• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2004.05a
• /
• pp.441-445
• /
• 2004

In this paper, we deal with an inventory model of a multi-stage, serial supply chain system where a single product type and nonstationary customer demand pattern are considered. The retailer and suppliers place their orders according to an echelon-stock based replenishment control policy. We assume that the suppliers can access online information on the demand history and use this information when making their replenishment decisions. Using a reinforcement learning technique, the inventory control parameters are designed to adaptively change as the customer demand pattern is altered, in order to maintain a given target service level. Through a simulation based experiment, we verified that our approach is good for maintaining the target service level.

• Proceedings of the KSR Conference
• /
• 2009.05a
• /
• pp.721-729
• /
• 2009

Recently, there has been growing necessity to estimate the future travel demand of high speed train because the circumstance of high speed train service is rapidly changing with the launching of 2011 second stage of Gyeongbu high speed railway(Dongdaegu-Busan) and the completion of 2014 first stage of Honam high speed railway(Yongsan-Gwangju), etc. This study was designed to estimate future travel demand by analyzing the transport performance and train service characteristics of Gyeongbu and Honam line. This study presents the maximum load section and the changed future travel demand, which will be applied to establish a train operation plan.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.663-665
• /
• 2004

There are some demand response program which is Direct Load Control and so on in Korea. These are used to manage lack of power stability or shift peak time for shading load. It is very important not only using stability power system but controling and scheduling power system on the whole. Interruptible loads are essential resources to solve lack of energy and limit of constructing generator On recently days, Demand Response Program's reliability is recognized as ancillary or reserve service in many country. This paper presents a necessity to apply demand resource to our ancillary program. For this reason, it is introduce overseas ancillary program using load resource.

• International Journal of Highway Engineering
• /
• v.14 no.3
• /
• pp.163-171
• /
• 2012

Demand Responsive Transit (DRT) services are becoming necessary as part of not only alternative transportation means for elderly and mobility impaired passengers, but also sustainable and flexible transportation options in urban area due to the development of communication technologies and Location Based Services (LBS). It is difficult to investigate the system performance regarding vehicle operational schemes and vehicle routing algorithms due to the lack of commercial software to support door-to-door vehicle simulation for larger area. This study proposes a simulation framework to evaluate innovative and flexible transit systems focusing on various vehicle routing algorithms, which describes data-type requirements for simulating door-to-door service on demand. A simulation framework is applied to compare two vehicle dispatch algorithms, Nearest Vehicle Dispatch (NVD) and Insertion Heuristic (IH) for real-time shared-taxi service in Seoul. System productivity and efficiency of the shared-taxi service are investigated, comparing to the conventional taxi system.

• Journal of Labour Economics
• /
• v.36 no.1
• /
• pp.93-129
• /
• 2013

Analyzing the change in consumption pattern depending on the employment of married women, the spendings in transportation, education, and dining out are increased. The change in consumption patterns depending on the increase of dual-income family can be seen as the increased demand of market service that replaces the household production service. Especially when the employment of married woman from high income class(highly educated, middle-class, upper-class) is increased, they tend to get employed in more professional and highly skilled industries, which leads to higher effect on employment induction, and consequently increasing the labor demand for low-skilled service industry.

• Journal of Information Science Theory and Practice
• /
• v.10 no.spc
• /
• pp.154-163
• /
• 2022

The purpose of this paper is to illuminate the role and importance of National Research & Education Network (NREN) in the national research and education field and to establish the future strategy of KREONET in Korea. To this end, we first carefully analyze the footsteps of NREN in major overseas countries, KREONET achievements, and future demand for KREONET. The history of NREN's development is divided into the 2000s, 2010s, and present by era, and classified into network infrastructure, network service, and next-generation network technology by subject. KREONET achievements are divided into advanced research support, network backbone and operation, and network service. Future demand analysis of users who use KREONET was conducted through Korea Research International Incorporation, a survey company. This paper presents the future development strategy of KREONET by analyzing KREONET achievements and future demand.

• Proceedings of the CALSEC Conference
• /
• 2004.02a
• /
• pp.51-55
• /
• 2004

·Web Service 적용 -비용절감/새로운 Revenue 창출 기회 ·Business 환경 -SOA(서비스기반구조), 온디맨드, 그리드 컴퓨팅의 기반→Web Service로의 이행 가속화 ·IT Challenge -복잡성과 위험 ·관리 솔루션 -전반적인 관리 요구 -인프라 ＆ Web Service 레벨 ·Web Service 관리 기대 효과 -효율성, 일관성 및 안전성 제공 -근본 원인 분석 기반 제공

• Journal of Korean Institute of Industrial Engineers
• /
• v.30 no.2
• /
• pp.93-106
• /
• 2004

This paper studied a maximal covering location problem with cost restrictions, to maximize level of service within predetermined cost. It is assumed that all demand have to be met. If the demand node is located within a given range, then its demand is assumed to be covered, but if it is not, then its demand is assumed to be uncovered. An uncovered demand is received a service but at an unsatisfactory level. The objective function is to maximize the sum of covered demand, Two heuristics based on the Lagrangean relaxation of allocation and decoupling are presented and tested. Upper bounds are found through a subgradient optimization and lower bounds are by a cutting algorithm suggested in this paper. The cutting algorithm enables the Lagrangean relaxation to be proceeded continually by allowing infeasible solution temporarily when the feasible solution is not easy to find through iterations. The performances are evaluated through computational experiments. It is shown that both heuristics are able to find the optimal solution in a relatively short computational time for the most instances, and that decoupling relaxation outperformed allocation relaxation.

• Journal of Digital Contents Society
• /
• v.13 no.4
• /
• pp.477-482
• /
• 2012

The mVoIP service is the technology which focuses on the wireless data service as the IP network having the transmission rate of 100 Mbps classes on the high-speed middle of movement through the WiFi, WiBro and 3G mobile radio communication network, and etc. and is developed. Since 2010, the mVoIP (mobile VoIP) service shows the rapid growth due to 4G-LTE service seriously disclosed from July with the Smart phone and 2,011 it begins to be rapidly popularized. In this research, additionally the mVoIP service industry activation plan is presented with the trends of technology development including the chip-set/module/terminal, etc. based upon local and foreign market trend searchlight through the market demand analysis. The mVoIP service downloads App to the mobile apparatus and or can provide the service as the software through the WiFi network. Therefore, the change which is large in the products development aspect is to be have no. Expected to is being provided as the added service in the case of 4G-LTE as a matter of course, the service deployment where it is based on the market principle and demand needs is needed.

• Journal of the Korean association of regional geographers
• /
• v.2 no.1
• /
• pp.1-24
• /
• 1996

This paper is a case study on regional linkages of producer services in Chinju region. Producer service appeared as the most rapid growth sector in service industry. In Chinju region. manufacturing firms purchase generalized producer service within the region. However the higher-order service, they demand; the remoter metropolis especially Seoul, they depend on. Linkage patterns among manufacturing sectors are similar; but then the firms whose managers are from Chinju or Gyeong-nam region had stronger regional linkages than others. Public institute such as Chamber of Commerce & Industry, University Research Institute of Industrial Technology. Korea Technology Credit Guarantee Fund, Korea Silk Research Institute have made important role as suppliers of public producer services in Chinju Region. As present stage, their services of industrial technology, fiancing, and information are not only fit regional demand but also spatially limited within region. The facts that large firms purchase high-order services from other region and small firms have not good demand of producer service suggest regional policy implication about supplying relevant producer service in the region.