• Title/Summary/Keyword: Working Power

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Effect of Cold Working on the Tensile Strength of Fe-26Mn-4Co-2Al Damping Alloy (Fe-26Mn-4Co-2Al 제진합금의 인장강도에 미치는 냉간가공의 영향)

  • Kang, Chang-Yong;Kim, Seong-Hwi;Jeong, Gyu-Seong
    • Journal of Power System Engineering
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    • v.20 no.6
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    • pp.46-50
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    • 2016
  • This study was carried out to investigate the effect of cold working on the tensile strength of Fe-26Mn-4Co-2Al damping alloy. ${\alpha}^{\prime}$ and ${\varepsilon}$-martensite were formed by cold working, and martensite was formed with the specific direction and surface relief. With the increasing degree of cold rolling, volume fraction of ${\alpha}^{\prime}$-martensite was increased, whereas the volume fraction of ${\varepsilon}$-martensite was decreased after rising to maximum value at specific lever of cold rolling. Tensile strength was linearly increased with an increasing of degree of cold rolling. Tensile strength was strongly affected to the volume fraction of ${\varepsilon}$-martensite formed by cold working, but the effect of volume fraction of ${\varepsilon}$-martensite on the tensile strength was not observed.

Applying Cases of Manipulator for Live Working on Internal and External Distribution Lines (국내외 배전 활선작업 Manipulator 적용현황)

  • Kim, Jae-Hoon;Kim, Seung-Ho;Kim, Dae-Sik;Park, Kang-Sik;Lee, Heung-Ho;Han, Sang-Ok
    • Proceedings of the KIEE Conference
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    • 2005.07e
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    • pp.118-120
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    • 2005
  • Nowadays, economical and social environments are changing to the type of an advanced country for development of techniques in power industry. So most of workers are recently avoiding the 3D works and asking for safety of working environment, etc. in highly dangerous parts such as hot line working on distribution lines, especially. Therefore, most advanced countries are using the support-arm or robotic systems on distribution line works for securing the construction reliability, economical feasibility and protection of linemen from the electric shock and so forth. In special Japanese electric power companies are using the robotic system named manipulator. In Korea, a support-arm has been developed for safety and facility in live working on distribution lines but not widely supplied. In this paper we will introduce development cases of support arm and manipulator robot for live working on distribution lines.

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Parenting Stress Changes in Both of Continuous Working and Non-Working Mothers After the Birth of Their First Child : A Focus on the Effects of the Values, Knowledge and Expectations about Their Children (첫 자녀 출산 후 취업모와 전업모의 양육스트레스 변화 : 자녀가치, 양육지식, 자녀미래기대가 미치는 영향을 중심으로)

  • Song, Young Joo;Lee, Mi Ran;Chun, Hui Young
    • Korean Journal of Child Studies
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    • v.35 no.5
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    • pp.15-35
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    • 2014
  • The purpose of this study was to investigate parenting stress changes in both continuous working and continuous non-working mothers after the birth of their first child and their relationships with the cognitive variables about child-rearing, using the 3rd Panel Study on Korean Children(PSKC) by the Korea Institute of Child Care and Education(KICCE). The results revealed that the parenting stress of the non-working mothers was higher than the stress experienced by the working mothers. The increase in stress was only found both groups between the second year and the third year of childbirth. The total explanatory power of the knowledge, values and expectations regarding their children saw stress increase for the working mothers, but saw it decrease for the non-working mothers. Finally, the emotional value surrounding parenthood was the most powerful variable for both groups, with the exception of the non-working mothers' stress, as experienced in the first year.

Effects of inlet working condition and heat load on supercritical CO2 compressor performance

  • Jinze Pei;Yuanyang Zhao;Mingran Zhao;Guangbin Liu;Qichao Yang;Liansheng Li
    • Nuclear Engineering and Technology
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    • v.55 no.8
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    • pp.2812-2822
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    • 2023
  • The supercritical carbon dioxide (sCO2) Brayton power cycle is more effective than the conventional power cycle and is more widely applicable to heat sources. The inlet working conditions of the compressor have a higher influence on their operating performance because the thermophysical properties of the CO2 vary dramatically close to the critical point. The flow in the sCO2 compressor is simulated and the compressor performance is analyzed. The results show that the sCO2 centrifugal compressor operates outside of its intended parameters due to the change in inlet temperature. The sCO2 compressor requires more power as the inlet temperature increases. The compressor power is 582 kW when the inlet temperature is at 304 K. But the power is doubled when the inlet temperature increases to 314 K, and the change in the isentropic efficiency is within 5%. The increase in the inlet temperature significantly reduces the risk of condensation in centrifugal compressors. When the heat load of the sCO2 power system changes, the inlet pressure to the turbine can be kept constant by regulating the rotational speed of compressors. With the increase in rotational speed, the incidence loss and condensation risk increase.

Performance Analysis of Ejector-Pump Thermal Energy Conversion System Using Various Working Fluids (이젝터-펌프 온도차발전시스템의 작동유체별 성능분석)

  • Yoon, Jung-In;Seol, Sung-Hoon;Son, Chang-Hyo;Choi, Kwang-Hwan;Kim, Young-Bok;Lee, Ho-Saeng;Kim, Hyeon-Ju;Moon, Jung-Hyun
    • Journal of Power System Engineering
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    • v.20 no.6
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    • pp.87-92
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    • 2016
  • This research dealt with performance characteristics of OTEC system applying an ejector and additional pump. Each system using five kinds of working fluids was analyzed, and primary parameters with respect to entrainment ratio were examined: Turbine gross power, evaporation capacity, pump work, efficiency and volume flow ratio. The primary results were as following. The efficiency of ejector-pump OTEC system was dependent on entrainment of the ejector. The degree of efficiency change was different from applied working fluid, and amount of pump work was turned out to be primary factor affected system efficiency. Meanwhile, optimized entrainment ratio was different from applied working fluid since their different vapor density. System efficiency at optimized entrainmet ratio of each working fluid was around 5%, showing minor difference each other.

A Study on the Working Environment Recognition and the Caracter Disposition of Nurse Aides (간호조무사의 근무환경인식과 성격성향에 관한 연구)

  • Lee Sun Yi
    • Journal of Korean Public Health Nursing
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    • v.4 no.1
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    • pp.57-74
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    • 1990
  • As the whole world took on the tendency to be highly industrialized, it became necessary for each field of occupation to require professional man power. Especially, since the World War n, the participation of woman power in economic activities has been continually increasing. In our country also, because of the rapid economic growth, change in the way of thinking of women as well as their participation in economic activities are increasing. Thus, woman power is being utilized in various occupational fields from simple physical labor to those that require high-professional skill. Also, continued economic development policies, by setting the establishment of welfare society as the ideology to be fulfilled, brought expansion of medical facilities in the field of public health and increase in man power in that field. As for the nursing specialists, more than 6000 have been being produced per year and as of the end of 1988, the total number of nursing specialists, reached 123, 115. Therefore, this study is done to recognize the professional knowledge and ability of nursing specialists, who take up $40\%$ of the total public-health related man power in our country, through evaluating their working environment and their disposition of character. This study, which was done from September 18th to September 30th 1989, took on the method of using formed questionnaires that had been amended and supplemented during two preparatory investigations, 322 of such questionnaires were used as an analytical material. In the formation of questionnaires, 12 questions were related to the working environment, and 26 in fortotal were related to the disposition of character, 5 for wise-disposition, 11 for activedisposition and 10 for open-disposition. The measuring method, which used 5-point-standard, allowed 5 points for affirmative recognition of the working environment, also 5 points for showing wise, active and open disposition of character and only point in opposite cases. Collected materials were analyzed, through an electronic calculation, into the average value, the standard deflection percentage, pearson corelative number and stepwise multiple regression. Summarizing the results from this study is as follows: 1. It was shown that the nursing specialists with the average of 3.07 have affirmative recognition of their working environment. The questions which drew most affirmative reaction were those concerning finance-management system such as hand, the questions that received negative reaction were those concerning communication method with the average of 2.49. Such reaction seems to have resulted from the cramming regulation by the superior authorities. Concerning the recognition of working environment in relation to employment conditions, more affirmative recognition is shown with the average of 3.14. at hospitals where injection job is not performed. The nursing specialists working at regular hospitals show more affirmative recognition than those at general hospitals, the averages being respectiely 3.16 and 3.03. 2. As for the disposition of character of the nursing specialists, active-disposition was highest with the average of 3.38, next was wise-disposition with 3.20 and the lowest was open-diposition with 2.98. Variable-wise disposition of character shows that wise-disposition and academic background are beneficially correlated by 0.12. Ative-disposition and open-disposition show correlation to the office term by respectively 0.16 and 0.21. In other words. better academic background leads to higher wise-disposition and more - experience results in higher active and open disposition. Also, the class that performs the injection job, in relation to the working environment, might cause change in the self-conceit that identify those in that class with the nurses; however, as far as professional judgment and action, in dealing with nursing job, being wise, active and open is concerned, not much effect is made. 3. The relation between the recognition of the working environment and the disposition of character is that more afirmative recognition- a nursing specialist has about her working environment, the higher the active-disposition becomes by 0.13. The degrees of the relation between recongnition of environment and wise and open dispositions show respectively 0.06 and -0.06 and -0.06. That is to say that when having more affirmative recognition of the working environment, a nursing specialist shows wise but closed disposition of character. This, howerver, didn't mean much statistically. When observing the results mentioned above, it is conspicuous that the nursing specialists, working as substitutes for the nurse at medical institutions of various sizes, get the feeling of being somewhat equal to the nurses and to some extent, fulfill their desire to accomplish their ego; however, as far as professional ability expansion if concerned. they lack wise and open dispositions. Therefore, considiering upon the results of this study, in medical institutions where the work of nursing specialists is regaded equal to that of the nurses, as a medical member who deals with human lives, it is desirable to make the nursing specialists work under the supervision of the nurses and to offer them continuous education to strengthen and improve their natural dispositions.

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Etching Characteristics of Fine Ta Patterns with Electron Cyclotron Resonance Chlorine Plasma

  • Kim, Sang-Hoon;Woo, Sang-Gyun;Ahn, Jin-Ho
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2000.04a
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    • pp.97-102
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    • 2000
  • We have studied etching characteristic of Ta film using Electron Cyclotron Resonance (ECR) etcher system. Microwave source power. RF bias power. and working pressure were varied to investigate the etch Profile. And we have used two step etching method to acquire the goWe have studied etching characteristic of Ta film using Electron Cyclotron Resonance (ECR) etcher system. Microwave source power. RF bias power. and working pressure were varied to investigate the etch Profile. And we have used two step etching method to acquire the good etch profile preventing the microloading effect.od etch profile preventing the microloading effect.

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ORC System Performance Analysis upon R-245fa and Novec 649 (R-245fa 및 NOVEC 649 작동유체에 따른 ORC 시스템 성능 변화)

  • Chang, Hong-Soon;Han, Young-Sub;Song, Yeong-Kil;Kim, Sung-Hyun
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
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    • v.12 no.3
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    • pp.17-23
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    • 2016
  • A test unit for Organic Rankine Cycle (ORC) power generation system was developed and experimentally reviewed the performance of the ORC system. Two different organic fluids (R-245fa & Novec 649) were tested as working fluids for the system. System behavior was measured and analyzed along with the variables, such as temperature, pressure, rpm and shaft power. It is one of the findings that Novec 649 fluid is to be less pressurized than R-245fa in order to up to the heat source (boiler) capacity, that limits the experiment as high as 2 kW in shaft power.

Studies on a Effective Scheme to Obtain High Temperature Working Plasma for MHD Power Generation (MHD발전용 작동 플라즈마를 고온가열하기 위한 효율적 방안에 관한 연구)

  • 김윤식;노창주;김영길;공영경;최춘성
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.1
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    • pp.153-161
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    • 1993
  • Heat transfer processes in the combustion chamber of a pebble bed regenerative heat exchanger for MHD power generation has been analyzed numerically for heating, evacuation argon heating periods individually. The calculated result well explain the measured temperature change at the top of the pebble bed. The analytical result point out that the length of evacution period and the geometry optimization both for the combustion chamber and the heat storage bed are very important factors for the improvement of thermal performance in MHD power generation.

Impact test of a centrifugal pump used in nuclear power plant under aircraft crash scenario

  • Huang, Tao;Chen, Mengmeng;Li, Zhongcheng;Dong, Zhanfa;Zhang, Tiejian;Zhou, Zhiguang
    • Nuclear Engineering and Technology
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    • v.53 no.6
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    • pp.1858-1868
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    • 2021
  • Resisting an accidental impact of large commercial aircrafts is an important aspect of advanced nuclear power plant (NPP) design. Especially after the 9·11 event, some regulations were enacted, which required the design of NPPs should consider the accidental impact of large commercial aircrafts. Normal working of equipment is important for stopping reactor under an impact when an NPP is in operation. However, there is a lack of reliable analysis and research on the impact test of nuclear prototype equipment. Therefore, in order to study the response of the equipment under high acceleration impact, a centrifugal pump is selected as the research object to perform the impact test. A horizontal half-sinusoidal pulse wave was applied to the working pump. The test results show that the horizontal response of the motor and flange is greater compared to other parts, as well as the vertical response of the coupling. The stress response of the pump body support and motor support is high, hence these parts should be considered in the design of the pump. Finally, combined with the damage and stress evaluation results of the pump under different amplitudes, the ultimate impact acceleration that the pump can withstand is given.