• Journal of information and communication convergence engineering
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• 제7권3호
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• pp.392-398
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• 2009

A novel approach is presented to improve the array performance of the alternate mainbeam nulling in a linearly constrained adaptive array processor in coherent environment. The convergence parameters in the linearly constrained LMS algorithm with a unit gain constraint and a null constraint in the direction of the desired signal are adaptively estimated to reduce the error power between the desired signal and the array output in the 2-dimensional convergence parameter space. It is shown that the case for estimating the convergence parameter for the unit gain constraint with that for null constraint fixed performs best. Also, it is observed that the proposed method performs significantly better than conventional methods as the number of coherent interferences increases.

• Journal of applied mathematics & informatics
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• 제16권1_2호
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• pp.1-17
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• 2004

The famous Newton-Kantorovich hypothesis has been used for a long time as a sufficient condition for the convergence of Newton method to a solution of an equation in connection with the Lipschitz continuity of the Frechet-derivative of the operator involved. Using Lipschitz and center-Lipschitz conditions we show that the Newton-Kantorovich hypothesis is weakened. The error bounds obtained under our semilocal convergence result are finer and the information on the location of the solution more precise than the corresponding ones given by the dominating Newton-Kantorovich theorem, and under the same hypotheses/computational cost, since the evaluation of the Lipschitz also requires the evaluation of the center-Lipschitz constant. In the case of local convergence we obtain a larger convergence radius than before. This observation is important in computational mathematics and can be used in connection to projection methods and in the construction of optimum mesh independence refinement strategies.

• 한국수학교육학회지시리즈A:수학교육
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• 제28권2호
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• pp.139-143
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• 1989

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.367-370
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• 2002

CRTs can be improved by means of magnetic quadrupoles. Areas of improvement are convergence, spot shape, image-flatness and space charge compensation.

• Kyungpook Mathematical Journal
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• 제2권1호
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• pp.1-6
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• 1959

• 대한수학회논문집
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• 제2권1호
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• pp.63-69
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• 1987

• 한국융합학회논문지
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• 제8권5호
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• pp.145-153
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• 2017

가상현실을 활용한 공연콘텐츠의 성공사례가 늘어나면서 전 세계적으로 공연 관련 기술과 콘텐츠 산업의 가치성에 대한 관심이 급증되고 있다. 그러나 영상기술을 활용하여 성공을 거둔 <태양의 서커스> 이후 많은 콘텐츠들이 무분별하게 디지털 영상기술을 이용한 공연들을 제작하면서, 미흡한 스토리라인, 공간구성, 공연연출로 인하여 콘텐츠의 완성도 및 다양성이 떨어졌다는 비판적 시각을 받고 있다. 이러한 디지털 영상기술을 활용한 공연은 기존의 공연과는 다른 제작과정 단계의 특징들을 기획 과정부터 철저히 고려하여 제작하여야 한다. 본 연구에서는 가상현실 활용한 공간 구성에 중점을 두고 무대 구성의 시각적 요소, 무대 공간성을 살리는 연출법, 퍼포머의 움직임과 활용성 등으로 나누어 콘텐츠 공간 구성과 연출의 적합성에 대해 사례 분석하였다. 이를 통해 전통무대가 지닌 한계성을 영상의 시 공간 속으로 전이시켰으며, 트랜스미디어의 가능성을 열어주었다.

• 디지털융복합연구
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• 제15권1호
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• pp.11-22
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• 2017

본 연구의 목적은 고령화에 따른 공간변화의 대응방안을 제시하는 것이다. 본 연구의 목적을 달성하기 위해 연구의 방법은 문헌조사 방법을 활용하고, 분석에 있어서는 인구 통계자료를 비교 분석한다. 따라서 본 연구에서는 정치경제학적 공간개념을 바탕으로 고령화와 공간의 현황 및 문제점을 파악하였고, 다음과 같은 5가지의 대응방안을 제시하였다. 첫째, 고령인구격차를 고려한 공간계획 수립, 둘째, 합계출산율 증가와 인구 흡입요인 강화, 셋째, 고령자의 생산활동 참여 증가로 공간의 경제 활력 증대, 넷째, 초고령 도시공간에 대한 지역개발계획 수립 및 시행, 다섯째, 고령화의 공간적 격차 심화에 대비한 공간정책의 전환이 필요하다. 결론적으로 고령화 속도를 늦추면서 동시에 관련 공간정책과 계획들이 미스매칭되지 않도록 공간정책과 계획의 전환이 필요함을 제시하였다. 본 연구는 고령화율이 급격히 증가하고 있는 지역에 대한 공간계획 수립에 기여할 것으로 기대된다.

• 한국환경과학회지
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• 제27권7호
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• pp.519-529
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• 2018

With rapid economic growth, the urban environment has created a problem of human physical and mental illness. In order to solve these problems, urban forests have emerged as a way to mitigate the environmental risks through improving the polluted environment of the city and improve the quality of life. As the urban forests have expanded, the school forests movement has also been taking an important place recently. The study focused on the performance of school forests by comparing the perceptions among teachers and students about their functions. The questionnaire was composed of 4 questions concerning human matters, 10 questions for space recognition, 4 questions for thermal environment, 2 questions for health promotion, and 20 total questions for composition of survey items. The reliability of the school forest function, number of tree planting areas and quantities, the harmony of the planting, and the satisfaction of the school forest were analyzed in the questionnaire conducted by the school members. Although it does not recognize school forests, it has a positive response to the green space that is built outdoors. It is considered that outdoor education and environmental education are sufficient in school forests and green spaces. The results showed that the outdoor green space was more satisfactory when compared with the general school. Teachers and students' preferences were similar to 'seasonal changes' and' trees of various colors and shapes'. The reliability analysis between each item shows that the coefficient for cronbach's ${\alpha}$ was .700 to .834. The purpose of this study is to identify the perception of forest function among school forest members and to utilize them as a basic data in the future.

• Journal of Positioning, Navigation, and Timing
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• 제12권2호
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• pp.91-100
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• 2023

The existing indoor localization method using Wi-Fi fingerprinting has a high collection cost and relatively low accuracy, thus requiring integrated correction of convergence with other technologies. This paper proposes a new method that significantly reduces collection costs compared to existing methods using Wi-Fi fingerprinting. Furthermore, it does not require labeling of data at collection and can estimate pedestrian travel paths even in large indoor spaces. The proposed pedestrian movement path estimation process is as follows. Data collection is accomplished by setting up a feature area near an indoor space intersection, moving through the set feature areas, and then collecting data without labels. The collected data are processed using Kernel Linear Discriminant Analysis (KLDA) and the valley point of the Euclidean distance value between two data is obtained within the feature space of the data. We build learning data by labeling data corresponding to valley points and some nearby data by feature area numbers, and labeling data between valley points and other valley points as path data between each corresponding feature area. Finally, for testing, data are collected randomly through indoor space, KLDA is applied as previous data to build test data, the K-Nearest Neighbor (K-NN) algorithm is applied, and the path of movement of test data is estimated by applying a correction algorithm to estimate only routes that can be reached from the most recently estimated location. The estimation results verified the accuracy by comparing the true paths in indoor space with those estimated by the proposed method and achieved approximately 90.8% and 81.4% accuracy in two experimental spaces, respectively.