• 제목/요약/키워드: buffer system

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DISCRETE-TIME BUFFER SYSTEMS WITH SESSION-BASED ARRIVALS AND MARKOVIAN OUTPUT INTERRUPTIONS

  • Kim, Jeongsim
    • Journal of applied mathematics & informatics
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    • 제33권1_2호
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    • pp.185-191
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    • 2015
  • This paper considers a discrete-time buffer system with session-based arrivals, an infinite storage capacity and one unreliable output line. There are multiple different types of sessions and the output line is governed by a finite state Markov chain. Based on a generating functions approach, we obtain an exact expression for the mean buffer content.

Deadlock과 Workload에 따른 FMS의 버퍼 Capacity 결정에 관한 연구 (A Study of Buffer Allocation in FMS based on Deadlock and Workload)

  • 김경섭;이정표
    • 한국시뮬레이션학회논문지
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    • 제9권2호
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    • pp.63-73
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    • 2000
  • Due to the complexity of part flow and limited resources, FMS(Flexible Manufacturing System) develops blocking, starvation and deadlock problems, which reduce its performance. In order to minimize such problems buffers are imposed between workstations of the manufacturing lines. In this paper, we are concerned with finding the optimal buffer allocation with regard to maximizing system throughput in limited total buffer capacity situation of FMS. A dynamic programming algorithm to solve the buffer allocation problem is proposed. Computer simulation using Arena is experimented to show the validation of the proposed algorithm.

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비월 주사 방식의 디지탈 HDTV 영상 부호화를 위한 새로운 필드/프레임 모드 선택 및 버퍼 제어 기법 (A New Field/Frame Mode Selection and Buffer Control Strategy for Interlaced Digtal HDTV Image Coding)

  • 김중곤;송규익;김덕규;김건일
    • 전자공학회논문지B
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    • 제31B권8호
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    • pp.109-118
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    • 1994
  • We proposed new field/frame mode selection quantization and buffer control strategy for interlaced digital HDTV image coding system. The field/frame mode selection is performed based on the mean square error and number of generated bits for each superblock. The quantization factor for each superblock is determined by the characteristics of human visual system and buffer status. The statistical characteristics of the number of generated bits for basis block and the prediction of buffer status are used for buffer control. Simulation results show that the proposed field/frame mode selection and rate buffer control. Simulation results show that the proposed field/frame mode selection and rate buffer control strategy have good subjective image quality and have stable buffer status.

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Postponement 개념을 이용한 TOC 버퍼 관리 (TOC Buffer Management using the Concept of the Postponement)

  • 한지은
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2001년도 추계학술대회 논문집
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    • pp.275-278
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    • 2001
  • TOC(Theory of Constraints) - the emphasis of this philosophy was on identifying and eliminating constraints(bottle-necks) in the system. TOC solves this and optimizes whole system by improving manufacturing constraints that limit system result. In this paper, it is shown that the concept of the "delayed differentiation" can be applied for enhancing the efficiency of the time buffer and thus reducing the of the time buffer.

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AGVS를 포함한 FMS에서의 가상 시스템버퍼 모델에 관한 연구 (Virtual System Buffer Model in Flexible Manufacturing Systems with an AGV System)

  • Kyung Sup Kim
    • 한국시뮬레이션학회논문지
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    • 제7권2호
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    • pp.45-62
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    • 1998
  • This research is concerned with buffer management in a multi-cell FMS with an AGVS. Buffers in manufacturing systems are required to reduce blocking and starving caused by breakdowns, variability in process times, and diversity of part routing. Due to the high per unit buffer cost, which primarily consists of floor space and equipment costs, the total capacity of buffers in and FMS is very limited. Proper buffer management can provide a high system efficiency. This paper presents a buffer management model for a multi-cell FMS with an AGVS and a simulation study to compare the proposed model to a conventional buffer management model in a job shop FMS.

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Cu/buffer layer/polyimide 시스템에서 Cr, 50%Cr-50%Ni 및 Ni 버퍼층에 따른 접착력 및 계면화학 (Adhesion Strength and Interface Chemistry with Cr, 50%Cr-50%Ni or Ni Buffer Layer in Cu/buffer Layer/polyimide System)

  • 김명한
    • 한국재료학회지
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    • 제19권3호
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    • pp.119-124
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    • 2009
  • In the microelectronics packaging industry, the adhesion strength between Cu and polyimide and the thermal stability are very important factors, as they influence the performance and reliability of the device. The three different buffer layers of Cr, 50%Cr-50%Ni, and Ni were adopted in a Cu/buffer layer/polyimide system and compared in terms of their adhesion strength and thermal stability at a temperature of $300^{\circ}C$ for 24hrs. A 90-degree peel test and XPS analysis revealed that both the peel strength and thermal stability decreased in the order of the Cr, 50%Cr-50%Ni and Ni buffer layer. The XPS analysis revealed that Cu can diffuse through the thin Ni buffer layer ($200{\AA}$), resulting in a decrease in the adhesion strength when the Cu/buffer layer/polyimide multilayer is heat-treated at a temperature of $300^{\circ}C$ for 24hrs. In contrast, Cu did not diffuse through the Cr buffer layer under the same heat-treatment conditions.

하모니서치 알고리즘을 이용한 반도체 공정의 최적버퍼 크기 결정 (Determination of Optimal Buffer Size for Semiconductor Production System using Harmony Search Algorithm)

  • 이병길;변민석;김여진;이종환
    • 반도체디스플레이기술학회지
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    • 제19권4호
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    • pp.39-45
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    • 2020
  • In the production process, the buffer acts as a buffer to alleviate some of the problems such as delays in delivery and process control failures in unexpected situations. Determining the optimal buffer size can contribute to system performance, such as increased output and resource utilization. However, there are difficulties in allocating the optimal buffer due to the complexity of the process or the increase in the number of variables. Therefore, the purpose of this research is proposing an optimal buffer allocation that maximizes throughput. First step is to design the production process to carry out the research. The second step is to maximize the throughput through the harmony search algorithm and to find the buffer capacity that minimizes the lead time. To verify the efficiency, comparing the ratio of the total increase in throughput to the total increase in buffer capacity.

UMTS 시스템에서 기지국 버퍼에 대한 실험 및 분석 (Simulation and Analysis of Base Station Buffer in UMTS Systems)

  • 김남기;박인용;정혜영;윤현수
    • 정보처리학회논문지A
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    • 제9A권3호
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    • pp.317-326
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    • 2002
  • 도시 인구 집중과 이동 인구의 증가로 이동 통신 시스템은 90년대 이후 급격한 발전을 하고 있다. 그러나 현재 널리 사용되고 있는 2세대 이동 통신 시스템은 음성에만 치중하여 개발되었고 시장이 거의 포화상태에 이르렀다. 따라서 앞으로 다가올 UMTS와 같은 제 3세대 이동 통신 시스템에서는 무선 인터넷과 같은 본격적인 데이타 서비스를 위해 패킷 데이타 통신이 매우 중요한 부분으로 떠오르고 있다. 음성 서비스와는 달리 패킷 데이타 특성에 갖는 패킷 데이타 서비스를 제공하기 위해서 UMTS 시스템에서는 전송하기 전에 반드시 데이타를 버퍼에 저장해야 한다. 하지만 지금까지 패킷 데이타 서비스를 위한 버퍼가 어떻게 얼만큼 필요하고 트래픽에 따라 그 상태가 어떻게 변화하는지에 관한 연구는 거의 진행되어 있지 않다. 본 논문에서는 UMTS 시스템에서 BS (Base Station)에 놓이는 버퍼 상태가 어떻게 변화하는지 알아 보기 위해 버퍼 상태 분석을 위한 UMTS 시스템 모델을 구성하고 실험을 통해 그 결과를 관찰 분석한다. 그리고 버퍼 상태를 확률을 통해 수식적으로도 분석한다.

Development of a Frame Buffer Driver for Embedded Linux Graphic System

  • Kim, Ga-Gue;Kang, Woo-Chul;Jung, Young-Jun;Lee, Hyung-Seok
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2116-2120
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    • 2003
  • A frame buffer device is an abstraction for the graphic hardware. It allows application software to access the graphic hardware through a well-defined interface, so that the software doesn’t need to know anything about the low-level interface stuff. We develop a frame buffer driver for VIA’s CLE266 graphic system based on ‘Qplus’, an embedded linux operating system developed by ETRI. Then, it will be seen that our frame buffer system is applied to embedded solutions such as movie player and X server successfully.

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Investigation of the various properties of several candidate additives as buffer materials

  • Gi-Jun Lee;Seok Yoon;Taehyun Kim;Seeun Chang
    • Nuclear Engineering and Technology
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    • 제55권3호
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    • pp.1191-1198
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    • 2023
  • Bentonite buffer material is a critical component in an engineered barrier system (EBS) for disposing high-level radioactive waste (HLW). The bentonite buffer material protects the disposal canister from groundwater penetration and releases decay heat to the surrounding rock mass; thus, it should possess high thermal conductivity, low hydraulic conductivity, and moderate swelling pressure to safely dispose the HLWs. Bentonite clay is a suitable buffer material because it satisfies the safety criteria. Several additives have been suggested as mixtures with bentonite to increase the thermal-hydraulic-mechanical-chemical (THMC) properties of bentonite buffer materials. Therefore, this study investigated the geotechnical, mineralogical, and THMC properties of several candidate additives such as sand, graphite, granite, and SiC powders. Datasets obtained in this study can be used to select adequate additives to improve the THMC properties of the buffer material.