• Journal of Korea Multimedia Society
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• v.3 no.6
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• pp.643-651
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• 2000

ATM network technology is generally used for the integration of multimedia services in high-speed Internet. ABR (Available Bit Rate) and UBR (Unspecified Bit Rate) service classes have been developed specifically to support data application. In this paper, through the result of simulation, we analyzed the effect of TCP data transmission performance by using FRR (Fast Retransmission and Recovery) and Nagle's Algorithm on the UBR service, and by adjusting EFCI switch parameter on the ABR service. As a result of our study, performance improvement of TCP over ATM network is observed by adjusting TCP parameters and setting of effective switch parameter.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.144-147
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• 2001

In ATM Network, many algorithms have been proposed for rate-based ABR flow control. The object of these algorithms is to turn around from cell loss and to use the unused bandwidth by ABR Traffic. These Algorithms are applied to control ABR Traffic by EFCI and ER switches. In this paper, we apply these algorithms to the various stale networks and analysis the characteristics of the algorithms and then attempt to show the loss rate of each algorithms. As the result we compare and analysis the efficiency of them.

• Journal of the Korea Society of Computer and Information
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• v.5 no.2
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• pp.98-104
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• 2000

One of the main features of ABR service is the employment of a rate-based flow control mechanism, and congestion control plays an important role in the effective and stable operation of ATM networks Feedback from the network switches to the end system gives users the information necessary to adjust transmission rates appropriately according to the current networks load. Congestion controls by feedback mechanism are classified as EFCI and ER mode. We analyze the performance of EFCI and ER and propose a new ABR traffic control strategy by integrating EFCI and ER modes to improve the traditional traffic control. Through the distributed simulation. the performance improved by the proposed control strategy is analyzed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.4
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• pp.745-750
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• 2000

In ATM Network, many algorithms have been proposed for rate-based ABR flow control. The object of these Algorithms is to turn around from cell loss and to use the unused bandwidth by ABR Traffic. These Algorithms are applied to control ABR Traffic by EFCI and ER switches. In previous paper, we showed the using rate of bandwidth for the characteristic of each algorithm applied these algorithm network. In this paper, we will do that to apply these algorithms to a network and to make a graph of characteristic of each algorithm.

• Journal of Korean Clinical Nursing Research
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• v.14 no.1
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• pp.15-23
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• 2008

Purpose: The purpose of this study was to examine the effect of absolute bed rest(ABR) on occurrence of bleeding, discomfort and back pain after kidney biopsy. Method: This study was the nonequivalent control group posttest design. The experimental group was allowed to stay in beds for 18 hour-bed rest(BR) after 6 hour-ABR while the control group was allowed to stay ABR for 24 hours. Results: No bleeding sign was showed for all the patients. Discomfort of voiding, eating, ABR in the control group appeared at a higher level. Three subjects in the control group needed nelaton catheterization, whereas no catheterization was required in the experimental group. There was no significant difference in back pain. However, the control group used more pain killer with significant difference. From these results. Conclusion: There was no significant correlation between ABR time and bleeding. On the other hand, the discomfort of the experimental group appeared at a lower level by reducing ABR time. Therefore, Reduction of ABR time after kidney biopsy would be more efficient way for patients.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.5
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• pp.973-980
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• 2005

In this paper, we analyze previous flow control algorithm for serving ABR traffic, and then propose the algorithm which calculate fair transmission rate and control efficiently ABR traffic using VS/VD switch which has an effect on PNNI environment with long delay. For getting the transmission rate, the proposed algorithm use FMMRA as ER scheme which calculate exactly the fair share. And, in large delay state, we can obtain fair cell sharing by calculating transmission rates which obtained by transmitted queue length information of VD to VS for serve and drain cell in queue Through the computer simulation, we evaluate the performance of proposed algorithm. According to the results, the proposed algorithm shows good performance.

• The Journal of the Acoustical Society of Korea
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• v.17 no.7
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• pp.82-90
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• 1998

본 논문에서는 신호 채널에 의한 ABR 트래픽 제어 메카니즘을 제시하고, ABR 트 래픽을 제어하기 위한 Bandwidth Request 메시지와 Bandwidth Allocated 메시지를 고안하 였다. 또한 새로운 트래픽 파라메터 협상 메시지 흐름을 고안 하였으며, 성능 분석을 통하여 기존 방식에 비하여 호 처리시간과 가용 대역폭 이용 측면에서 본 논문에서 제안한 방안이 월등히 우수함을 알 수 있었다.

• Review of KIISC
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• v.8 no.1
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• pp.99-112
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• 1998

ATM 방식을 근간으로 한 광대역 통신망의 급속한 발전에 따라 점차로 그 수요가 증가할 데이터 응용들을 위한 ABR서비스는 우선 순위가 높은 다른 서비스들이 이용하고 남는 가용 대역폭을 최대한 활용해야 한다. 따라서 최근까지도 피드백을 이용한 대응적 제어를 이용한 폭주 제어 방식들에 대한 연구가 진행되어왔고 여러 알고리즘들이 제안되었다. 본 논문에서는 ATM망에서의 ABR(Available Bie-Rate) 트래픽의 특성과 ATM포럼과 ITU-T등에서 표준화되었거나 현재 연구중인 다양한 제어 기법들에 대한 개괄적인 분석이 수행되었다. 그와 아울러 각 알고리즘들의 장, 단점을 살펴보고 개선되어야 할 사항들을 제시하였으며 좀 더 효듈적인 제어를 위해 고려되어야 할 트래픽 특성들을 설명하고 있다.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.63-66
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• 2000

본 논문에서는 신호 채널을 이용하여 실제적인 호 연결 처리 전에 착신 단말의 가용 전송률 및 서비스 호환성 여부를 조사하는 Look Ahead Enquiry/Response 기법에 의한 새로운 ABR 트래픽 파라메터 협상 베시지 흐름 메카니즘을 제안하였으며, 신호채널을 이용한 ABR 트래픽 전송률 제어가 가능하도록 Bandwidth Request 메시지와 Bandwidth Allocated 메시지를 고안하였다. 또한 성능 분석을 통하여 기존 방식과 비교하여 호 처리시간과 링크 이용 효율측면에서 본 논문에서 제안한 방안이 월등히 우수함을 알 수 있었다.

• Clinical and Experimental Pediatrics
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• v.45 no.10
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• pp.1199-1203
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• 2002

Purpose : The study aimed to evaluate the efficacy of auditory brainstem response(ABR) as a screening tool in children with speech and language disorders. Methods : Between January 1, 1999 and December 31, 2001, 139 patients with chief complaints of speech and language delay were recruited from the pediatric neurology clinic, Kyungpook National University Hospital, Daegu, Korea. They had ABR on entry and the clinical data were then analyzed. Results : Fifteen out of 139 cases(10.8%) showed abnormal findings; seven had pervasive developmental disorders, four had developmental language disorders, and four were noted to have other conditions. Among them, seven cases were noted to have conductive hearing loss and eight had sensoryneuronal hearing loss. We also evaluated the normal values in children at the ages of 18 months to seven years. The mean latency of wave I and V were $1.40{\pm}0.13$ and $5.57{\pm}0.26$ respectively. Interpeak latency of I-V was $4.18{\pm}0.24$. Conclusion : Based on these findings, ABR has proved to be a highly sensitive and specific index of hearing impairment. It should be used as a screening tool in children with speech and language disorders.