원형분극 마이크로스트립 배열 안테나의 소형화 연구

김완호,황인진,정봉식 東亞大學校附設 情報技術硏究所 2004 情報技術硏究所論文誌 Vol.12 No.1

In this paper the compact microstrip array antenna with CP(circularly polarized) radiation for GPS(Global Positioning System) is designed. the compact operation of microstrip antenna is obtained by inserting suitable slits in the radiating patch, and CP radiation by giving the unequal length of two pairs of slits, which splits the resonant mode of interest into two orthogonal near degerate modes. Feed network of array antenna is made by using a two-layer structure and via connection probe. By numerical and experimental results, the patch size of compact CP microstrip antenna is reduced about 40% than conventional one.

취업 및 국가기술자격 취득 증진 방안 연구

이완영,백기영,김영환,장세봉 永同大學校 1997 硏究論叢 Vol.3 No.1

본 연구는 도시공학 전공 학생의 국가기술자격 취득 및 취업, 진학 등에 필수적으로 요구되는 도시공학 관련 기초지식을 연마하고 전공지식을 심화 교육함으로서 산·학·연 연계체계에 기초하여 도시공학 전공 학생의 취업증진을 도모하기 위한 종합적이고 구체적인 방안을 모색하고자 하는 것이다. 이를 위하여 본 연구에서는 사회수요에 부응하기 위한 기술교육의 강화, 국가기술자격 취득 제고, 현장실습제도 등 3가지 측면에서 취업증진을 위한 추진실적 및 문제점을 점검하고 이에 대한 향후 개선방안을 모색하고자 하였다. The purpose of this study is to search for the comprehensive and concrete methods of increasing the graduates' employment based on both fundamental and advanced knowledge concerned urban engineering major. For this , existing condition, problems and improvement of students employment are searched in 3 view points such as strengthening of technical education to follow the social demands, enhancement of acquisition of the national qualifying examination and making the best of the field training system.

중성자 수송방정식의 확산 접근성 해석

盧泰完,高鳳煥 弘益大學校 科學技術硏究所 1997 科學技術硏究論文集 Vol.8 No.-

In some classes of radiative and neutron transport problems that include strongly diffusing media, it might be impractical to refine the mesh enough to enter the regime of thin mesh cells. This is because such media are too optically thick to realistically allow sufficient mesh refinement. Considering that the simplified even-parity neutron transport equation is an approximation to the Boltzmann and even-parity transport equation, it is advantageous if the method has the correct diffusion limit; in other words, it gives generally accurate results in diffusing regimes, even when mesh cells are not thin. Our asymptotic analyses have shown that the so-called thick diffusion limit is satisfied by the finite element even-parity and simplified even-parity transport equations.

이차원 LMS 알고리즘의 Systolic Array 구현

박완수,최훈,홍기섭,박봉수,배현덕 충북대학교 컴퓨터 정보통신 연구소 2000 컴퓨터정보통신연구 Vol.8 No.1

적응알고리듬의 VLSI 구현에 있어서 파이프라이닝이나 시스토릭과 같은 구조적 설계기법을 이용하여 알고리듬을 변환하는 것은 효과적이다. 알고리듬 변환은 z-변환 영역에서 연산의 규칙성과 반복성을 찾아 이루어 진다. 본 논문에서는 이차원 필터와 계수갱신 시스템을 시스토릭 구조로 설계하여 LMS의 확장 형태인 TDLMS을 STDLMS로 변환한다. 변화된 STDLMS를 이용 이차원 ALE를 Altera사의 Max-PlusII 상에서 구현하여 시뮬레이션을 통해 성능을 평가한다. 시뮬레이션 결과 salt-pepper 잡음과 가우시안 잡음에 오염된 화상을 ALE가 개선할 수 있음을 보였다. In VLSI realization of adaptive algorithm. it is necessary and efficient that the algorithm is transformed to structural one suitably using architectural design techniques such as pipelining or systolic array. These transform method use regular and recursive of operation of the algorithm on z-transform domain. In this paper, the TDLMS which is a extended version of LMS is transformed to STDLMS which has systolic array architecture in two dimensional filter and coefficients update system. The transformed STDLMS is applied for realization of two dimensional ALE. And the ALE performances are evaluated by Max-PlusII of Altera Co.. The simulation results show that the ALE enhances image data which were corrupted by salt-pepper noise and Gaussian noise.

Saccharomyces cerevisiae에서 Clostridium thermocellum Endoglucanase 유전자의 구성적 발현

남수완,정대균,정봉현 동의대학교 기초과학연구소 1998 基礎科學硏究論文集 Vol.8 No.1

To develop an effective and powerful yeast probiotics, Saccharomyces cerevisiae strains producing cellulolytic enzymes were genetically engineered. We constructed two plasmids in which the endoglucanase A gene, celA, of Clostridium thermocellum was connected in frame with ADH1 or GAPDH promoter. These plasmids were transformed into various S. cerevisiae host strains, and then the cell growth, expression level and plasmid stability between the transformed yeast cells were examined in the flask culture. The difference in genetic background of host strains did affect significantly the cell growth and expression level of endoglucanase. Based on the higher levels of cell growth(5.4∼5.9 g-DCW/L) and plasmid stability(79∼85%), three host cells(YNN27, 2805 and SEY2102) and ADH1 promoter were selected as optimal host-vector systems for the constitutive expression of celA. The recombinant yeast produced about 200 unit/L of endoglucanase as a growth-associated manner in the batch fermentation, due to the increased cell growth of 11∼13 g-DCW/L. In addition, 25∼38% and 53∼64% of the endoglucanase activity were detected in the culture medium and periplasmic space, respectively. These results indicate that the signal sequence of celA functioned well in S. cerevisiae cells and the recombinant yeast cells can be employed for the production of probiotics.

溫泉觀光地의 目的地 選擇要因에 관한 硏究

高東完,金奉元,金裕逸 성균관대학교 생명과학자원연구소 1994 生命資源科學硏究 Vol.1 No.2

The purpose of this study was to examine factors of destination choice for hot spring resorts in Korea. Data were collected by questionnaire survey in January 1994, at three typical hot spring resorts : Suanbo, Paikam, and Chuksan. A total of 331 questionnaries were completed by vistiors of three survey sites. The findings of this study were summarized as follows : The seven factors of destnation choice was extracted by factor analysis : 1) the quality of hot spring water, 2) appendant facilites, 3) crowding and cleanness, 4) vicinity tourist area, 5) accessibility and cost, 6) recommendation from friends, 7) popularity. In conclusion, by evaluating the factors, first, endogenous character of resort(e.g. the quality of hot spring water) is the most prefered factor. Second, the factors of destination choice were closely correlated to the incomes of household. Third, the medical benefit of the hot water should be considered when making up hot spring resort.

한국 학교 수학 교육의 재구성

정완수,박지현,정치봉 순천향대학교 기초과학연구소 1999 순천향자연과학연구 논문집 Vol.5 No.1

본 논문에서는 한국의 초 중등 수학 교육의 변화의 방향을 제시하였다. 수학 교육의 새로운 변화의 필요성과 당위성을 수학의 본질적인 특성에서 살펴보았다. 이러한 수학에 대한 교육적인 전망에서 유도되는 자연스런 수학 교육이 필요로 하는 교수 학습 모형과 계산기 및 컴퓨터 등의 기술공학의 교육적 사용에 대하여 고찰하였다.

대학 입학 학력고사의 생물 문항 분석 연구

정완호,권용주,김영신,봉희근 한국교원대학교 과학교육연구소 1994 청람과학교육연구논총 Vol.4 No.1

Not only in science but also in all subjects, the management of high school curriculum in Korea is received the influence of National Testing for the University Entrance Examination. And this influence has more negative aspects than positive ones. In this view point, this study is to analyze the domains of content, behavior, and context, find out the controversial problems, and make some suggestions for the improvement of the National Testing for the University Entrance Examination. The materials of this study are consist of 372 items in the National Testing for the University Entrance Examination from 1969 to 1992. The tool of this analysis is the "three-dimensional analysis tool of science education" which was set up for this study by means of correcting the fifth NAEP Assessment Frame(NAEP, 1984). To keep the validity of study, "the objectivity of the analysits" was measured before the analysis, and the measured objectivity index of analysits is 90.8%. According to the result of this analysis, in the domain of content many items have been set on the area of "development and genetics" and "structures and functions of organs" and the area of "ecology" is increasing its importance. In the domain of behavior, the items about the knowledge and comprehension covered 70.7% and the items about the science process took only 8.3% in spit of the emphasis in the science curriculum. The domain of value and responsibility of biological science hasn't been treated in the items. This analysis shows the fact that the National Testing for the University Entrance Examination have an influence on the way of the normal management of the curriculum and the achievement of educational objective. In the domain of context, the items of National Testing for the University Entrance Examination pay no attention to the area of context such as technological, social, and individual context. This will lead the science education in high school to ignore important educational function of the problem-solving learning and decision-making and this will inevitably result in the danger of cultivating scientifically illiterate people. On the basis of these analysis, when the National Testing for the and University Entrance Examination is taken into consideration on the aspect of its influence on the high-school curriculum, it should take the following into consideration. First, in the domain of content, it should focus on both the application of the area of bioecological aspect such as 'environmental biology', 'conservation biology', 'behavioral biology' and the area of technoogical aspect such as 'cell biology', 'molecular biology', 'microbiology'. Second, in the domain of behavior, scientific process, the value of science, and the application of science in the technological and social aspects should be considered. Third, in the domain of context, the items about the technological, social, and individual context should be treated. Finally, besides all these suggestions, the introduction of the system for previous problem analysis, the consideration study on the validity, difficulty, and discrimination should be conducted.

새로운 방법에 의한 1,1-R,R'-2,3,4,5-테트라페닐-1-실라사이크로펜타디엔의 합성

주완철,흥장환,최석봉 성균관대학교 기초과학연구소 1988 論文集 Vol.39 No.1

A new synthesis of 1,1-R, R',-2, 3, 4, 5-tetraphenyl-1-silacyclopentadiene was described. It was synthesized from one-pot reaction of 1,4-dilithio-1, 2, 3, 4-tetraphenylbutadiene with R_nSiCl_4-n (n=0, 1, 2), where 1, 4-dilithio-1, 2, 3, 4-tetraphenyl butadiene was prepared from the reaction of diphenyl acetylene and lithium metal in ether solution with good yield (80∼85%).

음운환경을 고려한 음성DB용 단어세트의 설계

김봉완,이용주 圓光大學校 1995 論文集 Vol.30 No.2

Speech database is a indispensable part of speech research. This paper introduces the PBW(Phonetically Balanced Words) set for Korean speech database. To collect a speech database, all possible phonological phenomenon should be included. In addition, PBW set has the properties that it has minimal nember of words and even probability distribution between phonological events. In this paper, we investigate some considerations to construct word set for Korean speech database. We extract PBW set composed of 452 words from 5,000 high-frequency words and it's properties are presented.