• Journal of Microbiology and Biotechnology
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• 제24권2호
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• pp.144-151
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• 2014

Increasing the gene copy number has been commonly used to enhance the protein expression level in the yeast Pichia pastoris. However, this method has been shown to be effective up to a certain gene copy number, and a further increase of gene dosage can result in a decrease of expression level. Evidences indicate the gene dosage effect is product-dependent, which needs to be determined when expressing a new protein. Here, we describe a direct detection of the gene dosage effect on protein secretion through expressing the enhanced green fluorescent protein (EGFP) gene under the direction of the ${\alpha}$-factor preprosequence in a panel of yeast clones carrying increasing copies of the EGFP gene (from one to six copies). Directly examined under fluorescence microscopy, we found relatively lower levels of EGFP were secreted into the culture medium at one copy and two copies, substantial improvement of secretion appeared at three copies, plateau happened at four and five copies, and an apparent decrease of secretion happened at six copies. The secretion of EGFP being limiting at four and five copies was due to abundant intracellular accumulation of proteins, observed from the fluorescence image of yeast and confirmed by western blotting, which significantly activated the unfolded protein response indicated by the up-regulation of the BiP (the KAR2 gene product) and the protein disulfide isomerase. This study implies that tagging a reporter like GFP to a specific protein would facilitate a direct and rapid determination of the optimal gene copy number for high-yield expression.

• 컴퓨터교육학회논문지
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• 제16권4호
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• pp.1-11
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• 2013

본 연구는 사이버 학습과 면대면 학습의 장점을 결합한 초등 혼합형학습에서 자기결정성 학습동기, 교수실재감, 학습성과(학습만족도, 학습지속의지) 간의 구조 관계를 규명하기 위하여 A기업의 혼합형 수학학습서비스를 이용하는 초등학교 5, 6학년생 1,392명을 대상으로 연구하였다. 분석결과 자기결정성 학습동기가 높은 학습자일수록 학습자가 학습과정에서 인식하는 교수실재감이 높았고, 학습지속의지와 학습만족도도 높았다. 교수실재감은 학습만족도에 영향을 주고, 학습만족도는 학습지속의지에 영향을 주었다. 이에 혼합형 학습환경에서 초등학생의 학습만족도와 학습지속의지를 높이려면 자기결정성 학습동기를 높여주는 전략이 우선 처방되어야 하고, 다음으로 학습과정(학습내용의 구조화와 학습활동)을 효과적으로 설계하여 학생들이 인식하는 교수실재감을 향상시켜야 함을 시사하고 있다.

• 에너지공학
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• 제14권1호
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• pp.46-53
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• 2005

본 논문은 확률적 기법을 적용하여 직접부하제어의 적정한 지원금을 산정하는 새로운 방법론을 제안한다. 직접부하제어의 경제성 분석은 발전기의 고장정지 특성, 직접부하제어 자원의 차단용량 및 차단시간 등을 모두 고려해야 하기 때문에 현실적으로 불가능한 것으로 인식되었다. 따라서 기존의 연구에서는 시나리오 접근법을 사용하여 직접부하제어의 경제성 평가를 수행하였다. 본 논문에서는 몬테카를로 시뮬레이션을 적용하여 직접부하제어의 제어전력량을 확률적으로 추정하고 이를 기반으로 직접부하제어의 지원금을 산정하는 새로운 접근법을 개발하였다. 또한 시뮬레이션의 효율을 향상시키기 위하여 분산감소 기법을 적용하였다. 본 논문에서 제안한 방법론의 유용성을 보이기 위해 IEEE 24-모선 신뢰도 계통에 적용하여 사례연구를 수행하였다.

• 분석과학
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• 제26권5호
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• pp.299-306
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• 2013

죽초액은 대나무 숯 제조시 발생하는 강한 산성을 가진 부산물로 80-90%의 수분과 200 종 이상의 유기화합물로 구성되어 있으며, 일반적으로 토양 질 개선, 식물 생육 조절, 아토피 피부염 개선 및 항균효과 등 피부관련 질환에 널리 활용되고 있다. 본 연구에서는 담양군에서 제조한 죽초액 휘발성성분을 direct analysis (DA)법, head space solid phase microextraction (HS-SPME)법, stir bar sorptive extraction (SBSE)법을 이용하여 GC/MS로 분리하고 동정하였다. 위 세 가지 방법을 이용하여 103 종의 화합물을 검출하였으며, HS-SPME와 SBSE방법에서 페놀류 화합물의 선택적 분석이 가능하였다. 죽초액의 주요한 화합물은 유효한 생리활성 물질로 알려진 cresol, guaiacol, p-ethyl guaiacol, syringol이 분석되었다.

• 융합보안논문지
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• 제24권2호
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• pp.133-140
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• 2024

이용자가 직접 유전체 검사를 의뢰하는 DTC(Direct-to-Consumer) 유전자검사가 확산되고 있다. 수요 확대에 따라 인증제도를 통한 비 의료기관에 검사자격을 부여하고, 검사항목을 확대하였다. 그러나 제약이 적은 국외 사례와 달리 국내 제도에서는 여전히 질병 검사항목은 제외한다. 기존의 비식별 방식은 유전체 정보의 고유성과 가족 공유성에도 영향을 미쳐 충분한 활용 가능성을 보장하지 못한다. 따라서 본 연구는 서비스 활성화 및 검사 항목 확대를 위한 방안으로 분석과정에 완전동형암호를 적용하여 유전체 정보의 유용성을 보장하되, 유출 우려를 최소화한다. 또한 정보주체의 자기결정권 보장을 위해 Opt-out을 기반한 프라이버시 보존 모델을 제안한다. 이는 유전체 정보보호와 활용 가능성 유지를 목표로 하며, 이용자의 의사를 반영한 정보의 활용 가능성을 보장한다.

• 대한간호학회지
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• 제16권3호
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• pp.108-122
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• 1986

Changing concepts of health care, are stimulating the demand for health care, thereby orienting society to health care rights to such an extent that they are deemed as fundamental ones inalienable to man. Concomitantly, qualitative as well as quantative improvement is being sought in the nursing service field. Today, efforts are being made in various areas, especially to qualitatively improve nursing services. A second issue concerns proper staffing. It is important to study staffing, in as much as it continues to be the most persistent and critical problem facing hospital nursing administrators today. It involves quantity, quality, and utilization of nursing personnel. A great deal of attention has been focused on this problem since mid 1930's when nursing services began to be felt as an important segment of hospital operation representing the largest single item of hospital budgets. Traditionally, the determination and allocation of nursing personnel resources has relied heavily on gloval approaches which make use of fixed staff-to-patient ratios. It has long been recognized that these ratios are insensitive to variations between institutions and among individual patients. Therefore, the aim of this thesis is to point to the urgent need for the development of methodology and criteria suited to the reality of Korea. The present research selected one place, the W Christian Hospital, and was conducted over a period 10 days from January, and nurses who were them on duty in their unit. The total num-her of patients surveyed was 1,426 and that of 354. The research represents many variables affecting the direct patient care time using the result from the direct observation method, then using a calculation method to estimate the relationship between the patients care time and selected variables in the hospital setting. The amount of direct patient care time varies with many factors, such 89 the patients age. diagnosis and time in hospital. Differences are also found from hospital, clinic to clinic, ward to ward, and even shift to shift. In this research, the calculation method of estimating the required member of nursing staff is obtained by dividing the time of productive patient care activity(with the time of patient care observed), by the sum of the productive time that each the staff can supply, i.e., 360 minutes, which is obtained by deducting the time for personal activities. The results indicate a substantial difference between the time of productive patient care observed directing and the time of the productive patient care estimated using calculating method. If we know accurately the time of the direct patient care on a shift, there required number of staff members calculated if the proper method can be determinded should be able the time of the direct patient care be estimated by the patient classification system, but this research has shown this system to be in accurate in Korea. There are differences in the recommended time of productive patient care and the required number of nursing staff depending upon which method is used. The calculated result is not very accurate, so more research is needed on the patient classification system.

• Structural Engineering and Mechanics
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• 제73권6호
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• pp.631-640
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• 2020

Using backup plate is one of the most commonly used methods to decrease drilling-induced delamination of composite laminates. It has been shown that, the size of the delamination zone is related to the vertical element of cutting force named as thrust force. Also, direct control of thrust force is not a routine task, because, it depends on both drilling parameters and mechanical properties of the composite laminate. In this research, critical feed rate and thrust force are predicted analytically for delamination initiation in drilling of composite laminates with backup plate. Three common theories, linear elastic fracture mechanics, classical laminated plate and mechanics of oblique cutting, are used to model the problem. Based on the proposed analytical model, the effect of drill radius, chisel edge size, and backup plate size on the critical thrust force and feed rate are investigated. Experimental tests were carried out to prove analytical model.

• 한국대기환경학회지
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• 제25권5호
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• pp.450-458
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• 2009

The range-dependent overlap factor of a lidar system can be determined experimentally if a Raman backscatter signal by molecule is measured in addition to the usually observed elastic backscatter signal, which consists of a molecular component and a particle component. The direct determination of the overlap profile is presented and applied to a lidar measurement according to variation of telescope field-of-view and distance between telescope and transmitting laser. The retrieval of extinction coefficient by Raman method can generate high errors for heights below planetary boundary layer if the overlap effect is ignored. The overlap correction method presented here has been successfully applied to experimental data obtained in Gwangju, Korea.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2002년도 11월 학술대회지
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• pp.205-208
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• 2002

Bimodal speech recognition based on lip reading has been studied as a representative method of speech recognition under noisy environments. There are three integration methods of speech and lip modalities as like direct identification, separate identification and dominant recording. In this paper we evaluate the robustness of lip reading methods under the assumption that lip parameters are estimated with errors. We show that the dominant recording approach is more robust than other methods with lip reading experiments. Also, a measure of lip parameter degradation is proposed. This measure can be used in the determination of weighting values of video information.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.285-288
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• 1996

Iron loss is a possible source of performance deterioration, especially for a torque regulation, in field oriented induction machine. In this paper, study on the model of an induction machine with iron losses, a flux estimation strategy, the design of direct and indirect field oriented controller, a precise torque regulation scheme and the determination of a core lost resistance are discussed. Simulation and experimental results are also included and show the effectiveness of the proposed analysis and the proposed control strategy.