• 한국통신학회논문지
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• 제30권5C호
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• pp.305-312
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• 2005

음악인식에 주로 사용되는 세 가지 알고리즘의 성능을 비교하였다. 다양한 분류알고리즘을 소개하고 그 중 베이지안법, 최근접이웃법과 k-최근접이웃법을 이용하여 악기를 분류하였다. 악기 샘플파일에서 영교차율, 평균, 분산, 평균피크레벨의 4가지 특성값을 추출하여 분류시스템의 데이터로 사용하였다. 사용된 악기 샘플은 바이올린, 바로크 바이올린, 바로크 첼로이다. 실험결과 최근접이웃 알고리즘이 악기 분류에 있어서 가장 좋은 성능을 보여 주었다. 최근접이웃 알고리즘은 단순하면서도 빠른 계산결과를 보여 악기 분류에 적절한 알고리즘으로 판단되었다.

• 한국초등과학교육학회지:초등과학교육
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• 제23권2호
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• pp.159-171
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• 2004

Understanding the nature of science is being emphasized recently among the major goals of science education. The nature of science is concerned with aims of scientific work, the status and nature of scientific knowledge, and science as societal institution. This is a review on how to investigate the pupils' ideas about the nature of science, which was suggested by Driver et al. in their book 'Young people's images of science (1996)'. The purpose of this review is to consider the methodological problems of investigating the pupils' ideas about the nature of science, and to get the implications of developing the instruments about it. The instruments, developed by Driver et al., are described as a model and their suggestions are surveyed. Several hints are given this article to develop the similar instruments.

• 한국컴퓨터정보학회논문지
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• 제22권1호
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• pp.77-87
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• 2017

In this paper, we propose an analysis of the sound source of virtual orchestral music in detail by using the production technology of sampling and playback, and technical experiments and verification for the most advanced Hollywood Library series of timbre and the timbre production and control technology of Vienna instrument Pro and other softwares, to find their solutions and come up with the best timbre production method for orchestral music from the perspective of the specific design ideas of the productions of virtual orchestral instruments. The so-called virtual orchestral instruments are non-real orchestral instruments, which are based on the imitation of timbre of real orchestral instruments, processed and synthesized through the scientific and technological means, and produced by the use of electronic equipments or computers. The study of virtual timbre production technology is very important, and it is like the study of composers' creative techniques. Not only scientific and advanced timbre production methods can be obtained from the study, but also new ways of future timbre production are expected to be explored.

• Applied Microscopy
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• 제45권3호
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• pp.131-134
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• 2015

Here we show how by processing energy dispersive X-ray spectrometry (EDS) data obtained using highly sensitive, new generation EDS detectors in the AZtec LayerProbe software we can obtain data of sufficiently high quality to non-destructively measure the number of layers in two-dimensional (2D) $MoS_2$ and $MoS_2/WSe_2$ and thereby enable the characterization of working devices based on 2D materials. We compare the thickness measurements with EDS to results from atomic force microscopy measurements. We also show how we can use electron backscatter diffraction (EBSD) to address fabrication challenges of 2D materials. Results from EBSD analysis of individual flakes of exfoliated $MoS_2$ obtained using the Nordlys Nano detector are shown to aid a better understanding of the exfoliation process which is still widely used to produce 2D materials for research purposes.

• 한국정밀공학회지
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• 제21권12호
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• pp.7-12
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• 2004

• 대한예방한의학회지
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• 제17권3호
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• pp.129-141
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• 2013

Objectives : Anorexia is the primary symptom impinging cancer patients' Quality of Life. It is usually accompanied by gastrointestinal symptoms(GI symptoms). Thus, to measure anorexia symptom precisely, assessing anorexia and GI symptoms together is recommended. This study was designed to analyze cancer-related anorexia assessment tools, extract GI symptoms included in these tools and investigate usefulness of instruments in clinical trials. Methods : Instruments were selected by searching PubMed, PROQOLID database. We analyzed instruments by number of items, assessment method, type of question, GI symptoms. Results : 9 instruments were selected to assess cancer-related anorexia symptom. Most tools adopt Likert scale as response scale and 'during past week' as recall period. Assessment method of all 9 instruments is the self-administration. Questions measuring anorexia are able to be sorted into 3 forms (frequency, severeness, distress of anorexia symptom). Among the GI symptoms, nausea is included in all 9 instruments. In clinical trials of cancer-related anorexia, Edmonton Symptom Assessment Scale(ESAS) and Functional Assessment of Anorexia/Cachexia Therapy Questionnaire(FAACT) were selected as endpoint measure. Conclusions : The result showed that FAACT is the only specialized tool to assess cancer-related anorexia. To measure cancer-related anorexia precisely, the need to develop new instrument exists.

• Smart Structures and Systems
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• 제16권4호
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• pp.579-591
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• 2015

This paper investigates a magnetoelectric (ME) vibration energy harvester that can scavenge energy in arbitrary directions in a plane as well as wide working bandwidth. In this harvester, a circular cross-section cantilever rod is adopted to extract the external vibration energy due to the capability of it's free end oscillating in arbitrary in-plane directions. And permanent magnets are fixed to the free end of the cantilever rod, causing it to experience a non-linear force as it moves with respect to stationary ME transducers and magnets. The magnetically coupled cantilever rod exhibits a nonlinear and two-mode motion, and responds to vibration over a much broader frequency range than a standard cantilever. The effects of the magnetic field distribution and the magnetic force on the harvester's voltage response are investigated with the aim to obtain the optimal vibration energy harvesting performances. A prototype harvester was fabricated and experimentally tested, and the experimental results verified that the harvester can extract energy from arbitrary in-plane directions, and had maximum bandwidth of 5.5 Hz, and output power of 0.13 mW at an acceleration of 0.6 g (with $g=9.8ms^{-2}$).

• 한국과학교육학회지
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• 제20권1호
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• pp.1-11
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• 2000

본 연구에서는 초 중등 학생들의 눈금 읽기 능력과 측정도구의 용도 및 단위에 대한 개념을 조사했다. 초등학생 72명, 중1 학생 69명, 중3 학생 80명의 학생을 대상으로 수행 평가 및 지필 평가를 실시했다. 눈금읽기 능력을 평가하기 위해서 개별 수행 평가를 실시했는데, 학생 개개인은 서류 봉투의 가로 세로 길이, 물의 온도, 물의 부피 등을 실험실에서 주로 사용하는 주어진 측정 도구를 사용하여 측정했다. 측정 도구 및 단위와 관련된 개념을 평가하기 위해서는 그림과 사진이 그려진 질문지를 사용했다. 눈금 읽기 능력 면에서 각 학년마다 적지 않은 측정오차를 내는 학생이 있음이 드러났으며 특히 질량이나 부피 측정의 경우 그 수가 더욱 증가했다. 측정 도구에 대한 학생의 개념 조사 결과 학생들은 물리량 개념이 정확하지가 않아 측정 도구가 측정할 수 있는 물리량을 제대로 지적하지 못했다. 또한 단위에 대해서도 혼동이 있어서 특히 질량, 무게, 부피나 힘의 단위 등을 어려워하고 있음을 알 수 있었다.

• Journal of Astronomy and Space Sciences
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• 제34권1호
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• pp.45-54
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• 2017

This study examines the scale unique instruments used for astronomical observation during the Joseon dynasty. The Small Simplified Armillary Sphere (小簡儀, So-ganui) and the Sun-and-Stars Time-Determining Instrument (日星定時儀, Ilseong-jeongsi-ui) are minimized astronomical instruments, which can be characterized, respectively, as an observational instrument and a clock, and were influenced by the Simplified Armilla (簡儀, Jianyi) of the Yuan dynasty. These two instruments were equipped with several rings, and the rings of one were similar both in size and in scale to those of the other. Using the classic method of drawing the scale on the circumference of a ring, we analyze the scales of the Small Simplified Armillary Sphere and the Sun-and-Stars Time-Determining Instrument. Like the scale feature of the Simplified Armilla, we find that these two instruments selected the specific circumference which can be drawn by two kinds of scales. If Joseon's astronomical instruments is applied by the dual scale drawing on one circumference, we suggest that 3.14 was used as the ratio of the circumference of circle, not 3 like China, when the ring's size was calculated in that time. From the size of Hundred-interval disk of the extant Simplified Sundial in Korea, we make a conclusion that the three rings' diameter of the Sun-and-Stars Time-Determining Instrument described in the Sejiong Sillok (世宗實錄, Veritable Records of the King Sejong) refers to that of the middle circle of every ring, not the outer circle. As analyzing the degree of 28 lunar lodges (lunar mansions) in the equator written by Chiljeongsan-naepyeon (七政算內篇, the Inner Volume of Calculation of the Motions of the Seven Celestial Determinants), we also obtain the result that the scale of the Celestial-circumference-degree in the Small Simplified Armillary Sphere was made with a scale error about 0.1 du in root mean square (RMS).

• Restorative Dentistry and Endodontics
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• 제19권2호
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• pp.499-512
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• 1994

The purpose of this study was to evaluate the microleakage electrochemically using different retrograde filling materials, different root resection angle, and different cavity preparation instruments. 104 extracted single-rooted teeth were selected for this study. 100 teeth were used as experimental groups and four was used as controls. Anatomical crowns were resected, root canals were prepared, and the apical 2 mm of roots were removed. The experimental roots were randomly divided into five equal groups. Experimental groups : Group 1. no bevel, cavity preparation with ultrasonic instruments, amalgam filling Group 2. no bevel, cavity preparation with ultrasonic instruments, SuperEBA cement filling Group 3. no bevel, cavity preparation with ultrasonic instruments, desiccated ZOE filling Group 4. $45^{\circ}$ bevel, cavity preparation with ultrasonic instruments, amalgam filling Group 5. no bevel, cavity preparation with conventional bur, amalgam filling Microleakage was measured once a day for 30 days using electrochemical method and were analyzed statistically. The results were as follows : 1. The group with Super EBA cement filling showed the least marginal leakage from second to fourth day(p<0.05), there was no significant difference between the group with amalgam filling during eighth to eighteenth day(p>0.05), but after the nineteenth day here was a higher marginal leakage than the group with amalgam filling(p<0.05). 2. The group with desiccated ZOE filling demostrated that the highest marginal leakage, started on the eighth day(p<0.05). 3. The group using ultrasonic instrument showed lower marginal leakage than the group using bur until the nineteenth day(p<0.05), but there was no significant differnce with the group using bur after twentythird day(p>0.05). 4. The group without bevel showed lower marginal leakage than the group with bevel (p<0.05). 5. Whether bevel or nor had much more effect on marginal leakage than with cavity perparation instrument when the cavity was retrogrdefilled with amalgam(stepwise regression).