• 제목/요약/키워드: class field

검색결과 1,577건 처리시간 0.028초

Conceptual design and fabrication test of the HTS magnets for a 500 W-class superconducting DC rotating machine under 77 K

  • Choi, J.;Kim, S.K.
    • 한국초전도ㆍ저온공학회논문지
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    • 제23권4호
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    • pp.35-38
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    • 2021
  • Conventional direct current (DC) rotating machines are usually used for crane and press machine using high torque in metal and steel industries, because of a constant output power along variable rotating speed. A general DC motor with permanent field magnets could not increase a magnetic flux density at a gap between armature coils and field magnets. However, a superconducting DC motor has field magnets composed with high temperature superconducting (HTS) coils and it could increase the magnetic flux density at the gap to over 10 times than those of a general DC motor by control the excitation current into HTS coils. The superconducting DC motor could be operated with extremely high torque and constant output power at a low rotational speed. In this paper, a 500 W superconducting DC rotating machine was conceptually designed with a LN2 (Liquid Nitrogen) cooling method and the operation characteristics results of HTS field magnets were presented. The two no-insulation HTS magnets for a 500 W superconducting DC rotating machine were fabricated. The excitation current for the HTS magnets could be controlled from 0 to 40 A. This test results will be available to design large-sized HTS magnets for a number of hundred kW class superconducting DC rotating machine under LN2 cooling system.

생태복원재료 관련 국내 실정법의 속성 분석 (An Analysis on the Properties of the Domestic Laws Connected with Ecological Restoration Materials)

  • 신익순
    • 한국환경복원기술학회지
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    • 제7권1호
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    • pp.85-96
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    • 2004
  • The purpose of this study is to present the legal object in the related legislation taking the present condition of the domestic laws and the leading cases connected with ecological restoration materials and analyzing their properties according to the analytic standards which are legal class and ecological restoration material items, the present condition by the field of ecological restoration business, interrelationship between the law and the leading cases, comparison of the domestic laws with the foreign regulations. The results of this study are as follows; 1) Detailed enforcement regulation(36.5% of totals), enforcement regulation(32.4%) and law(31.1%) as legal class of the domestic legislation relating to ecological restoration materials are in the order of frequency that shows the little strong frequency at low-ranking class. By items, the number of legislation relating to planting material holds about majority, next to it, stone material, soil material and wood material are in the order of frequency. 2) By the field of ecological restoration business, legislation relating to administration forms the highest frequency(36.3% of totals), next to it, material properties(23.4%), plan design(13.0%) are in the order of frequency. 3) For the number of the leading cases by items of ecological restoration materials, those are, for the most part, them relating to planting material(93.8% of totals). The number of legislation relating to planting material forms the highest frequency at laws and the leading cases in common. 4) The domestic legislation connected with ecological restoration materials is mainly to be in legal class of the positive law, on the contrary, a foreign country has legislation widely consisted of laws, ordinances and other general regulations. Some foreign country legislated the topsoil conservation act, but not to domestic. The result of this study will be applied to legislature and court as reference materials, and to the public and public officer as a means of an understanding of ecological restoration materials.

레이저를 이용한 피부치료의 한의학 임상활용-모세혈관 확장증을 중심으로 (Clinical Application of Dermatic Care by Laser Therapy in Korean Oriental Medicine)

  • 윤소원;김민희;윤화정;고우신
    • 동의생리병리학회지
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    • 제18권3호
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    • pp.939-941
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    • 2004
  • Phototherapy have perpetual history, we can see an instance of it in Yellow Emperor's Conon of Medicine(黃帝內經) and Laser therapy is a field of Phototherapy being used frequently in the latest time. We treated patients with telangiectasia by laser therapy and experimented it's efficacy and studied the means of clinical application in Korean medicine. We report the capabilities of application of laser therapy, based on Korean medical theories by using resemblance between laser therapy with kyung-rak(經絡) control technique in the line that connects with the past.

대형증발계 증발량의 일 변화 (Short-term Variation in Class A Pan Evaporation)

  • 이부용
    • 한국농림기상학회지
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    • 제4권4호
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    • pp.197-202
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    • 2002
  • A new method is used to estimate the amount of water evaporation from Class A Pan with higher precision and accuracy. The principle of method is to detect the weight change of a buoyant sinker resulting from a change in water level of Class A Pan. A strain-gauge load cell is used to measure the weight change. Field observation of evaporation was done at Pohang Meteorological Station from June 24 to August 4, 2002. By using this new method, it is possible to measure hourly evaporation accurately even under a strong solar radiation and wind disturbance, enabling a direct comparison of evaporation with other meteorological elements. At night, under low humidity and high wind speed conditions, more evaporation was recorded than during daytime. Maximum evaporation rates observed during this period exceed 1.0 mm/hour under the sunny and windy conditions with low humidity. To understand relationships between meteorological elements and latent heat flux at ground level, we suggest intensive held experiments using high accuracy evaporation recording instruments with hourly time interval.

경영수업을 위한 역량육성형 교수법 개발 (Development of Teaching Methods for Competency Development in Business Class)

  • 성행남
    • 디지털산업정보학회논문지
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    • 제13권3호
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    • pp.83-104
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    • 2017
  • It is the approach of development of teaching methods for competency development in business class. This study distinguishes areas that can be commonly applied to many business subjects. And we derive core competencies from the basic skills of NCS. The results of this study are as follows. First, we have established an opportunity to distinguish the subject field of business administration(personnel/organization/strategy, production/operation management, marketing, financial/finance/insurance, accounting, MIS). Second, we have proposed guidelines for the setting of the each subject goals and the setting of the professor's competency. Third, we have summarized teaching method which are studied as valid in business class(lecture method, problem based learning method, action learning teaching method, and management simulation teaching method) and we suggested how to apply teaching methods to the each subject.

Effects of Problem-Based Learning (PBL) in Fashion Design Classes

  • Park, HyeSook
    • International Journal of Advanced Culture Technology
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    • 제7권4호
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    • pp.222-228
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    • 2019
  • In recent years, in order to enhance the problem-solving skills required by the industrial field, universities have introduced the Problem-Based Learning(PBL) method to solve the problems caused by the lack of creativity, problem solving ability and self-directed learning. This study applied PBL class methods such as 'learning based on individual specific problems', 'self-directed learning', and 'small-group learning of small members' to practical design of fashion design. To do this, I conducted a questionnaire after conducting research based on the PBL module for one semester in a practical class of fashion design major at P University. As a result of the survey, the satisfaction and achievement of the class conducted by PBL learning method was improved than the existing teaching method. As such, if PBL class is used as a way of solving problems through close communication between professors and learners, it is expected to be established as a learner-centered education method that can improve creativity and professionalism.

자바 클래스 파일 최적화 (Java Class File Optimization)

  • 홍경표;이야리;오세만
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2001년도 봄 학술발표논문집 Vol.28 No.1 (A)
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    • pp.55-57
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    • 2001
  • 자바언어는 이질적인 네트워크 환경에서 프로그램 개발이 적합하도록 설계된 언어이다. 자바언어의 특징은 소프트웨어를 쉽게 개발하는데 유용한 것은 사실이지만, 성능상 제약이 따르게 된다. 즉 자바는 클래스 파일이 이동하여 JVM 환경에서 인터프리팅 되는 시스템이므로, 클래스 파일이 이동하며 실행되는 동안의 성능의 저하 없이 자바의 특징을 이용하려면 복잡한 최적화와 실행 시스템이 요구된다. 본 논문은 네트워크 상에서 동적으로 다운로드 되는 클래스 파일의 최적화에 있다. 클래스 파일이 인터프리팅 되는 시스템이 보다 적은 네트워크 로드를 가지고 실행할 수 있도록 하며, 효율적인 실행 속도를 보이도록 하는 것이다. 여기서는 Class Field Optimizer는 내부적으로 Bytecode Optimizer와 ClassGen을 이용하여 실행시간을 개선하고 전체 클래스 파일의 크기를 줄이게 된다. Bytecode Optimizer는 peephole 최적화를 수행하고, bytecode 의존적 최적화, 그리고 전역최적화를 행하게 된다. ClassGen은 클래스 파일의 포맷에 따라 bytecode를 분석하고 본래의 클래스 파일보다 작은 크기의 클래스 파일을 생성하게 된다. 최적화된 클래스 파일은 부분적으로 클래스 파일의 최적화를 가져와 전체 클래스 파일의 크기를 줄이고, 인터프리터를 통하여 실행될 때 수행 속도면에서 좀더 빠른 실행 속도를 가지게 된다.

'우주와 지구' 분야에서 초등 예비교사들의 SSI 프로그램 수업 적용 효과 (The Effects on SSI program of elementary pre-service teachers in 'The Universe and the Earth')

  • 이용섭;김순식
    • 대한지구과학교육학회지
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    • 제7권3호
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    • pp.338-346
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    • 2014
  • In this study, find out of recognition of the effect of science, society and ethical aspects on natural disasters and understanding degree of knowledge applying for SSI class aimed at elementary pre-service teachers by developing SSI training program of the 'Earth and Space' field. Also, after SSI class application we examined the change perceptions of elementary pre-service teachers. SSI training program was that elementary pre-service teachers participated in the SSI class of a variety of subjects in the field of 'Earth and Space' and directly joined in the decision-making process and reflectional discussion with colleagues as conducted in this class reflective discussion with the pre-primary teachers pre-service teachers. Elementary pre-service teachers were understanding of the nature of the science and to understand in more depth about the SSI class characteristics. This study, second grade 115 people who was taking 'science and teaching materials' course in B National University of Education at B city participated. In order to apply for SSI class, one semester based on 15 weeks until seven weeks were science and teaching materials and based on the nature of science, after 8 weeks we set the theme of the contents related to the Earth and space and give lesson applied for SSI. During 8 weeks, test subjects 4 classes were taking 50 minutes a week 100 minutes. First time has theoretical lessons in topics related to the 'Earth and space' and on the second week, each classes participate in the decision-making processes respectivly by dicussing and debating on the first week's topic as regarding social and moral aspects of it. We obtained the following results. First, elementary pre-service teachers were acquiring the results of 67% in the knowledge aspects of the 'Earth and space'. This result was determined that most of the elementary pre-service teachers were liberal arts in high school. Second, while participating in the SSI class, elementary pre-service teachers were concretely aware of the nature of SSI and the characteristics of the class. Third, the elementary pre-service teacher are thaught that introduction education courses about 'Earth and space' are needed but most of the students responded that this would require a lot of effort of teachers. This was derived from not familiar class form that did not fulfill in the science teaching methods until now.

WBI 개발 적용을 통한 교수-학습이 수학과 학업성취 신장에 미치는 영향 -중학교 1학년 함수단원을 중심으로- (The Effect of Teaching-Learning through Development and Application of WBI on the Learning Achievement in Mathematics -Focusing on the Unit 'Function' in the 1st grade of Middle School-)

  • 김웅환;오정학
    • 한국학교수학회논문집
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    • 제4권2호
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    • pp.103-113
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    • 2001
  • The teaching-learning method utilizing Web makes it possible for the students take the initiative in any field and offers the teaching strategy, methodology and teaching-learning materials suitable for students' ability and standard. The purpose of this study is to investigate the characteristics of WBI in mathematics class for the effective teaching and learning focusing on the unit 'Function' in the 1st grade of middle school and verify its effectiveness by developing the WBI programs which can progress learning achievement and applying them to math class. Two hypotheses were established for this study. Hypothesis 1 : There will be meaningful difference between the group that studies under WBI and the one that doesn't, Hypothesis 2 : There will be meaningful difference in the attitude and interest toward learning between the group that studies under WBI and the one that doesn't. In order to find out the result, I have made a comparative analysis through t-verification on the object of two classes of the 1st grade in P middle school that I have been working for. The result shows that the class utilizing WBI is more effective than the traditional lecture-oriented class since there is a meaningful difference between the control group and experimental one and also that the class based on WEB has a great influence on students' interest and positive attitude toward math class.

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고등학교 확률과 통계 영역에서 현실적 수학교육의 적용 효과1) (Implementation effects of the Realistic Mathematics Education in Bigh School Probability and Statistics)

  • 김원경;백경호
    • 한국수학교육학회지시리즈A:수학교육
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    • 제44권3호
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    • pp.435-456
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    • 2005
  • This research aims to analyse implementation effects of the Real mathematics Education(RME) in the high school probability and statistics For this aim, two research questions are estabilished as fellows. (1) Is there any improvement of mathematical achievement in the class by RME's lecture than in the class by the mathematics text's lecture ? (2) Is there any improvement of mathematisation level in the class by RME's lecture than in the class by the mathematics text's lecture ? Before answering the above research questions, RME.`s lecture notes and ordinary lecture notes are developed based on the learning principles of the RME and mathematics textbook respectively. Two classes are randomly chosen from a high school located at midium size city and assigned as the experimental group and the control group respectively. The 20 hours of the RME's lecture notes is administerd to the experimental group and the 20 hours of the odinary lecture notes is administerd to the control group. It is shown that the class by RME's lecture is more effective in both of the mathematical achievement and the mathematisation activity than the class by the ordinary lecture. Hence, it is urged from the result of this research that RME's context will be developed and the RME's lecture will be implemented in the other field of high school mathematics.

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