• Title/Summary/Keyword: buffer time

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A Simulation-based Heuristic Algorithm for Determining a Periodic Order Policy at the Supply Chain: A Service Measure Perspective (공급사슬 내의 재고관리를 위한 모의실험에 기초한 발견적 기법: 봉사척도 관점)

  • Park, Chang-Kyu
    • IE interfaces
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    • v.13 no.3
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    • pp.424-430
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    • 2000
  • Supply chain management (SCM) is an area that has recently received a great deal of attention in the business community. While SCM is relatively new, the idea of coordinated planning is not. During the last decades, many researchers have investigated multi-stage inventory problems. However, only a few papers address the problem of cost-optimal coordination of multi-stage inventory control with respect to service measures. Even published approaches have a shortcoming in dealing with a delivery lead time consisted of a shipping time and a waiting time. Assumed that there is no waiting time, or that the delivery lead time is implicitly compounded of a shipping time and a waiting time, the problem is often simplified into a multi-stage buffer allocation and a single-stage stochastic buffer sizing problem at all installations. This paper presents a simulation-based heuristic algorithm and a comparison with others for the problem that cannot be decomposed into a multi-stage buffer allocation and a single-stage stochastic buffer sizing problem because the waiting time ties together all stages. The comparison shows that the simulation-based heuristic algorithm performs better than other approaches in saving average inventory cost for both Poisson and Normal demands.

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Fast NAND Flash Memory System for Instruction Code Execution

  • Jung, Bo-Sung;Kim, Cheong-Ghil;Lee, Jung-Hoon
    • ETRI Journal
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    • v.34 no.5
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    • pp.787-790
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    • 2012
  • The objective of this research is to design a high-performance NAND flash memory system containing a buffer system. The proposed instruction buffer in the NAND flash memory consists of two parts, that is, a fully associative temporal buffer for temporal locality and a fully associative spatial buffer for spatial locality. A spatial buffer with a large fetching size turns out to be effective for serial instructions, and a temporal buffer with a small fetching size is devised for branch instructions. Simulation shows that the average memory access time of the proposed system is better than that of other buffer systems with four times more space. The average miss ratio is improved by about 70% compared with that of other buffer systems.

Improved Real-time Video Conferencing System with Memory Buffer Control Management (메모리 버퍼 제어 관리 기능을 갖춘 향상된 실시간 영상회의 시스템)

  • Yoo, Woo Jong;Kim, Sang Hyong
    • KIPS Transactions on Computer and Communication Systems
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    • v.6 no.6
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    • pp.255-260
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    • 2017
  • The limitation of real-time video conferencing system is that the delay of network and buffering and the transmission of user information are not efficiently performed between systems, so real - time performance is not guaranteed completely. In order to overcome this problem, the study on the extension of the network infrastructure and the jitter delay is actively carried out, but the study on the buffering delay is insufficient. In this paper, we propose a frame-rate control buffer management (FRCB) scheme to solve the problem caused by buffering delay. The FRCB is used to prevent overflow and underflow of the buffer by adopting the two-stage buffer threshold of Fast-play THreshold (FTH) and Slow-play THreshold (STH). Therefore, it showed better performance than jitter buffer even under high CPU load, and showed that it is suitable for high quality real time video conferencing.

Pharmaceutical Study on Clonixin Argininate (Clonixin Argininate의 약제학적 연구)

  • Jee, Ung-Kil;La, Sung-Bum
    • Journal of Pharmaceutical Investigation
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    • v.16 no.2
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    • pp.43-54
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    • 1986
  • To increase the bioavailability of clonixin, clonixin argininate was prepared and compared with clonixin by determining solubility, pKa, lipid-water partition coefficient, dissolution rate and in vivo tests. The results are summerized as followings; 1) The solubility of clonixin argininate was increased by 20 times in water, about 1.2 times in pH 1.2 and pH 8.0 buffer solution, and about 1.8 times in pH 6.8 buffer solution compared with that of clonixin. 2) pKa values of clonixin, clonixin lysinate and clonixin argininate were 6.32, 7.20 and 7.45, respectively. 3) The lipid-water partition coefficient of clonixin argininate was increased more than that of the clonixin in n-hexane, carbon tetrachloride, chloroform, methylene chloride, and n-butanol, but the partition coefficient of clonixin was increased more than that of clonixin argininate in benzene/pH 1.2 buffer solution, ether/pH 8.0 buffer solution, and 3-methylbutyl acetate/pH 1.2, pH 8.0 buffer solution. 4) The time required to dissolve 60% $(T_{60%},\;min.)$ of clonixin argininate was about 1.5 min. in water and pH 1.2 buffer solution, and about 5 min. in pH 6.8 buffer solution. $T_{60%}$ of clonixin lysinate was about 1.5 min. in water, about 1.8 min. in pH 6.8 buffer solution, and about 8 min. in pH 1.2 buffer solution. But $T_{60%}$ of clonixin was about 96 min. in pH 6.8 buffer solution, over 2 hours in water and pH 1.2 buffer solution. 5) Anti-inflammatory effect of clonixin argininate was increased more than that of clonixin over 6 hours, and that of clonixin lysinate was followed by lapse of time. 6) Analgesic effect of clonixin argininate was increased by 1.5 times more than that of clonixin and the effect of clonixin argininate was nearly identical with that of clonixin lysinate. 7) The absorption rates (Ka) of clonixin, clonixin lysinate and clonixin argininate were $0.169\;hr^{-1},\;0.652\;hr^{-1}$ and $0.723\;hr^{-1}$ in situ, respectively.

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Separation Characteristics of Oligodeoxynucleotides by High-Performance Membrane Chromatography (고성능 막 크로마토그래피에 의한 Oligodeoxynucleotides의 분리특성)

  • Kim, Jung-Il;Hong, Seung-Bum;Sun, Hyang;Row, Kyung-Ho
    • KSBB Journal
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    • v.15 no.6
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    • pp.605-608
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    • 2000
  • Oligodeoxynucleotides (ODNs) were separated by high-performance membrane chromatography (HPMC), a combined system of chromatography and membrane. The separation mechanism involved anion-exchange, and the stationary phase was cation CIM (Convective Interaction Media) DEAE disk (16${\times}$3 mm). Two types of mobile phase were used, buffer A (20mM Tris-HCl, pH 7.4) and buffer B (buffer A + 1M NaCl). As the amount of NaCl dissolved in buffer linearly increased, the retention time shortened, which enabled a gradient elution mode. Based on the number of theoretical plates and resolution observed, the optimum mobile phase and operating condition (Buffer A/Buffer B=50/50 - 20/80 vol%, gradient time 2 min) were experimentally determined. In this experimental condition, ODNs were separated within 2 min at a mobile phase flow rate of 6 ml/min.

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Design and Implementation of Large Capacity Cable Checking System using an I/O Buffer Method (입.출력 버퍼방식을 이용한 대용량 케이블 점검 시스템 설계 및 구현)

  • 양종원
    • Journal of the Korea Institute of Military Science and Technology
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    • v.5 no.2
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    • pp.103-115
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    • 2002
  • This paper describes the results on the design and implementation of large capacity cable checking system using I/O buffer method. The I/O buffer module which has feedback loops with input and output buffers is designed with logic gate in the VME board and controlled by MPC860 microprocessor. So this system can check a lot of cable at the same time with less size and less processing time than that of relay matrix method with the A/D converter. The size of the I/O buffer module can be variable according to the number of cable. And any type of cable can be checked even if the pin assignment of cable is changed.

Real-time data transmission through congestion control based on optimal AQM in high-speed network environment (고속 네트워크 환경에서 최적AQM기반의 혼잡제어를 통한 실시간 데이터 전송)

  • Hwang, Seong-Kyu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.7
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    • pp.923-929
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    • 2021
  • TCP communication and packet communication require transmission control technology to ensure high quality and high reliability. However, in the case of real-time data transmission, an inefficient transmission problem occurs. In order to overcome this problem and transmit the packet reliability, in general, early congestion control using the buffer level as an index was used. Control of the congestion control point and the cancellation point is delayed because the point at which congestion is controlled is based on the buffer level. Therefore, in this paper, not only the buffer level indicator, but also the ideal buffer level, which determines the packet discard probability, is classified so that the transmission rate and buffer level that measure network congestion are close to the level above the optimal setting. As a result, it was shown that the average buffer level can be directly controlled by maintaining the average buffer level by the ideal buffer level set in the experiment to prove the proposed method.

Evaluation of the Reliability of Salivary Testing Instrument (타액검사기의 신뢰도 평가)

  • Han, Keumah;Lee, Joonhaeng
    • Journal of the korean academy of Pediatric Dentistry
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    • v.45 no.3
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    • pp.363-369
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    • 2018
  • A salivary testing instrument has an advantage that the method is simple and can be performed in a short time. However, it is necessary to verify the factors that affect the reliability of the result, because the device is easy to use and even saliva collection is simple. The aim of this study was to compare the difference of the test results according to the measurement time in order to analyze the time factor of the external variable among the factors that may affect the measurement results of the salivary testing instrument. The relationship between the measured values of the salivary testing instrument to identify the internal variables was analyzed. Saliva was collected from 20 randomly selected patients regardless of age, sex, or diseases. The mean age was 46.6 years, 10 males and 10 females. The saliva collected was directly measured with the salivary testing instrument as group I. The saliva samples were placed in air in a paper cup for 10 minutes, and then measured as group III. Then group I was remeasured after 30 minutes and assigned as group II. Group III was remeasured after 30 minutes and called as group IV. As a result, all of the cariogenic bacteria, acidity, buffer capacity, blood, leukocyte, protein and ammonia, except buffer capacity, showed statistically significant changes in group II and IV. This means that the reliability of the test results is poor if the measurement time is not observed. Cariogenic bacteria were correlated with leukocyte and protein, buffer capacity was related to acidity, protein, and protein was related to buffer capacity and leukocyte. In conclusion, the result according to the measurement time as the external variable was different, which means that time must be strictly monitored when testing saliva. It is also necessary to take into account the relevance of the correlations between the internal variables and the clinical data.

Minimizing method of initial time for ECC DRAM (ECC를 적용한 DRAM의 초기화 시간 최소화 방법)

  • Roh, Jong-Sung;Kim, Jong-Tae
    • Proceedings of the KIEE Conference
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    • 2006.10c
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    • pp.446-448
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    • 2006
  • DRAM with ECC is used widely and the size of DRAW increases. According to this, DRAM initial time, especially the time to make the whole area typical value, 0, increases. This paper introduces the method that without any additional hardware, using characteristic of DRAM and DRAM controller, minimize that memory initial time. Conservative reordering - it eliminates DRAM read time and makes write buffer used - reduces initial time to make the whole DRAM area 0, by 95.36% for DDR DRAM. 9341% for Rambus DRAM.

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Implementation of a Shared Buffer ATM Switch Embedded Scalable Pipelined Buffer Memory (가변형 파이프라인방식 메모리를 내장한 공유버퍼 ATM 스위치의 구현)

  • 정갑중
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.5
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    • pp.703-717
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    • 2002
  • This paper illustrates the implementation of a scalable shared buffer asynchronous transfer mode (ATM) switch. The designed shared buffer ATM switch has a shared buffet of a pipelined memory which has the access time of 4 ns. The high-speed buffer access time supports a possibility of the implementation of a shared buffer ATM switch which has a large switching capacity. The designed switch architecture provides flexible switching performance and port size scalability with the independence of queue address control from buffer memory control. The switch size and the buffer size of the designed ATM switch can be reconfigured without serious circuit redesign. The designed prototype chip has a shared buffer of 128-cell and 4 ${\times}$ 4 switch size. It is integrated in 0.6um, double-metal, and single-poly CMOS technology. It has 80MHz operating frequency and supports 640Mbps per port.