• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1015_1016
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• 2009

최근 대체조명으로 Power LED가 각광받고 있다. 그러나 반도체 소자인 Power LED의 특성에 의해 기존의 정전압 제어방식으로는 적절한 제어에 어려움이 있다. 이러한 문제의 해결책으로 본 연구에서는 Power LED를 MCU(Micro Controller Unit)를 이용한 디지털 정전류 제어방법에 대하여 서술하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1529-1531
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• 2008

Since the discovery over a decade ago, carbon nanotubes (CNTs) have been attracting considerable attentions both from scientists and engineers. Because of the excellent field emission properties, such as high aspect ratio, extremely small diameter, and high emission current, CNTs become a potential candidate as field emitter for field emission display (FED) and lighting (FEL) as backlight for LCD. Due to the exceptional physical properties, such as superior thermal and electrical conductivities, as well as high stiffness and strength, the CNT-based composites can be as light-weight heat-sink or thermal spreader materials used for power electronic devices, such as power LED for general illumination. The CNTs for above applications will be reviewed, and related materials and devices will be demonstrated in this paper.

• Journal of Oriental Neuropsychiatry
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• v.26 no.4
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• pp.407-416
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• 2015

Objectives: This study was performed to evaluate the reliability and validity of the instrument on pattern identifications for depression. Methods: Two assessors carried out an evaluation about the instrument on pattern identifications for depression, targeting 201 participants, who after taking the HAM-D score over 12 or under 7 twice. Results: Inter-assessor reliability was higher than intra-assessor reliability in a reliability analysis about classification of pattern identification evaluated by the instrument on pattern identifications for depression. Reliability of intra-assessor and inter-assessor showed a moderate to strong agreement when reliability analysis about classification score of the pattern identification had been performed. Reliability analysis to evaluate the validity of the instrument on pattern identifications for depression showed moderate agreement. Conclusions: The results reveal that reliability analysis of the instrument on pattern identifications for depression showed an over moderate agreement and validity analysis represented a positive correlation.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.26 no.1
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• pp.12-22
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• 2019

Purpose: This study was done to verify the self-directed learning instrument (SDLI) developed to measure self-directed learning ability in nursing students. Methods: The participants for the study were 425 nursing college students. Their self-directed learning was verified using self-reports and results through questionnaires. SDLI was translated into Korean through translation/reverse translation process and its content validity verified by five experts. The validity of the instrument was verified through item analysis, exploratory factor analysis, and confirmatory factor analysis. Reliability verification was analyzed using internal consistency reliability. Results: Four factors were identified through exploratory factor analysis and 20 items of the original instrument were found to be valid. In the confirmatory factor analysis, the validity of the instrument was verified as the model was valid. The internal consistency reliability was also acceptable and SDLI was found to be an applicable instrument. Conclusion: SDLI has been developed and verified by selecting nursing students as participants for the study. Use if SDLI is expected to improve the quality of self-directed learning in nursing education and to be used in future nursing research.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.40.1-40.1
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• 2020

The Korea Astronomy and Space Science Institute is participating as a South Korean partner in the Commercial Lunar Payload Services (CLPS)of NASA. In response, the Korea Astronomy and Space Science Institute is currently conducting basic research for the development of four candidate instrument payloads. The magnetic field instrument is one of them and it's scientific mission objective is the moon's surface magnetic field investigation. Therefore, the development requirement of the lunar surface magnetic field instrument were derived and the initial conceptual design was started. The magnetic field instrument has a 1.2 meter boom which has two three-axis fluxgate magnetometer sensors and one gyro sensor to get a attitude information of the boom. The concept of measuring the lunar surface magnetic field will carry out using multiple sensors by placing semiconductor type magnetic field sensors inside the electric box including boom mounted fluxgate sensors. In order to overcome the very short development period, we will use the KPLO (Korean Lunar Pathfinder Orbiter) magnetometer design and parts to improve reliabilities for this instrument. In this presentation, we introduce the instrument requirements and conceptual design for the Lunar surface magnetic field instruments.

• Korean Journal of Adult Nursing
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• v.12 no.4
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• pp.741-757
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• 2000

This study was undertaken to develop an instrument to be used for measuring the concept of quality of life of Korean patients with cancer multidimensionary and correctly. It can contribute in holistic nursing care for Korean cancer patients and also provide and validate basic data to help oncology nurses measure the outcome of nursing intervention correctly. To develop this instrument, the researchers first estabilished a conceptual framework based on the results of qualitative data analysis and indepth interview method Development of the scale was conducted using a method in which 31 items were assessed by subjects' self report using linear analogue scales. The subjects were 79 D.M. patients, 103 patients with acute illness, and 91 cancer patients residing in Busan, Korea. Data were collected during the period from July, 24 to August 14, 2000. This instrument consisted of 31 items with a self report scale. This instrument covered 4 dimensions of cancer patients : 1) physical wellbeing 2) psychological wellbeing 3) social wellbeing and 4)spiritual wellbeing. Each item had a possible score of 10. The reliability of the scale was tested with Cronbach's alpha. Validity was evaluated by examining the relationships of this scale, Youn's Quality of Life Questionnare scores and the Simple Quality of Life scale. Two separate runs of multiple regression were used to predict scores on the Simple Quality of Life measurement. Further validation was obtained by examining the correlation between the instrument subscores and Youn's Quality of Life measurement subscore for convergence of this scale. Examination of the discriminant. power of the instrument was done using ANOVA test. The results are summarized as follows: 1. The reliability of the instrument for the quality of life was 0.8321(Cronbach's alpha.), physical wellbeing dimension 0.6343, psychological wellbeing dimension 0.6501, spiritual wellbeing dimension 0.5883. 2. This instrument had a high correlation with Youn's Quality of Life measurement(r= 0.636) in cancer patients, whereas it had a low correlation with Simple Quality of Life measurement(r=0.455) in cancer patients. In the D.M. patients, the instrument correlated with both the Youn's Quality of Life measurement and Simple Quality of life measurement(r=0.313, r= 0.407) and in the acute stage patients, the instrument had no correlation. 3. Multiple regression of individual items on the Simple Quality of Life scores accounted for 56.8% of the variance in the Simple Quality of Life measurement, whereas, Youn's Quality of Life measurement scores accounts for 31.7%. 4. The correlations collected from the three group had the same patterns of variations but especially the instrument developed in this study had higher disciminant power than that of Youn's Quality of Life Measurement.

• Journal of Oriental Neuropsychiatry
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• v.24 no.4
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• pp.331-342
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• 2013

Objectives: The purpose of this study is to examine the validity, the test-retest reliability and to provide guidelines for the Instrument on Pattern Identifications for Hwa-byung. Methods: Participants are 97 patients with Hwa-byung who were diagnosed by Hwa-Byung Diagnostic Interview Schedule. Participants were tested twice within one week. Results: The test-retest reliability of the Instrument on Pattern Identifications for Hwa-byung was examined for 97 patients and calculated to be 0.3146. The reliability of the Instrument on Pattern Identifications for Hwa-byung was 0.605 with a difference of 5% or more for the first and the second. To confirm the validity of the Instrument on Pattern Identifications for Hwa-byung, we analyzed the relevance between symptoms, Pattern Identifications that belong to the group and other Pattern Identifications that do not belong. Conclusions: It can be diagnosed in the first pattern identification by the Instrument of Pattern Identifications for Hwa-byung when there is a difference of 5% or more in the first and second pattern identification. Based on this result, we derived an Instrument for Pattern Identifications of Hwa-byung that has been further modified through additional studies.

• Journal of The Korean Association For Science Education
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• v.41 no.6
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• pp.533-542
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• 2021

This study aims to develop an instrument for measuring high school students' action competence on climate change (ACoCC). The instrument is defined as the construct comprised of seven factors and thirty-five items and takes approximately 15 minutes to fill out. A panel of experts and students' content validation were undertaken to modify the items. Five hundred and twenty-eight first and second graders in Korean high schools participated in the instrument survey. To assess the reliability and validity of ACoCC instrument, item analysis (mean, skewness, kurtosis, item-total correlation), internal consistency estimate, and confirmatory factor analysis were used. It was appropriate to use the 7-dimensional ACoCC instrument (knowledge about climate change, climate change sensibility, reflection, communication, integrated thinking, willingness, decision making), with 35 items for high school students. The following instrument was self-report given in the 5-point Likert scale (1=strongly disagree, 2=disagree, 3=neutral, 4=agree, 5=strongly agree). The internal consistency coefficient was shown as a whole was shown as 0.953, and the subscale's internal consistency coefficient ranged from 0.786 to 0.862.

• Journal of Korean Elementary Science Education
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• v.24 no.3
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• pp.226-235
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• 2005

In this study, we applied the elementary performance assessment instrument on 575 theme in science instruction which it had been developed on the previous study. Sixty-seven elementary students participated in this study and were assigned into two groups: One was assigned to an experimental group since they were taught with the instrument (N=32) and the other was assigned to the comparison group since they followed teachers guide of 7th Korean National Curriculum (N=35). Prior to and after teaching, tests on the science attitude, science process skill, and science knowledge domains were administrated. The results were analyzed quantitatively. Further, we also investigated students recognition about the instrument and the science class qualitatively according to the instrument. The results showed that there were statistically significant improvements on science process skills and aspects of the understanding of science knowledge. Many students were aware of them positively as well. However, a few problems, including too many amounts of writing and difficulties in communication with one another, were appeared.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.83-89
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• 2004

The electronic distance measurement instrument, first introduced in the 1950s has, since those early days, undergone continual refinement. Rapid advances in related technologies have provided lighter, smaller and more precise equipment. Understanding for the principle, the standardized observation technique and the precision of EDM instrument is mostly important to improve the quality and the reliability of by-product in the field of engineering and industrial surveying. Simple and accurate calibration is regularly and periodically necessary to maintenance the precision of EDM instrument. This paper describes the calculated example of zero error and scale error as a correction of EDM by applying the least square method to baseline observations. Here we deals also with the testing criteria for precision instrument testing according to different types of EDM instruments.