SAN을 이용한 제한된 버퍼 크기를 갖는 출력큐잉 ATM 스위치 성능평가

장경수,신호진,신동렬,Jang, Kyung-Soo,Shin, Ho-Jin,Shin, Dong-Ryeol 한국정보처리학회 2000 정보처리논문지 Vol.7 No.8

High speed switches have been developing to interconnect a large number of nodes. It is important to analyze the switch performance under various conditions to satisfy the requirements. Queueing analysis, in general, has the intrinsic problem of large state space dimension and complex computation. In fact, The petri net is a graphical and mathematical model. It is suitable for various applications, in particular, manufacturing systems. It can deal with parallelism, concurrence, deadlock avoidance, and asynchronism. Currently it has been applied to the performance of computer networks and protocol verifications. This paper presents a framework for modeling and analyzing ATM switch using stochastic activity networks (SANs). In this paper, we provide the ATM switch model using SANs to extend easily and an approximate analysis method to apply A TM switch models, which significantly reduce the complexity of the model solution. Cell arrival process in output-buffered Queueing A TM switch with finite buffer is modeled as Markov Modulated Poisson Process (MMPP), which is able to accurately represent real traffic and capture the characteristics of bursty traffic. We analyze the performance of the switch in terms of cell-loss ratio (CLR), mean Queue length and mean delay time. We show that the SAN model is very useful in A TM switch model in that the gates have the capability of implementing of scheduling algorithm. 네트워크 연결을 위한 고속 스위치는 계속해서 발달하여 왔으며, 스위치가 필요한 성능을 내는가를 여러 조건으로 분석하는 것은 중요한 일이다. 하지만, 복잡한 구조를 가진 시스템을 모델링하여 그 성능을 측정하는 것은 쉬운 일이 아니다. 큐잉이론을 이용한 모델링은 큰 상태 공간을 고려해야 됨은 물론이고 성능평가에 있어서도 복잡한 계산과정을 수행해야 하지만, SAN(Stochastic Activity Networks)에 의한 모델링과 성능평가는 그에 비해 간단하다는 장점이 있다. 본 논문의 목적은 출력포트에 큐를 갖는 고속 ATM 스위치를 확장된 SPN(Stochastic Petri Net)인 SAN을 이용해 모델링하고, 셀 도착 과정은 실제 트래픽과 유사한 특징을 가지고 있는 MMPP(Markov Modulated Poisson Process)로 모델링하여 그 성능을 평가하는데 있다. MMPP 모델을 이용한 버스티 트래픽을 고겨한 성능측정과 아울러 SAN의 장점을 이용한 확장이 용이한 스위치 모델을 보이고자 한다. 제한된 버퍼 크기를 갖는 출력 큐잉 ATM 스위치에 도착하은 셀은 포아송 도착 과정에서는 정확히 표현할 수 없는 버스티 특징을 표현할 수 있어 좀더 실제 트래픽에 가까운 MMPP로 모델링한다. SAN 모델은 UltraSAN 소프트웨어 패키지를 이용해 대기행렬의크기, 지연시간 그리고 셀 손실률에 대한 성능을 측정한다.

Newcastle Disease Virus의 Fusion 단백 유전자의 제한효소분절형태(RELP)의 특이성

장경수,김지영,김석,김태용,송영환,허지연,김현수,송희종,전무형 충남대학교 수의과대학 동물의과학연구소 2001 動物醫科學硏究誌 Vol.9 No.-

To evaluate the specificity of restriction fragment length polymorphism (RFLP) of Newcastle disease virus (NDV) fusion (F) protein gene for various NDV strains. F protein genes of NDV CBP-1 isolate, LaSota, B1 and Kyojungwon (KJW) were amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) and RFLP were examined. In RT-PCR using F primer sets for 1.7 kb F gene, the amplified products were observed in CBP-1, LaSota and B1 except KJW. However, F2 primer set for 521 bp yielded the amplified bands with all strains. The amplified F genes (1.7 kbp) were treatd with 15 different restriction enzymes to analyze RFLP and the cleavage patterns. CBP-1 showed various cleavage patterns with 8 enzymes, LaSota, with 11 enzymes and B1, with 11 enzymes. According to the cleavage patterns, the physical maps were constructed, and it was found that CBP-1, LaSota and B1 strains had specific cleavage sites with HinfI, XbaI and XhoI. These findings suggest that RFLP are worth applying in the diagnosis and molecular epidemiological studies of Newcastle disease.

의치상 이장재 표면의 캔디다 균주에 대한 항균제의 억제 효과

장경수,Jang, Kyung-Soo 대한치과보철학회 1999 대한치과보철학회지 Vol.37 No.3

The purpose of this study was to evaluate the in vitro antifungal effect of several kinds of denture lining materials containing nystatin and silver-zeolite on Candida albicans. Three commercially available tissue conditioners (Soft-Liner, Coe-Comfort, Coe-Soft) and two direct denture relining materials (Tokuso Rebase, Durabase) were selected. In terms of the zone of inhibition and some basic physical properties, I could find the following results ; 1. Nystatin or silver-zeolite included in those relining materials had definite antifungal activities against the Candida albicans. 2. As times went on, both of the antifungal agents's activities decreased gradually. 3. Antifungal agents did not affect the relining materials' basic physical properties. 4 Direct chairside relining materials showed unfavorable dark discoloration with response to silver-zeolite.

인상재-그 특성과 사용법

장경수,최기열,윤숙진 대한치과의사협회 1998 대한치과의사협회지 Vol.36 No.11

ICCP를 사용한 전력센터간의 통신 프로토콜 구현

장경수,장병욱,한경덕,신동렬,Jang, Kyung-Soo,Chang, Byung-Wook,Hahn, Kyung-Duk,Shin, Dong-Ryeol 한국정보처리학회 2000 정보처리논문지 Vol.7 No.12

현재의 전력시스템은 컴퓨터와 통신기술의 발전으로 분산시스템인 EMS(Energy Menagement System)/SCADA(Super-vision Control and Data Acquisition) 형태로 운영되어 전력의 생산, 전송 그리고 분배가 효과적으로 이루어지고 있다. 그러나 각 시스템은 언어, 운영체제 그리고, 통신프로토콜이 서로 다른 제품으로 구성되어 시스템간에 데이터를 교환하는데 많은 어려움이 따르고 있다. 이러한 문제를 해결하기 위해서는 미국 전력연구소는 전력제어센터간의 통신을 담당하는 ICCP(Inter-Control Center Protocol)라는 새로운 형태의 통신규약을 발표하였다. ICCP는 자동화용 표준 통신규약인 MMS(Manufacturing Message Specification)를 응용계층의 하부 규약으로 지정함으로써 서로 다른 기종의 제어센터간의 원활한 통신을 지원한다. 본 논문은 ICCP의 특징과 MMS와 ICCP가 어떻게 상호 연관되는가를 밝힌다. ICCP에서 이용하는 MMS 라이브러리(library)의 86개의 서비스 중 일부 서비스를 구현한 후 이것을 이용하여 TCP/IP 환경 하에서 ICCP의 기본이면서 핵심적인 기능을 구현한다. 그 다음, ICCP 프로토콜을 이용하여 EMS간의 통신을 모델링하고, 전력센터간의 실제 데이터 교환을 윈도우 환경 하에서 구현하여 ICCP 프로토콜의 동작과 기능을 보여준다. Current power systems are distributed geographically and operated in the form of Energy Management System(EMS)/ Supervision Control and Data Acquisition(SCADA) with the aid of computers and communications. Recently a variety of utilities have had interests in using inforrration technology to bring the efficiency and low operational costs. There is also a trend to integrdte the production, transmission, distribution and management/control of power into one and unified distributed system. To this end, Electric Power Hesearch Institute(EPRI) announced a new standard communication protocol called Inter-Control Center Protocol(ICCP).ICCP specifies the use of Manufacturing Message Specification(MMS) for services required by rccr in application layer and supports the communications between heterogeneous control centers. This paper presents the characteristics of MMS,ICCP and their relationship. Futherrnore, we implement the basic functional blocks of ICCP using MMS services under TCI/IP environments. Finally, we model a simple power system and apply the rccp protocol to this system in a window-based scheme, and finally show the operation and validation of this protocol.

치과 임플랜트 보철 장착자의 구강 감각 기능에 관한 연구

장경수,김영수,Jang, Kyoung-Soo,Kim, Yung-Soo 대한치과보철학회 1991 대한치과보철학회지 Vol.29 No.1

In this study, oral sensory function in the osseointegrated root form implant-supported prostheses wearers was estimated by measuring occlusal tactile perception threshold of thickness and sensibility threshold against lateral static loading, and comparing with normal dentition subjects and complete denture wearers group. Osseointegrated root form implants seemed to be restored in the sensation to some extent, and so, dental implants restored edentulous patients in a wide meaning. Conclusions were summarized as following. 1. Occlusal tactile perception threshold of thickness was highest in complete denture wearers group, following by implant-supported prostheses wearers group, normal dentition subjects group. 2. In the implant-supported prostheses wearers group, occlusal tactile perception threshold of opposing artificial teeth case was higher than of opposing natural or opposing implantsupported teeth case. 3. Sensibility threshold against lateral loading of complete denture wearers and implantsupported prostheses wearers group was higher than that of normal dentition subject group. 4. In the implant-supported prostheses group, sensibility threshold against lateral loading was not significantly different between upper and lower jaws. 5. In occlusal tactile perception threshold of thickness and sensibility threshold against lateral loading test, there was no regularity among values of each tooth, and no significant difference between anterior and posterior teeth as well.

대구약령시축제의 서비스품질 평가 - 중요도/성취도 분석을 중심으로 -

장경수 한국이벤트학회 2006 이벤트학연구 Vol.5 No.2

스포츠 이벤트의 서비스품질이 참가자 만족과 행동의도에 미치는 영향

장경수 한국경영교육학회 2008 한국경영교육학회 학술발표대회논문집 Vol.2008 No.6

협동조합의 조합원 가치와 거버넌스에 관한 고찰

장경수 한국협동조합학회 2006 韓國協同組合硏究 Vol.24 No.1

The purpose of this paper is to analyze theoretically the weakness of corporate governance of cooperatives and to propose strategies for strengthening governance. The objective of cooperatives cited in agricultural cooperative law could motivate the inefficiency of cooperative management. Some characteristics of cooperatives such as one member-one vote rule and owner = customer relationship may become sources of the weakness of corporate governance. The multi-business system with non-profit principle produces the agency problem of managers of non-financial business divisions. Strategies for improving corporate governance should be based on the objective redefined as the maximization of membership value. Including non-member stakeholders in the governance of cooperatives improves internal governance because of their higher incentive to monitor management. For preventing the agency problem of managers in non-financial business divisions, the evaluation and disclosure of performance compared with competing firms within their industries should be required. Risk-based rules for deposit insurance and capital adequacy enhance soundness of cooperative management. And the national federation`s role as external governance is crucial to make up for the lack of market discipline.

지역은행으로서의 농협의 성격과 경쟁력 기초

장경수 농협대학교 협동조합경영연구소 1997 협동조합경영연구 Vol.20 No.-