• 전기전자학회논문지
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• 제22권3호
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• pp.754-758
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• 2018

전력계통에서 해석 하는 방법종류로 정적해석과 동적해석 그리고 온라인 해석과 오프라인 해석으로 나뉜다. 기존의 계통 해석하는 방법으로는 오프라인 정적해석을 이용하며 PSS/E에서도 정적해석을 주로 사용한다. 하지만 우리가 사용하고 있는 실제 계통에서는 실시간으로 값이 변한다. 정확한 해석을 하기 위해 실시간으로 해석이 가능한 온라인 해석과 동적해석이 요구되며 이에 따라 EMS(Energy Management System)에 대한 중요도가 높아지고 있다. 본 논문에서는 다양한 EMS시스템 중에서도 실시간으로 취득 점으로부터 데이터를 받아와 해석 할 수 있는 정적 온라인 해석인 상태추정을 다룰 것이다. 오늘날 DC부하, DC배전망, 신재생에너지 등 다양한 분야에서 DC계통이 확산되고 있다. 이처럼 DC계통에 많은 관심과 이목이 집중되고 있다. 본 논문에서는 DC계통에 접목시킬 수 있는 상태추정에 대한 해석과 사례연구를 통한 사용가능성에 대해 연구하였다.

• International journal of advanced smart convergence
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• 제3권1호
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• pp.20-24
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• 2014

To compare body signal, was designed the F-B function system on the body movement for the comfortable state. To detect subject of the normal state, was decided on the base of physical signal in the body movement. There are to detect the condition of Vision, Vestibular, Somatosensory and CNS. Vision condition was verified a variation of greater average (Vi-${\Phi}_{AVG-AVG}$) was presented slightly greater at $17.424{\pm}9.65$ unit. Vestibular condition was identified a variation of slightly greater average (Ve-${\Phi}_{AVG-AVG}$) was presented at $9.068{\pm}1.478$ unit. Somatosensory condition was checked a variation of smaller average (So-${\Phi}_{AVG-AVG}$) was presented slightly smaller at $2.79{\pm}0.419$ unit. CNS condition was confirmed a variation of diminutive smaller average (C-${\Phi}_{AVG-AVG}$) was presented slightly larger at $0.557{\pm}0.153$ unit. As the model depends on the F-B function system of body movement, average values of these perturbation were computed F-B function comparison data. These systems will be to infer a data algorithm and a data signal processing system for the evaluation of the stability.

• Investigative Magnetic Resonance Imaging
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• 제21권2호
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• pp.91-96
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• 2017

Purpose: To describe technical methods for functional magnetic resonance imaging (fMRI) study with arterial spin labeling (ASL) compared to blood oxygenation level-dependent (BOLD) technique and discuss the potential of ASL for research and clinical practice. Materials and Methods: Task-based (n = 1) and resting-state fMRI (rs-fMRI) (n = 20) were performed using ASL and BOLD techniques. Results of both techniques were compared. Results: For task-based fMRI with finger-tapping, the primary motor cortex of the contralateral frontal lobe and the ipsilateral cerebellum were activated by both BOLD and ASL fMRI. For rs-fMRI of sensorimotor network, functional connectivity showed similar results between BOLD and ASL. Conclusion: ASL technique has potential application in clinical and research fields because all brain perfusion imaging, CBF measurement, and rs-fMRI study can be performed in a single acquisition.

• 전자공학회논문지S
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• 제35S권10호
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• pp.27-33
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• 1998

본 논문에서는 ATM 고속위성 버스트 모뎀에 적합한 동기 요소기술과 개선방안을 사용하여 수신기를 설계하고 AWGN 채널 환경하에서 제반 연동평가를 수행하였다. 또한 프리앰블의 진행에 따라 각 동기부가 동작하는 과정을 평균과 분산특성을 이용하여 제시하고 수렴확률을 통해 복조기의 동작상태와 수렴여부를 판단하였다. 결론적으로 UW 검출기와의 연동을 통해 셀 손실율을 분석한 결과 본 논문에서 구현한 버스트 모드 TDMA 수신기는 보편적으로 요구되는 셀 손실율을 충분히 만족함을 알 수 있었다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.751-755
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• 2007

세계적으로 지적재산권에 대한 권리획득의 중요성이 대두되고 있으며, 이에 따른 국가간, 업체간의 노력이 치열해지고 있다. 국내 건설업체들의 해외시장 개척을 위해서는 원천기술의 확보가 절실하며 이를 위한 국가적 기술개발노력이 필요하다. 국내의 건설기술개발은 매년 지속적으로 증가하는 추세이며, 특히 PQ제도 도입이후 두드러진 증가세를 보이고 있다. 이에 현재 국내 업체들의 건설개술개발실태에 대한 분석과 국가적 기술개발장려제도 및 입찰제도에 대한 비교분석을 통해 국내의 제도적 문제점과 기술개발 실태를 파악하고 이를 토대로 기술개발 촉진과 활용성 향상 방안제시를 위한 연구를 수행 하였다.

• The Journal of Asian Finance, Economics and Business
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• 제6권2호
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• pp.173-181
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• 2019

The paper aims to evaluate the combination of strategies that influence the success of New Technology Based Firms (NTBFs) located in isolated areas with resource constraints. We utilize the Kauffman Firm Survey to construct a subset of 224 firms operating in primary metal manufacturing industries and who are located in non-thriving areas. We focus on the impact of technological strategy, in the form of Inward Technology Licensing (ITL), combined with financial strategy, in the form of increased financial slack. Using a negative binomial-specification technique to model these relations, we find that ITL positively impacts internal innovation in the firm and this relation is strengthened by the presence of greater financial slack. This positive impact of financial slack supports the behavioral theory of the firm rather than agency theory in that financial slack enables further innovation rather than stifling it. This research confirms the importance of resource acquisition, suggesting that entrepreneurs may utilize external sources of knowledge in an effort to build a favorable situation when facing the challenges of location. Finally, by presenting evidence showing the compatibility of a financial strategy with a knowledge strategy (ITL), this study emphasizes the importance to entrepreneurs of choosing the proper combination of varying strategies.

• Nuclear Engineering and Technology
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• 제53권11호
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• pp.3580-3596
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• 2021

An integral test facility, PILLAR, was commissioned, aiming to provide valuable experimental results which can be referenced by system and component designers and used for the performance demonstration of liquid-metal-cooled, passive small modular reactors (SMRs) toward their licensing. The setup was conceptualized by a scaling analysis which allows the vertical arrangements to be conserved from its prototypic reactor, scaled uniformly in the radial direction achieving a flow area reduction of 1/200. Its final design includes several heater rods which simulate the reactor core, and a single heat exchanger representing the steam generators in the prototype. The system behaviors were characterized by its data acquisition system implementing various instruments. In this paper, we present not only a detailed description of the facility components, but also selected experimental results of both steady-state and transient cases. The obtained steady-state test results were utilized for the benchmark of a system code, achieving a capability of accurate simulations with ±3% of maximum deviations. It was followed by qualitative comparisons on the transient test results which indicate that the integral system behaviors in passive LBE-cooled systems are able to be predicted by the code.

• 신재생에너지
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• 제18권1호
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• pp.1-16
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• 2022

Climatic characteristics were described using the LiDAR (Light Detection and Ranging) and the met-mast on Dongbok·Bukchon region. The influences of meteorological conditions on the power performance of wind turbines were presented using the data of Supervisory Control And Data Acquisition (SCADA) and met-mast of the Dongbok·Bukchon Wind Farm (DBWF) located in Jeju Island. The stability was categorized into three parameters (Richardson number, Turbulence intensity, and Wind shear exponent). DBWF was dominant in unstable atmospheric conditions. At wind speeds of 14 m/s or more, the proportion of slightly unstable conditions accounted for more than 50%. A clear difference in the power output of the wind turbine was exhibited in the category of atmospheric stability and turbulence intensity (TI). Particularly, a more sensitive difference in power performance was showed in the rated wind speeds of the wind turbine and wind regime with high TI. When the flow had a high turbulence at low wind speeds and a low turbulence at rated wind speeds, a higher wind energy potential was produced than that in other conditions. Finally, the high-efficiency of the wind farm was confirmed in the slightly unstable atmospheric stability. However, when the unstable state become stronger, the wind farm efficiency was lower than that in the stable state.

• 아시아태평양코퍼스연구
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• 제4권2호
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• pp.1-39
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• 2023

Recent research in usage-based Second Language Acquisition has provided new insights into second language (L2) learners' development of formulaic language (Wulff, 2019). The current study examines the use of phrase-frames, which are recurring sequences of words including one or more variable slots (e.g., it is * that), in written and oral production data from Asian learners of English across four proficiency levels (beginner, low-intermediate, high-intermediate, advanced) and native English speakers. The variability, predictability, and discourse functions of the most frequent 4-word phrase-frames from the written essay and spoken dialogue sub-corpora of the International Corpus Network of Asian Learners of English (ICNALE) were analyzed and then compared across groups and modes. The results revealed that while learners' phrase-frames in writing became more variable and unpredictable as proficiency increased, no clear developmental patterns were found in speaking, although all groups used more fixed and predictable phrase-frames than the reference group. Further, no developmental trajectories in the functions of the most frequent phrase-frames were found in both modes. Additionally, lower-level learners and the reference group used more variable phrase-frames in speaking, whereas advanced-level learners showed more variability in writing. This study contributes to a better understanding of the development of L2 phraseological competence.

• 정보처리학회논문지D
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• 제8D권3호
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• pp.285-294
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• 2001

집배원이 배달순서로 자동구분하기 위하여 요구되는 요소 기술인 4-state 바코드 시스템 개발이 진행중이며, 우편번호, 배달순서코드, 고객정보 등이 적용될 수 있다. 기존의 고객 바코드 판독 시스템은 우편물상의 바코드 심볼로지가 존재하는 판독대상 영역의 기울기가 $\pm 1.47^{\circ}$이고, 심볼의 훼손과 잡영이 없을 경우에 79∼100msec의 속도로 자동구분 정보가 판독된다. 본 논문에서는 판독범위 및 판독성능의 개선을 위하여 CCD(Charge Coupled Device) 센서로부터 획득된 이미지상에서 존재하는 심볼로지 정보의 고속판독 방법을 제시한 것이다. 이 판독방법은 다진(gray) 이미지 바탕면의 경계값(threshold) 기울기 분포를 기준으로 2개의 경계값을 설정하여 판독대상 정보를 획득하였다. 또한, 바코드 심볼로지의 존재 가능성 영역만을 검사하고, 판독대상 영역에서 트래커(tracker)를 탐색하여 심볼로지에 대한 기울기값, 경계값, 좌표값 등을 생성한 후 심볼값이 판독되도록 한 것이다. 판독시험 결과는 심볼로지가 $\pm 45^{\circ}$ 기울어지고, 잡영이 존재할 경우에도 30∼60msec(58,000∼116,000통/시간) 이내에 판독되었다. 우편물 자동구분용 바코드 판독기로써 적용될 경우에 판독속도가 평균 57.25% 이상 개선되고, 판독범위의 확장으로 0.2%미만의 기계적인 오류(이송과정에서의 Jam 발생비율)를 제외할 경우에 거의 99.8% 우편물을 판독하여 자동구분 처리할 수 있게 될 것으로 기대한다.