• 한국도서관정보학회지
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• 제36권1호
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• pp.219-236
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• 2005

이 연구는 도시저소득층의 일상적 생활세계를 '정보적 관점'으로 접근하고자 한 질적 연구이다. 자료는 질적 면담과 참여관찰을 통하여 수집, 분석하였으며, 부산, 대구, 대전, 광주 지역의 대도시 저소득계층이 지니고 있는 일상적 정보요구와 정보행태를 밀착 조사하고 분석함으로써, 우리 사회의 소수자들이 당면해 있는 정보빈곤의 실태와 이러한 현상을 초래하는 제반 요인을 파악하고자 하였다. 구체적으로 이 연구는 정보빈곤 현상과 정보행태의 소극성 간의 상관관계를 검증하기 위하여 일상적 고민의 유형과 대처 방법상의 특성: 일상적 정보를 얻기 위하여 이용하는 매체의 유형과 특성: 그리고 일상 정보의 탐색과 수집 과정에서 경험하는 각종 장애 등의 범주에 접근하였으며, 소외계층을 위한 공공도서관 서비스 방안을 제시하였다.

• Journal of Microbiology and Biotechnology
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• 제19권9호
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• pp.1028-1033
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• 2009

In this study, the dynamics of living cells (LC) and dead cells (DC) in a laboratory-scale biofilm membrane bioreactor for waste gas treatment was examined. Toluene was used as a model pollutant. The bacterial cells were enumerated as fluoromicroscopic counts during a 140 operating day period using BacLight nucleic acid staining in combination with epifluorescence and confocal laser scanning microscopy (CSLM). Overall, five different phases could be distinguished during the biofilm development: (A) cell attachment, (B) pollutant limitation, (C) biofilm establishment and colonization, (D) colonized biofilm, and (E) biofilm erosion. The bioreactor was operated under different conditions by applying different pollutant concentrations. An optimum toluene removal of 89% was observed at a loading rate of 14.4 kg $m^{-3}d^{-1}$. A direct correlation between the biodegradation rate of the reactor and the dynamics of biofilm development could be demonstrated. This study shows the first description of biofilm development during gaseous toluene degradation in MBR.

• Journal of Ginseng Research
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• 제3권2호
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• pp.156-167
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• 1979

Physiological characteristics of Panax ginseng were reviewed in relation to temperature. According to the old literatures and records of cultivator's experiences it was elucidated that ginseng plants require light but hate high temperature and that the cultural methods were developed to content two characteristics in contradiction. Low temperature (cool climate) during growing season seems (or ginseng to be essential and to escape from the extreme coldness according to air and soil temperature of natural habitat and cultivated area. Optimum temperature of dehiscence (15∼below 20$^{\circ}C$) is a little higher than that of germination (10∼15$^{\circ}C$). Optimum temperature for growing of new buds (18∼20$^{\circ}C$) is similar to that for growing after emergence (17∼21$^{\circ}C$). Dormancy of both matured embryo and new buds is broken at the same temperature (2∼3$^{\circ}C$). It seems reasonable that optimum temperature of photosynthesis (22$^{\circ}C$) is similar to that of growth. Respiration quotients of various organs or of whole plant ranged from 1.7 to 3 incrased with high temperature. Respiratory consumption and oxygen limitation seem to be potential factors to induce decay during dehiscence and germination of seeds and root rot in fields. Research on organ differentiation. photosynthesis, respiration and growth with age is needed for the development of cultivation methods.

• STI Policy Review
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• 제6권1호
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• pp.24-35
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• 2015

This research constructs a data set regarding competition policy through a comprehensive review of previous studies, and performs a meta-analysis to quantitatively assess the price effects of deregulation. A structural econometric model is used to eliminate possible biases from heterogeneity of the studies,such as in publication types and measurement methods. Four types of regulations that deter competition are characterized and three groups of industries are made for drawing practical implications. We fnd that deregulation to promote competition reduces prices by 0.23% and that these estimated price effects are more stable when we control for the publication types and measurement ways. Easing regulations that restrict consumers' choice is shown to be most effcient in promoting competition, lowering prices by 0.7%. This is followed by eliminating the limitation in the number of frms in the industry, with 0.2% price reduction. Overall, the network and service industries are shown to be more responsive to deregulation than the R&D industry. These results could shed light on policy implementation when a pro-competition policy is called for due to restrictive regulations in the corresponding industries.

• 디지털콘텐츠학회 논문지
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• 제18권1호
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• pp.123-132
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• 2017

물리적 디스플레이 기술은 인간이 열망하는 궁극의 디스플레이 기술로서 전 세계가 레이저, 플라즈마 및 반사판 등을 이용한다. 또한 양한 입체 디스플레이 기술개발을 활발하게 진행하고 있으나 광학식으로 인한 주변광의 영향, 밝기 등으로 온전한 물리적 표현에는 한계가 존재한다. 본 논문에서는 기존의 광학식과는 다른 물리적 변형을 이용한 디스플레이 기술을 문화 감성적인 측면의 접근법으로 다가선다. 2차원 평면적인 디지털 사이니즈의 한계를 극복하여 물리적으로 다변화되는 스크린 위에 동적 영상을 투사하여 3차원 실감 입체 이미지를 만들어 낼 수 있는 카멜레온(다변)형 디스플레이 기술을 개발하고 이를 이용한 영상, 전시 및 공연에 적용이 가능한 방법을 연구하고자 한다.

• 천문학회지
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• 제33권3호
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• pp.165-172
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• 2000

A baffle system for an airglow photometer, which will be on board the Korea Sounding Rocket-III(KSR-III), has been designed to suppress strong solar scattered lights from the atmosphere below the earth limb. Basic principles for designing a baffle system, such as determination of baffle dimensions, arrangement of vanes inside a baffle tube, and coating of surfaces, have been reviewed from the literature. By considering the constraints of the payload size of the KSR-III and the incident angle of solar light scattered from the earth limb, we first determined dimensions of a two-stage baffle tube for the airglow photometer. We then calculated positions and heights of vanes to prohibit diffusely reflected lights inside the baffle tube from entering into the photometer. In order to evaluate performance of the designed baffle system, we have developed a ray tracing program using a Monte Carlo method. The program computed attenuation factors of the baffle system on the order of $10^{-6}$ for angles larger than $10^{\circ}$, which satisfies the requirements of the KSR-III airglow experiment. We have also measured the attenuation factors for an engineering model of the baffle system with a simple collimating beam apparatus, and confirmed the attenuation factors up to about $10^{-4}$. Limitation of the apparatus does not allow to make more accurate measurements of the attenuation factors.

• 전자공학회논문지D
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• 제34D권11호
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• pp.90-100
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• 1997

In this paper, we propose a new optical thresold generator as a key-stream genrator for stream cipher systems. The random key-bit stream is generated by a digital generator that is composed of LFSRs and nonlinear ligics. Digital implementatin of a key-stream generator requires large memory to implement programmable tapping points. This memory problem may be overcome easily by using the proposed optical system which has the proberty of 2D parallel processing.To implement hte threshold generator optically, we use conventional twisted nematic type SLMs (LCDs). This proposed system is based on the shadow casting technique for the AND operation between taps and sregister stages. It is also based on the proposed PMRS method for modulo 2 addition. The proposed PMRS method uses the property of light's polarization on LCD and can be implemented optically using one LCD and some mirrors. One of the major advantages of the proosed system is that there is no limitation of the number of the progarmmable tapping points. Therefore, the proposed system can be applied for the 2D encryption system which processes large amounts of data such as 2D images. We verify the proposed system with some simulation.

• 한국게임학회 논문지
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• 제3권1호
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• pp.37-48
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• 2003

최근 들어 게임 사용자들의 욕구가 점점 다양해지고 있지만, 국내 게임제작사들의 신상품개발은 여전히 제작자 관점에서 행해지고 있다. 게임제작사들의 이와 같은 제작자 중심의 상품개발은 거시적으로 게임문화의 다양성을 저해할 뿐 아니라, 게임제작사 자신도 과다경쟁으로 건전한 수익기반을 잃게 될 위험이 크다. 이러한 차원에서 본 연구의 방향을 게임제작사들이 게임사용자 관점에서 사용자들의 욕구를 게임제작에 과학적으로 반영할 수 있는 컨조인트 분석을 소개하는데 중점을 두었다. 컨조인트분석을 직접 한국의 게임사용자들에게 적용하여, 컨조인트 분석을 통해 어떻게 사용자들이 선호하는 게임을 찾아낼 수 있는 가를 보여주었다. 컨조인트 분석결과 한국의 게임 사용자들은 시뮬레이션 게임, RPG 게임, 아케이드 게임의 경우 "다양성 측면"을 가장 중요시하는 것으로 나타났으며, 온라인 게임인 경우 "시나리오"를 가장 중요시하는 것으로 나타났다. 또한 "조작의 간편성"등 사용의 편리성에 대한 욕구도 강한 것으로 나타났다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.470-474
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• 2010

Up until now, power centralized trains have been produced due to the maintenance convenience and comfortableness, but there are some problems, such as limitation of viscosity and maintenance difficulty of railroad due to recently increasing axle mass. In order to improve the problems, power decentralized trains have been developed to improve traction power. In the case of using electrical braking system, it is possible to improve braking friction power. Induction motors have been developed for power decentralized high speed train because of less structural defection, and low maintenance and production cost. However, induction motors have limitations, such as assuring enough power capacity and efficiency with reduced size. PMSM (Permanent magnet synchronous motor) have been newly developed to improve shortcomings of induction motors. The PMSM can be produced small and light weighted. Also if the PMSM and induction motors have the same size and power capacity, the PMSM have better power efficiency. In this pater, the prototype and modified type of PMSM for "High-speed Electric Multiple Unit-400km/h eXperimmen" will be introduced.

• Journal of Plant Biology
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• 제34권4호
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• pp.303-309
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• 1991

Limitation of photosynthesis in detached Chinese cabbage (Brassica campestris L.) leaves was induced by feeding of mannose (25 mM) for 12 h in the light, and changes in the basic thylakoid functions under this condition were investigated. The acid soluble phosphate contend and CO2 uptake rate was decreased by 66% and 67%, respectively. However, the starch content was increased by 24% compared to those of controls. From the fast induction curves of chlorophyll fluorescence, dark level fluorescence (Fo) slightly increased while intermediate plateau fluorescence level (FI) to peak level fluorescence (Fp) transient was significantly decreased with a slight decrease in the Fo-to-FI transient. This data means that reduction of secondary electron acceptor of PSII (QB) might be more severely inhibited than that of primary electron acceptor of PSII (QA) by decrease in phosphate level. The strong decline of (Fv)m//Fm ratio suggests that efficiency of excitation energy capture by PSII was decreased markedly. The quenching of Fo (qO), an indicator of state transition, was also occurred over the slow induction kinetics of chlorophyll fluorescence. From quenching analysis, fluorescence was dominantly quenched by nonphotochemical quenchings (qE+qT). These results showed that the capture and transfer efficiency of excitation energy to PSII reaction center in thylakoid was decreased with the decline of leaf phosphate level, and that the state transition was occurred during the induction of photosynthesis under these conditions.