• Title/Summary/Keyword: used shortening

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A Study on the Single Crystal Growth of InGaAsP/GaAs by Vertical LPE System (수직형 LPE 장치에 의한 InGaAsP/GaAs 단결성 성장에 관한 연구)

  • 홍창희;조호성;황상구;오종환;예병덕;박윤호
    • Journal of the Korean Institute of Navigation
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    • v.16 no.2
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    • pp.21-27
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    • 1992
  • Shortening the lasing wavelength(particularly below infrared ; the visible region) of laser diodes is very attractive because it can provide a wide range of applications in the fields of optical information, measurement, sensor, the development of medical instrument, and optical communication through plastic fibers. According to the recent researches on the field, InGaAsP/GaAs was suggested as a material for red-light laser. In this study, in order to grow InGaAsP/GaAs epitaxial layer on InGaAsP/GaAs by LPE, we used GaP and InP two phase solution technique for 670nm and 780 nm region, respectively. Through the X-ray diffraction measurement for the epitaxial layer grown from the experiments, we found that the lattice mismatch of $In_{0.46}Ga_{0.54}As_{0.07}P_{0.93}$/GaAs and $In_{0.19}Ga_{0.81}As_{0.62}P_{0.38}$/GaAs was about +0.3% and +0.1%, respectively.

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Housing optimal design researches of DC-DC converter for HEV (HEV용 DC-DC 컨버터의 하우징 최적 설계 연구)

  • Kim, Yun-Sung;Seo, Ki-Bong;Lee, Yong-Hwa;Baeg, Byung-Dug
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.927_929
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    • 2009
  • This paper reports the case that unitizes heat analysis simulation in housing design of DC-DC converter. Icepak4.3 is used for heat analysis simulation program. 1.5kW prototype is produced with base of finally selected structure through simulation and is compared heating characteristic. Propriety of development application is confirmed through the result, shortening case of development cost and period is introduced.

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Studies on the Effect of Microfine Cellulose upon the Preparation of Prednisolone Tablets by Direct Compression Method (직타법(直打法)에 의(依)한 Prednisolone 정제(錠劑)의 제조(製造)에 있어서 Microfine Cellulose가 미치는 영향(影響)에 관(關)한 연구(硏究))

  • Ok, Su-Jung;Yong, Jae-Ick
    • Journal of Pharmaceutical Investigation
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    • v.5 no.3
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    • pp.58-65
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    • 1975
  • In the preparation of prednisolone tablets, when microfine cellulose$(Elcema^{\circledR})$ was used as diluents, stability and physical characteristics of prednisolone tablets are as follows; 1. Weight of the plain $Elcema^{\circledR}$ tablets increased by 75% of relative humidity and hardness was weakend, but the temperature $(60^{\circ}C)$ caused no change of thickness and decreased the weight and hardness. 2. In experimental tableting of prednisolone tablets, the addition of $Elcema^{\circledR}$ caused no difficulty in direct compression method, and the shortening of the disintegration time and increase of the hardness were satisfactory. 3. Dissolution rate test exhibited the result similiar to disintegration test. 4. In the comparison test of $Elcema^{\circledR}$ and $Avicel^{\circledR}$ as adjuvants the physical constants of prednisolone tablets showed nearly a similar tendency.

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Systematization of Module Design Principle for Recycling (자원 재활용을 위한 모듈 설계 원칙의 체계화)

  • 목학수;양태일
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.11a
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    • pp.969-971
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    • 2000
  • In this paper, shortening of product life cycle and wide disposal of consumer product have given rise to many environmental problems, it needs to propose module design principle for saving of disassembly cost and reusing of used part and subassembly. To analyze characteristics of module for recycling, materials and function of part and subassembly must be classified. In disassembly process, a unit operation can be grasped for disassembly function, worker, tool and sorting process. As a result of applying module design principle, simpler structure and reduced structural interference can be realized for product structure. For disassembly, simpler disassembly and quicker disassembly can be obtained for recycling.

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A Foundation Study on the Selection of Bearing Lubrication Conditions in High-speed Spindle (초고속 스핀들의 윤활조건 선정을 위한 기초 연구)

  • Ahn, Sung Hwan;Lee, Choon Man
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.8 no.1
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    • pp.3-9
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    • 2009
  • Recently, a high speed cutting is essential requirement to satisfy latest demand of high precision product and machining of hard materials. However heat generation by high speed rotation causes many problems. The machining error and shortening spindle lifetime by thermal stress is typical example. Generation of heat is mostly caused by sliding at the rotor and bearing. For minimization of heat generation at bearing, decision of the condition of proper lubrication is necessary. The thermal study about 40,000rpm spindle by changing the condition of oil-air lubrication method is carried out in this paper. The results of this paper can be used effectively in the decision of oil-air lubrication condition of other types of spindle for machine tools.

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Structural Work Duration Estimation and Analysis of Tower-Type Residential Construction Project

  • Yun, Seok Heon;Kim, Sang Chul
    • Architectural research
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    • v.14 no.3
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    • pp.109-116
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    • 2012
  • In order to shorten construction duration in high-rise project, construction company tried to make various system method toward simplifying construction method and shortening construction duration. Though high-rise tower-type residential project are growing, there are few case study. Then, the data for preliminary schedule planning in high-rise tower-type residential project are rare. This purpose of research shows construction method in structural work in high-rise tower-type residential project, suggests schedule planning in structural work through case studies. The structural work in high-rise tower-type residential project was divided 1) completion of form in lower part and 2) the typical floor under penthouse. The statistical analysis were done in two parts, the data from analysis were used in simulation. Finally, researcher confirmed the difference between real construction duration and the figure from simulation. The results shows that the more construction duration is long, the less ACS's cost is low. It means the effectiveness is increasing in ACS, if the floor number is high.

Outrigger System Design Considerations

  • Choi, Hi Sun;Joseph, Leonard
    • International Journal of High-Rise Buildings
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    • v.1 no.3
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    • pp.237-246
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    • 2012
  • Outrigger systems have been widely used in super tall buildings constructed since the 1980's, eclipsing previously favored tubular frame systems. However, outriggers are not listed as a seismic lateral load resisting system in any code. Design guidelines are not available. The CTBUH formed the Outrigger Working Group to develop the first-ever outrigger system design guide with an historical overview, considerations for outrigger application, effects on building behavior and design recommendations including concerns specific to this structural system such as differential column shortening and construction sequence impacts. Project examples are presented for various outrigger system types, including advancements in their technology. The guide provides a basis for future discussions on this important topic.

Cardiac systolic time intervals and heather index measured by impedance cardiography during postural changes (체위변화시 심장의 수축기 시간간격 및 Heather Index의 변화)

  • 고성경;김창규;김덕원
    • Journal of the Ergonomics Society of Korea
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    • v.11 no.1
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    • pp.67-79
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    • 1992
  • Cardiac systolic time intervals (STLs) and Heather index (HI) were used to access changes in left ventricular function of six male subjects exposed to postural changes,$0^{\circ}C$, ${\pm}2^{\circ}C$, ${\pm}45^{\circ}C$, ${\pm}90^{\circ}C$, Significant prolongation of the pre-ejection period (PEP) and PEP/ LVET ratio, shortening of the left ventricular ejection time (LVET), STI, HI and $1/PEP^{2}$were observed during exposure to both $+45^{\circ}C $ and $+90^{\circ}C $But the values measured during $-45^{\circ}C $ and$-90^{\circ}C $ were reversed. Changes in fluid shift, filling volume, preload, after load and sympathetic activities may account for the observed findings. Early response of cardiac foctions was recorded using impedance cardiography. This method is very simple but accurate. Thus it will be useful in this aerospace and work physiology. In conclusion, STIs appear to provide reliable noninvasive method for examining changes of cardiac function during exposure to postural changes.

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Study of Character Animation to improve Production Efficiency

  • Choi, Chulyoung
    • International journal of advanced smart convergence
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    • v.9 no.2
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    • pp.179-184
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    • 2020
  • Recently, webtoons-based animations have been expanding in Korea, where the role of mobile devices is growing, and media videos such as "YouTube" and "Tik-Tok," which have shorter screening and production cycles than traditional feature films, dramas, and animations, are attracting attention and being enjoyed by public. In order to produce animation content that fits the trend of this shortening video and production cycle, efficiency must be increased not only in story but also in production. Production methods and production technologies need changes to increase efficiency. Animation using motion capture, which is highly production-efficient, is widely used in movies that shows realistic movements, but still has little use in producing cartoon-style animations with exaggerated movements. We analyzed the production method of 2D animation and CG animation and applied the result to CG animation to increase the efficiency of production and production. The methods of production through such experiments are expected to help improve the efficiency of producing animation content that is suitable for the latest trends such as webtoon animation.

BIM Utilization Plan for Schedule Risk Management (공정리스크 관리를 위한 BIM 적용 방안)

  • Lee, Gye-Hyun;Kim, Ju-Hyung;Kim, Jae-Jun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.05a
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    • pp.143-144
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    • 2012
  • A number of construction projects tied to the concerns and decision-making is also very complicated. In addition, more than any other industry, is inherent in many risk factors. In the course of the construction project on risk factors that exist in the early stages of project risk factors to predict in advance and prepare a project by shortening the construction period and project cost as you can to maximize performance. In this study, I proposed risk management processes and how they are used in web-based schedule risk in the process of change management system, and between 3D CAD, 4D CAD taking into account the linkages, risk management strategy process in the BIM environment.

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