• ETRI Journal
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• v.21 no.3
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• pp.6-15
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• 1999

Many studies in the software reliability have attempted to develop a model for predicting the faults of a software module because the application of good prediction models provides the optimal resource allocation during the development period. In this paper, we consider the change request data collected from the field test of the software module that incorporate a functional relation between the faults and some software metrics. To this end, we discuss the general aspect if regression method, the problem of multicollinearity and the measures of model evaluation. We consider four possible regression models including two stepwise regression models and two nonlinear models. Four developed models are evaluated with respect to the predictive quality.

• Proceedings of the Korea Association of Information Systems Conference
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• 1996.11a
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• pp.199-204
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• 1996

It is discussed how to determine the home location of idle vehicles in an AGVS with a loop guide path in a way of maximizing the request-call response probabilities for all demand. Optimal home position is selected by solving the simultaneous equations easily. Static positioning strategy is analyzed in which a single home position is allocated to which every vehicle is routed whenever it becomes idle. The cases of unidirectional guidepath is considered only. We provide a numerical example to illustrate the search algorithm developed for the case and compare the searched optimal solutions with the others.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.95-96
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• 2015

This paper aims to identify patterns in users' requests for facility management (FM) services in higher education facilities. We analyzed data collected from 309 service request forms, made available via a department office and an enterprise resource planning system, at a private university in Seoul between May 2009 and February 2015. We found that the number of user requests were the highest in September and October. Requests for electronic and communication (E/C) services outnumbered those for architectural services and mechanical and plumbing (M/P) services. Repair requests for doors and windows were the most common under architectural services; repairs for air-conditioners and radiators were the most commonly under M/P services; and installation of electrical outlets, telephone wires, and internet services were the most sought-after E/C services. Maintenance requests were received every three months, while repair requests were received every six or seven months.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.41
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• pp.51-60
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• 1997

In this paper, A Connection Admission Control(CAC) algorithm by Dynamic Bandwidth Allocation is proposed. The B-ISDN will be required to carry traffic generated by a various traffic sources. These source will have all traffic flow characteristics and quality of services requirements. When a connectionless message with burstiness arrives at a node during a renewal period, CAC will be dynamically determined connection request by using the predetermined connection admission bounds in estimating the number of input arriving cells. The proposed algorithm estimates the available bandwidth by observing cell streams of the aggregate traffic. A connection request is accepted if the available bandwidth is larger than declared peak rate, and otherwise rejected. The proposed CAC scheme is shown to be promising and practically feasible in obtaining efficient transmission of burst traffic with guaranteed quality of services.

• IE interfaces
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• v.13 no.3
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• pp.416-423
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• 2000

This paper considers a web-based order processing system under SCM environment. Following the framework of B2B electronic commerce, we focus on activities closely related to order handling within the supply chain. We also try to integrate the order processing system with the overall information system of the company. The methodology is applied to the case of H company and a prototype system is designed. This study analyzes the current product estimate and order handling process in the point of view of both the purchasing and the selling companies. It intends improvement by changing the existing closed way of request and offering estimate through fax or VAN into an open way using internet. For this, a company should be registered on the order site of internet. Then it can request estimate, take estimate, and handle order through internet adopting the concept of electrical commercial transaction.

• Journal of Korea Multimedia Society
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• v.8 no.12
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• pp.1597-1604
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• 2005

Recursive Patching is an efficient multicast technique for large-scale video on demand systems and recursively shares existing video streams with asynchronous clients. When Recursive Patching initiates a transition stream, it always makes a transition stream have additional data for the worst future request. In order to share a VOD server's limited network bandwidth efficiently, this paper proposes Practical Patching that removes the unnecessary data included in the transition stream. The proposed Practical Patching dynamically expands ongoing transition streams when a new request actually arrives at the server. As a result, the transition streams never have unnecessary data. Simulation result confirmed that the proposed technique is better than Recursive Patching in terms of service latency and defection rate.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.3
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• pp.158-164
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• 2000

In recent year, desire and request fer micro automation are growing rapidly covering the whole range of the industry. This has been caused mainly by request of more accurate manufacturing process due to a higher density of integrated circuits in semiconductor industry. This paper presents a six d.o.f fine motion stage using magnetic levitation technique, which is one of actuating techniques that have the potential for achieving such a micro motion. There is no limit in motion resolution theoretically that the magnetically levitated part over a fixed stator can realize. In addition, it Is possible to manipulate the position and the force of the moving part at the same time. Then, the magnetic levitation technique is chosen into the actuating method. However, we discuss issues of design, kinematics, dynamics, and control of the proposed system. And a few experimental results fur step input are given.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06a
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• pp.510-513
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• 2011

Green IT의 실현을 위해 컴퓨팅 에너지 소모를 최소화 하고 전력 효율을 높이고자 하는 연구가 활발하게 진행되고 있다. 이러한 연구는 단일 시스템에서 데이터 센터와 같은 다중 시스템 레벨로 점차 확대되고 있는데 데이터 센터에서는 전력 절감을 위해 정책을 수립하는 방법으로 Green IT를 실현하게 된다. 대다수의 전력 절감 정책은 하드웨어 디바이스의 전력 상태를 상황에 맞게 변경시키는 방법을 사용한다. 하지만 디바이스의 빈번한 전력 상태 변경은 추가적인 전력과 컴퓨팅 오버헤드를 발생시키고, 서비스 품질과 직결되는 성능 저하의 문제를 야기할 수 있다. 따라서 본 논문에서는 데이터 센터를 구성하는 각각의 단일 시스템에서 OS를 통해 수집 가능한 정보를 기반으로 요청되는 서비스에 따라 추가적인 오버헤드 없이 처리할 수 있는 시스템을 찾고 작업을 분배하는 기법을 제안한다.

• International Journal of Contents
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• v.4 no.2
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• pp.13-18
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• 2008

A load sharing algorithm is one of the important factors in computer system. In sender-initiated load sharing algorithms, when a distributed system becomes to heavy system load, it is difficult to find a suitable receiver because most processors have additional tasks to send. The sender continues to send unnecessary request messages for load transfer until a receiver is found while the system load is heavy. Because of these unnecessary request messages it results in inefficient communications, low cpu utilization, and low system throughput. To solve these problems, we propose a self-adjusting evolutionary algorithm for improved sender-initiated load sharing in distributed systems. This algorithm decreases response time and increases acceptance rate. Compared with the conventional sender-initiated load sharing algorithms, we show that the proposed algorithm performs better.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.1
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• pp.110-117
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• 2001

In this paper we researched the homepage automation system and its implementation methods that made it possible for even the non-majors or the beginners to make a specific useful homepage with the simple manipulation of a mouse and the minimal input of necessary information. This system is the customer request-oriented homepage automation system that makes it possible with ease not only to manufacture homepage but also to maintain homepage without direct handling of homepage source.