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ADVANCED TEST REACTOR TESTING EXPERIENCE - PAST, PRESENT AND FUTURE

  • Marshall Frances M.
    • Nuclear Engineering and Technology
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    • v.38 no.5
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    • pp.411-416
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    • 2006
  • The Advanced Test Reactor (ATR), at the Idaho National Laboratory (INL), is one of the world's premier test reactors for providing the capability for studying the effects of intense neutron and gamma radiation on reactor materials and fuels. The physical configuration of the ATR, a 4-leaf clover shape, allows the reactor to be operated at different power levels in the comer 'lobes' to allow for different testing conditions for multiple simultaneous experiments. The combination of high flux (maximum thermal neutron fluxes of 1E15 neutrons per square centimeter per second and maximum fast [E>1.0 MeV] neutron fluxes of 5E14 neutrons per square centimeter per second) and large test volumes (up to 122 cm long and 12.7 cm diameter) provide unique testing opportunities. The current experiments in the ATR are for a variety of test sponsors - US government, foreign governments, private researchers, and commercial companies needing neutron irradiation services. There are three basic types of test configurations in the ATR. The simplest configuration is the sealed static capsule, which places the capsule in direct contact with the primary coolant. The next level of experiment complexity is an instrumented lead experiment, which allows for active control of experiment conditions during the irradiation. The most complex experiment is the pressurized water loop, in which the test sample can be subjected to the exact environment of a pressurized water reactor. For future research, some ATR modifications and enhancements are currently planned. This paper provides more details on some of the ATR capabilities, key design features, experiments, and future plans.

Performance Enhancement by Adaptation of Long Term Chronoamperometry in Direct Formic Acid Fuel Cell using Palladium Anode Catalyst

  • Kwon, Yong-Chai;Baik, S.M.;Han, Jong-Hee;Kim, Jin-Soo
    • Bulletin of the Korean Chemical Society
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    • v.33 no.8
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    • pp.2539-2545
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    • 2012
  • In the present study, we suggest a new way to reactivate performance of direct formic acid fuel cell (DFAFC) and explain its mechanism by employing electrochemical analyses like chronoamperometry (CA) and cyclic voltammogram (CV). For the evaluation of DFAFC performance, palladium (Pd) and platinum (Pt) are used as anode and cathode catalysts, respectively, and are applied to a Nafion membrane by catalyst-coated membrane spraying. After long DFAFC operation performed at 0.2 and 0.4 V and then CV test, DFAFC performance is better than its initial performance. It is attributed to dissolution of anode Pd into $Pd^{2+}$. By characterizations like TEM, Z-potential, CV and electrochemical impedance spectroscopy, it is evaluated that such dissolved $Pd^{2+}$ ions lead to (1) increase in the electrochemically active surface by reduction in Pd particle size and its improved redistribution and (2) increment in the total oxidation charge by fast reaction rate of the Pd dissolution reaction.

Structural Equation Modeling on Smoking Cessation Intention in Male Technical High School Students (특성화고등학교 남학생의 금연의도 구조모형)

  • Do, Eun Su;Choi, Eunsuk
    • Journal of Korean Academy of Nursing
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    • v.47 no.2
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    • pp.211-221
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    • 2017
  • Purpose: This study was done to develop and test a structural model on smoking cessation intention in technical high school men. The conceptual model was based on the theory of reasoned action and health promotion model. Methods: From May 29 to April 13, 2015, 413 technical high school students who smoked completed a structured questionnaire. Data were analyzed to calculate the direct and indirect effects of factors affecting smoking cessation intention. The SPSS WIN 20.0 and AMOS 21.0 programs were used. Results: The hypothetical model was a good fit for the data. The model fit indices were $x^2/df=2.36$, GFI=.95, AGFI=.92, NFI=0.97, and RMSEA=.05. Self-esteem had direct and indirect effects on smoking cessation intention. Attitude, subjective norm, and self-efficacy had direct effects on smoking cessation intention. Smoking knowledge and environmental factor had indirect effects on smoking cessation intention. This model explained 87.0% of the variance in smoking cessation intention. Conclusion: These results indicate that technical high school students' intention to stop smoking can be improved through an increase in self-esteem, negative environmental factors, attitude toward smoking cessation, subjective norm about smoking cessation, and self-efficacy for smoking cessation.

Solid Freeform Fabrication of Metal Prototype Using Direct Metal Shaping Process (직접식 금속 적층공정을 이용한 금속 시제품 제작)

  • Kim, Jae-Do;Park, Jin-Yong;Cho, Myeong-Woo
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.10
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    • pp.56-62
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    • 2000
  • A fast and precise technique to make 3-dimensional object which is called direct metal shaping process is processed. It is very useful technique in design and inspection. Using this developed system, a solid object is made. In experiment, test parts are built by varying three factors, laser power, scan path, scan speed. This process used device, which is different from the widely used in rapid prototyping in that powder feeding device is used. Spraying powder directly at the focused laser beam and then three dimensional object is made by the deposit of melted metal powder. The optimum scanning path is found to be zigzag path, which had little thermal affection on base metal. As a result of these experiments, it was found that optimum scanning speed is 15mm/sec laser power is 50W. This constructed 3-dimensional object could be used in mold manufacturing directly.

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Performance of Air-Water Direct Contact Heat Exchanger Linked to Heat Pump (히트펌프에 연계된 공기-물 직접접촉식 열교환기의 성능)

  • Kim, Y.H.;Keum, D.H.;Ryou, Y.S.;Kang, Y.K.;Kim, J.G.;Jang, J.K.;Lee, H.M.
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.80.2-80.2
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    • 2011
  • Fossil fuel was a major energy resource but the consumption of fossil fuel will decrease gradually because of limited deposits and non-environmental features. In contrast, because the renewable energy resources are infinite and sustainable, their consumption has increased annually. To promote the supply of these infinite natural energy we have to develop more efficient and inexpensive heat recovery system. In this study a simple device was designed as a heat exchanger, that is a direct contact heat exchanger. This heat exchanger was manufactured in cylindrical shape with height of 1,500 mm and diameter of 1,000 mm. To test the efficiency of this heat exchanger, it was connected to the evaporator of heat pump system. During the experimental tests, the humid air of $10{\sim}30^{\circ}C$ was supplied to this air-to-water heat exchanger and then the water flow rate was set to 2500~3500 L/h. Heat recovery rate of this heat exchanger increased in proportion to entering air temperature and water flow rate.

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In-cylinder Spray Flow Characteristics in Direct-injection Gasoline Engine (직접 분사식 가솔린 엔진의 실린더 내 분무 유동 특성에 관한 연구)

  • 김진수;전문수;윤정의
    • Transactions of the Korean Society of Automotive Engineers
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    • v.8 no.6
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    • pp.51-59
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    • 2000
  • In-cylinder spray flow motion plays an important in the adjustment of mixture preparation with a fundamental spray characteristics and in-cylinder flow field well in direct-injection gasoline engine. In this study, the fundamental spray characteristics such as mean drop size, velocity distribution, spray angle were measured and in-cylinder spray flow motion was visualized in order to optimize intake port, piston top land and combustion chamber shapes in the development stage of mass-produced G야 engine. For these experiments, the PDPA measurements and Mie scattering technique were used for detailed spray characteristics and in-cylinder spray motions were obtained by use of ICCD camera through the single-cylinder optical engine. From the experimental results, the test injector shows a good low-end linearity between the dynamic flow and fuel injection pulse width and the fuel spray of 20mm or less in SMD with good spray symmetry. In addition, the in-cylinder tumble flow has more effect on the homogeneous mixture formation than that of in-cylinder swirl flow at early injection mode and the in-cylinder swirl flow plays a better role of stratified mixture preparation than tumble flow at late injection mode.

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A Study on CRM in Discount Store of Fashion Product (2) - Focus on Customer's Age - (대형할인점(大形割引店)에서의 패션 제품(製品) CRM에 관(關)한 연구(硏究)(제2보)(第2報) - 연령대(年齡代)의 차이(差異)를 중심(中心)으로 -)

  • Lee, Seung-Hee;Huh, Song-Hee
    • Journal of Fashion Business
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    • v.11 no.1
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    • pp.97-107
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    • 2007
  • The purpose of this study was to examine the relationship structure in discount store focusing on age. Subjects for this study were 360 customers who had purchased fashion products in discount stores. For date analysis, $x^2$-test and regression analysis were used. As the result, when comparing groups by the age, women in their 20s, 30s and 40s had 'relationship maintenance intention' through satisfaction, trust and commitment. In the case of women in their 20s group, the information, reputation, product salesperson and price variables had the effects on satisfaction. The information, location, salesperson variable had direct effect on relationship maintenance. In the case of women in their 30s group, the benefits, information, reputation and price variables had the effects on satisfaction. And the information, salesperson variable had direct effect on relationship maintenance. In the case of women in their 40s group, the information, location and price variables had the effects on satisfaction. The reputation variable had direct effect on relationship maintenance. Based on these results, fashion marketing strategies of discount store would be suggested.

Estimation of Genetic Parameters for Wool Traits in Angora Rabbit

  • Niranjan, S.K.;Sharma, S.R.;Gowane, G.R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.10
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    • pp.1335-1340
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    • 2011
  • Different genetic parameters for weaning weight and wool traits were estimated using restricted maximum likelihood (REML) in Angora rabbits. Total wool yield of first (I), second (II) and third (III) clips were taken as a separate trait under study. The records from more than 2,700 animals were analysed through fitting six animal models with various combinations of direct and maternal effects. A log likelihood ratio test was used to select the most appropriate model for each trait. Direct heritability estimates for the wool traits were found to be moderate to high across different models. Heritability estimates obtained from the best model were 0.24, 0.22, 0.20 and 0.21 for weaning weight, clip I, II and III; respectively. Maternal effects especially due to permanent environment had higher importance at clip I and found to be declining in subsequent clips. The estimates of repeatability of doe effect on wool traits were 0.44, 0.26 and 0.18 for clip I, II and III; respectively. Weaning weight had moderately high genetic correlations with clip I (0.57) and II (0.45), but very low (0.11) with clip III. Results indicated that genetic improvement for wool yield in Angora rabbit is possible through direct selection. Further, weaning weight could be considered as desirable trait for earliest indirect selection for wool yield in view of its high genetic correlation with wool traits.

The Relations of Nurses' Job Stress and Knowledge, Attitude and Care Behavior for Elderly Patients (간호사의 직무스트레스와 노인에 대한 지식, 태도 및 케어실천행위)

  • Yoon, Sook-Hee
    • Journal of Korean Academy of Nursing Administration
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    • v.15 no.4
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    • pp.593-600
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    • 2009
  • Purpose: This study was to examine the relation of nurses' job stress and knowledge, attitude and care behavior for elderly patient in hospitals. Method: One hundred ninety one nurses caring the elderly patients in hospitals in Ilsan, Busan and Gyeongsangnam-do were subjects. The data was collected between Sept. 21 and 31, 2009. Data was analyzed using t-test, ANOVA, Pearson correlation with SPSS/Win 17.0 and the fitness of pathway models with AMOS 5.0. Results: The mean scores of job stress and knowledge were in middle range, and attitude and care behavior were in a little higher range. The fitness of hypothetical model was excellent. Job stress had direct effects on attitude and care behavior, knowledge had direct effect on attitude and attitude had direct effect on care behavior. But the pathways related to job stress and attitude and job stress and care behavior were not significant. In modified model deleted the pathway between job stress and attitude, the pathway related to job stress and behavior also was not significant. Conclusion: Education related to the elderly for nurses to improve care behavior is needed continuously.

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A Study on Characteristic of the Bio-ethanol Produced on Fruit Wastes for Direct Ethanol Fuel Cell (DEFC) (과일폐기물을 이용한 DEFC용 바이오에탄올 제조 및 특성에 관한 연구)

  • Lee, Nam-Jin;Kim, Hyun-Soo;Cha, In-Su;Choi, Jeong-Sik
    • Journal of Hydrogen and New Energy
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    • v.22 no.2
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    • pp.257-264
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    • 2011
  • This study discribes performance of DEFC (Direct Ethanol Fuel Cell) utilized bio-ethanol based on fruit wastes. To produce the bio-ethanol, fruit wastes were treated at temperature $120^{\circ}C$ and 90minutes in acid pre-treatment. After pre-treatment was done, alcohol fermentation process was running. Initial alcohol concentration was 5%. Using the multi coloumn distillation system, more than 95% ethanol was distilled and each component of bio-ethanol was analyzed. In DEFC performance test, it was revealed that cell performance was much higher than that of ethanol. Comparing ethanol with mixed fuel (bio-ethanol (10%) + ethanol (90%)), the performance of ethanol was higher than that of mixed fuel. Even though the bio-ethanol from the fruit wastes is corresponded with transport ethanol standards, it thought that organic matter in bio-ethanol could be negative effect on fuel cell.