• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.864-870
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• 2005

Hydraulic excavators have been popular devices in construction field because of its multi-workings and economic efficiency. The mathematical models of excavators have many nonlinearities because of nonlinear opening characteristics and dead zone of main control valve, oil temperature variation, etc. The objective of this paper is to develop a simulator for hydraulic excavator using AMESim. Components and whole circuit are expressed graphically. Parameters and nonlinear characteristics are inputted in text style. From the simulation results, fixed spring stiffness of MCV can't satisfy accuracy of spool displacement under whole P-Q diagrams. Closed loop type MCV containing proportional gain is proposed in this paper that can reduce displacement error. The ability of closed loop MCV is verified through comparing with normal type MCV using AMESim simulator. The simulator can be used to forecastexcavator behavior when new components, new mechanical attachments, hydraulic circuit changes, and new control algorithm are applied. The simulator could be a kind of development platform for various new excavators.

• 한국농촌건축학회논문집
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• 제13권2호
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• pp.9-21
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• 2011

This study aims to examine and research the characteristics of apartment landscape at the street from a view that apartments are the major element of a cityscape and many apartments form a street today. Then, the subjects of this study were three sections consisting of streets in Namak New Town and the results were as follows. A streetscape is necessary to have identity under the unity(context) of parts which orient to "one as a whole". However, the subject apartments were not united(contextual) in layouts, roofs, and walls, whereas their facades appeared too united(contextual). Accordingly, to make a united(contextual) streetscape, the wall located in a boundary(a buffer zone) with public space which consists of a streetscape, building layout, building height, and roof forms need a design guideline which can have unity as a whole to connect with architectural design. On the other hand, the facade which was found too uniform should have a more active design guideline to elicit identity at unity.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 춘계학술발표대회 논문집
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• pp.336-341
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• 2008

For the last half a century, Korea has been experienced rapid economic growth and industrialization development, however they cause serious problems that environment pollution and energy shortage are appeared, and the biggest problem that we are now confronted are required solutions through all over the world. Now, Korea's energy consumption is the 10th in the whole world. Among them, energy for buildings, about 25% in the whole Energy which spend in Korea, is very serious. Especially, the energy consumption of school buildings which have heating & cooling system according to improvements of educational environment are rapidly increasing. These features are explicit in the University, Because it has lots of colleges and facilities for lecture, experiment, and research. Especially, electric power consumption account for 75 percent of energy consumption in educational institutions. Accordingly, it is important to understand and analyze the pattern of electricity energy consumption which is used. This study attempts to appoint the place which is one of university and to investigate the characteristics of energy consumption like electricity, gas, oil.

• Journal of Korean Vacuum Science & Technology
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• 제6권3호
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• pp.126-132
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• 2002

The origin of image-sticking in metal-insulator-metal type thin-film diode liquid crystal displays(TFD-LCDs) is the asymmetric current-voltage(I-V) characteristic of TFD element. We developed that TFD-LCDs have reduced-image-sticking. Tantalum pentoxide(Ta$_2$O$\sub$5/) is a candidate for use in metal-insulator-metal(MIM) capacitors in switching devices for active-matrix liquid crystal displays(AM-LCDs). High quality Ta$_2$O$\sub$5/ thin films have been obtained from anodizing method. We fabricated a TFD element using Ta$_2$O$\sub$5/ films which had perfect current-voltage symmetry characteristics. We applied novel process technologies which were postannealed whole TFD element instead of conventional annealing to the fabrication. One-Time Post-Annealing(OPTA) heat treatment process was introduced to reduce the asymmetry and shift of the I-V characteristics, respectively. OPTA means that the whole layers of lower metal, insulator, and upper metal are annealed at one time. Futhermore, in this paper, we discussed the effects of top-electrode metals and annealing conditions.

• 한국공간구조학회논문집
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• 제6권3호
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• pp.51-57
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• 2006

본 연구의 목적은 한국건축프로젝트의 경영적 특성을 파악하는데 있다. 본문은 건축프로젝트의 주요 세 요소인 디자인, 건설, 유지관리의 프로세스 질 관리에 영향을 미치는 요소들을 조사한다. 설문조사는 건축관련 대학원생 및 교수, 설계자, 시공자들의 건축프로젝트에 있어서 프로세스 질 관리에 대한 상이한 시각을 보여주고 있다. 이러한 요소들을 분석함으로써 현재 국내의 질 관리 시스템과 프로그램 내용을 교정하고 개선하는데 도움이 될 것이다. 프로세스 질 관리에 있어서 여러 요소 중 설계자와의 협조가 가장 주요 요소로써 부각되었다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.248-251
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• 2000

The fabrication and characteristics of HTS race-track type field coil for generators was carried out. Field coils are composed of 3 pancake coils wound by 37-filamental Bi-2223/Ag-alloy tapes. The winding machine is horizontal type. The critical currents (I$_c$) of the superconducting tapes were measured with variation of bending strain and external magnetic fields. I$_c$ of both whole field coils and 3 pancake coils were measured as a function of temperature. At 77K under the self-field, I$_c$ of whole field coils was 12A, while in the case of middle pancake coil, I$_c$ was 15A. The distribution of magnetic field B was obtained, using 3-D FEM. Our simulation showed that maximums of B${\bot}$A in x-y plane were locally distributed in both the upper and the lower coils. In addition, the fabrication processes and the characteristics of field coil are described.

• Journal of Veterinary Science
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• 제22권6호
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• pp.66.1-66.9
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• 2021

Background: Maedi/Visna virus (MVV) is a contagious viral pathogen that causes considerable economic losses to the sheep industry worldwide. Objectives: In China, MVV has been detected in several regions, but its molecular characteristics and genetic variations were not thoroughly investigated. Methods: Therefore, in this study, we conducted next-generation sequencing on an MVV strain obtained from northwest China to reveal its genetic evolution via phylogenetic analysis. Results: A MVV strain obtained from Inner Mongolia (NM) of China was identified. Sequence analysis indicated that its whole-genome length is 9193 bp. Homology comparison of nucleotides between the NM strain and reference strains showed that the sequence homology of gag and env were 77.1%-86.8% and 67.7%-75.5%, respectively. Phylogenetic analysis revealed that the NM strain was closely related to the reference strains isolated from America, which belong to the A2 type. Notably, there were 5 amino acid insertions in variable region 4 and a highly variable motif at the C-terminal of the surface glycoprotein (SU5). Conclusions: The present study is the first to show the whole-genome sequence of an MVV obtained from China. The detailed analyses provide essential information for understanding the genetic characteristics of MVV, and the results enrich the MVV library.

• 한국음향학회지
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• 제1권1호
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• pp.82-91
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• 1982

To analyze the characteristics of engine exhaust mufflers by the acoustic theory is necessary for understanding the action of mufflers and for designing the mufflers. In many cases, the " Transmission Loss" is used in the analysis, but TL is not suitable for above purposes. In this paper the characteristics of the mufflers is analyzed by means of the four terminal constants of whole muffler system. After some approximation, the characteristics of engine exhaust mufflers is shown by the "D" in the four terminal constants. 20log│D│ can be easily constructed with the characteristics of each element of the muffler system. The analysis is done under the conditions of no loss and no gas-flow, so the result is approximate. But it is very useful for understanding the characteristics of the muffler system or each element of the system and for designing the muffler system.

• Asian-Australasian Journal of Animal Sciences
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• 제17권10호
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• pp.1383-1389
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• 2004

The nutritive value and utilization of whole crop rice silage (WCRS), Hamasari, at yellow mature stage was determined by three studies. In first study, chemical composition, in vivo digestibility and metabolizable energy (ME) content of WCRS was determined by Holstein steers. WCRS contains 6.23% CP, its digestibility is 48.4% and estimated TDN is 56.4%. Its ME content was 1.91 Mcal/kg DM. Gross energy (GE) retention (% of GE intake) in steers is only 22.7% most of which was lost through feces (44.7% of GE intake). It takes 81 minutes to chew a kg of WCRS by steers. In another study, the effect of Hamasari at yellow mature stage at three stages of lactation (early, mid and late lactation) and two levels of concentrate (40 or 60%) on voluntary intake, ME content and ME intake, milk yield and composition using lactating Holstein dairy cows were investigated. Total intake increased with the concentrate level in early and mid lactation, but was similar irrespective of concentrate level in late lactation. WCRS intake was higher with 40% concentrate level than with 60% concentrate. ME intake by cows increased with the concentrate level and WCRS in early lactating cows with 40% concentrate can support only 90% of the ME requirement. Milk production in accordance with ME intake increased with the increase in concentrate level in early and mid lactating cows but was similar in late lactating cows irrespective of concentrate level. Fat and protein percent of milk in mid and late lactating cows were higher with for 60% concentrate than 40%, but reverse was in early lactating cows. Solids-not-fat was higher with for 60% concentrate than 40% concentrate. Finally in situ degradability of botanical fractions such as leaf, stem, head and whole WCRS, Hamasari at yellow mature stage was incubated from 0 to 96 h in Holstein steers to determine DM and N degradability characteristics of botanical fractions and whole WCRS. Both DM and N solubility, rate of degradation and effective degradability of leaf of silage was lower, but slowly degradable fraction was higher compared to stem and head. Solubility of DM and N of stem was higher than other fractions. The 48 h degradability, effective degradability and rate of degradation of leaf were always lower than stem or head. In conclusion, voluntary intake of silage ranged from 5 to 12 kg/d and was higher with low levels of concentrate, but milk yield was higher with high levels of concentrate. Fat corrected milk yield ranged from 19 to 37 kg per day. For consistency of milk, early lactating cows should not be allowed more than 40% whole crop rice silage in the diet, but late lactating cows may be allowed 60% whole crop rice silage.

• 한국식품조리과학회지
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• 제21권6호통권90호
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• pp.919-926
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• 2005

본 연구에서는 12시간 발아시킨 신팔달 2호 콩분말을 첨가하였을 때의 반죽특성과 제면특성을 살펴보았다. 발아콩분말을 첨가한 반죽의 호화특성은 발아콩분말 첨가량이 증가할수록 호화점도가 감소하였으며 $3\%$ 소금을 첨가한 반죽에서는 발아콩분말을 $8\%$ 첨가했을때까지 점도가 높았으나 그 이후에는 소금 무첨가군보다 낮은 경향을 나타내었다. Mixograph로 측정한 반죽의 점탄성도 발아콩분말 첨가량이 증가할수록 감소하였으나 $3\%$ 소금을 첨가한 반죽이 소금 무첨가군보다 높게 나타났다. 생면의 신장도를 측정한 결과 발아콩 분말 $8\%$ 첨가군이 치고의 신장도를 나타내었으며 조리면의 무게과 부피증가율은 발아콩분말 $4\%$ 첨가군에서 가장 높았다. 조리액의 탁도는 발아콩분말 $16\%$ 첨가군이 0.57로 측정되어 고형분의 용출이 가장 많은 것으로 나타났다. 생면 제조시 발아콩분말의 영향은 첨가량이 증가할수록 L값은 지속적으로 감소하였으며 a값은 (-)값이, b값은 (+)값이 증가하여 greenish yellow의 색상을 나타내었다. 조리면의 색도는 생면보다 낮은 값을 나타내었으나 같은 경향을 보였다. 발아콩분말의 첨가량이 증가하면서 생면의 hardness와 cohesiveness, springiness, gumminess 및 brittleness는 증가하였으나 조리면에서는 hardness, gumminess 및 brittleness가 감소하였다. 조리면의 관능검사 결과 발아콩분말 첨가량이 증가할수록 고소한 맛과 냄새는 유의적으로 증가하였고 hardness와 chewiness는 첨가군간에 유의적인 차이가 없는 것으로 나탸났다.