• Title/Summary/Keyword: ideal experiment

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Studies on the Diffusion Current of Ideal Streaming Merury Electrode under Gravity (重力下의 理想噴出水銀電極의 擴散電流에 關한 硏究)

  • Kim, Hwang-Am;Jin, Chang-Hi
    • Journal of the Korean Chemical Society
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    • v.5 no.1
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    • pp.80-83
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    • 1961
  • Solution of the diffusion problem applicable to steady state reduction at the ideal streaming mercury electrode are presented, with special attention being given to the influence of stream contraction caused by the gravity. To eliminate the convection occurring in the layer between the streaming mercury and the electrolytic solution, a new method have been invented, in this case the solution being tested was streamed with same velocity of the streaming mercury. Experiment have been made in order to compare the experimental value with the theoretical value and the experimental diffusion current was approached more to the theoretical value than the value obtained by earlier form of the streaming mercury electrode used by Heyrovsky.

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Development of Acid Rain Model Instrument and Its Application in Environmental Education

  • Ma, Chang-Jin;Shin, Eun-Sang
    • Asian Journal of Atmospheric Environment
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    • v.9 no.3
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    • pp.222-227
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    • 2015
  • The environmental education with ideal teaching tools (e.g., a small-scaled experimental kit) is essential for raising the public's, especially student's, awareness of many environmental issues. This study was undertaken to develop a do-it-yourself model instrument of acid rain and estimating its applicability to the environmental education. Our novel model tool consists of a body (17 cm width, 6 cm depth, and 17 cm height), an acid gas injector, acid four rain reservoirs, and a drop supply pump. An alternative model instrument that can be more readily assembled was also suggested. Based on our novel approach, we carried out several model experiments with educatees (i.e., high school and college students, and adults). The results of questionnaires indicated that educatees achieved a very deep understanding of acid rain through an experienced model experiment. A 77 to 89% of educatees experienced the reappearance experiment of acid rain by our model instrument felt that it was very useful as a teaching tool of environmental education.

Iris Image Enhancement for the Recognition of Non-ideal Iris Images

  • Sajjad, Mazhar;Ahn, Chang-Won;Jung, Jin-Woo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.4
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    • pp.1904-1926
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    • 2016
  • Iris recognition for biometric personnel identification has gained much interest owing to the increasing concern with security today. The image quality plays a major role in the performance of iris recognition systems. When capturing an iris image under uncontrolled conditions and dealing with non-cooperative people, the chance of getting non-ideal images is very high owing to poor focus, off-angle, noise, motion blur, occlusion of eyelashes and eyelids, and wearing glasses. In order to improve the accuracy of iris recognition while dealing with non-ideal iris images, we propose a novel algorithm that improves the quality of degraded iris images. First, the iris image is localized properly to obtain accurate iris boundary detection, and then the iris image is normalized to obtain a fixed size. Second, the valid region (iris region) is extracted from the segmented iris image to obtain only the iris region. Third, to get a well-distributed texture image, bilinear interpolation is used on the segmented valid iris gray image. Using contrast-limited adaptive histogram equalization (CLAHE) enhances the low contrast of the resulting interpolated image. The results of CLAHE are further improved by stretching the maximum and minimum values to 0-255 by using histogram-stretching technique. The gray texture information is extracted by 1D Gabor filters while the Hamming distance technique is chosen as a metric for recognition. The NICE-II training dataset taken from UBRIS.v2 was used for the experiment. Results of the proposed method outperformed other methods in terms of equal error rate (EER).

Operation Algorithm and Drive Circuit in Power converter of DC reactor type fault Current Limiter (DC Reactor-Type 한류용 전력변환기의 제어 알고리즘 및 전력 소자 구동 회로)

  • 이승제;서호준;이찬주;고태국
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2002.02a
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    • pp.334-336
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    • 2002
  • This study is concerned with the operation algorithm and power switch drive circuit for DC Reactor Type High-Tc Superconducting Fault Current Limiter (SFCL). In the case of SFCL, Power switching operation algorithm are very important problem. So, this driving will determine the performance of SFCL. In this paper, we provide a simple algorithm and easy drive circuit. Through experiment we found that ideal is right.

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A study on the Program for Substantial Science Education in Secondary Schools Laboratory Experiment-Bared Science Teaching (중등학교 과학교육의 내실화방안에 대한 연구)

  • Cho, Hee-Hyung;Lee, Moon-Won;Cho, Young-Sin;Han, In-Sook
    • Journal of The Korean Association For Science Education
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    • v.9 no.1
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    • pp.75-89
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    • 1989
  • Secondary schools in Korea have been faced with several critical problems with regard to science education. Among them one of the most fundamental problems is associated with laboratory-based science education. There fore as a part of research project for the improvement of science education in secondary schools, this study had its abjectives to inquire into the following areas related to laboratory experiment. ${\circ}$Survey and analysis of theoretical backgrounds for science teaching focused on laboratory experiments. ${\circ}$Status survey of experiment-based science teaching in high schools. ${\circ}$Development of model for improving experiment-based science teaching. In order to fulfill these objectives this study used methods of eiterature review, survey, and interviews. The major finding are as follows : ${\circ}$Some topic for laboratory experiments as oppeared in the textbooks are not appropriate in the light of sience curricular operations in high schools. ${\circ}$In some schools equipments and facilities of school laboratories are for from sufficiency. ${\circ}$Laboratory experiments are not financially supportel for ideal science teach in both middle schools and high schools. These are not on exhaustive list of findings from this study More finding and teaching model for improvement of science education are also described in this paper.

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An Experiment of the Displacement Amplifying Units(DAUs) Driven by the Piezo Actuators (압전소자로 구동되는 변위확대기구에 대한 기초실험)

  • Baek, Chang-Wook;Shin, Jong-Woo;Kim, Yong-Kweon
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.1054-1056
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    • 1993
  • The displacement amplifying units(DAUs) of the flexure hinge mechanism are used to amplify the displacements from the Piezo actuators using the principle of a lever. We fabricate for two step DAUs with the SUS304(stainless steel) and experiment them. The fabricated four DAUs have all the hinges aligned to a straight line, and differ in the first step ideal gain($4{\times}10,\;6{\times}10,\;8{\times}10,\;10{\times}10$). We measure the input and the output displacements to get the real amplifying gain. The resonant frequencies of these DAUs are also measured. The experimental results are compared with those of the theoretical formula and with those of the numerical analyses.

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The Effects of the Models in Ads on Buying Intention, Self-Esteem and Body Satisfaction of College Women (패션 제품 광고 모델이 여대생의 구매의도, 자존심 및 신체 만족에 미치는 효과)

  • Chung Myung-Sun
    • The Research Journal of the Costume Culture
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    • v.14 no.3 s.62
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    • pp.514-527
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    • 2006
  • It can be said that the ultimate goal of advertising is creating consumers' buying intention and buying behavior toward advertised goods. But literature suggests that ads have both intended and unintended consequences, and one of the unintended consequences is that the idealized images of physical attractiveness found in advertising have negative impact on girls' and womens' self-perceptions. Thus, this study, using social comparison theory as a framework, was designed to investigate the influences of the images of models in ads portrayed in TV and fashion magazines on the purchasing intention, self-esteem and body satisfaction of college women. Using an experimental stimulus, a moving picture representing thin and attractive models in the context of advertising fashion goods, two conditions were manipulated and the subjects were placed into one of two groups randomly, the experiment group and the control group. The experiment group only was exposed to the ads portraying highly attractive models. Data were collected from two groups using same questionnaire. The data were analyzed using t-test, two-way ANOVA, and descriptive statistics. The findings were as follows: 1. The thin and attractive image of models in ads on buying intention had significant positive influence on buying intention(p<.05). 2. The thin and attractive image of models in ads had significant negative influences on self-esteem(p<.05). 3. The thin and attractive image of models in ads had significant negative influence on body satisfaction(p<.05). 4. The ideal body internalization had significant negative influences on body satisfaction(p<.05), but interaction effect of model's image and ideal body internalization on body satisfaction was not significant.

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A Study On Design And Pattern Development For The Uniform Of Female Middle-School Students (국내 여중생을 위한 교복 디자인 및 패턴 개발)

  • Han, Wooshin;Choi, Jeongwook
    • Journal of Fashion Business
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    • v.22 no.4
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    • pp.1-19
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    • 2018
  • Unlike other ready-made suits, which are normalized based on aspects like, designs, materials, sewing methods, has to be worn for three years, designing and pattern development of school uniform depends greatly on satisfaction and appearance. Furthermore, school uniform is of importance as many teenagers spend most of their time at school. In the present work, an attempt has been made to suggest ideal school uniform for female middle school students based on their actual uniform conditions and design preferences, so that the demands of artistic aspect, and the requirements of a suitable uniform for a female teenager can be fulfilled. Initially, a survey about the actual wearing condition was held to figure out the actual uniform conditions and design preferences. Based on the result of the survey, two types of school uniform were made with different patterns. Finally, the most ideal school uniform for female middle school students was suggested based on the experiment involving a few aspects such as suitability and functionality. It is conjectured that school uniform survey and investigation, could provide useful information to the school uniform business market.

A Study on Optimal Site Selection for the Artificial Recharge System Installation Using TOPSIS Algorithm

  • Lee, Jae One;Seo, Minho
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.2
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    • pp.161-169
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    • 2016
  • This paper is intended to propose a novel approach to select an optimal site for a small-scaled artificial recharge system installation using TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) with geospatial data. TOPSIS is a MCDM (Multi-Criteria Decision Making) method to choose the preferred one of derived alternatives by calculating the relative closeness to an ideal solution. For applying TOPSIS, in the first, the topographic shape representing optimal recovery efficiency is defined based on a hydraulic model experiment, and then an appropriate surface slope is determined for the security of a self-purification capability with DEM (Digital Elevation Model). In the second phase, the candidate areas are extracted from an alluvial map through a morphology operation, because local alluvium with a lengthy and narrow shape could be satisfied with a primary condition for the optimal site. Thirdly, a shape file over all candidate areas was generated and criteria and their values were assigned according to hydrogeologic attributes. Finally, TOPSIS algorithm was applied to a shape file to place the order preference of candidate sites.

Improvement of PLL Method for Voltage Control of Dynamic Voltage Restorer (동적전압보상기의 전압제어를 위한 PLL 방식의 개선)

  • Kim, Byong-Seob;Choi, Jong-Woo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.5
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    • pp.936-943
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    • 2009
  • Dynamic voltage restorer(DVR) is now more preferable enhancement than other power quality enhancement in industry to reduce the impact of voltage faults, especially voltage sags to sensitive loads. The main controllers for DVR consists of PLL(phase locked loop), compensation voltage calculator and voltage compensator. PLL detects the voltage faults and phase. Compensation voltage calculator calculates the reference voltage from the source voltage and phase. With calculated compensation voltage from PLL, voltage compensator restores the source voltage. If PLL detect ideal phase, compensation voltage calculator calculates ideal compensation voltage. Therefore, PLL for DVR is very important. This paper proposes the new method of PLL in DVR. First, the power circuit of DVR system is analyzed in order to compensate the voltage sags. Based on the analysis, new PLL for improving transient response of DVR is proposed. The proposed method uses band rejection filter(BRF) at q-axis in synchronous flame. In order to calculate compensation voltage in commercial instruments, the PQR theory is used. Proposed PLL method is demonstrated through simulation using Matlab-Simulink and experiment, and by checking load voltage, confirms operation of the DVR