• 한국전자파학회논문지
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• 제19권2호
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• pp.271-279
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• 2008

본 논문에서는 FHSS 방식의 소출력 무선기기와 DSSS 방식의 소출력 무선기기가 동일 주파수 대역에 존재하는 경우 업무간 간섭을 분석하였다. 분석 방법은 몬테 카를로 방법을 이용하여 DSSS 방식의 소출력 무선기기의 불요 방사가 FHSS 방식의 소출력 무선기기에 미치는 영향을 간섭 확률 측면에서 계산하였다. 간섭 시뮬레이션은 DSSS 방식의 소출력 무선기기의 대역폭과 충격 계수에 따른 간섭량을 계산하였고, 전파 모델은 자유 공간으로 가정하였다. 그리고 간섭원과 피간섭원 사이의 거리에 따른 영향을 수신기에서의 BER 측면에서 분석하였다. 간섭 분석 결과, 간섭원의 대역폭보다는 충격 계수가 시스템 양립성에 많은 영향을 주는 것을 확인할 수 있었고, 단일 간섭원과 다중 간섭원이 존재하는 경우 BER 기준을 만족하는 이격 거리를 확인할 수 있었다.

• 대한정형도수물리치료학회지
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• 제21권1호
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• pp.29-35
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• 2015

Background: The purpose of this study was conducted to investigate the effect of incidence of ankle sprains on both leg length inequalities and range of motion of ankle joint in 20's female university students. Methods: 20's female university students were targeting 32 people attending K university in Gwangju. Both leg length inequality was measured using a tape measure, ranges of motion of ankles was measured using a goniometer. Results: The ankle sprain incidence was quite high, with 56.25% (n=18) for the right ankle, 34.38% (n=11) for the left ankle, and 9.38% (n=3) for both. As for the difference between the ankle sprain incidence and both leg length, the average value of the right leg was $83.08{\pm}3.69$, the average value of the left leg was $84.28{\pm}3.27$, making the right leg shorter than the left by 1.2cm with a higher incidence and showing a positive statistical correlation between the two (p<.05). Also showed that there was a negative statistical correlation between ankle sprain incidences and the inversion range of motion spread of the right ankle (p<.05). Conclusion: The incidence of ankle sprains was higher for the larger the difference between both leg length inequality. In addition, the smaller the inversion range of motion spread of the right ankle, the higher the incidence of ankle sprains. Therefore, The evidence suggests that the incidence of ankle sprains can be reduced by recommending stability and efficient exercises that take into consideration the both leg length as well as the ranges of motion of ankle joints.

• 한국주거학회논문집
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• 제18권4호
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• pp.37-48
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• 2007

Purpose of this study is to investigate influence on preference of cohousing (eg. intention to spread and intention to move in cohousing) according to sense of community, especially in housing life by married people residing in Seoul and its outskirts. Research method used for this study was a social survey. Respondents were 214 people by accidential sampling. The collected data were analyzed by SPSS 12.0 program using frequency, mean, average, T-test, one-way Anova, Duncan's Multiple Range test and Chi-square test. Findings of this study were as follows. Most respondents took part in interactive activities with colleagues from the same occupation. They Focused on the issues about health, leisure and hobby. The respondents mainly wanted to have interaction for changing recycling materials and education programs for children and juveniles. Degree of ideal relationships with neighbors, they think, were greeting and chatting as well as communication about issues on child-care, education for children, offense-prevention and safety. Although respondents were interested in community life and in interaction with their neighbors, they did not build up communal society due to lack of a sense of belonging in their living areas. While respondents showed positive response about preference of cohousing, there were difference between intention to spread of cohousing and intention to move in cohousing. As a result of this study, the stronger sense of community in housing life meant the more interests in thoughts to spread and to move in cohousing. Therefore, in order to increase sense of community in cohousing, the plan of various communication programs that enables frequent interaction among neighbors is needed. Also, in order to spread cohousing in Korea, promotion of cohousing community and cognitions about it are the most needed.

• 천문학회보
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• 제38권1호
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• pp.64.1-64.1
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• 2013

The point spread function (PSF) of an optical system is in general defined as a two-dimensional intensity distribution which results from a single point source at infinity. It is an important key for the evaluation of the optical performance of an astronomical telescope. The PSFs of the soft X-ray telescope (SXT) aboard Yohkoh were measured in a wide range of the field-of-view under the in-flight configuration at White Sands Missile Range prior to launching the satellite. It has been known that the SXT PSF has a sharp peak at the core and the intensity drops very fast as it goes distant from the center. Due to the combination of this sharp peak at the PSF core and the effect of undersampling by a large pixel size, a carefully designed method is requested in the examination of the PSF data. The pattern of the SXT PSF is determined by the fitting of a mathematical functional form to the pre-launch experimental data. The elliptical Moffat function has been adopted for the evaluation of the SXT PSF. It is revealed from our study that the SXT PSF shows a peculiar characteristics, and thus a careful consideration on the undersampling effect and also a proper choice of statistics are necessary for the determination of the best fit function of the PSF. Details on the on- and off-axis SXT PSF in the field-of-view will be introduced and discussed in our presentation.

• 신재생에너지
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• 제17권2호
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• pp.1-8
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• 2021

We estimated the price range of electricity transactions under the prosumer system, considering the spread of renewable energy and the prospect of introducing a surplus power trading system between power consumers in Korea. The range (min/max) of power transaction prices was estimated by prosumers and consumers who could purchase electricity from utilities if needed. It is assumed that utilities purchased electricity from prosumers and consumers under a Time-of-Use (TOU) rate, trading at a monthly price. The range of available transaction prices according to the amount of power purchased from utilities and the amount of transaction power was also estimated. The price range that can be traded is expected to vary depending on variables such as the TOU rate, purchased and surplus power, levelized cost of electricity, etc.

• 대한공간정보학회지
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• 제6권1호
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• pp.105-116
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• 1998

임해발전소로부터의 온배수의 확산은 해양환경이나 수산업측면에서 문제가 되고 있다. 온배수의 분포조사는 넓은 지역에 대하여 동시에 이루어져야 하므로 실측조사가 매우 어렵다. Landsat의 센서들 중에는 열적외선파장영역이 있어서 수온의 확산과 분포를 추출해 낼 수 있다. 이 연구에서는 수온분포의 형태를 보다 정확하게 할 목적으로 DN을 스트래칭 한 후 GIS기법을 적용하였다. 따라서 수온분포의 패턴을 광범위한 지역에 대하여 보다 세밀하게 표현할 수 있었으며 경제적으로 온배수의 확산 및 분포를 분석할 수 있었다.

• Journal of International Society for Simulation Surgery
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• 제4권1호
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• pp.21-23
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• 2017

Purpose In this paper, we proposed alternate neighborhood system and reverse spread-direction approach for accurate and fast cellular automata-based image segmentation method. Materials and Methods On the basis of a simple but effective interactive image segmentation technique based on a cellular automaton, we propose an efficient algorithm by using Moore and designed neighborhood system alternately and reversing the direction of the reference pixels for spreading out to the surrounding pixels. Results In our experiments, the GrabCut database were used for evaluation. According to our experimental results, the proposed method allows cellular automata-based image segmentation method to faster while maintaining the segmentation quality. Conclusion Our results proved that proposed method improved accuracy and reduced computation time, and also could be applied to a large range of applications.

• 디지털산업정보학회논문지
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• 제8권3호
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• pp.157-169
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• 2012

As of 2006. 3. the twitter offered in the USA has been one of the propaganda instrument used with ads and politics functioning speedy information diffusion on SNS communicated with others through 140 letters of short messages. and while twitter is using propaganda instrument, it keeps on trying to verify how it has an effect on. So, on the paper, I suggest new simulation model of information diffusion based on probability being able to predict the range of proliferation after it analyze the existing influence and the diffusion force on verification methods. It designed algorithm of verification and algorithm of prediction to use twitter's Open API with Python basement. It proved effectiveness on the model through the analysis to operate the twitter of practical local autonomous entity.

• Journal of Electrical Engineering and Technology
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• 제9권2호
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• pp.771-776
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• 2014

In this paper, an agile programmable chirp spread spectrum generator for wideband frequency-jamming applications from 20 MHz to 3 GHz is proposed. A frequency-mixing architecture using two voltage-controlled oscillators is used to achieve a wideband operating frequency range, and the direct digital synthesizer (DDS)-based chirping method with a two-point modulation technique is employed to provide a programmable and consistent chirp bandwidth. The proposed signal generator provides the various programmable FM signals from 20 MHz to 3 GHz with a modulation bandwidth from 0 to 400 MHz. The prototype successfully demonstrates arbitrary sequential jamming operation with a fast band-to-band hopping time of < 10 ${\mu}sec$.

• 한국군사과학기술학회지
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• 제5권1호
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• pp.37-44
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• 2002

An echo signal in the active sonar using a high frequency is mainly formed of a specular reflection from the surface of an object along with several equivalent scatter inside, which are characterized by the spatial distribution of the highlights on the object. This thesis proposed a model in which the synthesized echo signal can be expressed as a distributed simulated target. The proposed model is obtained after composing a signal based on the movement of highlights relative to the aspect angle from the discontinuous point of an external hull with a strong reflection from a spheroid underwater target. Because the proposed algorithm includes a synthesis of the signals related to the highlight spacial distribution, it can be applied to all kinds of systems used at a short range, and similar results were obtained to the actual measured results of all reflected signals in previous literature referring to the irregular factor application of an envelope.