• Journal of Electrical Engineering and Technology
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• 제7권2호
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• pp.221-224
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• 2012

We propose a Readout Integrated Circuit (ROIC), which applies a fixed current bias sensing method to the input stage in order to simplify the circuit structure and the infrared sensor characteristic control. For the sample-and-hold stage to display and control a signal detected by the infrared sensor using a two-dimensional (2D) focal plane array, a differential delta sampling (DDS) circuit is proposed, which effectively removes the FPN. In addition, the output characteristic is improved to have wider bandwidth and higher gain by applying a two-stage variable gain amplifier (VGA). The output characteristic of the proposed device was 23.91 mV/$^{\circ}C$, and the linearity error rate was less than 0.22%. After checking the performance of the ROIC using HSPICE simulation, the chip was manufactured and measured using the SMIC 0.35 um standard CMOS process to confirm that the simulation results from the actual design are in good agreement with the measurement results.

• Structural Engineering and Mechanics
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• 제71권2호
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• pp.119-129
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• 2019

Optimum shape and length of laterally loaded piles can be obtained with different optimization techniques. In particular, the Fully Stress Design method (FSD) is an optimality condition that allows to obtain the optimum shape of the pile, while the optimum length can be obtained through a transversality condition at the pile lower end. Using this technique, the structure is analysed by finite elements and shaped through the FSD method by contemporarily checking that the transversality condition is satisfied. In this paper it is noted that laterally loaded piles with optimum shape and length have some peculiar characteristics, depending on the type of cross-section, that allow to design them with simple calculations without using finite element analysis. Some examples illustrating the proposed simplified design method of laterally loaded piles with optimum shape and length are introduced.

• 대한임베디드공학회논문지
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• 제15권6호
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• pp.307-316
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• 2020

Machine learning model data is highly affected by performance. preprocessing is needed to enable analysis of various types of data, such as letters, numbers, and special characters. This paper proposes a development environment that aims to process categorical and continuous data according to the type of missing values in stage 1, implementing the function of selecting the best performing algorithm in stage 2 and automating the process of checking model performance in stage 3. Using this model, machine learning models can be created without prior knowledge of data preprocessing.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권4호
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• pp.210-220
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• 2002

We analysised the effect of harmonics on electric machines of substation power system barred on quantitatively measured harmonics and proposed the methods for prevention of harmonics through checking on transformer, rectifier and cable's capacities against harmonics with reference to KEPCO's electricity service standard. In order to analysis harmoninics of silicon rectifier that is power source in DC substation, computer simulations for a substation with TR of high voltage distribution switchboard are performed. Simulation results show that the total harmonic distortion factor becomes smaller for TR primary and receiving points in order rather than silicon rectifier which is harmonic generation source so that the harmonics generated frets each rectifier are outflowed to power supply and high voltage distribution switchboard The result of higher distortion factors of voltage and current for rectifier with 100% load than those with 50 % and 30% indicates that the waveform of voltage and current for the real substation power system at the office-going and the closing hours with heavy loads might be more distorted. As proposed methods for harmonic reduction, the conventional 6 pulse-type for substation is required to be replaced by 12 pulse-type for reduction of 5th and 7th harmonics. The active filter rather than the passive filter is more effective due to severe variance of rectifier loads, but the high cost is price to be paid. In view of installation area and costs, the use of 12 pulse-type transformer is desirable and then the parallel transformer and the rectifier within the substation must be replaced at the same time. Other substations with parallel feeder can use 6 pulse-type transformer.

• Journal of Nutrition and Health
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• 제35권8호
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• pp.886-895
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• 2002

Introduction and application of virtual education has been rapidly increased in these days. A variation of information communication technology has an effect on education in interconnect with network as internet in the world that exceed the limit of time and regional. Computer and network communication technology through the medium of internet make an entrance cyber education as a new education paradigm. It must be affective on learner who have various educational characteristics and requirements. It begins to appear quality, quantity improvements of knowledge and the development of information technology that web based cyber education. This study was conducted to develop the web based education program and to evaluate the effectiveness of learning satisfaction and accomplishment and to compare the cyber lecture system with the traditional lecture system During the second semester of 2001, this study was investigated 317 registered students in a "Food and Culture" class at Kyungwon University. The data were obtained from pre and post-study with self-administered questionnaire. The evaluation and satisfaction score of students who were registered in cyberclass was negative tendency to compare pre with post-test scores, because of insuffciency of computer-aided lecture system. The major problem was inconvenient in checking system for connecting times in cyberclass which was one of evaluation point in final score. Another problem was frequently disconnection during cyber studying and not to concentrate each time in the cyber lecture because of eye fatigue, boring due to less interesting contents than other newly developed web-site. The students was prefer to mix type of the cyber and traditional lecture type class. The result of final score an each class, the score of cyber class (71.36 $\pm$ 22.44) was significantly lower than other groups (mixed type : 76.66 $\pm$ 19.99, traditional type :79.17 $\pm$ 15.72) (p < 0.05). Cyber class was attempted to present a useful and interesting teaching and learning tool which can be applied successfully in a longer term. The result suggest that various teaching and learning strategies should be developed considering the fact that the student learn alone most in time.t in time.

• 한국지역사회생활과학회지
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• 제21권4호
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• pp.581-593
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• 2010

This study was performed to find out the correct recognition and stabilization of the food labeling system, and the dietary behavior of college students for processed food as well as their recognition of the food labeling system as observed according to their residence type. A questionnaire was composed with three divisions containing general items, the dietary behavior for processed food and the effectiveness of the nutrition labeling system. The data was analyzed by SPSS WIN 17.0 and the results are as follows; The findings showed differences according to residence type were the intake frequency of processed food, the ways of preservation and the reasons of returning or exchange of the purchased processed food. And there was no difference in the recognition of dietary behavior for processed food and food nutrition labeling system. For overall perception of the dietary behavior and the recognition of the food labeling system, the ratio of college students who considered selection standard related to health when purchasing processed food was low. And the ratio of those who checked the label for milk and dairy products or instant food which is concerned with decomposition was high. On the contrary, the ratio of checking was relatively low for beverages, noodles and cookies. Many answered that the reason for having checked the food label was to find out the safety of the food and that of having read the nutrition label was to control weight and to check the nutrition ingredients. In general, many answered positively for the recognition and the necessity of food labeling system, but the actual practice of selecting and managing processed food was poor.

• 한국산학기술학회논문지
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• 제7권5호
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• pp.817-822
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• 2006

다이아몬드는 산업적으로도 보석으로서도 경제적으로 매우 유용한 소재이다. 최근의 소형 고압고온 처리기의 발달로 저급한 갈색의 보석용 천연다이아몬드를 쉽게 고부가가치의 보석인 무색 또는 팬시칼라의 다이아몬드로 향상시키는 처리기술이 가능하게 되었다. 이러한 처리 다이아몬드는 천연의 무색, 팬시칼라 다이아몬드와 물성이 동일하여 기존의 보석감정 방안으로는 구별이 어려워서, 처리 다이아몬드를 경제적이고, 신속하고, 비파괴적으로 천연다이아몬드로부터 감별해 낼 필요성이 생겼다 기존의 광학적인 확대분석으로는 천연석과 처리석의 감별이 불가능하였다. 마이크로 라만 분석기를 이용하여 다이아몬드의 고유피크가 고압고온 처리시의 잔류응력에 의해 이동되는 현상으로 처리석의 감별 가능성을 확인하였다. Type I 다이아몬드는 처리에 의해 $10^4$ 정도의 압축스트레인이, Type II는 인장 잔류 스트레인이 존재하였다. 따라서 적절한 처리전의 기준시료가 있다면 이러한 잔류응력을 확인하는 것이 가능하였다.

• 농촌계획
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• 제29권3호
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• pp.53-67
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• 2023

In this study, the problem of the idleness of public buildings in rural areas is seriously emerging, but there are no clear standards for assessing the utilization of these buildings. Therefore, this study endeavors to investigate the actual state of idleness of buildings created by rural area development projects based on the criteria for each type. As part of this study, rural facilities were selected in two locations in Sangju City and Miryang City among the target areas of the Rural Agreement. Utilization evaluation criteria were developed to identify the conditions of underutilization. In order to determine the utilization pattern for each facility type, an in-depth interview with the operator and an inspection of the facility were conducted. Based on the analysis, the degree of utilization (e.g., low use, non-use, etc.) was different for each facility type, and among the four facility types (rural tourism, culture and welfare, exercise and recreation, income-based), rural tourism was rated as the least efficient. It has been found that the operating entity's capacity has a significant influence on the utilization of facilities. Socioeconomic factors, such as a decrease in utilization rates, are greatly influenced by the operating entity's capacity. Therefore, support from local governments as well as the national level is required to recycle idle facilities. Lastly, this study suggests the need for different standards for utilization, depending on the type of facility. This moves beyond checking the degree of idleness by the same standard that was previously implemented.

• 과학교육연구지
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• 제35권2호
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• pp.127-137
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• 2011

이 연구의 목적은 현미경을 이용한 생물 실험에서 고등학생들의 관찰 결과 보고의 오류 유형 분석틀을 고안하고 적용하는 것이다. 연구를 위해 B광역시 소재 인문계열 남자 고등학생 12명을 대상으로 5가지 관찰 실험을 수행하였다. 실험을 수행하기 전 문헌분석을 통해 관찰 결과 보고 오류 분석틀을 고안하였다. 실험 수행에서 학생들은 사전 지식 확인지를 작성하였고, 관찰 결과는 실험보고서에 기록하였다. 실제 결과 사진과 학생들이 제출한 실험보고서를 비교 분석하여 관찰 결과 보고의 오류 유형을 분석하였다. 연구 결과를 실제결과와 결과보고간에 일치한 일치보고의 비율이 낮게 나타났다. 이는 관찰 방법과 기록 방법에 대한 교육의 부재 때문으로 볼 수 있다. 실제 결과를 객관적으로 관찰하는 훈련과 결과 중심의 확인용 관찰이 아니라 제대로 된 관찰이 가능한 실험 환경의 개선이 필요하다. 또한 관찰한 사실대로 기록하는 연구의 진실성과 관련된 과학 연구윤리 교육이 실시되어야 한다. 본 연구에서 고안 적용한 관찰 결과 보고의 오류 분석틀은 교사들이 관찰 전략을 계획하고 올바른 관찰 관점과 방법의 안내를 위한 기초 자료로 활용할 수 있을 것이다.

• 한국작물학회지
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• 제44권4호
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• pp.355-363
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• 1999

The experiments were carried out to elucidate the varietal variation of retrogradation in aged cooked rice and its association with some physicochemical properties of milled rice. The fifteen rice materials were selected from forty-three low-amylose japonica and Tongil-type rice cultivars based on palatability and retrogradation of cooked rice stratified by preliminary sensory evaluation of warm and cooled cooked rice. One japonica glutinous rice variety was included for comparison of retrogradation of cooked rice. The $\alpha$-amylase-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The desirable checking time for evaluating the varietal difference in deterioration of aged cooked rice was four hours after storing in room temperature and two hours after preserving in refrigerator based on the largest coefficients of variations in degree of retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. The retrogadation index represented by the percentage of retrogradation difference between warm and cooled cooked rice to original estimates of warm cooked rice was significantly affected by the degree of retrogradation of cooled cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked nce. The varietal difference in retrogradation of cooked rice can be effectively classified by scatter diagram on the plane of upper two principal components based on some retrogradation properties of cooked rice. The deteriorated structural change in cooled cooked rice by observing through the scanning electron microscope was more conspicuous in the fastly retrograded cooked rice than in the slower one.