• Journal of the Korea Society for Simulation
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• v.15 no.3
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• pp.11-21
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• 2006

Importance of and need for grid resource management have accelerated in accordance with increasing development of grid computing. However, it is very complex to distribute and utilize resources efficiently in geographically dispersed environments. This is due to the different access policies and constraints of grid resource owners. Users request resources according to their needs. Operators of a grid computing system need to be able to monitor the system states for reflecting these demands. So, a grid computing system needs a resource management policy that monitors states of resources and then allocates resources. This paper proposes a user demand-based grid trade management model that provides an efficient resource management by the trade allocation based on a users' demand and providers' supply strategy. To evaluate performance, this paper measures increasing rate of resource trades, average response time of trades, and processing time utilization. Firstly, the average increasing rates of trade are 585.7% and 322.6% higher than an auction model and a double auction model. Secondly, the average response time of the user demand-based grid trade management model is maintained between 3 and 5 simulation time. Finally, it is found that the processing time utilization is an average of 145.4% and 118.0% higher than an auction model and a double auction model. These empirical results demonstrate the usefulness of the user demand-based grid trade management model.

• Journal of Korea Port Economic Association
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• v.36 no.3
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• pp.55-74
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• 2020

With globalization and the development of information and communication technology, the supply chain is becoming more widespread and complex, which increases the occurrence and damage caused by supply chain risks. Supply chain risk management has a great impact on corporate performance through the analysis of risk factors and proactive and strategic approaches. This study aims to analyze the effects of supply chain risk factors on risk management strategies and corporate performance empirically. In the research model for empirical analysis, supply chain risk factors were classified into supply, demand, operation, network, and external environment, while the risk management strategies were divided into active and passive strategies, as well as financial and operational performance for corporate performance. The data obtained via the questionnaire were analyzed for the path of the structural equation model. As a result of the analysis, companies are actively pursuing risk management for internal risk factors, rather than external factors, in terms of internal and external risk factors, and it was found that these strategies have a significant effect on corporate performance. Therefore, in the future, companies should conduct risk management strategies more proactively and preemptively through a thorough analysis of various risk factors affecting business operations.

• Journal of Korea Port Economic Association
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• v.32 no.4
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• pp.1-13
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• 2016

This study attempts to establish a precise forecast model for the container inventory demand of shipping companies through forecasts based on equipment type/size, ports, and weekly system dynamics. The forecast subjects were Shanghai and Yantian Ports. Only dry containers (20, 40) and high cubes (40) were used as the subject container inventory in this study due to their large demand and valid data computation. The simulation period was from 2011 to 2017 and weekly data were used, applying the actual data frequency among shipping companies. The results of the model accuracy test obtained through an application of Mean Absolute Percentage Error (MAPE) verified that the forecast model for dry 40' demand, dry 40' high cube demand, dry 20' supply, dry 40' supply, and dry 40' high cube supply in Shanghai Port provided an accurate prediction, with $0%{\leq}MAPE{\leq}10%$. The forecast model for supply and demand in Shanghai Port was otherwise verified to have relatively high prediction power, with $10%{\leq}MAPE{\leq}20%$. The forecast model for dry 40' high cube demand and dry 20' supply in Yantian Port was accurate, with $0%{\leq}MAPE{\leq}10%$. The forecast model for supply and demand in Yantian Port was generally verified to have relatively high prediction power, with $10%{\leq}MAPE{\leq}20%$. The forecast model in this study also had relatively high accuracy when compared with the actueal data managed in shipping companies.

• Proceedings of the Korea Information Processing Society Conference
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• 2006.11a
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• pp.27-30
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• 2006

이 논문에서는 에이전트 기반의 시스템에서 책임행위와 제도를 활용한 의사소통의 체계를 구축할 수 있는 방안과 예를 제안한다. 또한 주요 관리요소로서의 제도와 에이전트들간의 상호작용을 모델링하는 책임행위를 가능하게 하는 분산 모델을 제안한다. 이러한 분산 모델을 위해 공급망 관리 시스템을 예로써 설명한다.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.403-406
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• 2006

본 연구에서는 양극의 two-phase simulation 모델을 확립하고 GDL 물성과 작동조건이 전지성능에 미치는 영향에 대해 시행하였다. 모델로는 Multi-phase $mixture(M^2)$ 모델을 사용하였는데 이 모델은 각 상의 balance식을 하나의 mixture-phase식으로 통합하여 수학적 계산이 용이할 뿐만 아니라 실제 전지 성능에 매우 근사하여 신뢰성성도 확보할 수 있었다. 최적의 GDL 구조와 작동조건을 규명하기 위해 기체투과도, 접촉각, 기공도, 기체 공급가스 차이에 따른 전지 성능 분석을 시행하였는데 그 결과 모든 파라미터들이 증가할수록 비례적으로 전지 성능이 증가하였다. 기체 공급가스>기공도>>접촉각>기체투과도 순으로 전지에 미치는 영향이 큰 것으로 나타났다.

• Management & Information Systems Review
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• v.31 no.1
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• pp.167-182
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• 2012

Recently, interesting of u-city with ubiquitous computing technologies has increased. In this paper, we propose u-service model for urban facility management based on ubiquitous computing technologies. To propose the research purpose, we define business model for the service and u-service model. And, we propose service function, service process, and relationships between participants to give shape to u-service model. First, we present five service functions; remote monitoring, remote control and inquire, state information, field support, and facility history information. And, we propose overall service process and demand-supply relationship between participants.

• Journal of the Korea Society of Computer and Information
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• v.14 no.12
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• pp.41-53
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• 2009

In this paper, we propose the system structure and technologies to implement a business model for an intelligent traffic facility management system based on ubiquitous technology. The business model includes the service functions, service structure, business process, and demand and supply relationship among the participants in this model. We also propose an approach to implementing the model. This includes the network, infrastructure and platform to be used for system composition. We then present the results from an analysis by comparison of different technologies and an adequate technology structure. Finally, this paper may present guidelines to managing traffic facilities.

• Korean Journal of Construction Engineering and Management
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• v.10 no.2
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• pp.46-54
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• 2009

In the early 90s, we had serious shortage of construction engineers for the expansion of construction market. So, Government has established the admitted engineer system in 1995. However, since year 2000, while the engineershortage has been resolved, the opposite situation has occurred: serious over-supply of construction engineers. Therefore, Government announced that would abolish the admitted engineer systems as recognized the existent admitted engineers from 2007. From this point of view, it is critical to make the accurate forecast of number of required construction engineers for providing the basis for the most appropriate policy from 2008 to 2017. This research have developed a construction engineer supply-demand forecast model based on the GDP and construction market analysis. The results of this research will be applied to the basic data that policy planner establishes the supply-demand policy of construction engineers.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.565-568
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• 2004

최근 ERP에 고객관계관리(CRM), 공급망관리(SCM), 지식관리(KMS) 등의 기능을 확장한 확장형 ERP에 대한 연구개발이 활발해지고 있다. 그러나 타산업과 달리 건설산업의 특수성으로 인한 정보화의 부진으로 인해 이러한 새로운 개념을 적용할 수 있는 ERP 확장모델이 없는 상태이며, 대기업의 경우 일부 이러한 모듈을 부분적으로 적용하려는 움직임은 보이고 있으나, ERP와 별도의 이종시스템으로 관리되고 있어 통합적인 ERP운용을 통해 얻을수 있는 효과를 기대하기 어려운 실정이다. 이에 본 연구에서는 산자부에서 건설표준ERP템플릿으로 지정받은 ERP엔진을 모체로 협력업체와의 인터페이스 제공을 위한 협업적IT시스템과 전자계약시스템, 그리고 변화되는 ISO에 대한 기업의 대처능력 향상을 위한 ISO인증관리시스템, 고객과의 관계관리를 위한 고객관계관리시스템, 절차서와 같은 기업 내의 표준화 된 문서를 관리하기 위한 전자매뉴얼관리시스템, 결재관리를 위한 그룹웨어, 기업 내의 지식저장소 관리를 위한 지식관리시스템을 연구범위로 하여 건설분야 확장형ERP 모델(E2CM)을 개발하였으며, 이를 검증을 위한 시스템(eCOMIS)을 개발하였다.

• Journal of Korea Port Economic Association
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• v.32 no.1
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• pp.165-178
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• 2016

Container port nowadays becomes one of the most vital link of the transportation chain, plays an important role in trading with other countries. Therefore, evaluating the operational efficiency of container ports to reflect their status and to reveal their position in this competitive environment is very important for port development. Although there have been lots of methods used to measure efficiency in the past, the DEA (Data Envelopment Analysis) model is still the most commonly applied approach. However, the data used in the model sometimes is complex and uncertain to handle using the basic DEA model. In this paper, we applied an uncertainty theory to create an uncertainty DEA model (UDEA), which can solve the limitation of the traditional one. This study mainly focuses on measuring efficiency of 41 container ports by applying proposed an UDEA model. The results show that among 41 container ports, only six container ports are regarded to have efficient operation through the clustering, meanwhile others have technical and scale inefficiencies. We found out that an UDEA model is better to analysis efficiency than existing DEA model.