• Journal of Biosystems Engineering
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• 제23권2호
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• pp.157-166
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• 1998

In this study. a traveling control system was developed to transfer a machine without an operator in the working zone. The dimension of the system was modelized to design and construct smaller than that of real configuration of a greenhouse. For this system, the fixed path type was used to detect exact position during operating a manless machine. and the X-Y table actuator type to escape a unique path, which had the disadvantage in a fixed path type environment. Based on the results of this research the following conclusions were made : 1. This system used two screws to move toward horizontal direction, and a Plate to reach at any points in the working zone. 2. The software combined the functions of path selection and motor operation to control into one program. The path selection program was a menu driven program written in Visual Basic, and the motor operation program was written in Borland C++ for actuating motors. 3. The path-select mode of the program was used by selecting the desired paths, and the user path-create mode by selecting a random path in the path-selection program. 4. The system proved to be a reliable system for operating a manless machine, since accuracy and precision to reach the positions were less than 1%.

• 한국작물학회지
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• 제19권
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• pp.83-99
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• 1975

우리나라에서의 섬유용 아마의 육종 목표와 관련된 육종상의 기초적 문제를 구명하고 답전작 섬유용 아마육종사 필요한 정보를 얻기 위하여, 도입된 4개품종의 이면교잡 잡종집단에 관하여 개화시까지의 일수, 초장, 경장, 건경중등 양적형질의 유전양식, 유전력 및 그들의 지역적 변이에 관한 시험을 하였다, 그 결과를 요약하면 다음과 같다. 1. 개화시까지의 일수는 짧은 것이 긴것에 대하여 완전 우성으로 나타났다. 2. 초장과 경장은 짧은 것이 긴것에 대하여 부분 우성으로 나타났다. 3. 건경중은 비대립유전자 간의 상호작용으로 분명치 않으나 무거운 것이 가벼운 것에 대하여 열성으로 나타났다. 4. 개화기간, 건경중 및 섬유비율의 유전력은 대체로 높았고 개화일수, 경장 및 섬유중의 유전력은 대체로 높았고 개화일수, 경장 및 섬유중의 유전력은 비교적 낮게 나타났다. 5. 섬유수량과 건경중 그리고 건경중과 초장간에는 높은 정의 상관을 보였다. 6. 섬유수량과 섬유비율, 섬유수량과 개화기간, 초장과 개화기간 중에는 각각 부의 상관이 있었다. 7. 초장($X_1$), 건경중($X_2$) 및 섬유중( $X_3$ ) 의 3개형질을 고려한 선발지수의 이용이 가장 능률적이었으며 이때의 각형질의 선발지수는 0.002$X_1$+0.0047$X_2$+0.0181$X_3$였다. 8. 선발시 고려되는 형질중 유전획득량과 선발효율을 가장 높일 수 있는 형질은 초장이었다. 9. 조사된 형질들은 모두 지역간 차가 현저하고 유전형 대 지역의 교호작용도 유의한 경우가 많았다.

• 한국항행학회논문지
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• 제23권6호
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• pp.589-596
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• 2019

DSRC를 활용한 ITS 시스템이 확산됨에 따라, 더 높은 전송 용량 및 전송 신뢰도를 요구하는 ITS 서비스가 개발되고 있다. 이에 따라, 차량 통신 환경에서 높은 전송 용량 및 신뢰성을 지원하는 한편 기존 무선랜 차량 단말들과의 형평성을 보장하기 위해, IEEE에서는 차세대 차량 통신 표준인 IEEE 802.11bd가 제안되었으며, 표준화가 개발 및 진행 중이다. 특히, 높은 전송 용량 지원을 위해, IEEE 802.11bd에서는 20 MHz 대역을 활용한 전송 동작이 지원 및 반영되었다. 본 논문에서는 기존 무선랜 채널 확장 방법을 활용하면서도 차량 통신 환경에서의 기존 단말과의 채널 접근 방법에서의 공정성을 만족하기 위한 채널 접근 방법을 제시한다. 특히, 채널 점유 비율에 따른 주 채널 설정 방법을 통해 기존 단말의 채널 접근 방법과의 공정성을 유지할 수 있다.

• 대한전자공학회논문지
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• 제27권5호
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• pp.747-755
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• 1990

In this paper, we presented a method of constructing a multiplier and an inverse element generator over finite field GF(3**m). We proposed the multiplication method using a descending order arithmetics of mod F(X) to perform the multiplication and mod F(X) arithmetics at the same time. The proposed multiplier is composed of following parts. 1) multiplication part, 2) data assortment generation part and 5) multiplication processing part. Also the inverse element generator is constructed with following parts. 1) multiplier, 2) group of output registers Rs, 3) multiplication and cube selection gate Gl, 4) Ri term sequential selection part. 5) cube processing part and 6) descending order mod F(X) generation part. Especially, the proposed multiplier and inverse element generator give regularity, expansibility and modularity of circuit design.

• Fibers and Polymers
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• 제6권3호
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• pp.186-199
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• 2005

A selection of commercially available poly(ethy1ene terephtha1ate) fibers with different degrees of molecular alignment and crystallinity have been investigated utilizing a wide range of techniques including optical microscopy, infrared spectroscopy together with thermal and wide-angle X-ray diffraction techniques. Annealing experiments showed increased molecular alignment and crystallinity as shown by the increased values of birefringence and melting enthalpies. Crystallinity values determined from thermal analysis, density, unpolarized infrared spectroscopy and X-ray diffraction are compared and discussed in terms of the inherent capabilities and limitations of each measurement technique. The birefringence and refractive index values obtained from optical microscopy are found to decrease with increasing wavelength of light used in the experiments. The wide-angle X-ray diffraction analysis shows that the samples with relatively low orientation possess oriented non-crystalline array of chains whereas those with high molecular orientation possess well defined and oriented crystalline array of chains along the fiber axis direction. X-ray analysis showed increasing crystallite size trend with increasing molecular orientation. SEM images showed micro-cracks on low oriented fiber surfaces becoming smooth on highly oriented fiber surfaces. Excellent bending characteristics were observed with knotted fibers implying relatively easy fabric formation.

• 한국연초학회지
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• 제22권1호
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• pp.25-30
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• 2000

Bacterial wilt(Ralstonia solanacearum) is one of the major diseases of flue-cured tobacco (Nicotiana tabacum L.) in the world. This study was conducted to investigate degree of dominance, selection, and correlation between leaf shape and degree of bacterial wilt resistance in flue-cured tobacco. The degree of disease caused by bacterial wilt was evaluated in parents, F$_1$, F$_2$ and F$_3$ populations of two crosses, BY 4 x NC 95 and BY 4 x Coker 86, in the infected field. The leaf shape index was also measured in parents and F$_2$ population of BY 4 x NC 95. The incidence of bacterial wilt was observed in the middle of June and peaked in late July, when the highest value of pathogen density reached 1.0 x 10$^{6}$ colony forming unit per gram. It was concluded that the inheritance mode of risestance to bacterial wilt in the above two crosses of susceptible and resistant varieties was recessive and polygenic. The resistance to bacterial wilt was significantly correlated with leaf shape in F2 generation of BY 4 x NC 95. But certain plants having narrower leaves were also resistant to bacterial wilt. It is considered that the bacterial wilt resistant lines having narrower leaves could be selected. The selection for bacterial wilt resistance in the F$_2$ population might be effective.

• Journal of the Korean Data and Information Science Society
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• 제17권4호
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• pp.1329-1341
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• 2006

When X and Y have independent gamma distributions, we consider the testing problem for two gamma means. We propose a solution based on a Bayesian model selection procedure to this problem in which no subjective input is considered. The reference prior is derived. Using the derived reference prior, we compute the fractional Bayes factor and the intrinsic Bayes factors. The posterior probability of each model is used as a model selection tool. Simulation study and a real data example are provided.

• Journal of the Korean Data and Information Science Society
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• 제5권1호
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• pp.11-20
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• 1994

In recent years, nonparametric kernel estimation of regresion function are abundant and widely applicable to many areas of statistics. Most of modern researches concerned with the fixed global bandwidth selection which can be used in the estimation of regression function with all the same value for all x. In this paper, we propose a method for selecting locally varing bandwidth based on bootstrap method in kernel estimation of fixed design regression. Performance of proposed bandwidth selection method for finite sample case is conducted via Monte Carlo simulation study.

• 한국조경학회지
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• 제16권3호
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• pp.7-20
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• 1989

^x This paper aims to grasp the basical things of the architectural meaning of Bu - Seok Temple through the background of site selection and the analysis of arrangement change of it. For this purpose, I try to examine the process of folk- belief adhesion of Buddism and Feng - Shui as the choice factor of site when the temple was established, the spatial characters of the changing stage in arrangement. These characters of Bu - seok temple have significance for the basic study on the site selection and the spatial analysis of a mountainous district Temple in Shilla.

• Journal of the Korean Data and Information Science Society
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• 제9권2호
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• pp.179-188
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• 1998

커널형 회귀함수의 추정법 중에서 국소 다항회귀 추정법이 가장 우수한 것으로 알려져 있다. 국소다항회귀 추정법에서도 다른 종류의 커널추정량과 마찬가지로 평활량이 중요한 역할을 한다. 특히 회귀함수가 복잡한 구조를 가질 때 변수평활량(variable band-width)을 사용하는 것이 타당할 것이다. 본 연구에서는 완전자료기저(fully automatic, fully data-driven) 변수평활량 선택법을 제안한다. 이 선택법은 편향과 분산의 예비추정에 필요한 평활량을 교차타당성 방법으로 선택하여 MSE를 추정하고 그 값을 최소화하는 평활량을 택하는 것이다. 제안된 방법의 우수성을 모의실험을 통하여 확인하였다. 그리고 제안된 방법은 자료점이 성긴(sparse)부분에서 생길 수 있는 문제점 즉 X'X의 비정칙성(non-singularity)을 해결할 수 있는 방법이라는 데에도 큰 의미가 있다.