• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.72-74
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• 2008

전력변환장치들을 이용한 기기의 사용증가로 인해 전력 품질을 저하시키는 요인이 증가하고 있으며 이에 따라 부하 기기의 오동작 및 과열로 인한 전기 안전사고도 증가 하고 있다. 따라서 전력품질 분석기의 올바르고 손쉬운 사용이 요구되고 있다. 본 논문에서는 NI(National Instrument)의 버츄얼 인스트루먼트(Virtual Instrument)기술을 이용하여 개발된 전력품질 분석 프로그램에 대해 논하고자 한다.

• Bulletin of the Korean Chemical Society
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• 제12권3호
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• pp.322-328
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• 1991

We have studied a characterization method of accurate size of spherical particles by fitting experimental light scattering profile to the rigorous theoretical scattering function. An efficient software has been developed for computation of the theoretical scattering function and regression analysis. A light scattering instrument has been built and the necessary data acquisition and analysis are carried out by use of a personal computer with an emphasis on the reduction of analysis and time aiming that this study will be extended toward a development of a practical particle sizing apparatus. The performance of the instrument and the software has been evaluated with latex spheres and found to be satisfactory.

• 대한조선학회논문집
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• 제49권2호
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• pp.189-195
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• 2012

The ice trials of the first Korean icebreaking research vessel "ARAON" were performed at the Arctic Ocean in July-August 2010. The sea ice concentrations of Arctic Ocean were 4/10 to 10/10 and the range of sea ice thickness was roughly 1.0 to 3.5m. In this research, sea ice thickness characteristics at the old ice floes were determined from results of drill hole and apparent conductivity measurements. Especially we measured apparent conductivity using an electromagnetic induction instrument (EM31-MK2) and estimated the sea ice thickness through the empirical equation from Cold Regions Research & Engineering Laboratory, CRREL. The results of estimated sea ice thickness were compared to drill hole measurement results and then, we suggest the new empirical equation to estimate sea ice thickness of single layer type sea ice during the summer season of Arctic Ocean by curve fitting approach to these data.

• 대한간호학회지
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• 제35권6호
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• pp.1091-1100
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• 2005

Purpose: The purpose of this study was to develop an instrument to measure nursing professional values. Method: Forty preliminary items were selected by classifying 223 basic items extracted via a literature study and in-depth interviews of subjects and testing the relevance of their contents. In order to verify the reliability and relevance of the preliminary instrument, data was collected from 504 nurses in 3 general hospitals. Result: As a result of the item analysis, 29 items were selected from a total of 40 items. Five factors were extracted by factor analysis, and the total variance was $51.5\%$. For the explanation of variances by factors, the 1 st factor, 'self-concept of the profession' accounted for $14.8\%$, the 2nd factor, 'social awareness' $12.1\%$, the 3rd factor, 'professionalism of nursing' $9.8\%$, the 4th factor, 'the roles of nursing service' $9.1\%$, and the 5th factor, 'originality of nursing', $5.6\%$. Cronbach's Alpha of those 29 items was .9168, which was high. Conclusion: This paper is meaningful in a way that it developed a tool capable of measuring nursing professional values, which reflects the characteristics of our country. In order to re-verify the relevance and stability of this tool, it is necessary that comparative studies should be conducted.

• 한국안전학회지
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• 제30권4호
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• pp.39-45
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• 2015

This paper deals with development of integrity evaluation instrument for the power line surge protective device. A reliable power supply is an essential element in the developed information and communication society by highly advances in IT technology. However, the lightning incidence also increased with the recent extreme weather events. In Korea, in order to protect the electrical system from lightning surge, SPD(Surge Protective Device) has been used for these past 30 years. However, the method of diagnosing the safety of the SPD in the industry is insufficient. In this paper, SPD integrity evaluation system was composed of a variable DC power source unit, voltage-current sensor and the embedded controller. In order to measure V-I characteristics of MOV, 3 type samples were degraded by impulse current generator. After impulse tests, the varistor voltage of all samples and nonlinearity coefficient were decreased. It confirmed the utility of the developed equipment by this experimental test and the reliability of SPD is expected for surge accident prevention when applied to industrial plant.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2007년도 추계학술대회 논문집
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• pp.291-294
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• 2007

Countries in the world are setting up policies to implement anti-global warning measures to actively cope with the Agreement on Climate Change. Rising problems related to energy and environment prompted research and development efforts to highly efficient electric instrument and environmentally friendly products to secure resources and save energy Korea's high dependency on imported energy and its lack in natural resources make it urgently necessary to develop energy efficient instrument and equipment that can save energy. Every household now uses a transformer, which is very important instrument among others. A variety of technologies to manufacture transformers are currently used along with efforts to develop new materials. Development nit of high efficient transformers is called for by the time and has direct economic impact on suppliers and consumers. In addition, it is desirable to install a transformer that is trustworthy, secure, low on loss, anti-incident capable, small, anti-flammable, environmentally friendly, cost-efficient high-frequency resistant and easy for maintenance. To do this, it is necessary to look deeper into a highly efficient transformer that can save energy. This paper will discuss the types and characteristics of various transformers and propose ways to save energy and raise efficiency tv analyzing a environmentally friendly amorphous transformer.

• 한국환경과학회지
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• 제18권3호
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• pp.255-261
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• 2009

We need water equivalent unit data of snowfall for the purpose of forecast and hydrology related research area. This study developed new method of automatic recording snowfall as weight unit. The instrument designed for measuring weight of snowfall by stain-gauge loadcell. Field test of instrument carried out at Daegwallyeong Obs. Station from 22 Jan. to 22 Feb. 2007. During observation period there is 15.3 cm snow depth and 16.0 mm of accumulated water equivalent depth at Daegwallyeong Obs. Station on 13 to 14 Feb. 2007. But the instrument of this study recorded 22.1 mm of water equivalent depth. It is not easy to explain difference between Daegwallyeong and this study. Because this study is only one case of comparison of snow measurement and there is very little amount of snow observation research. The density of snowfall calculated from 0.09 to $0.15g/cm^3$ from the observation data of 13 to 14 Feb. 2007. There is high relation between radar echo and snowfall amount measured by weight unit. It can supports forecast of snowfall and development of numerical model for forecast.

• 한국간호교육학회지
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• 제21권4호
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• pp.477-489
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• 2015

Purpose: The purpose of this study was to develop an instrument to assess emergency room nurses' knowledge and performance of triage nursing. Methods: The instrument was developed through the stages of conceptual construction, item development, and validity and reliability testing. For the validity and reliability testing, data collected from 48 emergency room nurses using questionnaires was analyzed through descriptive statistics, factor analysis, and reliability coefficients. Results: The knowledge part consisted of 30 items in nine areas, and its reliability was low (KR-20 =0.50). The correct-answer rate was 71.8%. The performance section derived from the factor analysis was composed of two factors with nine items in the triage domain and three factors with 12 items in the non triage domain. The explanatory powers of these factors for the domains were 66.1% and 70.4%, respectively. The overall reliability (Cronbach's ${\alpha}$) was .95, and the reliabilities for the two domains were .88 and .91, respectively. The nurses' mean performance level was 3.2(${\pm}0.45$). Conclusion: The specific contents of the triage nursing work were identified from the developed scale; further research is necessary to in order to develop a scale capable of higher reliability and validity.

• 전자공학회논문지SC
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• 제43권4호
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• pp.60-66
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• 2006

장비를 사용해서 해양자원을 탐사하고 개발하기 위해서 수중초음파 통신은 유용한 수단이 된다. 이러한 응용을 위해서는 정보전달 및 원격제어가 필수적인데, 해양환경에서 다양한 형태의 노이즈가 발생하여 제어의 효율성과 수중통신의 신뢰성이 저하 되고 있다. 그래서 기존의 방법은 하드웨어적인 방법으로 제어정보를 수신하고 이를 반복적으로 기준 정보와 비교하는 방법을 사용하고 있어 제어신뢰성이 중요시되는 시스템에서는 효율성이 떨어지고 있다. 따라서 본 연구에서는 해양환경 변화에 따른 영향이 없이 초음파 신호를 인식할 수 있는 수중 초음파신호 검출성능 향상 알고리듬을 제안하려 한다. 제안하는 알고리듬의 적합성을 시뮬레이션을 통하여 확인하였다.

• 여성건강간호학회지
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• 제10권4호
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• pp.360-367
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• 2004

Purpose: The purpose of this study was to develop an instrument to measure breastfeeding empowerment for the Korean mother, and to test the validity and reliability of the instrument. Method: The items of instruments used was based on literature review. Nineteen item scales were developed with five domains. In order to test reliability and validity of the scale, data was collected from 99 mothers who were within 4weeks, postpatum and 88 mothers who had had children within 1 year. Data was collected between September 2nd and 24th by a self-reported questionnaire. Result: The results were as follows: As a result of factor analysis three times, 19 items were selected from the total of 24 items. Five factors evolved by factor analysis, which explained 65.7% of the total variance. The first factor 'breastfeeding skill' explained 34.1%, the 2nd factor 'group empowerment' 10.6%, the 3rd factor 'breastfeeding will' explained 7.8%, the 4th factor 'social policy empowerment' 7.0%, and the 5th factor 'adherence to exclusive breastfeeding' 6.2%. Cronbach's alpha coefficient of this scale was .8781. Conclusion: The study supports the reliability and validity of the scale. Because the main concept of breastfeeding empowerment was breastfeeding skill, there were distinct differences in the dimensions of breastfeeding empowerment scales.