• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.12 no.8
• /
• pp.782-790
• /
• 2000

A numerical study has been conducted to characterize the transient pressure in a building water supply system with an air chamber by utilizing a commercial code that employs the method of characteristics. Some results produced for the purpose of verification in the study agree quite well with the previously reported. Several parameters are then varied. Among them are the valve closure time, the wave speed, the static pressure, the polytropic exponent, the air chamber volume, the inner diameter and the shape of orifice in the air chamber, etc, while the water temperature and velocity are kept constant at $20^P{circ}C $,/TEX> and 0.8 m/s, respectively, Results reported in this parametric study may be useful to understand the unsteady behavior of the system.

• 한국IT서비스학회:학술대회논문집
• /
• 2006.05a
• /
• pp.134-141
• /
• 2006

Today, the role of IT is so important that it is regarded as a partner of business, not a simple supporter. The more important the role of IT becomes, the higher the level of business needs rises and the more customers want. In the market of IT, more and more enterprises are establishing ITSM processes based on the ITIL for these environments: however they are experiencing the processes of trial and errors because of the shortage of references To improve these problems, in this study, we developed the ITSM model defined by investigation of the instance to which we have applied the ITIL Continuous Service Improvement Process which contains five phases such as High level Business Objectives. Assessment. Measurable Targets, Process Improvement, Measurement and Metrics. This model is an ITSM building framework to understand the concepts over the length and breadth of ITIL and minimize the trial and errors appearing during the building of the ITSM processes, and this paper presents a plan to develop the frameworks.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.4
• /
• pp.793-803
• /
• 1997

Open networking architecture is required to support new multimedia services as integrated functions of network management and service architecture. In this paper, we propose the methodology of building block modeling using object grouping concepts and the sharing scheme of different distributed processing environments based on open networking architecture. The building block has the functions of object management, security object instance registry and object mapping in object group. It is necessary for the connection management information to be shared on the interworking between two domains. We implemented and validated connection management functions using computational object modeling and building block modeling in different distributed processing environments.

• Journal of KIBIM
• /
• v.5 no.2
• /
• pp.1-11
• /
• 2015

Despite a lot of research on BIM, there is no quantitative study to measure accurately the performance of BIM coordination service. Thus, this study suggested method to measure the performace of BIM coordination services, applying queueing models in the field of management science. To analyze queuing system of BIM coordination services, a group of BIM coordinator were selected. Through focus group interviews with experts were used in the analysis to derive mean arrival rate(${\lambda}$), mean service rate(${\mu}$) of BIM coordination services. Single-server queuing model(M/M/1), multiple server queuing model(M/M/s) is utilized for the BIM coordination services performance measurement in construction phase. This study has significant quantitative performance measurement approaches that can be utilized in the decision-making for the improvement of the BIM coordination services and to support the review of the alternatives accordingly. But There is a limit but it is difficult to take into account the increase or decrease of the cost of alternatives according to the review.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2005.05a
• /
• pp.1033-1039
• /
• 2005

Parallel and distributed simulation is concerned with the efficient execution of large-scale discrete event simulation models on multiprocessors and distributed platforms. After the development of WWW, many efforts in the parallel and distributed simulation have been made for modeling, particularly building simulation languages and creating model libraries that can be assembled and executed over WWW. However, web-based parallel and distributed simulation is restricted by heterogeneous computing environments. Recently, the advent of XML and web services technology has made these efforts enter upon a new phase. Especially, the web services as a distributed information technology have demonstrated powerful capabilities for scalable interoperation of heterogeneous systems. This paper aims to develop and evaluate the parallel and distributed simulation using the web services technology. In particular, a prototype multi-pass simulation framework is implemented using Java-based web services technology. It focuses on the efficiency of multi-pass simulation used for optimization through the distribution of simulation replication to several simulation service providers. The development of parallel and distributed simulation using web services will help solve efficiently large-scale problems and also guarantee interoperability among heterogeneous networked systems.

• Journal of Information Processing Systems
• /
• v.3 no.2
• /
• pp.82-88
• /
• 2007

Web services are the new building block of today's Internet, and provides interoperability among heterogeneous distributed systems. Recently in web services environment, security has become one of the most critical issues. The hackers attack one of fragile point and can misuse legitimate user privilege because all of the connected devices provide services for the user control and monitoring in real time. Also, the users of web services must temporarily delegate some or all of their rights to agents in order to perform actions on their behalf. This fact risks the exposure of user privacy information. In this paper, we propose secure delegation model based on SAML that provides confidentiality and integrity about the user information in distributed systems. In order to support privacy protection, service confidentiality, and assertion integrity, encryption and a digital signature mechanism is deployed. We build web service management server based on XACML, in order to manage services and policies of web service providers.

• Journal of Korean Society of Rural Planning
• /
• v.25 no.2
• /
• pp.23-33
• /
• 2019

The study aims to measure the quality of consulting services for village-building projects in rural areas. To this end, the government wanted to analyze the impact of the quality of service on residents' satisfaction and business performance in villages that are receiving consulting services. As a result of the empirical analysis of the case areas, the five-dimensional tangibles, reliability, assurance and empathy of the quality of consulting services in rural villages had a defining influence on the residents' satisfaction. And the residents' satisfaction of consulting services had a defining influence on the business performance of the village with tangibles, reliability, and assurances. The main implications presented on the basis of these results were analyzed that it was necessary to universalize the assessment of service quality, to strengthen the burden of the village on the cost of consulting services, and to induce participation through a sufficient understanding of the villagers' business.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2007.11a
• /
• pp.25-30
• /
• 2007

• Proceedings of the SAREK Conference
• /
• 2004.11a
• /
• pp.60-60
• /
• 2004

• Journal of Computing Science and Engineering
• /
• v.6 no.2
• /
• pp.168-177
• /
• 2012

The search for relevant and actionable information is a key to achieving clinical and research goals in biomedicine. Biomedical information exists in different forms: as text and illustrations in journal articles and other documents, in images stored in databases, and as patients' cases in electronic health records. This paper presents ways to move beyond conventional text-based searching of these resources, by combining text and visual features in search queries and document representation. A combination of techniques and tools from the fields of natural language processing, information retrieval, and content-based image retrieval allows the development of building blocks for advanced information services. Such services enable searching by textual as well as visual queries, and retrieving documents enriched by relevant images, charts, and other illustrations from the journal literature, patient records and image databases.