• International Journal of Aeronautical and Space Sciences
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• 제13권4호
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• pp.484-490
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• 2012

This paper is devoted to investigate the feasibility of using a medium power ground-based laser to produce a torque on LEO satellites of various shapes. The laser intensity delivered to a satellite is calculated using a simple model of laser propagation in which a standard atmospheric condition and linear atmospheric interaction mechanism is assumed. The laser force is formulated using a geocentric equatorial system in which the Earth is an oblate spheroid. The torque is formulated for a cylindrical satellite, spherical satellites and for satellites of complex shape. The torque algorithm is implemented for some sun synchronous low Earth orbit cubesats. Based on satellites perigee height, the results demonstrate that laser torque affecting on a cubesat has a maximum value in the order of $10^{-9}$ which is comparable with that of solar radiation. However, it has a minimum value in the order of $10^{-10}$ which is comparable with that of gravity gradient. Moreover, the results clarify the dependency of the laser torque on the orbital eccentricity. As the orbit becomes more circular it will experience less torque. So, we can conclude that the ground based laser torque has a significant contribution on the low Earth orbit cubesats. It can be adjusted to obtain the required control torque and it can be used as an active attitude control system for cubesats.

• 한국안전학회지
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• 제21권3호
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• pp.127-136
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• 2006

In 2002 Product Liability Act newly got into effect in Korea so that efforts for Product Safety got a new chance to promote safety standardization. Under the supervision of the Korean Agency for Technology and Standards (ATS) and the Korea Standards Association (KSA), the enterprise titled "Standardization of Product Safety" took the first step in 2000. Thenceforth a lot of standards and guidelines for product safety have been developed. The results of the enterprise were in the type of technical manual as well as report, technical guidelines, and specific technical safety standards. In this paper, the authors narrated those sequential efforts for Product Safety, and introduced the basic concept on which standardization of Product Safety Management System was conducted and individual safety standard has been developed. Based on this systematic concept, a global road-map as well as specific road-maps for developing safety standards in individual industry were supplied. Finally, suggestions for proceeding to the whole risk management system including other risky factors were appended.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 추계학술대회 논문집
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• pp.19-25
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• 2009

본 연구는 변전소(사무실) 설비 환경 개선 차원으로 기존 비상등하에서 조도 부족으로 인한 근무자의 오조작 및 복구 시간 지연을 단축하기 위하여 현재 설치된 등기구의 형태를 백열등에서 형광등으로 대체하였으며, AC/DC 겸용 비상등 및 스위치에 관하 연구하였다. 조도 기준 또한 상시등의 5${\sim}$10[%] 가 아닌 한국 산업 조도 기준(KSA)에 따른 원자력 발전소 조도 기준 및 안전 조명에 의한 조도 기준을 참고로 정확한 변전소 각 실별 조도 기준을 책정하였고 그에 따른 변전소 내선 전기 설계를 표준화하였다. 또한 배터리 용량 산정 기준과 중요도에 따른 각 실별 등기구 설치 수량을 표준화하여 조도 부족으로 인한 2차 사고나 광역 정전 사고로 인한 대형 사고를 방지하고자한다.

• Journal of Power Electronics
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• 제9권5호
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• pp.679-690
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• 2009

The paper presents a new photovoltaic inverter for stand-alone induction motor application. The proposed system is composed of two stages. First stage is for the photovoltaic dc power feeding and second stage is dedicated to the motor-inverter subsystem and control technique. A direct torque control (DTC) with a novel switching strategy for motor torque ripple minimization is introduced. The novel DTC strategy is based on selecting a suitable voltage vector group for motor torque ripple minimization. A three-level voltage source inverter (VSI) is used instead of a two level inverter because the first has more available vectors and lower ripples in the output current and flux than the second, thus it has lower torque ripples. The photovoltaic array and battery bank are sized and the configuration is indicated based on sun-hour methodology. Simulation results show a comparison between three systems; two level VSI with conventional DTC strategy, three level VSI with conventional DTC, and the proposed system that has a novel DTC switching strategy applied to three level VSI. The results show that the proposed system has lower ripples in the current, flux and torque of the motor.

• 산경연구논집
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• 제9권9호
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• pp.45-52
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• 2018

Purpose - This case study is dedicated to the study of the presence of KIA Motors in the Kingdom of Saudi Arabia (KSA) and its market and entry strategies for strategic globalization that allowed the company to establish itself within a conservative and clustered marketplace dominated by American and Japanese international brands. Research Design, data, and methodology - The main information for the case was gathered through an interview and questionnaire from the executives of the KIA Al Jabr, which got the exclusive dealership in Saudi Arabia. Moreover, secondary data were obtained from reliable and authoritative sources such as the Saudi government agency publications, newspapers, international business journals. Other related periodicals based on the results from previous and current studies on similar topics were critically reviewed as well. Results - The findings of this paper show the different business environments of the Saudi market and the importance of various points regarding the company's global entry strategy even if the host market culture is quite different in many ways from other international markets. Conclusions - This case can provide Korean companies interested in the Middle East with insight into market penetration and global strategy, and present various perspectives and implications for global market access as well.

• 한국신뢰성학회지:신뢰성응용연구
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• 제5권2호
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• pp.241-259
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• 2005

The environmental problem is a main subject of the 21C and an environment destruction phenomenon by various kinds of environmental materials is reaching serious level. Nations to be classified as the environmental developed country, are born again environmental rich country. And they earn a large income by trade Every kind environmental resource in an international commercial transaction. Especially, the study that a reliability assessment method to prevent to reliability problem to be happened when the solder lead(lead-free solder), non-cd component, non-bromide component(without the polybrominated biphenyls(PBB) and polybrominated diphenyl ethers(PBDE))and hexavalent chromium(Cr VI) clearance component and mercury-free applied to electronic equipment is progressed. As the result of the study for applying of a reliability assessment technique of lead-free solder that recognized the most of urgent problem at the company, combination accelerated life test could taken by adding and appling the part of a humidity acceleration part to Eyring Model which is proposed by R.E.Thomas. The reliability assessment methods study of PWB clean environmental materials is expected to respond to a reliability elevation and environmental material regulation policy spreading all over the world by beginning form Europe.

• 한국항공우주법학회:학술대회논문집
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• 한국항공우주법학회 2008년도 제40회 국제학술발표대회
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• pp.273-294
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• 2008

Korea now has a rapidly expanding space programme with exploration aspirations. The government is giving priority to the aerospace industry and, to put it on a better footing, enacted an Aerospace Industry Development Promotion Act in 1987, a Space Development Promotion Act in 2005 and a New Space Compensation for Damage Act in 2007. I would like to describe briefly the legislative history, main contents and comment for these three space acts including especially launch licensing, registration of space objects, use of satellite information, astronaut rescue, liability for compensation, third party liability insurance and establishment of committee and plans to assist the Korean space effort. Furthermore author proposed to legislate a draft for the establishment of a new Korean National Space Development Agency (KNSDA: tentative title) to create a similar body to Japan Aerospace Exploration Agency (JAXA), British National Space Centre (BNSC) of UK, French Centre National d'Etudes Spatiales (CNES), German Aerospace Center (DLR), Swedish Space Corporation, China Aerospace Science and Industry Corporation, Indian Space Research Organization (ISRO) as well as the Korean Space Agency (KSA: Tentative title) to create a similar body to Canadian Space Agency, European Space Agency, Russian Space Agency, Italian Space Agency, Israel Space Agency, Indian Department of Space, National Aeronautics and Space Administration (NASA) of USA, China National Space Administration in order to develope efficiently space industry. A call is made for Asian countries to unite and further their space development through a regional space agency.

• 품질경영학회지
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• 제34권4호
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• pp.1-12
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• 2006

The 'KS-QEI' is the quality evaluation model developed both by Korean Standard Association(KSA) and this research team, reflecting the characteristic of KS products' quality and the customers' demand factors. KS-QEI is a general index measuring and announcing KS products' quality excellency through the evaluation of its real user including customers and specialists. This index aimed to evaluate and announce the quality level of KS product annually which was the motivation of products' quality improvement to enterprises and guaranteed the products' reliability to customers. Ultimately, by competing in good faith among domestic enterprises and preparing foundation of continuous research and investment inducement, it was expected to improve the Korean industry's competitive power. This study was intended to develop improved KS-QEI by analysing 2006 research result, to which it had applied ameliorated and enlarged index in 2005. Especially, it established the weight by Analytic Hierarchy Process(AHP), which led to estimate weight mathematically by comparing and evaluating the importance and difficulty by its index. And this paper analyzed the research result by using multi-variate statistical methods.

• Clinical and Experimental Pediatrics
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• 제60권10호
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• pp.327-332
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• 2017

Purpose: Short stature affects approximately 2%-3% of children, representing one of the most frequent disorders for which clinical attention is sought during childhood. Despite assumed genetic heterogeneity, mutations or deletions in the short stature homeobox-containing gene (SHOX ) are frequently detected in subjects with short stature. Idiopathic short stature (ISS) refers to patients with short stature for various unknown reasons. The goal of this study was to screen all the exons of SHOX to identify related mutations. Methods: We screened all the exons of SHOX for mutations analysis in 105 ISS children patients (57 girls and 48 boys) living in Taif governorate, KSA using a direct DNA sequencing method. Height, arm span, and sitting height were recorded, and subischial leg length was calculated. Results: A total of 30 of 105 ISS patients (28%) contained six polymorphic variants in exons 1, 2, 4, and 6. One mutation was found in the DNA domain binding region of exon 4. Three of these polymorphic variants were novel, while the others were reported previously. There were no significant differences in anthropometric measures in ISS patients with and without identifiable polymorphic variants in SHOX. Conclusion: In Saudi Arabia ISS patients, rather than SHOX, it is possible that new genes are involved in longitudinal growth. Additional molecular analysis is required to diagnose and understand the etiology of this disease.

• The Journal of Asian Finance, Economics and Business
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• 제7권8호
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• pp.705-714
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• 2020

This study aims to investigate the main factors that affected the government health expenditures in Gulf Cooperation Council (GCC) countries (Kingdom of Saudi Arabia (KSA), United Arab Emirates (UAE), Oman, Qatar, Bahrain and Kuwait), during the period from 2005 to 2019. The study employs a panel data technique in order to monitor the pooled determinant variables of healthcare expenditures in these countries. The study's results indicate, by using FMOLS approach for panel data, that the average healthcare expenditures per capita in GCC countries have a positive and a significant relationship with the government revenues, the size of the population, and the governments' public debt. The positive and the significant relationships of governments' public debt may be explained even if the governments of the GCC countries suffer from a budget deficit; the GCC countries continue to increase the healthcare expenditure. The study suggests that the policymakers of the GCC countries must take into consideration those variables when they develop their healthcare policies. Also, the GCC countries urgently need to have high levels of foreign exchange reserves to maintain the expected level of spending on the healthcare sector, because their public revenues depend mainly on the oil revenues, which are fluctuating continuously.