• 제목/요약/키워드: Research Tends

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A Economic feasibility of Superconducting Fault Current Limiter in Korean Power System (초전도한류기의 계통도입을 위한 경제적 타당성 검토)

  • Kim Jong Yul;Lee Seong Ryul;Yoon Jae Young
    • Proceedings of the KIEE Conference
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    • 대한전기학회 2004년도 하계학술대회 논문집 A
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    • pp.421-423
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    • 2004
  • As power system grows more complex and power demands increase, the fault current tends to gradually increase. In the near future, the fault current will exceed a circuit breaker rating for some substations, which is an especially important issue in the Seoul metropolitan area because of its highly meshed configuration. Currently, the Korean power system is regulated by changing the 154kV system configuration from a loop connection to a radial system, by splitting the bus where load balance can be achieved, and by upgrading the circuit breaker rating. A development project applying 154kV Superconducting Fault Current Limiter(SFCL) to 154kV transmission systems is proceeding with implementation slated for after 2010. In this paper, the expected price of SFCL in order to assure the economic feasibility is evaluated comparing with upgrading cost of ciui.1 breakers. The results show that the SFCL should be developed under seven times of price of circuit breaker to be competitive against upgrading circuit breakers.

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Effect of Asymmetric Hot Rolling on the Texture Evolution of Fe-3%Si Steel

  • Na, Tae-Wook;Park, Hyung-Ki;Park, Chang-Soo;Joo, Hyung-Don;Park, Jong-Tae;Han, Heung Nam;Hwang, Nong-Moon
    • Metals and materials international
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    • 제24권6호
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    • pp.1369-1375
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    • 2018
  • In Fe-3%Si steel, the hot rolling process affects not only the hot rolling texture but also the primary recrystallization texture. Here, the effect of asymmetric hot rolling was studied by comparing the difference in the texture evolved between asymmetric and symmetric hot rolling. The effect of asymmetric hot rolling on the texture of primary recrystallized Fe-3%Si steel was also studied. The symmetric hot rolling of Fe-3%Si steel produces a rotated cube texture at the center but Goss and copper textures near the surface. Asymmetric hot rolling tends to produce Goss and copper textures even at the center like the texture near the surface. After primary recrystallization, the dominant texture at the center changes from {001} <210> to {111} <112> and the new texture has a higher fraction of the grains which make the low energy boundary with Goss grains than that of symmetric hot rolling.

The Effect of Compensation and Career on Turnover Intention: Evidence from Indonesia

  • VIZANO, Nico Alexander;SUTAWIDJAYA, Ahmad Hidayat;ENDRI, Endri
    • The Journal of Asian Finance, Economics and Business
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    • 제8권1호
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    • pp.471-478
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    • 2021
  • This study aims to investigate the determinants of turnover intention among company managers in Indonesia. Based on the literature, this research hypothesizes that job satisfaction is a mediator in the relationship between compensation, career and turnover intention of companies in Indonesia. Respondents as research samples are grouped into middle managers from two industries, namely, manufacturing and services. A total of 215 questionnaires were returned from middle managers. Data analysis used Structural Equation Model - Linear Structural Relationship (SEM LISREL). The research results prove that compensation and career have a positive effect on job satisfaction. Compensation, career, and job satisfaction have a negative impact on turnover intention. Compensation is known to be one of the motivating drivers of workers around the world. From this study it can be said that, if middle manager teachers are well compensated, they will be encouraged, persuaded and will have positive feelings toward their work, and this will result in staying put. It works also with career and job satisfaction. If both variables are considered carefully, intention to move tends to be low. These findings provide new insights into the field of international human resources in developing multinational companies and service businesses.

A Study on the Experimental Trend Analysis of Underwater Noise Factors in Compressed Water System of the Linear Pump Type (선형펌프방식 압축수 시스템의 실험적 수중소음인자별 경향분석 연구)

  • Yi, Jong-ju;Ahn, Kang-su;Sur, Jong-mu
    • Journal of the Korea Institute of Military Science and Technology
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    • 제24권2호
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    • pp.228-236
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    • 2021
  • In order to understand the underwater noise source factor of the linear pump type forced ejection system, a reduced-model compressed water experiment device was developed. The reduced-model compressed water experiment device consists of a reverberation tank, a linear pump type forced ejection device, and an underwater vehicle. The underwater noise source was selected from the hydraulic ram moving speed, the hydraulic ram/piston pipe spacing, the ejection pipe inlet/water ram area ratio, and the number of water ram inlets. The underwater vehicle was ejected into the reverberation tank by the device. The source level was derived from the measured sound pressure. The source level tends to increase as the hydraulic ram/piston tube spacing and the hydraulic ram moving speed increase. The source level tended to increase as the area ratio was increased, but the level was weak. The number of water ram inlet did not affect the source level.

A Study on Korean Public Diplomacy of Appropriate Technology (한국의 적정 과학기술 공공외교 현황)

  • Baek, Woonho;Shin, Jin;Koo, Ki-kwan;Jung, Jihoo;Choi, Sangjin
    • Journal of Appropriate Technology
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    • 제6권2호
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    • pp.103-114
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    • 2020
  • Appropriate technology could be viewed in light of the framework of public diplomacy in which different countries and peoples interact with the environment and demand of residents in developing countries abroad. Korea has been relatively recently participating in public diplomacy since the effectuation of public diplomacy law in 2016, and tends to focus on cultural areas such as the Korean Wave. In this regard, this study compares the current state of public diplomacy in science and technology with major foreign countries and consider Korea's strengths, potential for development and evaluation management. The framework of public diplomacy may provide an opportunity to seek systemic cooperation in appropriate technology.

Numerical investigation of glass windows under near-field blast

  • Chiara Bedon;Damijan Markovic;Vasilis Karlos;Martin Larcher
    • Coupled systems mechanics
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    • 제12권2호
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    • pp.167-181
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    • 2023
  • The determination of the blast protection level and the corresponding minimum load-bearing capacity for a laminated glass (LG) window is of crucial importance for safety and security design purposes. In this paper, the focus is given to the window response under near-field blast loading, i.e., where relatively small explosives would be activated close to the target, representative of attack scenarios using small commercial drones. In general, the assessment of the load-bearing capacity of a window is based on complex and expensive experiments, which can be conducted for a small number of configurations. On the other hand, nowadays, validated numerical simulations tools based on the Finite Element Method (FEM) are available to partially substitute the physical tests for the assessment of the performance of various LG systems, especially for the far-field blast loading. However, very little literature is available on the LG window performance under near-field blast loads, which differs from far-field situations in two points: i) the duration of the load is very short, since the blast wavelength tends to increase with the distance and ii) the load distribution is not uniform over the window surface, as opposed to the almost plane wave configuration for far-field configurations. Therefore, the current study focuses on the performance assessment and structural behaviour of LG windows under near-field blasts. Typical behavioural trends are investigated, by taking into account possible relevant damage mechanisms in the LG window components, while size effects for target LG windows are also addressed under a multitude of blast loading configurations.

Informal Support as an Influential Factor in Elderly Women′s Health: The Importance of Same-Sex Friendship in US

  • Kim, Jeoung-Hee
    • Korean Journal of Health Education and Promotion
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    • 제1권1호
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    • pp.59-73
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    • 1999
  • It is known that the role of informal support for elderly women is critical to their physical and mental health, adjustment in old age, and their overall life satisfaction. Elderly women's situation such as social losses, widowhood, living alone, and geographic relocation etc. may result in a need for more informal supports for elderly women's health than ever before. Particularly, women's same-sex friendships were rated higher for overall quality, intimacy, enjoyment, and nurturance. Unlike a generally accepted notion that later life for women is a time of isolation and loneliness, elderly women tend to maintain and reestablish their friendship regardless their marital status and living situation. Although studies on informal support for elderly women were inconclusive in many ways, elderly women's friendship tends to be stable despite of changing health status and life events. The relative importance between daughters and friends was also controversial. This study suggests that more research with reliable measurements is necessary for the practical prevention and intervention program of elderly women's health on this issue.

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Modeling Of Critical Flux Conditions In Crossflow Microfiltration

  • Kim, Su-han;Park, Hee-kyung
    • Water Engineering Research
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    • 제1권2호
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    • pp.119-127
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    • 2000
  • In the process of crossflow microfiltration, a deposit of cake layer tends to form on the membrane, which usually controls the performance of filtration. It is found, however, that there exist a condition under which no deposit of cake layer is made. This condition is called the sub-critical flux condition, and the critical flux here means a flux below which a decline of flux with time due to the deposit of cake layer does not occur. In order to study the characteristics of the critical flux, a numerical model is developed to predict the critical flux condition, and is verified with experimental results. For development of the model, the concept of effective particle diameter is introduced to find a representative size of various particles in relation to diffusive properties of particles. The model is found to be in good match with the experimental results. The findings from the use of the model include that the critical flux condition is determined by the effective particle diameter and the ratio of initial permeate flux to crossflow velocity.

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A Fundamental Study on Vibrated Crushed-stone Pile for the Improvement of Liquefaction Resistance (액상화 방지를 위한 진동쇄석말뚝에 관한 기초적 연구)

  • 천병식
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 한국지진공학회 2000년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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    • pp.105-111
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    • 2000
  • If a saturate sand is subjected to ground vibrations it tends to compact and decrease in volume. if drainage is unable to occur the tendency to decrease in volume results in an increase in pore water pressure and if the pore water pressure build up to the point at which it is equal to the overburden pressure the effective stress becomes zero the sand loses its strength completely. This phenomenon is called "Liquefaction" It is associated primarily but not exclusively with saturated cohesion soils. The attention and study on liquefaction have been growing since the earthquake in Niigita Japan in 1964. Many researchers on liquefaction effect have been carried out in many countries under the potential influence of earthquake including Japan. However little research on liquefaction has been reported in Korea because Korea has been considered to be safe from earthquake. The term "liquefaction" is only known among geotechnical engineers,. In this paper overview of liquefaction and the evaluation on the applicability of vibrated crushed-stone pile as a liquefaction prevention method are presented.ethod are presented.

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Pastiche in Fashion by Bodily Deformation (몸의 왜곡을 통한 혼성모방)

  • Yim, Eun-Hyuk
    • Journal of the Korean Society of Clothing and Textiles
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    • 제33권4호
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    • pp.511-518
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    • 2009
  • Freed from its traditional confinement to the human body, postmodernism in fashion exposes the defectiveness of body and abstracts from the body under. Deformation of the body denotes the break away from the idealized and standardized body for mass productions. It tends to experiment with extreme exaggeration in form, refusing to subscribe to the traditional values that build on the balance and symmetry of the body. Bodily deformation carried out historical and cultural pastiche opposes the sartorial convention and symbolism which results in the discord between signifiant and $signifi{\acute{e}}$ of clothing. As a type of intimate architecture, fashion always mediates the dialogue between clothes and body, or fashion and figure. My study suggests a framework to analyze bodily deformation as pastiche, focusing on the relationship between clothes and the body. In order to inquire the deformation of the body in fashion, my study examines subjects of the fashion collections of the turn of the 21st century, using the method of literature research and content analysis.