• 한국통신학회논문지
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• 제28권5B호
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• pp.388-403
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• 2003

유선 네트워크 환경에서 실시간 응용의 QoS 보장을 위한 자원 예약 프로토콜로서 RSVP가 발표된 바 있다. 한편, 무선 네트워크 환경에서의 응용 서비스가 대중화되면서 이동 컴퓨팅 환경에서의 QoS 보장이 이슈가 되고 있다. 이에 따라 RSVP와 이동 컴퓨팅 환경에서 이동성을 지원하는 Mobile IP간의 연동이 활기를 띠고 있다. 본 논문에서는 이동 컴퓨팅 환경에서 통합 이동성을 지원하는 QoS 보장형 자원 예약 프로토콜인 I-MRSVP(Integrated-Mobile RSVP)를 제안한다. I-MRSVP 프로토콜은 Mobile IP 기반의 광역 셀과 Cellular IP 기반의 협역 셀간의 상호운용성을 제공하는 통합 이동성을 지원하고 신호 세기 기반 예측 자원 예약 기법을 통해 효율적인 자원 예약 기능을 제공한다.

• 한국통신학회논문지
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• 제12권2호
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• pp.160-167
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• 1987

데이터와 音聲 共用의 近距離 通信網에서 메시지의 種類와 局의 位置에 따라 優先權을 , 局의 數에 관계없이 단지 2비트만으로 傳送豫的 可能한 CS/MLBP(carrier sense/message and location based proiority)豫的制御方式을 提案하였다. 提案된 方式에서는 局數에 관계없이 예약비트가 단지 2비트이므로 예약시간이 짧아 網의 delay-throughtput特性이 좋아지고, 高負荷에서 音聲패킷의 棄却率도 적을 뿐만 아니라 局數의 增加가 delay-throughput特性에 影響을 주지 않는 長點이 있다. 시뮬레이션을 토하여 本 方式의 傳送性能을 評價하고 DSMA(distributed schedulign multiple access)를 利用한 方式$^(6)$과 비교하였다.

• 한국중재학회지:중재연구
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• 제22권1호
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• pp.43-63
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• 2012

Media ADR is currently emerging as one of successful cases in South Korea while environmental ADR was known not to satisfy both defendants and offenders. Thus, this paper is intended to present proper remedies for typical compensation schemes of environmental ADR by comparing the two ADRs regarding legal reservation of compensation clause. It was found that the media ADR helped clients achieve a more fast and easy dispute resolution by providing compensation standards based on various categories such as types and scopes of compensation. However, the compensation scheme of environmental ADR brought out public complaints and inadequate services due to inconsistency and instability in terms of legal reservation. The results indicate that the compensation clause based on the reservation of laws in media ADR could be used not only as a checklist to confirm limitations of environmental ADR, but also as realistic evidences to adjust the compensation standard systematically that is under development and requires remodelling. As a result, the research findings have opened the new possibilities of "the quality assurance of environmental ADR based on the domestic legislation", proposed as an initial aim of this paper.

• 산업경영시스템학회지
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• 제37권1호
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• pp.50-59
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• 2014

In this paper, we develop an efficient approach to solve a multiple-item budget-constraint newsboy problem with a reservation policy. A conventional approach for solving such problem utilizes an approximation for the evaluation of an inverse of a Gaussian cumulative density function when the argument of the function is small, and a heuristic method for finding an optimal Lagrangian multiplier. In contrast to the conventional approach, this paper proposes more accurate method of evaluating the function by using the normalization and an effective numerical integration method. We also propose an efficient way to find an optimal Lagrangian multiplier by proving that the equation for the budget-constraint is in fact a monotonically increasing function in the Lagrangian multiplier. Numerical examples are tested to show the performance of the proposed approach with emphases on the behaviors of the inverse of a Gaussian cumulative density function and the Lagrangian multiplier. By using sensitivity analysis of different budget constraints, we show that the reservation policy indeed provides greater expected profit than the classical model of not having the reservation policy.

• Industrial Engineering and Management Systems
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• 제8권2호
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• pp.72-79
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• 2009

The ultimate goal of inventory management is to decide the timing and the quantity of ordering in response to uncertain demands. Recently, some researchers have focused upon an impact of distortions in the information, e.g., customer order cancellation, on an economical inventory policy. The customer order cancellation is considered a kind of distortions in demands, because a demand that is eventually cancelled is equivalent to a phony demand. Also, there are some additional distortions in the inventory information. For instance, the procurement of suppliers may include some nonconforming items as a result of imperfect production and inspection by the suppliers, and/or damage in transit. The nonconforming item should be considered a kind of distortions in the inventory information, because the nonconforming item is equivalent to a phony stock. In this article, we consider an inventory model under the situation that customers can cancel their orders and the procurement of suppliers may include some nonconforming items. Then, we introduce the customer order reservation into the inventory model for the purpose of avoiding the costly backlogs, because the customer order reservation gives retailers a period to fulfill customer's requests. We formulate a periodic review (s, S) inventory model and investigate the economical operation under the situation mentioned above. Further, through the sensitivity analysis, we show the impact of these distortions and the effect of the customer order reservation on the inventory policy.

• 한국정보통신학회논문지
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• 제7권7호
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• pp.1427-1433
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• 2003

본 논문은 TDM 방식을 적용한 회선 교환 방식의 WDM 네트워크에서 라우팅, 파장 할당 및 시간슬롯할당의 문제로서, 동적으로 광 경로를 설정하기 위한 분산 제어 프로토콜을 제안하였다. 제안한 분산 제어 프로토콜에서는 블록킹 확률을 줄일 수 있도록 후방 예약 방식을 사용하였다. 예약 실패를 최소화하기 위해 여러 채널을 예약하는 진취적 예약 방법과 단지 하나의 채널을 예약하는 보수적 예약 방법을 적용하여 두개의 방법을 시뮬레이션을 통해 비교하였다. 제안한 분산 프로토콜을 성능 평가하여 WDM/TDM 방식이 WDM 방식보다 성능이 우수함을 보이고 진취적 예약 방법이 적절한 채널 수를 사용할 경우 보수적 예약 방법보다 블록킹 확률을 줄일 수 있음을 보인다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.79-82
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• 1998

This paper proposes the MAC scheme based on variable reservation slots for the guaranteed QoS of ATM services on RF and evaluates the performance. This scheme has improved the utilization of channel and success ratio of reservation by using the variable number of RES(REServation) slots according to the collisions. It is the results of performance evaluation that the CTD of CBR Service is 7.9ms with overall $load(\rho)$ 85%. And also VBR service of it is 3.5ms, ABR service of it is 9.8ms with overall load 85%.

• 제어로봇시스템학회논문지
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• 제11권9호
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• pp.816-821
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• 2005

The remote operation of $4\~5$ cranes for container loading/unloading at a port by one operator will dramatically improve loading/unloading efficiency through productivity increase, cost reduction, and so on. This study develops a remote crane control system for container loading/unloading yard cranes. First, a wireless video and audio system to transmit views and sounds of the working field is designed by using 3 web cameras and a microphone. Next, a RSVP-based multi-path reservation method is presented with a view to improving the quality of service in the communication network for remote control. Simulation results show that a RSVP-based multi-path reservation can enhance the reservation success rate in the TCP/IP network.

• ETRI Journal
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• 제35권1호
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• pp.58-68
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• 2013

Five-phase reservation protocol (FPRP) is a contention-based media access control protocol for wireless ad hoc networks. FPRP uses a five-phase reservation process to establish slot assignments based on time division multiple access. It allows a node to reserve only one slot in an information frame. Once a node has reserved a slot, it will cease contending for other slots. As a result, there may be less contending nodes in the remaining slots, so the time slots in an information frame are not fully used by FPRP. To improve time slot utilization, this paper proposes an improved pseudo-Bayesian algorithm, based on which an improved contention access mechanism for FPRP is proposed, in which nodes are allowed to contend for more than one slot in a reservation frame according to a certain probability/priority. Simulation results indicate that the proposed mechanism performs better than FPRP in time slot utilization and hence the network throughput under various scenarios.

• 대한전자공학회논문지TC
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• 제40권10호
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• pp.43-50
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• 2003

본 논문에서는 OBS 네트워크를 위한 광 자원 예약 프로토콜 (Optical Resource Reservation Protocol) 을 제안하였다. OBS 네트워크 상에서 광 자원 예약 프로토콜을 사용하면 입구 OBS 노드와 출구 OBS 노드 사이의 이용 가능한 광 자원을 측정하여 예약할 수 있고, 입구 OBS 노드에서는 예약된 파장 조각의 크기에 따라 버스트 전송 시간과 버스트 크기를 설정하여 보냄으로써 OBS 네트워크에서의 블록 킹 문제를 해결할 수 있을 뿐만 아니라, 광 채널 이용률을 최대 두 배 가까이 증가시킬 수 있다. 본 논문에서는 NS2 시뮬레이터를 이용하여 제안된 광 자원 예약 프로토콜의 성능을 분석하였다.