• 한국태양에너지학회 논문집
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• 제30권6호
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• pp.137-143
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• 2010

In this study, the ejector design was modeled using Fluent 6.3 of FVM(Finite Volume Method) CFD(Computational Fluid Dynamics) techniques to resolve the flow dynamics in the ejector. A vacuum system with the ejector has been widely used because of its simple construction and easy maintenance. Ejector is the main part of the desalination system, of which designs determine the efficiency of system. The effects of the ejector was investigated geometry and the operating conditions in the hydraulic characteristics. The ejector consists mainly of a nozzle, suction chamber, mixing tube(throat), diffuser and draft tube. Liquid is supplied to the ejector nozzle, the fast liquid jet produced by the nozzle entrains and the non condensable gas was sucked into the mixing tube. In the present study, the multiphase CFD modeling was carried out to determine the hydrodynamic characteristics of seawater-air ejector. Two-dimensional geometry was considered with the quadrilateral-mashing scheme. The gas suction rate increases with increasing Motive flow circulating rate.

• 반도체디스플레이기술학회지
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• 제14권3호
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• pp.45-50
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• 2015

This paper suggests the sensor-less speed control of PMSM (Permanent Magnet Synchronous Motor) without the position sensor of oil-free air compressor. It estimated d and q axis back electro motive force using Back-EMF (Electro motive Force) observer to control sensor-less speed of PMSM. Also it used the method that tracks the information of rotor position and speed using PLL (Phase Locked Loop) based on estimated d and q axis Back-EMF. The sensor-less speed control of PMSM for oil air compressor application is carried out with the introduced rotor position and speed tracking method. In this paper, the experimental characterization of the sensor-less drive is provided to verify the accuracy of the estimated position and the performance of sensor-less control is analyzed by results obtained from the experiment. Moreover, the potential of PMSM sensor-less drive in industrial application such as compressor drive is also examined.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2007년도 하계학술대회 논문집
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• pp.403-405
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• 2007

This paper presents the over-modulation strategy and indirect vector control drive of NPC type PWM inverter. NPC inverter has three level phase voltage output.It can perform in high voltage through assembling switching components. It has less harmonics and surge voltage stress at motor terminals than the 2 level inverter in same switching frequency through 3 level voltage. The conventional railway vehicle has used the vector control to MI=0.907 and the slip-frequency control from MI=0.907 to six-step mode. The slip-frequency control has bad motive power and slow torque control response. But vector control has good motive power and can instant torque control. In this paper, output voltage is controlled linearly from linear region to six-step mode by using over-modulation strategy. And NPC inverter is used.

• 한국언론정보학보
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• 제65권
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• pp.5-26
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• 2014

본 연구는 전국의 고등학생 및 대학생에 대한 대규모 조사를 통하여 소셜미디어 이용정도 및 이용동기가 교량적/결속적 사회자본 및 참여를 증진시키는 데 얼마나 기여하고 있는지 고찰했다. 특히 소셜미디어를 네트워크 성격에 따라 개방형 네트워크와 폐쇄형 네트워크 서비스로 구분해 분석한 결과, 전자는 교량적 사회자본의 강화에, 후자는 결속적 사회자본의 증진에 기여하는 것으로 나타났다. 소셜미디어이용동기는 교량적/결속적 사회자본 모두에 유의한 영향을 미쳤다. 소셜미디어를 통한 정치 사회적 참여에는 소셜미디어 유형별 이용정도와 이용동기가 모두 유의한 영향을 미쳤다. 결론적으로, 소셜미디어가 사회자본에 미치는 효과는 어떤 성격의 매체를 이용하고 그것을 어떠한 목적으로 이용하는가에 따라 결정된다고 볼 수 있다.

• 한국초등과학교육학회지:초등과학교육
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• 제33권1호
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• pp.82-94
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• 2014

The purpose of this study is to develop teaching program which utilizes emotional intelligence elements as a measure to stimulate the motive and scientific attitude of learners and examine the effect of its application. The target unit for this study is 'world of plants' in the fourth grade of elementary school, and the teaching program is composed of 3 stages including I(encounter with myself), S(encounter with science), and U(encounter with friends). The teaching program is organized in the way to reflect 5 emotional intelligence elements including self-awareness, self-regulation, self-motivation, sympathy, and personal relations properly according to each stage of teaching program. The result of applying this program into actual classrooms is as follows. First, it is proven that the teaching program actually helps improving the motive of learners to study science. The emotional intelligence takes a role of positive motive for thinking, and the learners monitor their emotion and behavior patterns by using a mirror notebook to reduce their anxiety about science. Second, it is proven that the teaching program changes the science related attitude of learners positively. The emotional intelligence elements help the learners to create friendly feeling toward science subject and have a friendly attitude toward science and a sense of expectancy to science class. Third, it is proven that the teaching program contributes to the improvement of learners' science study achievement. The emotional intelligence takes an important role in improving the learners' science study achievement through the role of adjusting and controlling the recognition capability. However, emphasizing the emotional intelligence excessively also has a risk to break the balance between emotion and recognition, so it is considered that the balanced approach should be applied.

• 복식
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• 제63권4호
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• pp.30-43
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• 2013

This study provides suggestions of cultural product design contents by using the cloud-shaped gong in traditional temple culture in order to find a high value-added approach. The research herein is part of cultural design contents projects embedded with the spiritual value and symbolic connotation of temple culture. This would be meaningful to enhance its degree of utilization. This can also be a way to find a strategic alternative to a high value addition of temple stay and dissemination of temple culture. For the research methodology, literature was reviewed over temple stay and Bulgeonsamul. For motive design and development of cultural product design, both Adobe Illustrator CS3 and Adobe Photoshop CS3 were used as computer design program. The template image of cloud-shaped gong for basic motive design was selected from those available at the domestic temples for accurate depiction of its head and body. Finally, samples were adopted from those temples of Gounsa, Songgwangsa, Guinsa, Hwaeomsa, and Naesosa. For each motive, different colors were applied and ten basic motives were practiced in total. By repeating the process for these motives, three types of textile design were prepared. T-shirt designs used a round neckline as basic form, and it was designed for sleeved and sleeveless styles. Apron designs stressed V-neckline and two types were processed: one for the back seam line and the other for side seam line. Pendants were designed with modern and luxurious image so that so that it could be used in various types of accessories. Designs for the bedding applied pattern design of the motives and this was done in a way that gave the images a sense of stability and splendor.

• 산업경영시스템학회지
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• 제41권1호
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• pp.11-23
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• 2018

This paper investigated relationship among internal as well as external motive to receive the ISO 13485 certification, countermeasure to the certification examination, active reception/execution level of the certification, and operational as well as financial performance of the medical device related enterprises in South Korea which received and are maintaining the ISO 13485 certification. SEM (structural equation model) and related analyses using AMOS 21.0 and SPSS 21.0 have been applied to verify the hypotheses of the research. Result of the research showed that internal as well as external motive for certification positively(+) affects active reception/execution level of the certification as well as countermeasure to the certification examination. The reception/execution level of the certification also positively(+) affects on the operational as well as financial performance of the certified enterprises. However, countermeasure to the certification examination was found out to negatively(-) affects the active reception/execution level of the certification and we can interpret that relatively more countermeasure to the certification examination burdens the employees of the enterprise, causing them to be less active on the reception/execution level of the certification. This research found that an enterprise's operational/financial performance improves when an enterprise introduces the ISO 13485 certification standard spontaneously on the purpose of improving its system and the certification system is applied to the enterprise actively, not passively. This research emphasizes the need to recognize the difference of the level of active reception implication among members of an enterprise according to the motive of introduction of the certification system.

• Journal of Korea Trade
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• 제24권7호
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• pp.29-37
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• 2020

Purpose - This paper empirically investigates the relationship between country governance quality and worker remittances from foreign countries. Because remittances can be a source of funds for economic development and smoothing economic crises in developing countries, the related topic has been a concern for policy-makers and academic researchers. This paper divides the motives of remittances into altruistic and investment motives through existing papers, and then considers the governance quality the remittance receiving country as one of the determinants of remittances. Design/methodology - Our empirical model considers whether governance quality can affect the volume of remittances, and uses altruistic and investment factors studied in the literature. To do this, a two-step approach is taken. First, the panel data are examined via pooled OLS, random effects, and Tobit estimation. Second, the paper reduces six governance indicators into one variable, Governance, using the principal component technique (PCA) for a robustness check. Findings - The main findings can be summarized as follows. The negative governance variable in the estimation results shows a lower governance quality that induces workers to send savings to their home countries. This means that a country with poor governance quality seems to have more remittance inflows from abroad. It also reveals that poor governance quality is more relevant to an altruistic motive rather than an investment motive, in general. The positive per capita GDP variable shows the investment motive for developed countries. Originality/value - Existing papers have focused on various factors related to the motives of remittances. However, governance quality effects on remittance inflows have not been fully studied so far. This paper considers governance quality in an estimation equation explicitly as one of the determinants of remittances. This area of study is needed, in theory and empirically, in order to fully understand the relationship between governance and remittances.

• 대한공간정보학회지
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• 제25권1호
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• pp.37-46
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• 2017

최근 우리나라는 사회적 요인에 의한 재난이 빈번하게 발생하고 있다. 어떤 위기가 도시민들을 위협할지 예측하기 어려워 우려가 높아지고 있다. 따라서 본 연구에서는 Python언어 기반 Tweepy 플러그인을 적용하여 트윗 데이터를 취득하는 프로그램을 개발하고, 자연어 처리 후 R Studio프로그램에서 텍스트 클러스터링 분석과 오피니언 마이닝 분석을 통하여 시민들의 건강에 영향을 미치는 성분이 검출된 '옥시'와 시민들에게 많은 공포감을 주었던 '묻지마 범죄'와 같은 사회적 재난에 대해 정신적 충격과 불안감을 평가하였다. 텍스트 클러스터링 분석에서 '옥시' 사건은 '정부의 대처능력이 세월호 사건과의 연관성', '옥시제품의 철수지시에도 여전한 판매' 등이 가장 높은 관심도를 보였다. 그리고 '묻지마 범죄' 사건은 '스크린 도어 사건, 세월호 사건 등 예측 못하는 사건에 대한 정부의 대응, 대책', '강남역, 부산의 범죄가 여성혐오로 인한 것' 등이 가장 높은 관심도를 보였다. 또한, 두 범죄를 비교 분석 하였을 때 묻지마 범죄에 대해 시민 감성도 평균 지수가 11.61%p 더 부정적이라는 것을 알 수 있었다.

• 산경연구논집
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• 제9권1호
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• pp.99-110
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• 2018

Purpose - The purpose of this study is to investigate the relationship among narcissism, usage motives, usage behaviors, satisfaction with and continuance intention to use fashion social media. Research design, data, methodology - A questionnaire survey was used to collect data after conducting a pilot test. Based on the reliability test of the preliminary questionnaire used for the pilot test, the questionnaire was revised. The final questionnaires were administered to 238 fashion social media users and 216 were used for the data analysis. To assess the validity of these measures, exploratory factor analysis and the confirmatory factor analysis were performed. Structural equation modeling analysis were employed for data analysis. Results - Five factors of the usage motivation of fashion social media were extracted: information-seeking, relationship-seeking, practicality-seeking, enjoyment-seeking and self-expression motives. The statistical analysis confirmed the influence of the narcissism tendency on all of the usage motives of fashion social media, three of the fashion social media usage motives influencing information diffusion behavior, and the influence of the information diffusion behavior on users' satisfaction and continuance intention to use fashion social media. Narcissism exerted the highest influences on self-expression motive followed by information-seeking, enjoyment-seeking, relationship-seeking and practicality-seeking motives in order. Factors affecting fashion information diffusion behaviors are practicality-seeking motive, self-expression motive, and relationship-seeking motive. The greater the diffusion of information, the higher the satisfaction with using fashion social media. The consumers with higher satisfaction intended to use fashion social media and share information more frequently. Conclusions - The results indicate that narcissism is an important factor in fashion social media usage motivation. The main motives for narcissistic people to spread information is for the practical purpose at the most, and then to express their personality and style, and to build relationship with others. The satisfaction through active information sharing behaviors seems to play a key role to lead high continuance intention of fashion social media. These implies that marketing strategies to satisfy consumers' narcissism and motives to use social media, and to stimulate the information diffusion behaviors can be used to meet their needs for higher satisfaction with fashion social media.