• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.265-268
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• 2004

We have developed a highly efficient and stable blue organic electroluminescent device (OLED) based on the blue fluorescent p-bis(p-N,N-diphenyl-aminostyryl)benzene (DSA-Ph) dopant in a morphologically stable high-bandgap host material, 2-methyl-9,10-di(2-naphthyl)anthracene (MADN), which achieved an EL efficiency of 9.7 cd/A and 5.5 lm/W at 20 mA/$cm^2$ and 5.7 V with a Commission Internationale d'Eclairage coordinates of(x = 0.16, y = 0.32). This sky blue device which could also alleviate the problematic current induced quenching at high current achieved a half-decay lifetime ($t_{1\;2}$) of 46,000 h at an initial brightness of 100 cd/$m^2$.

• Fibers and Polymers
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• 제6권3호
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• pp.244-249
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• 2005

enVix is a novel regenerated cellulosic fiber, which is prepared from cellulose diacetate fiber using environmentally friendly manufacturing process. Vat dyeing properties of the enVix were investigated and compared with those ofregular viscose rayon. The enVix exhibited better dyeability than viscose rayon. The colour yields of vat dyes on the enVix were found to be dependent on dyeing temperature as well as the amount of levelling agent and salt. Good build-up and good to excellent fastness properties were obtained on the en Vix fabric.

• Korean Journal of Hydrosciences
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• 제4권
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• pp.81-92
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• 1993

This paper presents a model on the migration characteristics which is developed by using the equations for conservation of mass, momentum, and for lateral stability of the streambed. This model enables prediction of the magnitude the location of near-bank bed scour as well as rates and direction of meander migration in the sine-wave type revers (SWR) of small sinuosity. It is evident from this study that the transverse bed slope factor B' and transverse mass flux factor play significant roles in predicting migration characteristics, and their values of B'=4.0 and $\alpha$= 0.4 seem reasonable. This model will produce a useful quidelines in planning, design, construction, and development of SWR basin projects.

• 한국염색가공학회지
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• 제14권6호
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• pp.328-334
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• 2002

Nylon 6 staple ultramicrofiber(UMF, 0.074) and regular staple fiber (Regular, 2.0d) were annealed at In, 130, 160 and $180^\circ{C}$ under tension free for 10 min and U min. The treated fibers were dyed with Acid Red 18 and Blue n3. They were adjusted at PH 5.0 of dye bath in buffer solution of $CH_3COOH/CH_3/COONa(0.1mo1/1)$. Liquor ratio was kept at 1000:1. Dyeing rate of UMF annealed at $100^\circ{C}$ was decreased, but was increased for regular nylon. Also dye equilibrium of UMF at $100^\circ{C}$ was increased for Acid Red 18, but was decreased for Acid Blue 83. The intensities of X-ray diffraction peaks of UMF increased with increasing annealing temperature. Also the crystallinity of heat-sotted fibers by DSC thermogram was well agreed with the tendency of density Amino end group, moisture regain and water absorbency were decreased with increasing annealing temperature.

• 대한산업공학회지
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• 제12권2호
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• pp.89-99
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• 1986

The study attempts to estimate and evaluate the rates of return on graduate degree holders who major in science and engineering. The model of this study adopts the rate of return method considering unemployment as well as mortality rate. The data are collected by questionnaires and interviews. The results show that the social rate of return(SROR) of bachelors is lower than the rate of return on investment in physical capital which is assumed as a decision criterion of public investment in Korea, but the SROR of Ph.D. holders is balanced. The results also show that the private rates of return (PROR) of all the levels in postgraduate science and engineering education are higher than the private discount rate which is a decision criterion of private investment in Korea. It also indicates that the PROR on investment in graduate education is not likely higher than the SROR because an individual bears high share of the educational costs.

• 전자공학회논문지A
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• 제28A권11호
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• pp.894-901
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• 1991

Contact-type linear image sensors have been fabricated by means of RF glow discharge decomposition method of silane and hydrogen mixtures. The dependences of the electrical and optical properties of these sensor on thickness, RF power, substrate temperature and ambient gas pressure have been investigated. the ITO/i-a-Si:H/Al structure film shows photosensitivity of 0.85 and photocurrent to dark current ratio ($I_{ph}/I_{d}$) of 150 at 5V bias voltage under 200${\mu}W/cm^[2}$ red light intensity. Under 200${\mu}W/cm^[2}$ green light intensity, the ratio is 100. In order to investigate photocarrier transport mechanism and to obtain ${\mu}{\gamma}$ product we have measured the I-V characteristics of these sensors favricated with several different deposition parameters under various light sources. The linear inage sensor for document reading has been operated under reverse bias condition with green light source, resulting in ${\mu}{\gamma}$ product of about 1.5$[\times}10^{-9}cm^{2}$/V.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1992년도 봄 학술발표회 논문집
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• pp.89-94
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• 1992

구조물의 비탄성 지진응답을 예측하기 위하여 수행되는 진동대 실험(Shaking Table Test)과 준정적 실험(Quasic-Static Test)의 각 장점을 조합한 유사동적 실험(Pseudodynamic Test)은 실물 크기 구조물의 비탄성 거동온 파악하는 데 널리 사용되고 있다. 이러한 유사동적 실험에서는 구조물에 변위이력의 정확한 가력 및 측정이 가장 중요하다. 측정된 변위와 계산된 변위의 차를 조절오차(Control Error)라고 하며, 임의의 단계에서 측정된 변위를 조정하므로서 그 다음 단계의 조절오차 및 측정오차(Measurement Error)를 감소시킬 수 있다. 따라서 개선된 유사동적 실험의 알고리즘을 얻을 수 있다.

• 한국조경학회지
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• 제15권1호
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• pp.1-8
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• 1987

최근 인문사회과학은 지역적 특수성과 문화적 배경(context)를 무시하고 법측과 체계(system)을 추구하는 자연과학의 개념을 인간사회에 적용하려는 여러 이론들이 인간의 근본적인 문제를 해결하는데 한계가 있음을 지적하고 있다. 이러한 법치주의에 의한 법인간적인 해석보다는 지역적이고 문화적 상황하에서 인간사회의 문제를 이해하려는 경향이 지금까지 행태(behavior)나 사회구조(social structure system)의 이해를 통해 인간사회를 분석하고 있다. 그 방법론으로는 전체의 맥락(context)이나 주변의 연관관계를 통해 의미를 이해하는 책(text)의 해석(interpretation)의 비유를 그 틀(paradigm)로 하고 있다. 이러한 경향은 예술과 미의 문제도 같은 체계(system)속에서 이해하여 현대의 전통, 문화와 대중으로부터 분리된 예술과 미로부터 전통, 문화, 개인과 생활이 공명할 수 있는 본래의 예술과 미를 찾으려 한다. 본 연구는 이러한 사회문화 이론의 개념을 분석하고 그 원리와 이론의 축면에서 경관(landscape)을 해석하고 경관의 의미(미를 포함한)체계(meaning system)을 분석하여 설계언어(design language)를 찾아내며 이를 설계에 응용할 수 있게 하는 기본적 틀(paradigm)을 제시하고자 한다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2004년도 제5회 정기학술발표대회 논문집
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• pp.451-456
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• 2004

Attitude is very difficult to be measured directly; therefore it must be inferred frrom assumed relationship with observable indicators. In some aspects, behavior represents the attitude of a person about a thing, person or issue. In this paper a tool has been devised to measure the attitude of contractor in ongoing project. However, the tool has been tested in a completed technical school construction project in Nepal. The results show that the tool can reasonably measure the attitude of the contractors and can be helpful for the owners to control the projects.

• 대한전기학회논문지
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• 제41권4호
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• pp.422-432
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• 1992

Previous investigations of redundant manipulators have often focussed on local optimization for redundancy resolution by using the Jacobian pseudoinverse to solve the instantaneous relationship between the joint and end-effector velocities. This paper establishes some new goals for redundancy resolution at position level by using configuration control approach which has been recently developed. Minimum gravity loading, joint limit avoidance, minimum sensitivity, maximum stiffness and minimum impulse are introduced as redundancy resolution goals. These new goals for redundancy resolution allow more efficient utilizations of the redundant joints based on the desired task requirements. Simple computer simulation examples are given for illustration.