• 오토저널
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• 제8권1호
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• pp.62-74
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• 1986

The simulation of power cycle and unsteady gas exchange processes in the inlet and exhaust systems of the single-cylinder 2-stroke cycle compression ignition engine was studied in this paper. In power cycle process, the single-zone model proposed by Whitehouse and Way was used, and the convective and radiative heat transfer from cylinder contents to surroundings was considered. To solve the equations for gas exchange process, the generalized method of characteristics including area change, friction, heat transfer and entropy gradients was used. Also with the path line calculation, the entropy change along the path line and the variation of specific heat due to the change of temperature and the composition of cylinder gas were considered. As a result of the simulation, the change of pressure and temperature in the cylinder against the crank angle, the rate of net heat release, and the change of properties at each point in the inlet and exhaust pipe against the crank angle were obtained. The engine performances under various operating conditions were also calculated.

• Ocean and Polar Research
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• 제24권1호
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• pp.1-18
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• 2002

Seasonal variation in global transport calculated from an ocean general circulation model (OGCM) has been assessed through the comparison with observational estimates. The OGCM based on the GFDL MOM1.1 has honzontal grid interval of 10 and 21 verticle levels, and was integrated for 31 years forced by climatological wind stress, freshwater flux, and heat flux with restoring. General features of the world ocean circulation are well reproduced, which include the western boundary currents such as the Kuroshio and the Agulhas Current, the Equatorial Current system, the Antarctic Circumpolar Current, and the Weddell Sea gyres. Also well resolved is the remarkable seasonal variation in the depth-integrated flows in the northern Indian Ocean due to the monsoonal wind. Monthly variation is found to be dominant in the transport of the Antarctic Circumpolar Current through the Drake Passage in accordance with observational estimates. It has been shown that the mid-latitude depth-integrated flows obey the Sverdrup relation, except for some regions such as continental shelf regions where the interaction between stratification and bottom topography is critical.

• 교육시설
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• 제16권4호
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• pp.71-78
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• 2009

After the introduction of the 7th revision of curriculum, educational facilities have been requested to change to face new curriculums and have been planned. But, it is actual condition that researches of curriculum and facilities seem to be insufficient. This research will re-establish in an angle of space-syntax based on existed research for home-base area of variation type in high school according to the 7th curriculum. And the each specific character of home-base area representing each type and strong / weak points of area structure of each home-base will be analyzed. And analysis result with the model of variation type in high school visit the on-the-spot inspection result which leads and comparison and with his interview back it leads and currently there is the objective to the evaluation the variation type in high school home-base which is planned regarding the suitable in real use. Each case to the school I visited the scene, not all high schools applied the 7th curriculum courses. Therefore, it is also home-base space capabilities were not being properly utilize. According to 7th curriculum, one of Hall-type home-base and Room-type home-base can be suitable when integration is higher. However, the way the current operational training, it is the best that Distributed-type home-base needs to be included in each curriculum block.

• The Plant Pathology Journal
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• 제16권1호
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• pp.1-8
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• 2000

Worldwide, rice blast, caused by Magnaporthe grisea (Hebert) Barr. (anamorph, Pyricularia grisea Sacc.), is one of the most economically devastating crop diseases. Management of rice blast through the breeding of blast-resistant varieties has had only limited xuccess due to the frequent breakdown of resistance under field conditions (Bonman etal., 1992; Correa-Victoria and Zeigler, 1991; Kiyosawa, 1982). The frequent variation of race in pathogen populations has been proposed as the principal mechanism involved in the loss of resistance (Ou, 1980). Although it is generally accepted that race change in M. grisea occurs in nature, the degree of its variability has been a controversial subject. A number of studies have reported the appearance of new races at extremely high rates (Giatgong and Frederiksen, 1968; Ou and Ayad, 1968; Ou et al., 1970; Ou et al., 1971). Various potential mechanisms, including heterokaryosis (Suzuki, 1965), parasexual recombination (Genovesi and Magill, 1976), and aneuploidy (Kameswar Row et al., 1985; Ou, 1980), have been proposed to explain frequent race changes. In contrast, other studies have shown that although race change could occur, its frequency was much lower than that predicted by earlier studies (Bonman et al., 1987; Latterell and Rossi, 1986; Marchetti et al., 1976). Although questions about the frequency of race changes in M. grisea remain unanswered, the application of molecular genetic tools to study the fungus, ranging from its genes controlling host specificity to its population sturctures and dynamics, have begun to provide new insights into the potential mechanisms underlying race variation. In this review we aim to provide an overview on (a) the molecular basis of host specificity of M. grisea, (b) the population structure and dynamics of rice pathogens, and (c) the nature and mechanisms of genetic changes underpinning virulence variation in M. grisea.

• 한국미생물·생명공학회지
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• 제25권3호
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• pp.240-247
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• 1997

Bacillary is the most common form of H. pylori observed during human infection. However, it is known that the morphology change of H. pylori from bacillary to coccoid can be occurred with a response to the environmental stresses such as the nutrient depletion, accumulation of toxic metabolites, pH alteration, and exposure to antimicrobial agents. The coccoid form of H. pylori, which is viable but non-culturable in vitro, seems to be the major cause of antibiotic resistancy and high reinfectability of H. pylori. In this regard, we studied the environmental factors that can induce the morphological change in vitro of H. pylori, and the change of fatty acid composition of plasma membrane. The morphological change from bacillary to coccoid could be observed with the depletion of nutrients, pH variation and reactive oxygen species added in the culture media. This morphologic conversion was paralleled by a dramatic decrease in unsaturated fatty acids and an increase in saturated fattv acids of plasma membrane. The change in composition of membrane fatty acid seems to be a kind of protection mechanism of H. pylori against these environmental stresses.

• 대한인간공학회지
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• 제21권1호
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• pp.33-49
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• 2002

With the wide range of movement, the movement of neck accompanies the body surface change of neck and shoulders. And neck corresponds to the collar of garment, meaning that the body surface change of this part affects the construction of patterns for collars. So the purpose of this study was to manifest the changes of body surface in the neck and shoulder accompanied with the movement of the neck and to draw up the facts worth consideration when constructing the collar pattern. In this study, the draft of body surface of neck and shoulder was drawn up by gypsum method according to the 5 movements (standing at attention, neck bending - front, back, right, left). The length of body surface was measured and analyzed by ANOVA, post hoc test, correlation and regression analysis using SPSS 10.0 for Windows. The variation of the surface of neck was remarkable in the vertical lines than the horizontal ones. So the height of collar should be established considering the range of movement of the neck. It was the raising amount of c.f(center front) of neck and girth of neckbase (back) that were proved to have significantly varied after movement. With correlation analysis done, in every movement, the raising amount of side and the girth of neckbase had remarkably positive relation. The movement of the neck accompanied the variation of body surface in the shoulder as well. It was the part of scapula and side of neckbase that the variation was notable, suggesting that the surplus is needed in these parts.

• 한국수자원학회논문집
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• 제51권7호
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• pp.585-597
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• 2018

본 연구는 미래기후변화에 따른 청미천 유역의 향후 수질 변화를 검토하고, 최적관리기법으로의 접근을 이용한 비점오염물질 저감 대책의 유효성을 살펴보는 것을 목적으로 수행되었다. 기후변화에 따른 미래 수문 및 수질변수의 변화를 살펴보기 위하여 Soil and Water Assessment Tool(SWAT) 모형을 이용하였으며, SWAT 모형의 매개변수는 SWAT-CUP을 이용하여 보정하였다. 구축된 Representative Concentration Pathway(RCP) 시나리오 중 RCP 4.5 및 8.5 두 개 시나리오를 이용하여 미래 기후를 고려하였다. 모의 결과로부터 기후 변화가 심화될수록 강우 및 비점오염물질의 유출이 증가하는 것으로 예측되었다. 또한 적절한 최적관리기법을 통해 비점오염물질의 총량뿐만 아니라 시간에 따른 변동성도 함께 효과적으로 저감될 수 있는 것으로 판단된다.

• 응용통계연구
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• 제27권3호
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• pp.387-396
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• 2014

GDP갭(gap)이란 잠재GDP와 실제GDP의 격차로서 산출갭(Output gap)이라고도 한다. 잠재GDP는 노동, 자본 등 생산요소를 완전히 활용하여 달성할 수 있는 최대GDP라고 정의할 수 있다. GDP갭은 수요-공급간 불균형을 의미한다고 할 수 있으며 이러한 특성 때문에 물가 및 고용안정을 추구하는 중앙은행들은 정책수행과정에서 GDP갭을 중요한 정보변수로 활용하고 있다. 본 연구에서는 우리나라의 GDP갭을 그간 선행연구에서 사용하였던 필터링 방법에 의해 분해함으로써 GDP갭 변동을 야기하는 주요 요인이 무엇인지 살펴보았다. Fox 등 (2003)와 Fox와 Zurlinden (2006)에서 사용되었던 Super Smoother 알고리즘을 이용하여 우리나라의 명목GDP갭을 분해해 본 결과 이론적인 설명에 부합하는 것으로 나타났다. 명목GDP갭률 변동의 상당부분은 잔차인 총요소생산성으로 설명됨을 알 수 있었는데, 이는 최근들어 급격한 기술변화 및 환경변화 등 생산성 변화가 GDP변동에 큰 영향을 주고 있음을 의미한다. 다른 나라의 경우와 마찬가지로 국내물가의 영향력도 높은 것으로 나타났지만 대외 의존도가 높은 우리 경제의 특성상 교역조건의 변동 역시 상대적으로 명목GDP 움직임에 큰 영향을 주고 있는 것으로 분석되었다.

• 한국실내디자인학회논문집
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• 제15권4호
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• pp.123-128
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• 2006

The purpose of the research is to estimate the amount of a color image reaction variation by changing areas in order to design the method to reduce an error about the color sample when it is applied in the real situation. The summary of the results acquired in this research is as followed. (1) With fixed observing distance of 1m, we observed that the value and chroma of each color object became higher as sight angle was increased as $2^{\circ},\;10^{\circ},\;and\;30^{\circ}$, even though the variation ratio was different. (2) With fixed sight angle of 10, we observed that the value and chroma of each color object becane higher as observing distance was changed from 1m to 3.3m, even though the variation ratio was different. (3) With same area, we observed that the values and chromas of each color object in the conditions of $1m-30^{\circ}\;and\;3.3m-10^{\circ}$ were almost same. (4) When the area became larger, the subjects tended to feel that colors were bright and clear with the increase of tone. In all the colors, the variation of a color reaction in chroma is higher than those in value. In future, we can observe the limit in applying to colors in the architecture by identifying the tendency of the color change according to the area change qualitatively.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 추계학술대회
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• pp.251-254
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• 2018

주변 환경 변화에 따라 무선 수신 신호가 변화되는 현상을 활용한 Internet of Things(IoT) 시스템에 대한 연구가 활발히 진행되고 있다. 본 논문에서는 고정된 송수신기 간 주기적 신호 교환 시, 수신 신호가 주변 온도 변화에 따라 변화함을 증명하고, 수신 신호 변화를 활용한 화재 감지 기법을 제안한다. 제안 기법은 수신 신호 변화 감지부와 수신기 내부 온도 감지부로 구성되며, 수신기 내부 온도 감지부는 무선 채널 환경 변화에 따른 수신 신호 변화를 화재 발생으로 감지됨을 방지한다. 제안 기법은 화재 감지를 위해 별도의 장치 추가 없이 기존 수신기에 소프트웨어 개선을 통해 지원가능하다는 장점을 지닌다.