the three different electronics companies respectively. The panel composed of 6 married women and 6 married man tasted sample of kimchi 8 times during the 64 maturing days. Analysis of variance results showed that among the 12 sensory measures sour smell, fresh smell, fermenting smell, sour taste, fresh taste, sensory satisfaction, and maturing degree were sensitive to differentiate both maturing days and refrigerators. Among sensory measures, maturing degree showed the most consistently increasing pattern during maturing days and the most consistently differentiating pattern for the refrigerators.

Situation awareness is defined as a person's perception of the elements of the environment within a volume of time and space, the comprehension of their meaning and the projection of their status in the near future. Situation awareness is important in attempting to evaluate human behavior in operating complex systems such as aircraft, air traffic control, and nuclear power plant systems. From the literatures this study reviews the relationship between situation awareness and numerous individual, system and environmental factors, and also reviews the methodologies for the empirical measurement of situation awareness applicable to Korea Next Generation Reactor (KNGR) design project. Attention, working memory, workload, stress, system complexity, and automation are presented as critical factors limiting operator's situation awareness. Mental models and goal-directed behavior are hypothesized as important mechanisms overcoming these limits. This study summarized hypothesized guidelines for interface design to improve situation awareness of reactor operators. Some of the guidelines should be tested in the KNGR evaluation experiments in the future.