• Title/Summary/Keyword: 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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    • v.33 no.1_2
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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.

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

  • 김경섭;이정표
    • Journal of the Korea Society for Simulation
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    • v.9 no.2
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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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A New Field/Frame Mode Selection and Buffer Control Strategy for Interlaced Digtal HDTV Image Coding (비월 주사 방식의 디지탈 HDTV 영상 부호화를 위한 새로운 필드/프레임 모드 선택 및 버퍼 제어 기법)

  • 김중곤;송규익;김덕규;김건일
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.8
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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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TOC Buffer Management using the Concept of the Postponement (Postponement 개념을 이용한 TOC 버퍼 관리)

  • 한지은
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2001.10a
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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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Virtual System Buffer Model in Flexible Manufacturing Systems with an AGV System (AGVS를 포함한 FMS에서의 가상 시스템버퍼 모델에 관한 연구)

  • Kyung Sup Kim
    • Journal of the Korea Society for Simulation
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    • v.7 no.2
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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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Adhesion Strength and Interface Chemistry with Cr, 50%Cr-50%Ni or Ni Buffer Layer in Cu/buffer Layer/polyimide System (Cu/buffer layer/polyimide 시스템에서 Cr, 50%Cr-50%Ni 및 Ni 버퍼층에 따른 접착력 및 계면화학)

  • Kim, Myung-Han
    • Korean Journal of Materials Research
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    • v.19 no.3
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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.

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

  • Lee, Byeong-Gil;Byun, Minseok;Kim, Yeojin;Lee, Jonghwan
    • Journal of the Semiconductor & Display Technology
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    • v.19 no.4
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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.

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

  • Kim, Nam-Gi;Park, In-Yong;Jeong, Hye-Yeong;Yun, Hyeon-Su
    • The KIPS Transactions:PartA
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    • v.9A no.3
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    • pp.317-326
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    • 2002
  • The mobile telecommunication system has been growing exponentially after 1990s due to the high population in a city and the growth of mobile user. In this time, the current mobile system mainly concentrates on the voice communication. However, in the next generation, mobile users want to get very diverse services via mobile terminal such as the Internet access, web access, multimedia communication, and etc. For this reason, the next generation system, such as the UMTS system, has to support the packet data service and it will play the major role in the system. In different from the voice service, the packet data service should store packet data in a buffer at base station before it forwards. Consequently, the performance closely related to the buffer management and its operation. However, until now, there are rare study on the buffer behavior and management. In this paper, we will observe the buffer behavior in the UMTS systems by using simulation and analyze the results. For this research, we generate packet data traffics and model the UMTS system for a simulation. Then we analyze the buffer state by a simulation and calculate the buffer overflow probability by mathematical methods.

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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    • 2003.10a
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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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    • v.55 no.3
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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.