VR 응용을 위한 쿼드트리기반 이동벡터 분석

김윤호(Kim Yoon-ho) 한국정보기술학회 2007 한국정보기술학회논문지 Vol.5 No.1

In this paper, quadtree-based moving vector analysis scheme is addressed, which is able to use a preprocess so as to analyze a avatar behavior in virtual space. Firstly, moving vector is segmented from background image by using difference image scheme, and secondly, quadtree algorithm is utilized to analyze the binary region. Binarized motion vector is divided into sub-tree and then trace of motion vector is analyzed using center of gravity of moved vector. Some experiments are performed under variation of brightness as well as fixed brightness. Experimental showed this approach can be applied to the virtual space.

RGB 성분을 활용한 색상 속성 차이도 판별 기법

김아림,신용태 한국IT정책경영학회 2018 한국IT정책경영학회 논문지 Vol.10 No.1

Color is a visually important part of computer graphics. However, there are no precise criteria to show the differences between the colors represented by the various expressions. It is possible to express arbitrary color in size and direction by using the concept of vector in three dimensional space. Applying a vector operation to the attributes of a color, the color difference for each attribute can be obtained. In this paper, we describe the method of distinguishing color difference. Further studies on more accurate discrimination techniques to evercome the limitation of color difference will be needed.

움직임 벡터를 이용한 낙상 감지 시스템

김상수(Sang-Soo Kim),김선우(Sun-Woo Kim),최연성(Yeon-Sung Choi) 한국정보전자통신기술학회 2016 한국정보전자통신기술학회논문지 Vol.9 No.1

본 논문에서는 움직임 벡터를 이용한 낙상 감지 시스템에 관해 기술한다. 두드러진 움직임을 위한 가중치 차영상 기법, 움직임 벡터를 이용하여 인간이라고 판단되는 블랍을 검출하고, 추출된 움직임 벡터를 이용하여 낙상 여부를 판단한다. 기존의 영상 기반 낙상 감지 시스템의 경우 특정 방향으로 낙상이 발생하는 경우에만 낙상 감지에 성공하였지만 제안 시스템의 경우 다양한 각도에서 낙상이 발생하여도 상황 판단이 가능하다는 장점이 있다. 실험을 위해서 150개의 상황을 연출하였으며, 약 85% ∼ 97.1% 낙상 상황 판단 성공률을 보였다. In this paper, Author of this article presents a system to ensure the safety of residents in case the residents occurs an fall situation. Author of this article use weighted difference image and motion vector. Proposed system suggested the fall detection algorithm using weighted difference image and motion vector. Fall detection algorithm showed a success rate of 85% ∼ 97.1% through 150 experiments. Proposed algorithm showed a litter higher or similar success rate than the existing camera based system.

외국인직접투자와 경제성장 및 고용간 관계

강기춘 한국산학기술학회 2019 한국산학기술학회논문지 Vol.20 No.12

In this paper, the economic performance of the Jeju Free International City and the Free Economic Zone is investigated using statistical testing and the difference in differences (DID) model with data on foreign direct investment (FDI), gross regional domestic product (GRDP), and employment-to-population ratio (EPR). The relationships among FDI, GRDP, and EPR are also investigated using the panel vector error-correction model on the regional data. The compound average growth rate of actual investment, and the ratio of FDI received to FDI declared in the capital region were higher than in the non-capital region. For the growth and relative volume of FDI received, seven regions out of 16 were found to be low in growth and small in relative volume. The results of statistical testing showed statistically significant differences in some variables, except for two regions, but DID estimates that determine the pure policy effect of zone designation showed statistical insignificance. On the other hand, the explanatory power among the three variables was found to be quite limited, but it was greater in the cities, provinces, and non-capital region. In summary, it is necessary to establish the FDI inducement mechanism so the inflow of FDI can increase GRDP and EPR. 본 논문에서는 제주국제자유도시 및 경제자유구역의 경제적 성과를 외국인직접투자(FDI), 지역내총생산(GRDP), 고용률(EPR) 데이터를 이용하여 통계적 검정과 패널분석의 이중차분모형(Difference-In-Difference model)으로 살펴보고, 세 변수의 관계를 지역별 데이터 및 패널 벡터오차수정모형(PVECM: Panel Vector Error Correction Model)을 이용하여 살펴보았다. FDI 신고액 대비 도착액의 비율인 실투자율 연평균증가율의 경우 수도권이 비수도권보다 높게 나타났다. FDI 도착액의 성장과 상대적 규모를 살펴보면 16개 지역 중 7개 지역이 성장도 낮고, 규모도 작은 것으로 나타났다. 통계적 분석 결과 지구지정 전후의 변화에서 2개 지역을 제외하고는 일부 변수에서 통계적으로 유의한 차이가 나타났으나 순수한 지구지정 정책효과인 지를 판단할 수 있는 이중차분 추정치는 통계적 유의성이 없는 것으로 나타났다. 한편, PVECM을 이용하여 세 변수의 상호 관계를 분석해 본 결과 상호 설명력은 상당히 제한적이었으나 수도권 지역보다는 비수도권 지역에서, 광역지역 보다는 시도지역에서 크게 나타났다. 이상의 결과를 종합해 볼 때, FDI 유입이 GRDP 증가 및 고용률 상승 등 지역경제 활성화로 연결될 수 있는 FDI 유치 메커니즘을 구축하는 것이 필요하다고 하겠다.

기울기 벡터 계산법이 LMS 알고리즘을 이용한 적응 빔포밍에 미치는 영향

채광철(Kwang-Chol Chae),조기량(Ki-Ryang Cho) 한국전자통신학회 2023 한국전자통신학회 논문지 Vol.18 No.3

본 논문에서는 희망하는 빔포밍을 실현하기 위하여 LMS 알고리즘(반복법)을 이용하는 경우에 반복 계산과정에서 무게 분포를 조절하기 위한 기울기 벡터의 계산법(해석적인 방법, 중앙유한차분법)이 적응 빔포밍에 미치는 영향을 연구하였다. 이를 위하여 임의로 설정한 빔폭을 갖는 준이상 빔과 회전 빔, 그리고 멀티 빔을 예로 하여 검토하였다. 수치 실험은 적응 빔포밍 시스템에 임의의 초기치와 시행착오를 거쳐서 설정한 적절한 값의 스텝 파라미터를 두 계산법에 동일하게 적용하고, 기울기 벡터의 계산을 위한 두 가지 방법을 이용하여 적응성과 오차를 평가하는 목적 함수의 수렴 특성 등을 비교하였다. In this paper, we study the effect of gradient vector calculation method(analytical method, central finite difference method) on adaptive beamforming to control weight distribution during iterated calculation when LMS algorithm (repeating method) is used to realize desired beam pattern. To this end, a quasi-ideal beam having an arbitrarily set beam width, a rotating beam, and a multi-beam were reviewed as examples. Numerical experiments applied the step parameters of the appropriate values to the adaptive beamforming system through trial and error equally to the two calculations, and compared the convergence characteristics of objective functions that evaluate adaptability and error using two methods for calculating gradient vectors.

MPEG-4 Part 10 동영상 압축 표준 성능 개선을 위한 새로운 부호화 방식

문용호,Moon, Yong-Ho 한국통신학회 2006 韓國通信學會論文誌 Vol.31 No.11C

본 논문에서는 MPEG-4 Part 10 동영상 압축 표준에 대한 새로운 움직임 벡터 부호화 알고리듬을 제안한다. 제안 알고리듬에서는 주변 블록들의 움직임 벡터 분포와 MPEG-4 Part 10의 구문 요소인 매크로블록 유형을 이용하여 주어진 동영상의 움직임 정도를 예측한다. 그리고 예측 결과에 따라서 독립 부호화 방식과 결합 부호화 방식을 적응적으로 선택하여 움직임 벡터 압축을 수행한다. 모의 실험 결과는 부가적인 메모리나 계산량 없이 제안 방식이 기존 방식들보다 우수한 압축 성능을 지님을 보여준다. In this paper, we propose a new motion vector coding algorithm suitable for MPEG-4 Part 10 video coding standard. In the proposed algorithm, the amount of the motion for a given video sequence is Predicted by using a characteristic of the motion vector distribution for the neighboring blocks as well as the MB_type, which is the syntax element in the standard. And one of the independent coding and the combined coding methods is adaptively employed to compress the motion vector difference. Simulation results show that the proposed algorithm outperforms the conventional methods without additional memory and calculations.

센서와 영상을 이용한 이상 행동 모니터링 시스템

김상수(Sang-soo Kim),김선우(Sun-woo Kim),최연성(Yeon-sung Choi) Korean Institute of Information Scientists and Eng 2014 정보과학회논문지 Vol.41 No.12

In this paper, we presents a system to ensure the safety of residents through appropriate action or alarm in case the residents occurs an emergency situation and abnormal activity. We collect and analysis real-time data of living environment of the residents using video and sensor. The existing system have been determined by using only the sensor data it have several problems. Our system attach camera to solve the existing system problem. We use weighted difference image and motion vector. The existing system, it takes about 48 hours to determine that an abnormal activity occurs. However, our system takes less than 1 hour.

Phased-in 코드를 이용한 움직임 벡터 예측기의 효율적인 부호화 방법

문지희(Ji-Hee Moon),최정아(Jung-Ah Choi),호요성(Yo-Sung Ho) 한국방송·미디어공학회 2010 방송공학회논문지 Vol.15 No.3

The H.264/AVC video coding standard performs inter prediction using variable block sizes to improve coding efficiency. Since we predict not only the motion of homogeneous regions but also the motion of non-homogeneous regions accurately using variable block sizes, we can reduce residual information effectively. However, each motion vector should be transmitted to the decoder. In low bit rate environments, motion vector information takes approximately 40% of the total bitstream. Thus, motion vector competition was proposed to reduce the amount of motion vector information. Since the size of the motion vector difference is reduced by motion vector competition, it requires only a small number of bits for motion vector information. However, we need to send the corresponding index of the best motion vector predictor for decoding. In this paper, we propose a new codeword table based on the phased-in code to encode the index of motion vector predictor efficiently. Experimental results show that the proposed algorithm reduces the average bit rate by 7.24% for similar PSNR values, and it improves the average image quality by 0.36㏈ at similar bit rates.

A transductive least squares support vector machine with the difference convex algorithm

Jooyong Shim,Kyungha Seok 한국데이터정보과학회 2014 한국데이터정보과학회지 Vol.25 No.2

Unlabeled examples are easier and less expensive to obtain than labeled exam-ples. Semisupervised approaches are used to utilize such exam-ples in an effort to boost the predictive performance. This paper proposes a novel semisupervised classification method named transductive least squares support vector machine (TLS-SVM), which is based on the least squares support vector machine. The proposed method utilizes the difference convex algorithm to derive nonconvex minimization solutions for the TLS-SVM. A generalized cross validation method is also developed to choose the hy-perparameters that affect the performance of the TLS-SVM. The experimental results confirm the successful performance of the proposed TLS-SVM.

A transductive least squares support vector machine with the difference convex algorithm

심주용,석경하 한국데이터정보과학회 2014 한국데이터정보과학회지 Vol.25 No.2

Unlabeled examples are easier and less expensive to obtain than labeled examples. Semisupervised approaches are used to utilize such examples in an effort to boost the predictive performance. This paper proposes a novel semisupervised classification method named transductive least squares support vector machine (TLS-SVM), whichis based on the least squares support vector machine. The proposed method utilizesthe difference convex algorithm to derive nonconvex minimization solutions for the TLS-SVM. A generalized cross validation method is also developed to choose the hyperparameters that affect the performance of the TLS-SVM. The experimental results confirm the successful performance of the proposed TLS-SVM.