• 한국초등과학교육학회지:초등과학교육
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• 제43권2호
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• pp.269-283
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• 2024

본 연구는 '기체가 공간을 차지하고 있음을 알아볼 수 있는 실험'이 2015 국정 과학 교과서와 검정 교과서에 제시된 특성을 비교하고, 실험의 타당도 검사 및 문제점을 파악하여 이를 개선하고, 그 효과성을 검증해보고자 하였다. 이를 위해 첫째, 국정 교과서와 검정 교과서 7종의 주요 준비물, 실험 방법, 제시된 사례를 분석한 결과 5개 교과서(71.4%)의 실험이 국정 교과서의 실험과 같거나 거의 유사하게 구성된 것으로 나타났다. 따라서 과학교과서의 다양성과 창의성을 확보하기 위해 다양한 종류의 교과서가 개발되었지만 대부분 기존에 제시되어 있던 실험을 그대로 제시하고 있었다. 둘째, 현행 실험의 경우 학생에게 다소 어려운 추론 능력을 요구하고 있고, 구체적이며 직관적인 관찰이 어렵다는 문제점이 있었다. 또한 초등학교 교사는 현행 실험의 타당도가 매우 낮다고 응답하였다. 셋째, 개선된 실험은 타당도가 높은 것으로 나타났으며, 실험 집단의 경우 비교 집단과 비교하여 사후 검사에서 통계적으로 유의한 차이가 있는 것으로 나타나 개선된 실험이 학생들의 탐구능력 함양에 효과가 있는 것으로 나타났다. 그리고 개선된 실험은 컵 속의 물과 공기를 시각적으로 구분할 수 있고, 감각을 통해 현상을 직접 관찰할 수 있으며, 학생 수준에 적합한 활동으로 구성된 것으로 분석되었다. 따라서 본 연구는 '기체가 공간을 차지하고 있음을 알아볼 수 있는 실험'을 직접 지도한 경험이 있는 초등학교 3학년 교사를 대상으로 의견수렴과 협의 과정을 통해 현행 실험의 문제점을 찾고, 개선된 실험을 개발하며, 그 효과를 검증하여 현재 개발되고 있는 2022 검정 과학과 교과서에 시사점을 주고자 하였다.

• 한국임상보건과학회지
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• 제1권2호
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• pp.21-29
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• 2013

Purpose. This study was to investigate that the adjustment of Chiropractic pelvis method have effect on body balance and improvement people who has some problem in their daily life. Methods. With 20 students of experiment group and 20 students of compare group who has cervical syndrome, experiment group has adjustment of chiropractic pelvis 2 times a week for 4 weeks, the other group who didn't take any action. Results. As a result, center of body of experiment group wasn't improved relations between left and right statistically. But the relations between front and back of center of body increased statistically, cross analysis relations between short leg and center of body increased statistically. Conclusions. As a conclusion, experiment group with the front of center of body was improved 12.88% average of center of body. Experiment group with back of center of body was improved 13.84% average of center of body. This result come to the conclusion that chiropractic pelvis adjustment help the front and back of body balance.

• 한국의류학회지
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• 제14권4호
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• pp.281-291
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• 1990

Experiment I and II had done to develop the solar heat proof hat for field work in the summer. In the experiment I physical characteristics of several fabrics was tested to determine which one Is proper to make the solar heat proof hat. On the base of above results in the experiment II three improved solar heat proof hat was deviced and tested solar heat proof effect and compared the existing summer working hat by wearing trials in the environmental chamber. The results obtained were as follows. 1. In the view of the physical characteristics of six fabrics (Blue T/C, White poplin, Vapor transfer silver coating nylon taffeta, No vapor trans(or silver coating nylon taffeta, Aluminum coating T/C, Microporous fabric), the light color T/C and no vapor transfer silver coating nylon ta(feta is proper to make improved solar heat proof working hat. 2. Three improved hats that are made of white T/C, grey T/C and no vapor transfer silver coating nylon taffeta have more solar heat proof effect than the existing summer working hat. 3. Among the three improved hats, the improved hat that is made of no vapor transfer silver coating nylon taffeta is most effective to proof the solar heat.

• Design & Manufacturing
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• 제13권3호
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• pp.48-52
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• 2019

As the consumer market in the mold, automation and aerospace industries grows, the demand for chemical machining using on electrochemical polishing increases. To enhance the surface roughness and gloss of the micro-needle, we have studied for an electrochemical polishing. Electrochemical polishing requires the chemical reaction of solution and material according to the electrolyte and electrode. In this study, sulfuric acid(30%), phosphoric acid(50%), and DI-water(20%)were used as the electrolytic solution, and the electrolytic solution temperature used $58^{\circ}C$. Electrochemical polishing was carried out in experimental conditions, and the micro-needle experiment was carried out from the basic experiment to obtain the experimental conditions. Experimental results show that as the voltage and current increase, the surface roughness improved and the gloss is improved. So, the best result for this experiment was obtained in condition 6, which improved micro-needle.

• 대한화학회지
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• 제50권5호
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• pp.404-414
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• 2006

연구에서는 고등학교 과학 교과서에 제시된 화학반응속도 측정을 위한 실험을 수행할 때 관찰되는 현상을 이해함으로써 교과서 실험의 문제점과 그 원인을 분석하여 개선 방안을 제시하였다. 이를 위하여 화학반응속도 측정과 관련된 단원의 교과서 내용을 분석하였으며, 실험을 수행할 때 발견되는 문제점을 실험 분석을 통해 제시하였다. 교과서에 제시된 수상치환법으로 실험을 하였을 때 부피 변화가 지연되어 관찰되는 현상과 반응속도가 초기에 증가하는 현상이 관찰되었다. 이러한 문제를 해결하기 위한 개선된 실험 방법을 제안하였다. 개선된 실험에서 반응속도는 시간에 대해 일정하게 측정되었고, 그 결과를 수소이온 농도와 마그네슘 리본의 표면적의 관점에서 해석하였다.

• Journal of Nutrition and Health
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• 제36권10호
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• pp.1071-1082
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• 2003

The objective of this study was to evaluate and improve the microbiological quality of HACCP application in school foodservice operations. The microbiological quality of foods and utensils were evaluated two times at each critical control point (CCP) with 3M petrifilm in five Daegu elementary schools. Two processes were evaluated: Heating process and after-heating process. The CCPs of the heating process were receiving, cooking and serving temperatures. The CCPs of the after-heating process were personal hygiene, cross contamination avoidance and serving temperature. After the first experiment, 31 employees of five schools were classroom educated, trained on-site, and pre- and post-tested on HACCP-based sanitation with the goal of improving the microbiological quality of the foodservice. Scores representing knowledge of holding, thawing, washing, food temperature, sanitizing and food-borne illness increased after education. In the heating process, internal food temperatures in the first and second experiments were higher than 74$^{\circ}C$, the holding temperature in the first experiment was less than 6$0^{\circ}C$. In the second experiment, the serving temperature improved to a satisfactory level. The microbiological quality in the second experiment improved by decreasing the time from cooking to serving. In the after-heating process, the ingredients were boiled before being cut in the first experiment. In the second experiment, ingredients were cut before being boiled, improving microbiological quality. Also in the second experiment, cooking just before serving food improved its microbiological quality through time-temperature control. These results strongly suggest it is essential to measure microbiological quality regularly and to educate employees on HACCP continuously, especially time-temperature control and cross contamination avoidance in order to improve foodservice quality.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2004년도 춘계 학술대회지
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• pp.104-105
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• 2004

[ $\bigcirc$ ] In the phenology model of ORYZA2000, the effect of photoperiod on the developmental rate was a little ignored because most crop parameters were measured with IRRI varieties which are insensitive to photoperiod, therefore it is very difficult to apply this phenology model directly to Korean varieties which are usually sensitive to photoperiod. $\bigcirc$ After introducing PPFAC and PPSE to improve the phenology model, the precision of heading date prediction was improved but not satisfied. $\bigcirc$ In the growth simulation using data from several regions, yield tended to be overestimated under high nitrogen applicated condition. $\bigcirc$ The precision of yield was much improved by introducing nitrogen use efficiency, but still different between regions because of different soil fertility or property of irrigation water between regions

• 대한화학회지
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• 제50권4호
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• pp.328-337
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• 2006

연구의 목적은 고등학교 과학 교과서에 제시된 염화구리(II) 수용액의 전기분해 실험의 문제점을 분석하여, 학생들이 실험을 용이하게 수행하게 하고 환기 장치가 없는 과학실 여건을 고려해 염소 기체 발생으로 인한 안전 문제의 발생을 줄이기 위한 개선 실험을 제시하기 위한 것이다. 연구를 위하여 고등학교 11종 과학 교과서에 제시된 염화구리(II) 수용액의 전기분해 실험을 실험 방법에 따라 분류하고, 중등학교 화학 교사들에게 과학 교과서에 제시된 실험 방법대로 실험을 수행하게 한 후 문제점을 분석하여 개선 실험을 모색하였다. 연구 결과에 의하면, U 자관과 가지달린 U 자관을 반응 용기로 사용한 염화구리(II) 수용액의 전기분해 실험에서는 반응속도가 느려서 부반응으로 부산물이 발생하는 문제점이 있었으며, 비커를 반응 용기로 사용한 실험에서는 두 전극이 분리되어 있지 않아 각 전극에서 일어나는 화학반응을 분리하여 관찰할 수 없었다. 그리고 전기분해 장치를 반응 용기로 사용한 실험에서는 반응 생성물의 성질을 확인하기 어려운 문제점이 있었다. 이러한 문제점들을 개선하기 위하여 ㅂ자 모양의 반응 용기를 사용한 결과, 전기분해 반응속도가 빨라졌고, 각 전극에서 생성되는 반응 생성물의 특성을 분리해서 관찰할 수 있었다. 또한, 염화구리(II) 수용액의 사용량과 (-)극 주변에서 일어나는 부반응으로 인한 부산물의 생성량을 줄일 수 있었다. 그러므로 ㅂ자 모양의 반응 용기를 사용하는 개선 실험을 고등학교 과학 탐구 실험에 활용한다면, 염화구리(II) 수용액의 전기분해 실험을 용이하게 수행할 수 있어, 수용액의 전기분해에 관한 과학적인 개념 형성에 도움을 줄 수 있을 것이다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.1173-1176
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• 1995

We design and analyze two type stators for brushless DC linear motors by the experiment and the computational analysis. For a U-shape stator, the maximum manetic flux density by the finite element method(FEM) is large than that by the experiment by 1.0~2.2%. The result by the FEM is so accurate that it can be applied to the geometric design for the optimization. To increase the maximum magnetic flux density, we suggest an improved stator and analyze it by the 3-D and 2-D models. The maximum magnetic flux density of the improved stator is large than that of the U-Shape stator by 2.7%. Considering the size of the improved stator and maximum magnetic flux density, we determine that the optimized thickness is 5mm for a given specification.

• 동서간호학연구지
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• 제7권1호
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• pp.18-31
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• 2002

This study, as a basic research to manage a Chinese Medicine Health Promotion Center by way of showing an example, is a before and after experiment research for simple group to verify a difference with cholesterol, health status and perception of health in order to confirm a effectiveness of diet and regimen according to the 4th status of physical constitution. Research object was chosen of 42 persons who operate a physical constitutional dietary regimen among them after selecting professors and clinical nurses (55 persons) majoring in the science of nursing who participated in Chinese Medicine-oriented Nurse Training Course from Aug. of 2001 to Feb. of 2002 all over the country. Diagnostic tools for physical constitution was used of the questionary that is currently consisted of physical constitution grouping test in Eastern & Western Diagnose Center of K Medical Center, and rating of health status was used of the tool that standardized CMI(Cornell Medical Index) to be available for Korean, and perception measurement for health status was used of a visual analogue scale for the health status that each one perceive personally, and physiological status was measured of cholesterol in blood. Analysis for the collected data was carried out by percentage, $X^2$ test, paired t-test according to research object by using SPSS, and the results of this study are as follows. 1) There was no difference with cholesterol before or after the experiment for objects. As a result of estimation about difference with health status by areas before or after the experiment, there are more improved result in eyes, ears, digestive organs, bones and sinews organs, frequency of a disorder, habit, adaptation status, angry, healthy status than before the experiment. As a whole, after the experiment the health was more improved than before the experiment. As the result to inspect a difference of health perception between before and after experiment, after the experiment the health perception level was improved than before, however there was no meaningful differences. 2) As the result to inspect a difference of cholesterol between before and after experiment according to object's physical constitution, in the case of So-yang-in(a person with the minimum male: according to the male and female principles(the sun and the moon)) among the 4th status of physical constitution there was only meaningful difference statistically, however, after the experiment their cholesterol's value was increased. As the result to inspect the difference of health status between before and after the experiment according to physical constitution, all of Ta-um-in(a person with maximum the female), So-yang-in(with the minimum male), So-um-in(with the minimum female) had a meaningful difference before and after the experiment, which means that in all case by physical constitutional groups, after the experiment their health status was more improved than before the experiment. As the result to inspect a difference of health perception between before and after according to physical constitutions, in the case of Tae-um-in and So-um-in, average score after the experiment was risen than before the experiment so that it means that the level of health perception was improved, however, there was no meaning statistically. According to the above results, if continuous diet and regimen by each physical constitutions could be implemented, it is certain that the health could be maintained and promoted. And, what we are healthy is for oneself to feel it subjectively. However, I think that cholesterol score in blood that we can view objectively could be changed distinctly if we can implement a strict diet and regimen. Accordingly, it is necessary for a method and period of experiment to be more strict and longer. According to the above results, I would like to suggest as follows. 1) In order to understand health status by Korean's physical constitutions and to generalize it, these research will be repeated against much more objects that could be selected by proper grouping method to consider a representative. 2) It is necessary for a research to inspect health status by physical constitution by developing a health status measurement tool that has higher confidence and propriety based on physical constitutional theory.