• 제목/요약/키워드: recover

검색결과 2,734건 처리시간 0.028초

3차원 유한요소해석을 이용한 나노인덴테이션 공정에서의 소재거동해석 및 실험적 검증 (Analysis of Material Deformation Behavior in Nanoindentation Process by using 3D Finite Element Analysis and its Experimental Verification)

  • 이정우;윤성원;강충길
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1174-1177
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    • 2003
  • In this study, to achieve the optimal conditions for mechanical hyper-fine pattern fabrication process, deformation behavior of the materials during indentation was studied with numerical method by ABAQUS S/W. Polymer (PMMA) and brittle materials (Si, Pyrex glass) were used as specimens, and forming conditions to reduce the elastic recover and pile-up was proposed. The indenter was modeled a 3D rigid surface. Minimum mesh sizes of specimens are 1-10nm. Comparison between the experimental data and numerical result demonstrated that the finite element approach is capable of reproducing the loading-unloading behavior of a nanoindentation test. The result of the investigation will be applied to the fabrication of the hyper-fine pattern.

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Subjective Evaluation for Recovery from Visual Strain in Video Data Terminal Operation - How to Recover from Visual Strain in VDT Operation -

  • Muraoka, Tetsuya;Nakashima, Noboru;Ikeda, Hiroaki;Ishizaki, Yoshiaki
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1999년도 제14차 학술회의논문집
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    • pp.189-193
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    • 1999
  • For a video data terminal (VDT) operator, visual strain was caused by continuous VDT operations was found id be recovered by watching the picture of virtual far point with the background of the complementary color when the treatment to recover from visual strain was carried out. When the VDT operator watches the picture of virtual far point with the condition of the complementary color stimuli on the CRT display in 60 or 120 minutes after the start of the VDT operation, the visual strain is recovered and the VDT operator is kept healthy.

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The optimized recover process of heavy minerals from Korean beach-sand

  • Shin, Hee-Young;Jeon, Ho-Soek;Baik, Seung-Woo;Kim, Wan-Tae;Lee, Jae-Chun
    • 한국지구물리탐사학회:학술대회논문집
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    • 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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    • pp.648-653
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    • 2003
  • Optimized recovery of heavy minerals from the near shore sands of Korean Yellow Sea was investigated using physical processing technologies such as gravity concentration and magnetic separation. The head samples were subjected to the three stages effective separation; Head sample was first treated by a spiral separator to recover rough heavy mineral concentrates, which are contained minerals like ilmenite, zircon and rare earth minerals. Much higher beneficiation processes were subsequently taken by wilfley table and magnetic separation according to their magnetic field responses. Heavy minerals were effectively recovered by wilfley table and subsequent recleaning of heavy minerals by magnetic separations was conducted. Qualitative and relative-quantitative analyses of their constituent elements were doing using XRD and XRF.

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추락하는 '대학의 심장', 흔들리는 '사서의 정체성' (Needed to recover : the identity of academic libraries and librarians)

  • 이제환
    • 한국도서관정보학회지
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    • 제28권
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    • pp.505-525
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    • 1998
  • This paper discusses the 'identity' issue of academic libraries and librarians in South Korea. With the rapid social changes, both academic libraries and librarians in South Korea are confronted with a crisis for survival. This paper criticizes the two main social ideology led to such a crisis : namely, the extreme forms of capitalism and technological determinism. To overcome the present crisis, this paper recommends the academic libraries to recover or reform their identity as a cultural, expecially, knowledge organization, not just as an information agency. Also recommended for academic librarians is to make their best effort to be a real professional with the required knowledge and experience.

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전력시장 경쟁체제에서 무효전력/전압 제어 서비스의 가격책정 방법에 관한 연구 (A Method to Calculate a Service Charge for Reactive Power/Voltage Control under Competition of Power Utilities)

  • 노경수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
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    • pp.77-82
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    • 2001
  • As electric power systems have been moving from vertically integrated utilities to a deregulated environment, the charging of reactive power management is a new challenging theme for market operators. This paper proposes a new methodology to compute the costs of providing reactive power management service in a competitive electrical power market. The proposed formulation, which is basically different from those shown in the literature, consists of two parts. One is to recover investment capital costs of reactive power supporting equipment based on a reactive power flow tracing algorithm. The other is to recover operational costs based on variable spot prices using the optimal power flow algorithm. The charging shapes resulted from the proposed approach exhibit a quite good meaning viewed from a practical sense. It turns out that reactive power charges are mostly due to recovery of capital costs and slightly due to recovery of operational costs. The method can be useful in providing additional insight into power system operation and can be used to determine tariffs of a reactive power management service.

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Coupling shape-memory alloy and embedded informatics toward a metallic self-healing material

  • Faravelli, Lucia;Marzi, Alessandro
    • Smart Structures and Systems
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    • 제6권9호
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    • pp.1041-1056
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    • 2010
  • This paper investigates the possibility of a strategy for an automatic full recover of a structural component undergoing loading-unloading (fatigue) cycles: full recover means here that no replacement is required at the end of the mission. The goal is to obtain a material capable of self healing earlier before the damage becomes irreversible. Attention is focused on metallic materials, and in particular on shape memory alloys, for which the recovering policy just relies on thermal treatments. The results of several fatigue tests are first reported to acquire a deep understanding of the physical process. Then, for cycles of constant amplitude, the self-healing objective is achieved by mounting, on the structural component of interest, a suitable microcontroller. Its input, from suitable sensors, covers the current stress and strain in the alloy. The microcontroller elaborates from the input the value of a decisional parameter and activates the thermal process when a threshold is overcome.

Succinylcholine Chloride의 꽃사슴에서의 근이완효과(筋弛緩效果) (The Effect of Succinylcholine Chloride as a Muscular Relaxant in Sika Deers)

  • 김명철;김찬규
    • 대한수의학회지
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    • 제25권2호
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    • pp.203-207
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    • 1985
  • This study was performed to evaluate the effect of succinylcholine chloride as a muscular relaxant in deers. Succinylcholine chloride was administered for the harvesting of velvet antler to 62 sika deers which were farmed in the surburb of Seoul. The results obtained were as follows. 1. The more the dose of succinylcholine the earlier the time to immobilization and the slower the time to recover (p<0.05). 2. The optimal intramuscular dose of succinylcholine was found to be 0.11~0.14mg per kg of body weight for sika deer. 3. The time to immobilization revealed the longest An 4~6 years group. The more the age the longer the time to recover (p<0.05).

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Recovery of Intracel lular Biomaterials from the Suspension of Lysed or Disintegrated Yeast by Membranes

  • Matsumoto, Kanji
    • 한국막학회:학술대회논문집
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    • 한국막학회 1994년도 추계 총회 및 학술발표회
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    • pp.1-6
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    • 1994
  • Many useful biomaterials like enzymes are contained in yeast cells. However, the release of these intracellular biomateriais from the cells is required to recover them with hot water, solvent or various cell breakage methods of mechanical or non mechanical ones. The cell lysis or breakage of yeast is usually made by solvent like ethyl acetate and mechanical disintrgration with high pressure homogenizer or agitating beads mill. The separation of cell debris (i.e. solid liquid separation) is done by centrifuge or membrane depending on the recovery conditions. The features of both separation methods are shown in Tables 1 and 2. As it is often difficult to obtain a clear supernatant by centrifuge from the suspension containing cell debris, the membrane separation is also often used to gel a clear supernatant. In this report we introduce the several applications of membrane separation to separate the cell debris of yeast disintegrated chemically or mechanically and to recover the intracellular biomaterials.

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건조 수침고목재의 원형회복 실험 (Shape recovering trials from dried waterlogged wood)

  • 조규아;박상진
    • 한국문화재보존과학회:학술대회논문집
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    • 한국문화재보존과학회 2004년도 제20회 발표논문집
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    • pp.66-71
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    • 2004
  • When waterlogged wood dries up, it shrinks largely. And it is hard to recover original shape. Therefore it happens to lose the value of wood remains frequently. This paper studied how far dried waterlogged wood can recover original shape. Shape recovering course and extent are thoroughly investigated after waterlogged wood of Pinus densiflora, Quercus serrata and Styrax japonica oven-dries and instills varieties of test solution. At 1- step, oven-dried samples infiltrated by chlorous acid sodium or sodium hydroxide solution. At 2- step, wood tissues of samples were swelled by the fast decompression after infiltrating $CO_2-supercritical$ fluid at high pressure. The study investigated the possibility of shape recovering in waterlogged wood. Shape recovering rate is different with solution and wood species. Sample of sodium hydroxide solution doesn't swell anymore when using $CO_2-supercritical$ fluid. In general, the sample of sodium hydroxide solution has higher Shape recovering rate than $CO_2-supercritical$ fluid solution treated by chlorous acid sodium.

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폐전자부품에서 유가금속 회수기술 (Recovery of Valuable Metal from e-Wasted Electronic Devices)

  • 김유상
    • 한국표면공학회지
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    • 제49권6호
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    • pp.477-485
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    • 2016
  • As expensive and valuable metals being used in electronic and semiconducting industries are abandoned as industrial wastes after use of them, it is required to recover them from e-wasted electronics parts. Gold which is used for printed circuit boards or electronic equipments, accessories, etc., is one of e-Wasted materials and recently indium, gallium, zirconium, cobalt, molybdenum and lithium are bacome valuable metals to be recovered from the e-wastes. Since the amount of precious metals is now being faced with scarcity, lean too much on area and instability of supply, and industrial demands are rapidly increasing every year, it becomes more important to recover the valuable metals from the industrial wastes. In this review, we introduced technologies and research trend of the recovery processes of valuable metals from the e-wastes in high-tech devices over the world.