• 제목/요약/키워드: T140

검색결과 772건 처리시간 0.034초

보일러 급수 펌프의 과도진동 연구 사례 - 실험 및 신호처리를 중심으로 -

  • 김정태;임병덕;이현
    • 소음진동
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    • 제1권2호
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    • pp.129-140
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    • 1991
  • The boiler feed pump located at a power plant has been experienced a severe vibration since the plant began to service in early 1980. The research is focused on the field measurement and implementation of simple signal processing techniques in order to provide realistic and effective solution which could be implemented into the plant. Based on the root cause analysis for the trouble-making pump system, the driving part gear in the fluid coupling system is identified as a potential source. The followed verification test confirms the analytical result. The test result shows that vibration reduction obtained after the gear replacement reaches up 15.8 dB, which is 1/6 times of the vibration level compared to that of the troble-making pump. The measured vibration level of the pump satisfies the manufacture criteria and guarantees the smoothed operation.

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The Regulatory Domain of Troponin C: To Be Flexible or Not To Be Flexible

  • Gagne, Stephane M.;Sykes, Michael T.;Sykes, Brain D.
    • 한국자기공명학회논문지
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    • 제2권2호
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    • pp.131-140
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    • 1998
  • The calcium-induced structural changes in the skeletal muscle regulatory protein troponin C (NTnC) involve a transition from a ‘closed’to an ‘open’structure with the concomitant exposure of a large hydrophobic interaction site for target proteins. Structural studies have served to define this conformational change and elucidate the mechanism of the linkage between calcium binding and the induced structural changes. There are now several structures of NTnC available from both NMR and X-ray crystallography. Comparison of the calcium bound structures reveals differences in the level of opening. We have considered the concept of a flexible open state of NTnC as a possible explanation for this apparent discrepancy. We also present simulations of the closed-to-open transition which are in agreement with the flexibility concept and with experimental energetics data.

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임상간호사의 소진에 직무스트레스, 대처, 자기효능감이 미치는 영향 (Influences of Job Stress, Coping, Self-efficacy on Burnout of Clinical Nurses)

  • 이지원
    • 수산해양교육연구
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    • 제26권5호
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    • pp.1003-1012
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    • 2014
  • The purpose of this study was to understand the clinical nurses' burnout, job stress, coping, self-efficacy and to identify the factors that influence on burnout. A quantitative, descriptive design was used to study 140 clinical nurses in B and U city, recruited from June to July, 2012. The data were analyzed SPSS 20.0 program using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients and stepwise multiple regression. The mean score for burnout was 2.28 points(range: 1-4). Burnout was significantly correlated with job stress, coping and self-efficacy. These variables accounted for 37.4% of burnout. Based on the results, the sorts of strategies to reduce the burnout are required by offering job stress, coping and self-efficacy management.

유우원(乳牛源) 대장균군세균(大腸菌群細菌)의 치사열(致死熱)에 관한 연구 (Survival and Thermal Inactivation of Coliform Bacteria after the Heat Treatment at 143°F)

  • 정길택;한홍율
    • 대한수의학회지
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    • 제11권2호
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    • pp.137-140
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    • 1971
  • Survival and thermal inactivation after heat treatment at $143^{\circ}F$ were observed among 27 strains of coliform bacteria isolated from dairy cattle. The results obtained were as follows. 1. The obvious differences in heat-sensitivity were observed among the strains tested. 2. No strain was found resistant to the heat treatment of $143^{\circ}F$ for 30 minutes. 3. A marked effect of density of coliform bacteria on the survival after the heat treatment was observed. As the density of coliform bacteria was increased, the rate of survival was increased markedly regardless of the length of heat treatment.

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Identification of the process in closed-loop control system

  • Oura, Kunihiko;Akizuki, Kageo;Hanazaki, Izumi
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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    • pp.140-145
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    • 1994
  • In this paper, we consider a problem to estimate process parameters using input-output data collected from the process operating in closed-loop control system. When orders and delay-time of the process are known correctly, under some conditions of identifying experiments, it is reported that accurate identification results can be obtained by applying prediction error method. To get accurate estimates, it is necessary to know orders and delay-time of the process. It is difficult to determine them in closed-loop identification, because ill-condition for identification are easily caused by selection of unsuitable order or delay time. Furthermore, the procedures to select orders and delay-time in open-loop identification aren't always available in closed-loop identification. The purpose of this paper is to determine a delay-time under suitable assumption that order of the process are known as the first step.

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보강재 설치 간격에 따른 지오그리드 보강토옹벽의 변형거동에 관한 모형실험 (Model Tests on Behavior of Geogrid Reinforced Soil Walls with Vertical Spacing of Reinforcement Layers)

  • 조삼덕;이광우;오세용
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2004년도 춘계학술발표회
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    • pp.372-379
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    • 2004
  • The model tests were conducted to assess the behavior characteristics of geogrid reinforced earth walls according to various surcharge loads and reinforcement spacing. The models were built in the box having dimension, 100cm tall, 140cm long, and 100cm wide. The reinforcement used was geogrid(tensile strength 2.26t/m). Decomposed granite soil(ML) was used as a backfill material. The LVDTs were installed on the model retaining walls to obtain the displacements of the facing. In the results, the maximum displacement of facing and tensile strain of geogrid was measured at 0.7H(H is wall height) from the bottom of reinforced wall.

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극초고압영역에서의 디젤연료의 자유분무특성에 관한 연구 (A Study on Spray Characteristics Analysis of Free Spray of Diesel Fuel with Ultra High Pressure)

  • 정대용;이종태;홍기배
    • 한국분무공학회지
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    • 제7권4호
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    • pp.16-22
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    • 2002
  • The characteristics of free spray with ultra injection pressure was analyzed to clear the limit pressure of diesel engine. To obtain final goal, ultra high pressure injection equipment was developed, spray patterns were visualized under various ultra injection pressures. Spray penetration and spray width, volume and entrained air mass were increased with the increase of injection pressure. Sauter mean diameter and injection durstion wert decreased. But over 3,000bar of ultra injection pressure region the rates of increase show almost similar and finally the reversed tendencies at 4,140bar.

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고온 크리프 구조물의 장시간 한계응력강도 예측 (Prediction of Long-Term Stress Intensity Limit of High-Temperature Creep Structures)

  • 김우곤;류우석;김현희
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.648-653
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    • 2003
  • In order to predict stress intensity limit of high-temperature creep structures, creep work-time equation, defined as $W_ct^P=B$, was used, and the results of the equation were compared with isochronous stress-strain curve (ISSC) ones of ASME BPV NH Code. For this purpose, the creep strain tests with. time variations for commercial type 316 stainless steel were conducted with different stresses; 160 MPa, 150 MPa, 145 MPa, 140 MPa and 135 MPa at $593^{\circ}C$. The results of log $W_c$ and log t plots showed a good linear relation up to $10^5$ hr. The constants p, B and stress intensity limit values showed comparatively good agreement to those of ASME NH ISSC. It is believed that the relation can be simply obtained with only several short-term 1% strain data without ISSC which can be obtained by long-term creep data.

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용제염색에 관한 기초적 연구 제2보 물, TCE 및 물/TCE 처리를 한 PET의 염색성 (A Foundamental Study on the Solvent Dyeing Part 2. Dyeing Properties of PET Treated with Water, TCE and water/TCE Emulsion)

  • 정두진
    • 한국의류학회지
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    • 제3권2호
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    • pp.37-41
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    • 1979
  • In order to obtain tasic information for solvent dyeing, polyethylene terephthalate (PET) films was pretreated with water, tetrachloroethylene (TCE) and water/TCE emulsion for three hours at $140^{\circ}C$ for stabilizing the substrate. By film roll cyliderical method, Disperse Red 60, Disperse Yellow 42, and Disperse Blue 27 were diffused in the films and examined dyeing properties. The results are summarized as follows; 1) Diffusion coefficient increases in the order, waterTCE>water/TCE 2) A linear relationship between diffusion coefficient and shrinkage was Observed 3) The temperature dependence of the diffusion coefficient can't be expressed by WLF equation.

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