• Title/Summary/Keyword: S-Buffer

검색결과 1,780건 처리시간 0.031초

Analysis of Functional Criteria for Buffer Material in a High-level Radioactive Waste Repository

  • W. J. Cho;Lee, J. O.;K. S. Chun;Park, Hyun-Soo
    • Nuclear Engineering and Technology
    • /
    • 제31권1호
    • /
    • pp.116-132
    • /
    • 1999
  • This study is intended to analyze the requirements of a buffer material that is one of the major components of the engineered barriers in a high-level radioactive waste repository. The characteristics of potential materials for the buffer in the repository were analyzed and a candidate material was selected. And, based on the current knowledge and the information from various sources, the requirements of a buffer material were evaluated. Finally its quantitative functional criteria on the generic viewpoint has been recommended to be supplied as a guideline for the development of the reference disposal concept and the related buffer material in Korea. The criteria are composed of seven major items, such as hydraulic conductivity, retardation capacity, swelling potential and swelling pressure, thermal conductivity, longevity, organic matter content, and mechanical properties.

  • PDF

AN ANALYSIS OF THE THERMAL AND MECHANICAL BEHAVIOR OF ENGINEERED BARRIERS IN A HIGH-LEVEL RADIOACTIVE WASTE REPOSITORY

  • Kwon, S.;Cho, W.J.;Lee, J.O.
    • Nuclear Engineering and Technology
    • /
    • 제45권1호
    • /
    • pp.41-52
    • /
    • 2013
  • Adequate design of engineered barriers, including canister, buffer and backfill, is important for the safe disposal of high-level radioactive waste. Three-dimensional computer simulations were carried out under different condition to examine the thermal and mechanical behavior of engineered barriers and rock mass. The research looked at five areas of importance, the effect of the swelling pressure, water content of buffer, density of compacted bentonite, emplacement type and the selection of failure criteria. The results highlighted the need to consider tensile stress in the outer shell of a canister due to thermal expansion of the canister and the swelling pressure from the buffer for a more reliable design of an underground repository system. In addition, an adequate failure criterion should be used for the buffer and backfill.

ATM에서 공정한 QoS 제공을 위한 문턱간 기반 버퍼 관리 알고리즘 (Threshold Based Buffer Management Algorithm for Fair QoS in ATM)

  • 고유신;강은성;고성택
    • 융합신호처리학회 학술대회논문집
    • /
    • 한국신호처리시스템학회 2003년도 하계학술대회 논문집
    • /
    • pp.230-233
    • /
    • 2003
  • ATM 트래픽 관리의 목적은 호 설정시 요구하는 QoS를 충족시키는 것과 최소한의 망 자원을 이용하면서 망을 보호하는 것이다. 또한, 서로 다른 채널간 QoS을 공정하게 보장하는 것이 필요하다. 본 논문에서는 채널들간에 공정한 QoS 제공과 링크 이용률을 높이기 위하여 입력버퍼에 문턱값을 기반으로 출력 셀율을 동적으로 조정하는 새로운 TBBM(threshold based buffer management)알고리즘을 제안하였으며 문턱값 변화에 따른 성능을 분석하였다.

  • PDF

Coating of ZnS phosphor by $SiO_2$ sol-gel

  • Lee, You-Hui;Han, Sang-Do;Han, Chi-Hwan;Yang, Hua;Singh, Ishwa
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
    • /
    • pp.719-723
    • /
    • 2004
  • Silica coating on ZnS particles with buffer solution has been investigated. Diluted sodium silicate in water was used as the precursor material and it was diluted in water. Sodium silicate was added drop-wise in the continuously stirred suspension of ZnS in the buffer solution at room temperature. Smooth and evenly distributed silica coated ZnS phosphors has been obtained when the pH of buffer solution was 10, the concentration of sodium silicate in water was 20 wt%, firing temperature was 500 $^{\circ}C$.

  • PDF

Effect of ZnS Buffer Layer on Inorganic EL Device

  • Kim, Duck-Gon;Park, Lee-Soon;Kum, Tae-Il;Lee, Sang-Mok;Sohn, Sang-Ho;Jung, Sang-Kooun
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
    • /
    • pp.1629-1631
    • /
    • 2007
  • Significant process in the performance and commercialization of full-color thin-film electroluminescent(EL) displays has been achieved. This is due to the remarkable progress made in the performance of exiting EL phosphors, development of new phosphor materials, and design of new EL phosphor structures. In this paper, we fabricated thinfilm EL devices with ZnS buffer and $BaTiO_3$ electric layer with on top and bottom of phosphor layer. The effect of ZnS and $BaTiO_3$ layer on the luminance of EL device were studied.

  • PDF

2차 버퍼층 ZnMgO 박막의 Mg/(Mg+Zn) 비율 조절을 통한 SnS 박막 태양전지 효율 향상 (Improving the Efficiency of SnS Thin Film Solar Cells by Adjusting the Mg/(Mg+Zn) Ratio of Secondary Buffer Layer ZnMgO Thin Film)

  • 이효석;조재유;윤성민;정채환;허재영
    • 한국재료학회지
    • /
    • 제30권10호
    • /
    • pp.566-572
    • /
    • 2020
  • In the recent years, thin film solar cells (TFSCs) have emerged as a viable replacement for crystalline silicon solar cells and offer a variety of choices, particularly in terms of synthesis processes and substrates (rigid or flexible, metal or insulator). Among the thin-film absorber materials, SnS has great potential for the manufacturing of low-cost TFSCs due to its suitable optical and electrical properties, non-toxic nature, and earth abundancy. However, the efficiency of SnS-based solar cells is found to be in the range of 1 ~ 4 % and remains far below those of CdTe-, CIGS-, and CZTSSe-based TFSCs. Aside from the improvement in the physical properties of absorber layer, enormous efforts have been focused on the development of suitable buffer layer for SnS-based solar cells. Herein, we investigate the device performance of SnS-based TFSCs by introducing double buffer layers, in which CdS is applied as first buffer layer and ZnMgO films is employed as second buffer layer. The effect of the composition ratio (Mg/(Mg+Zn)) of RF sputtered ZnMgO films on the device performance is studied. The structural and optical properties of ZnMgO films with various Mg/(Mg+Zn) ratios are also analyzed systemically. The fabricated SnS-based TFSCs with device structure of SLG/Mo/SnS/CdS/ZnMgO/AZO/Al exhibit a highest cell efficiency of 1.84 % along with open-circuit voltage of 0.302 V, short-circuit current density of 13.55 mA cm-2, and fill factor of 0.45 with an optimum Mg/(Mg + Zn) ratio of 0.02.

멀티미디어 통신 환경에서 Push/Pull 버퍼 관리 기법 (A Scheme for Push/Pull Buffer Management in the Multimedia Communication Environments)

  • 정찬균;이승룡
    • 한국정보처리학회논문지
    • /
    • 제7권2S호
    • /
    • pp.721-732
    • /
    • 2000
  • Multimedia communication systems require not only high-performance computer hardwares and high-speed networks, but also a buffer management mechanism to process many data efficiently. Two buffer handling methods, Push and Pull, are commonly used. In the Push method, a server controls the flow of dat to a client, while in the Pull method, a client controls the flow of data from a server. Those buffering schemes can be applied to the data transfer between the packet receiving buffer, which receives media data from a network server, and media playout devices, which play the recived media data. However, the buffer management mechanism in client-sides mainly support either one of the Push or the Pull method. Consequently, they have some limitations to support various media playout devices. Futhermore, even though some of them support both methods, it is difficult to use since they can't provide a unified structure. To resolved these problems, in this paper, we propose an efficient and flexible Push/Pull buffer management mechanism at client-side. The proposed buffer management scheme supports both Push and Pull method to provide various media playout devices and to support buffering function to absorb network jitter. The proposed scheme can support the various media playback devices using a single buffer space which in consequence, saves memory space compared to the case that a client keeps tow types of buffers. Moreover, it facilitates the single buffer as a mechanism for the absorbing network jitter effectively and efficiently. The proposed scheme has been implemented in an existing multimedia communication system, so called ISSA (Integrated Streaming Service Architecture), and it shows a good performance result compared to the conventional buffering methods in multimedia communication environments.

  • PDF

3GPP ARQ를 위한 재정렬 버퍼의 점유량 조절 방식 (Occupancy Control Scheme for Reordering Buffer at 3GPP ARQ)

  • 신우철;박진경;하준;최천원
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2003년도 하계종합학술대회 논문집 I
    • /
    • pp.65-68
    • /
    • 2003
  • 3GPP's RLC protocol specification adopted an error control scheme based on selective repeat ARQ. In 3GPP ARQ, distinctive windows are provide at transmitting and receiving stations so that those stations are prohibited to send or receive data PDU's out of window. An increase in window size enhances delay performance. Such an increase, however, raises the occupancy at reordering buffer, which results in a long reordering time. Aiming at suppressing the occupancy at reordering buffer, we propose a occupancy control scheme in this paper. In this scheme, a threshold is created in the receiving station's window and a data PDU out of the threshold (but within the window) is treated according to go back N ARQ. By the employment of the occupancy control scheme, the occupancy at the reordering buffer is apparently reduced, while the delay performance may be degraded due to the properties of go back N ARQ. We, thus, investigate the peak occupancy and mean delay performance by a simulation method. From numerical examples, we observe a trade-off in both performance measures and conclude that the peak occupancy is effectively reduced by setting a proper threshold under a constraint on mean delay performance.

  • PDF

PLD법을 이용한 Ni과 NiW기판위에 Ce$O_{2}$YSZ/$Y_{2}$$O_{3}$완충층 증착 (Deposition of Ce$O_{2}$YSZ/$Y_{2}$$O_{3}$ buffer layers on Ni and NiW substrate by PLD)

  • D. Q. Shi;R. K. Ko;K. J. Song;J. K. Chung;Park, S. J.;J. Yang;S. I. Yoo;Park, C.
    • 한국초전도저온공학회:학술대회논문집
    • /
    • 한국초전도저온공학회 2003년도 추계학술대회 논문집
    • /
    • pp.139-141
    • /
    • 2003
  • Multiple CeO$_2$/YSZ/Y$_2$O$_3$buffer layers, and subsequent YBCO films were deposited on the biaxially textured pure Ni and Ni + 3at%W substrates using pulsed laser deposition. The deposition conditions of buffer layers on Ni and NiW were studied and compared. Good biaxial textures of buffer layers have been obtained on both substrates. The Jc's of YBCO films on these metal substrates were greater than 1$\times$10$^{6}$ A/$\textrm{cm}^2$ at 77K, 0T.

  • PDF