HFC-134a와 대체냉매 HFC-152a에 CF_3I를 혼합한 자동차냉매 특성

권일욱,박찬수,홍경한,문기선,최운수,서의경,윤갑식,이종인,하옥남 朝鮮大學校 機械技術硏究所 2002 機械技術硏究 Vol.5 No.1

These days, an attention of environment has been increasing all over the world. to prevent the green house effect and destruction of an ozone layer, an ozone destruction potential(ODP) be zero and a refrigerant for low global warming potential(GWP) is needed. HFC-134a, in which hydrogen is mixed instead of chlorine is a refrigerant used for automobile conditioners and its destruction potential is ecologically zero. However, it is not considered as a perfect substitutive refrigerant as its GWP is high. It is studied refrigerant mixtures in which HFC-134a, HFC-152a and CF_3I with low GWP and zero ODP are mixed by experimentally and concluded as follows; 1. with the variation of speed of compressor outside temperature and flow rate, the heat of evaporator and compressor and coefficient of performance was varied, and influenced the air conditioner. 2. The pressure of evaporator was decreased with increasing the speed of compressor and that of the refrigerant HFC-134a was higher 21% than that of azotrope refrigerant mixed with CF_3I. The overall capacity of condensor and evaporator was increased and HGC-134a was higher than azotrope refrigerant mixed with CF_3I 3. The capacity of evaporator with the refrigerant HFC-134a was higher 6% than azotrope refrigerant mixed with CF31 and the required power with zaotrope refrigerant mixed with CF_3I was higher 11% than that of HFC-134a. 4. The COP of the refrigerant FHC-134a was higher 31% in 1000RPM. when outside temperature was increased, COP was decreased. 5. Performance of HFC-134a is better than azotrope refrigerant mixed with CF_3I but prefered zaotrope refrigerant mixed with CF_3I considering the environment.

보육시설 활동복에 대한 어머니들의 태도 연구

김수경,최선영 가톨릭대학교 생활과학연구소 1999 생활과학연구논집 Vol.19 No.1

The purpose of this study is to investigate the design elements to design functional and creative clothing for preschool children emphasizing the physical, psychological and aesthetic developments. Data were collected from 262 mothers of 2∼7 aged children, residing Pucheon and Seoul. The results of empirical studies were summarized as follows: 1) The clothing aspects considered important by mothers, in order of freqency, were: utility, price, child's attitude, comfort, symbolic, brand, fashionability, design. 2) Children's mothers considered more important, easiness for the child to put on and take off, the amount of clothing necessary for comfortable temperature, comfort of clothing rather than design and fashionability for children's kindergarten life. Mothers seem satisfactory about children's uniform at kindergarten. 3) Preschool children like some aspects of clothing. These were, in order of importance, were: color, activity, cartoon character, texture, prettiness, decoration detail

일부농촌지역의 농약사용실태 및 농약중독 요인 조사

이경민,송주희,장재혁,심수정,강양화,안재경,이숭호,박미영,정문호 대한보건협회 2002 대한보건연구 Vol.28 No.4

Object The usage of agricultural chemical is on the increasing. Use of pesticides has increased agricultural production. However, negative externalities from such use have increased too. Pesticide poisoning is a major public problem. The purpose if this study is to find out the relationship between keeping the safety rules or protective equipments or attending safety education or dose of pesticides use , and poisoning experience. Methods For Gu, H.M. and Pack, S.G. study , we obtained questionnaire data concerning pesticides poisoming. A person interviews on 203 were conducted in two villages in Sinmeari and woulbonri Chunchun , Kangwon province, July 2002. Result 1. 144 people(70.9%) have sprayed pesticides and the rata of experiences of pesticide poisoning was 26% among 144. Spraying time of pesticides was 1-2 hours in 63.9% of farmers. Rate of using the protective equipment was 25.7% (protective clothes), 49.3% (Mask), 48.6 (Gloves), 7.0 (Protective glasses), 64.6% (boots) respectively. 2. Chi-square and multiple logistic regression analysis showed that Duration of spraying per day (<2hr) and using of mask(protective equipment)are significantly association with poisoning experience.(x^2=5.2684 p=0.0217, CI=0.140-0.5853 OR=0.346 p=0.0211 respectively). But no association between poisoning experience and keeping safety rule, attending of safety education. 3. Spraying pesticides. Duration of spraying pesticides, reading manuals and no spraying at fatigue (keeping safety rule) are significantly association with symptom experience(x^2=14.0621 p=0.0002, x^2=7.0639 p=0.0079, CI01.395-10.950 OR=3.908 p=0.0095, CI=0.101-0.726 OR=0.271 0.0094 respectively). But no association between symptom experience and protective equipments, attending of safety education.

窒素 및 生長 調節劑가 무우 生育에 미치는 影響

李長洙,李庚熙 건국대학교 1977 論文集 Vol.6 No.1

This experiment was conducted to investigate the effect of Nitrogen and plant growth regulators on the growth of radish. The results are as follows. 1.In the Nitrogen test, the block applied with ½ amount of Nitrogen as a fundamental, and ½ as additional fertilizer showed the best growth of radish. 2.The leaf growth was decreased by B-9 treatment but root development was stimulated, and the better effect on root growth was taken in the block applied B-9 in the early stage of growth. 3.The leaf growth was stimulated by Gibberellin treatment but the root development was inhibited, and the more severe effect was taken in the block treated with Gibberellin in early stage of growth. 4.The T-R ratio calculated at the time of harvesting showed more than 1.45 in the block treated with Gibberellin and less than 0.97 in the B-9 treatment while it was 1.06 in the Control.

내장재의 연소 및 독성가스 발생 특성 : 방염 카페트, 방염 후처리 합판, 쇼파 내자를 중심으로 The focus for resist-carpet, resist-treatment plywood, sofa leather

김일수,류경옥 韓國火災 ·消防學會 1998 한국화재소방학회논문지 Vol.12 No.2

화재위험성이 큰 유흥업소에서 주로 사용하는 내장재중 방염 카페트, 방염 후처리 합판, 쇼파 레자등 3가지 시료에 대한 연소특성과 CO, CO_2, O_2, NO_x, SO_2, HCN, HCI등 독성가스를 검출하여 화재 위험성을 비교평가 하였다. 연소특성에 있어 방염 카페트가 방염 후처리 합판, 쇼파 레자 보다 연소가 잘 되었고, 폭연 연소가 일어났다. 모든 시료에서 CO의 발생은 연소시작 후 1분 이내에 치사농도를 상회(上 It was studied a compared estimation of the fire risk of the three kinds of the interior materials, such as a resist carpet, a resist-after-treatment plywood and sofa leather. Toxic gases, CO, CO_2, NO_x, SO_2, HCN, HCI were detected during the combustion of the samples. A resist-carpet was more combustible than the resist-after-treatment plywood and sofa leather in the combustion characteristics and has a blow-up-combustion of combustion in all the samples. The generation of CO reached the lethal doses in minute after the combustion was begun. NO_x and So_2 were detected not more that each of the lethal doses, while HCN was detected in the carpet 20.6 times than the sofa leather, and 4.6 times than the resist-after-treatment plywood. HCI was detected in the carpet 4.48 times than the sofa leather and 2.47 times than the resist-after-treatment plywood. It is conclusion that the carpet was the highest in the fire risk among the three kinds of the interior materials.

A Hybrid Control Algorithm for the Direct Drive Robotic Manipulators

李鍾洙,崔京三 弘益大學校 1989 弘大論叢 Vol.21 No.2

본 논문에서는 직접 구동 팔의 효율적인 경로 제어를 위해 이산 제어 성분과 연속 제어 성분의 두 가지가 혼합된, 새로운 하이브리드 제어 방식을 제안한다. 이산 제어 성분은 로보트 팔의 근사적 추정 모델을 이용하여, 로보트의 규정경로를 따라 계산하는 규정 토오크로서, 로보트의 동력학 정보를 계산하기 위해 필요한 많은 계산 시간을 고려하여, 큰 표본 시간을 갖도록 한다. 이 제어 입력은 로보트 관절들간에 상호 작용하는 강한 결합 토오크를 근사적으로 보상한다. 연속 제어 성분은 가변 구조 제어 이론을 변형한 제어 입력으로서, 모델링 오차나 작업부하의 변화에 따른 외란 등에 강하게 대처하여 경로 추적의 정학성을 높일 수 있도록 한다. 최근의 제어기 개발 추세에 따라 제안한 알고리즘을 디지탈 제어로서 실현할 경우 '연속 제어 성분은 이산 제어 성분에 비하여 매우 작은 계산량 만을 필요로 하므로, 두 가지의 서로 다른 표본 시간을 갖는 이산 제어 형태로서 구현할 수 있음을 보였다. 제어 시스템의 안정성을 증명하였으며, 제안한 알고리즘의 효용성을 보이기 위하여 작업 부하 오차, 모델링 오차 및 계산에 의한 제어 입력의 시간 지연을 고려하여 3자유도의 직접 구동 로보트 팔에 대하여 시뮬레이션 하였다.

CMAC를 이용한 로보트 제어기 설계

李鍾洙,崔京三 弘益大學校 1990 弘大論叢 Vol.22 No.2

In this paper, we propose a new manipulator control scheme based on the CMAC neural network. The proposed control consists of two components. The feedforward component is an output of trained CMAC neural network and the feedback component is a modified sliding mode control. The CMAC accepts the position, velocity and acceleration of manipulator as input and outputs two values for the controller: One is the nominal troque used for feedforward compensation(M1 network) and the other is the intertia matrix related information used for the feedback component(M2 network). Since the used control algorithm guarantees the robust trajectory tracking in spite of modeling errors, the CMAC mapping errors due to the memory limitation are little worth consideration.

국내 기능성 화장품의 생산 실태

김혜수,이경화 가톨릭대학교 생활과학연구소 2001 생활과학연구논집 Vol.21 No.1

The purpose of this study is to analyze the real state and problems of production characteristics in Korean Cosmeceuticals manufacturers. This Study accomplished the qualitative survey to Top three cosmetic manufacturers(태평양, LG, 코리아나) which have production lines of Cosmeceuticals. Interviewee are marketers and production managers who have careers in this areas. The results are as follows; 1.Most of market segmentations are focused on the younger generation(age 20 to 39). 2.All of cosmetic brands were offered the variations of skin types by brands and products, which are skin care and nutritional care. 3.It has shown that the evaluation of manufacturers about the consumers' understanding of cosmeceuticals was very low. However, the consumers' satisfaction after using cosmeceuticals was shown to be very high.

아시아 지역 폐렴 구균의 항균제 내성 현황 및 변화 양상 : Asian Network for Surveillance of Resistant Pathogens (ANSORP) Study

정숙인,김나영,손준성,기현균,고관수,서지연,장현하,김연숙,오원섭,백경란,이남용,송재훈,항생제 내성 감시를 위한 아시아 연합 (ANSORP) 대한감염학회 2004 감염과 화학요법 Vol.36 No.1

목적 : 1980년대부터 페니실린을 비롯한 β-lactam 계열과 비 β-lactam 계열 항균제에 대한 폐렴구균의 항생제 내성이 급격하게 증가하여 국내 뿐 아니라 세계적인 문제로 대두되고 있다. ANSORP 에서는 아시아 지역에서 폐렴구균의 항균제 내성과 그 변화 추이, 내성의 기전 및 위험인자를 분석하고자 본 국제 공동 연구를 시행하였다. 재료 및 방법 : 1999년 11월부터 2001년 8월까지 아시아 지역 12개국의 14개 기관에서 폐렴구균 감염증 환자의 임상 검체로 분리된 침습성 폐렴구균을 대상으로 액체배지 미량희석법을 이용하여 16개 항생제의 MIC를 구하였다. 위험인자의 분석을 위하여 폐렴구균 감염증 환자를 대상으로 의무기록지를 조사하였다. Quellung 반응을 통해 혈청형을 결정하였다. 결과 : 총 685균주 중 52.4%가 페니실린에 대하여 비감수성(중등도 내성 22.9%, 내성 29.5%)을 보였고, 그 빈도는 베트남(92.1%), 스리랑카(85.7%), 홍콩(67.9%), 한국(64.5%)의 순이었다. Erythromycin에 대한 비감수성 비율은 베트남(92.1%), 대만(87.7%), 한국(80.6%), 홍콩(76.8%) 등에서 높게 나타났고, 베트남, 대만, 한국, 홍콩 등의 erythromycin의 MIC_(90)이 32㎍/mL를 넘는 고도내성을 보였다. 홍콩, 싱가포르, 대만, 인도에서는 fluoroquinolone에 대한 내성 균주가 출현하였다. 전체 균주 중 다제내성 균주의 비율은 47.7%였다. 혈청형은 19형과 23형이 가장 많았고, 그 외 6형, 14형 등이 있었다. 페니실린 비감수성 감염증의 위험인자로는 5세 미만(OR=1.7; 95%, CI, 1.2-2.4; P=0.002), 기관지폐질환(OR=2.0; 95%, CI, 1.3-3.1; P=0.003), 악성종양(OR=2.3; 95%, CI, 1.2-4.6; P=0.015), 스테로이드의 사용(OR=2.8; 95%, CI, 1.1-7.4; P=0.032)이 확인되었다. 결론 : 침습성 폐렴구균 균주를 대상으로 한 본 연구의 결과 아시아 국가들에서 페니실린, β-lactam 및 macrolide에 대한 폐렴구균의 내성률 및 내성 정도가 급증하고 있음을 확인하였다. Background : Emergence of pneumococcal resistance became a global issue since 1990s. According to the ANSORP studies with clinical isolates and carriage isolates between 1996 and 1999, some Asian countries showed alarmingly high prevalence of resistance to penicillin and other antimicrobial agents. To investigate the changing trends of pneumococcal resistance, ANSORP study group has performed a multinational surveillance study with invasive pneumococcal isolates from Asian countries. Methods : All isolates from various invasive pneumococcal diseases were prospectively collected from 14 centers in 12 countries between November 1999 to August 2001. Broth microdilution tests with 16 antimicrobial agents were performed according to the NCCLS procedures. Serotyping was performed by means of Quelling reaction with use of group-specific antisera. Results : A total of 685 isolates were collected. Overall, 52.4% of invasive isolates from Asian countries were not susceptible to penicillin (intermediate (1), 22.9%, Resistant (R), 29.5%). Vietnam showed the highest prevalence of penicillin non-susceptibility (1 20.6%, R 71.4%) followed by Sri Lanka (1 71.4%, R 14.3%), Hong Kong (1 24.1%, R 76%) and Korea (1 9.7%, R 54.8%). China (I 19.8%, R 23.4%) and Malaysia (1 9.1%, R 29.5%) also showed remarkable increase in penicillin resistance compared with previous ANSORP data, which were less than 10%. Vietnam (92.1%), Taiwan (87.7%), Korea (80.6%), and Hong Kong (76.8%) showed high prevalence of erythromycin resistance. MIG_(90)S for ciprofloxacin were 4 ㎍/mL (Hong Kong) and 2 ㎍/mL (11 Asian countries except Hong Kong), respectively. Conclusion : Compared with previous data from ANSORP studies, antimicrobial resistance among invasive pneumococcal isolates has markedly increased in Vietnam, Sri Lanka, Taiwan, China, and Malaysia. Continuous surveillance of pneumococcal resistance in Asia is strongly warranted.

美國大統領選擧制度에 관한 硏究 : With a Special Emphasis on the Comparative Analysis with the Four Alternatives 特히 直接選擧方式 등 몇몇 方式과 比較하여

朴炅守 東亞大學校 大學院 1984 大學院論文集 Vol.8 No.1

Because the presidential election is one of the most crucial acts in American politics, the method of selecting the chief executive has been debated almost continuously since the electoral college was introduced in 1789. Today, few livelier issues face the America public than the proposal to abolish the electoral college and replace it with a form of direct voting for presidential candidates. This paper represents an attempt to analyze the existing electoral system and compares it with four leading alternatives, i.e., the direct vote, the automatic plan, the district plan, and the proportional plan. After studying the alternatives the author comes to the conclusion that the existing electoral college system best represents the American political tradition as well as its political system characterizing the American federalism.c