• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.8 no.5
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• pp.81-102
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• 1987

마늘$\cdot$양파는 항상 과잉생산이 문제되고 있다. 보도에 의하면, 올해 마늘은 지난해보다 20$\%$, 양파는 10$\%$를 각각 줄여 심어야할 것이라고 한다. 작년산 비축분이 아직도 남아있고 금년에도 과잉생산으로 많은 양이 남아돌 전망이므로 면적을 줄여심지 않으면 가격은 더욱 떨어질 전망이라고 한다. 정부당국의 재배면적 유통예고에 따라 적정면적에 알뜰하게 잘 가꾸어 단위 면적당 수량과 품질을 높여 높은 가격을 받는 것이 상업농시대의 경영안목일 뿐 아니라 수급과 가격의 안정을 도모할 수 있는 지름길이라 판단된다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.07a
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• pp.102-107
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• 2002

최근 국민의 식생활이 향상되면서 신선채소류의 수요가 날로 증대되어 국내 부추의 재배 면적도 '92년 199㏊, '94년 729㏊ '99년 1,073㏊로 꾸준히 재배면적이 증가되고 있으며, 부추의 재배면적 확대와 집중출하 등으로 인한 가격의 등락이 심한 편이어서 부추생산의 안정적 기반을 위해서는 기계화를 통한 생산비 절감, 출하시기 및 출하량 조절을 통해 가격의 안정을 도모해야 한다. (중략)

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.11a
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• pp.543-551
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• 1999

본 연구는 광 전송 시스템에 레이저 다이오드의 안정되고 고정된 출력 파장의 광원을 제공하기 위한 것이다. 레이저 다이오드를 구동하기 위하여 안정된 정전류 회로를 설계하려 했으며, 레이저 다이오드 자체의 온도센서와 TEC(Thermo Electric Cooler)를 이용하여 레이저 다이오드 내부의 온도를 제어하는 온도 제어 회로를 구성하였다. 또한 광 출력에 Wavelength Locker를 이용하였다. 최종적으로 이들을 제어하기 위하여 A/D, D/A 컨버터와 마이크로 프로세서를 사용하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.920-923
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• 2009

본 논문에서는 디커플링 제어를 적용함으로써 간략화된 모터 모델의 파리미터 변화에 대해 최대의 안정성을 가진 PI 제어기를 제안한다. PI 제어기 이득은 시행착오에 의해 각 요소를 줄임으로써 모터 파라미터로부터 직접 획득되며, 카리토노브 방정식은 모터 파라미터에서의 이득 변화를 평가하기 위해 사용되었다. 시스템 극점이 같은 위치에 존재하기 때문에 본 논문에서 제안하는 방법은 빠른 응답을 제공한다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.3
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• pp.57-66
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• 2007

Weaving is defined as the crossing of two or more traffic streams traveling in the same general direction along a significant length of highway without the aid of traffic control devices. Compared with other freeway sections, perturbation is easy to happen at weaving section. Because there are a lot of lane-changing maneuvers at the weaving section, traffic is subject to turbulence in excess of that normally presents on freeway basic section. This turbulence causes operational problems and its impact must be considered. The purpose of this paper is to perform a basic study on flow characteristics by lane, which can be achieved through analyzing breakdown phenomenon in the microscopic approach. The study made use of data derived from the aerial photography for the microscopic analysis. This research produced the 30-second interval data such as flows, speeds, and densities for the macroscopic analysis and derived the vehicular data to draw time-space diagram for the microscopic analysis. The paper analyzed the traffic characteristics using flows, speeds and densities variation and investigated the conditions of breakdown occurrence with the time-space diagrams. The breakdown phenomenon was identified at weaving section and the propagation from free flow to synchronized flow was observed in this study. In the future, the findings help develop the traffic operational algorithm to manage the traffic congestion under ubiquitous circumstance since the conditions of breakdown Phenomenon can be understood more.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.975-978
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• 2003

본 논문에서는 주변의 잡음에 의해 통신 환경이 나쁜 시스템에서 통신의 안정성과 고속성과 원거리 통신의 구현을 중점으로 연구하였다 전동차와 같이 Serial Communication을 이용해 차량사이 통신을 하는 경우 주변의 고전압, 고전류의 잡음에 의해 통신 Packet이 파손될 수 있으며 심지어 통신 모들이 파괴되는 현상도 발생한다. 이를 위해 펄스트랜스 포머를 사용해 Hardware의 보호 뿐아니라 고속의 안정적인 통신을 현 할 수 있다. 이는 펄스트랜스 포머의 특성상 하드웨어적으로 분리된 통신선과 통신모듈로 인한 안정성과 원거리 통신을 실현 하였으며 동기통신을 통한 빠른 속도와 FM0, FM1, Manchester 부호 방식에 의한 빠르고 안정한 통신을 제공하기 때문이다.

• The korean journal of orthodontics
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• v.34 no.6 s.107
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• pp.497-505
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• 2004

The purpose of this study was to evaluate the post-retention stability of the lower incisor axis in Class II division 2 malocclusions. The dental casts and lateral cephalograms from before (T1) and after (T2) orthodontic treatment and long-term post-retention (T3) in 62 Class II division 2 malocclusion cases were included in this study. After several linear and angular measurements at each time were taken, the significance in the amount of change of the lower incisor axis for each gender and extraction versus non-extraction was evaluated. The results showed that the lower incisors that inclined labially during treatment were unstable and relapsed to the original lingual position in Class II division 2 malocclusions (p<0.001). There was no significant difference between extraction and non-extraction groups for the amount of lingual relapse of the lower incisors (p>0.05). There was no significant difference between male and female groups for the axial change of the lower incisors (p>0.05). As a result of multiple regression analysis, the cephalometric measurement best predicting the lower incisor position to the A-Pog line post-retention was pre-treatment L1-Apog(mm) and pre-treatment SNGoMe$(^{\circ})$. Because of the instability of labially inclined lower incisors after orthodontic treatment, the treatment goal should be the pre-treatment incisor axial position.

• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.42-50
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• 1998

Titanium dioxide $(TiO_2)$ thin film samples were prepared by using spray pyrolysis methodology and were by using X-ray photoelectron spectroscopy and X-ray diffraction analysis. It was found that anatase prepared by the hydrolysis of titanium(Ⅳ) oxyacetylacetonate exhibited the largest specific surface area. The particle size increased with increasing temperature, while the thickness decreased. Titanium dioxide $(TiO_2)$ in the anatase form was prepared at $400^{\circ}C$ and the photoconductivity was determined using photocurrent measurements. Photoelectrochemical properties of the $TiO_2$-phthalocyanine system were measured in a three-electrode system. The photocurrent action spectrum in the visible region coincided with intrinsic absorption spectrum of phthalocyanine. The crystal structure of phthalocyanine is considered to be a very important property in the photogeneration phenomena.

• Industry Promotion Research
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• v.5 no.1
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• pp.13-20
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• 2020

This study is about consumer preference of plastic toilets that can provide automatic supply of recycled water. First, the preference for plastic toilet seat design by gender and age group was preferred for gender type C and G for the sex. As the result of the chi-square test, the significance probability is .044 and the significance is P <.0 5. I could confirm that. Age, teens, 40 s, and 50 s or older prefer type C, 20 s and 30 s, but B type is not statistically significant. Second, the differences among the groups of preference for appearance design criteria according to general characteristics were all stable (stable appearance) in gender, age, region, education, and salary, but the chi-square test showed that they were not statistically significant. There was no difference between them. This study has implications for improving competitiveness and productivity by reducing the main production cost by commercializing toilets made of plastic materials.

• Journal of Korea Water Resources Association
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• v.34 no.1
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• pp.57-65
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• 2001

A numerical model for analyzing transcritical flow in open channel is tested to various cases of channel shape. As the numerical models developed for transcritical flow until now mainly focused on the application to only prismatic or hypothetical channels, there are some restrictions to apply the nonprismatic channels. In this study, to verify the accuracy and stability of second-order implicit ENO scheme, the numerical model was applied to the channels which haute the varying channel bed and width. Also the numerical model was applied to unsteady flow as well as steady flow. The study shows that the numerical model provides good accuracy in the calculation of stage and velocity with no numerical oscillation, particularly in the calculation of hydraulic jump and discontinous flow Then the implicit ENO scheme demonstrated good accuracy as a high-resolution scheme and stability as an implicit scheme.