• Journal of Information Processing Systems
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• 제16권2호
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• pp.406-420
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• 2020

In order to make up the deficiencies of the existing research results which cannot effectively deal with the nearest neighbor query based on the line segments in obstacle space, the k nearest neighbor query method of line segment in obstacle space is proposed and the STA_OLkNN algorithm under the circumstance of static obstacle data set is put forward. The query process is divided into two stages, including the filtering process and refining process. In the filtration process, according to the properties of the line segment Voronoi diagram, the corresponding pruning rules are proposed and the filtering algorithm is presented. In the refining process, according to the relationship of the position between the line segments, the corresponding distance expression method is put forward and the final result is obtained by comparing the distance. Theoretical research and experimental results show that the proposed algorithm can effectively deal with the problem of k nearest neighbor query of the line segment in the obstacle environment.

• 한국정보처리학회논문지
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• 제6권8호
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• pp.2213-2221
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• 1999

직선 선분은 선분의 중점에 대하여 대칭 성질을 갖고 있다. 우리는 이 대칭성에 착안하여 직선 생성을 위한 픽셀 선택시 한 번에 두 개의 픽셀을 동시에 선택할 수 있는 수정 브레제남 알고리즘을 제안하였다. 본 알고리즘은 한번에 두 개의 픽셀 위치를 결정하며, 픽셀 별로 각각의 결정 파라미터(decision parameter)를 사용하는 것이 아니라 오직 한 개의 결정 파라미터만을 사용한다. 이러한 선택 방법을 뒷받침하기 위한 이론적 증명을 아울러 제시하였다. 본 논문에서 제안한 알고리즘은 픽셀 선택을 위한 루프 수행 회수가 줄어들기 때문에 직선 생성에 걸리는 시간을 약 5% 내외로 단축할 수 있음을 실험을 통하여 알 수 있었다. 또한, 생성된 직선의 모양은 기존 브레제남 알고리즘의 그것과 일치함을 확인할 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.141-143
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• 2004

This paper represents 3D line segment extraction method, which can be used in generating 3D rooftop model. The core of our method is that 3D line segment is extracted by using line fitting of elevation data on 2D line coordinates of ortho-image. In order to use elevations in line fitting, the elevations should be reliable. To measure the reliability of elevation, in this paper, we employed the concept of self-consistency. We carry out the experiment of 3D line extraction using synthetic images generated from Avenches data set of Ascona aerial images.

• 한국멀티미디어학회논문지
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• 제11권3호
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• pp.292-300
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• 2008

본 논문에서는 점진적인 화소 확장을 이용하여 영상 내에 존재하는 선분을 찾아내는 선분 추출 알고리즘을 제안한다. 본 논문에서 제안하는 선분 추출 방법에서는 기존의 선분 추출 방법인 허프 변환 기반 방법이나 선분의 그룹화 기반 방법과는 다른 접근법을 사용하였다. 영상이 입력되면 케니 테두리를 구하고, 테두리 화소 중 임의의 점을 선택하여 선분을 근사화 시킨 기본 직선을 만든 후, 선택된 점에서 임의의 반경 내에 있는 테두리 화소들을 선택한다. 직선과의 거리 오차와 기울기 각의 오차를 이용하여 선택된 화소에 가중치를 부여한다. 가중치 합 비교에 의해 선택된 화소들이 떨어져 있는지를 판별한 후, 가중치를 적용한 최소자승법에 의해 선 맞춤을 하여 선분을 구하게 된다. 제안된 알고리즘은 기존에 제안된 방법들과 결과를 비교하였으며, 계산 속도가 빠르면서 실제 존재하는 선분 추출이 가능하다는 것을 실험 결과를 통해 제시한다.

• 한국의류학회지
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• 제17권4호
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• pp.608-621
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• 1993

The Purposes of this study were 1)to find the body surface total line and segment line significantly(${\alpha}$=0.05) changed by the leg movement including all movement direction of hip joint, knee joint and ankle joint for the more functional clothing. 2)to classify them into 3 types-expansion type, contraction type, expansion & contraction type, and 3)to identify the characteristics of the body surface length changes. 10 Crosswise and 5 lengthwise body surface total lines and 48 crosswise & 39 lengthwise body surface segment lines of 26 female college students aged from 18 to 24 years were measured directly on the body surface and were analyzed by ANOVA & Multiple Comparison Test (Tukey). The results were as following : Body surface total lines significantly changed were all the body surface total lines except abdoman girth, 1/2thigh girth of lower leg and ankle girth, and these were classified into 3 types : Center front leg line belonged to expansion & contraction type, whereas lateral leg line, legscye girth, and total crotch length belonged to contraction type. The rest belonged to expansion type. Knee girth showed maximum expansion, whereas center front leg line showed maximum contraction. Body surface total lines have shown large expansion crosswise whereas lengthwise they have mainly shown contraction. At least more than one component segment line of each body surface total lines except abdoman girth and ankle girth have shown significant change. Top segment of inner leg line showed maximum expansion. whereas just below top segment of center front leg line showed maximum contraction. Crosswise all the body surface segment lines have shown expansion except inner back segments of thigh girth and 1/2thigh girth of upper leg which have shown contraction. Lengthwise they have shown both expansion and contraction according to the location of front or back, and below or upper 1/2thigh girth line except the component segment lines of lateral leg line, which has shown contraction only.(cf. figure 2. figure 3. and table 2-2).

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.177-181
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• 1999

This paper presents an algorithm for building detection from aerial image using segment measure function and line relation. In the detection algorithm proposed, edge detection, linear approximation and line linking are used and then line measure function is applied to each line segment in order to improve the accuracy of linear approximation. Parallelisms, orthogonalities are applied to the extracted liner segments to extract building. The algorithm was applied to aerial image and the buildings were accurately detected.

• International Journal of Advanced Culture Technology
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• 제6권4호
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• pp.317-322
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• 2018

We use edge detection technique for the input image to extract the entire edges of the object in the image and then select only the edges that construct the outline of the object. By examining the positional relation between these pixels composing the outline, a simplified version of the outline of the object in the input image is generated by removing unnecessary pixels while maintaining the condition of connection of the outline. For each pixel constituting the outline, its direction is calculated by examining the positional relation with the next pixel. Then, we group the consecutive pixels with same direction into one and then change them to a line segment instead of a point. Among those line segments composing the outline of the object, a line segment whose length is smaller than a predefined minimum length of acceptable line segment is removed by merging it into one of the adjacent line segments. As a result, an outline composed of line segments of over a certain length is obtained through this process.

• 복식
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• 제58권2호
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• pp.162-180
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• 2008

The purpose of this study is to find the basic design factors that affect the changes in body surface lines caused by lower limb movements, thereby resulting in slacks that fit well regardless of whether the human form is static or in motion. Using unmarried female university students aged 18-24 as subjects, a total of 32 body surface lines (15 body surface total lines and 17 body surface segment lines) were measured in one static and 9 movement poses, The analysis first involved the calculation of the expansion and contraction rates per body part in body surface line in 9 lower limb movements, Second, a factor analysis was conducted using the expansion and contraction rates of these changes in body surface line. The results of this study are as follows, According to the factor analysis, basic design factors that affect changes in body surface lines comprised 8 types of factors as illustrated in fig, 2-fig, 9, which explained 79.2% of total variate for the variables studied, Factor 1, comprising the lower segment of center back leg line, center front leg line and inner leg line, and lower limb girth except midway thigh girth and ankle girth below hip girth, accounted for 30.3% of total variance, Factor 2, comprising waist girth, the total and upper segment of center back leg line and center tront leg line, and front and back segment of crotch length, explained 17.4% of total variance, Factor 3, the total and upper segment of lateral leg line at the center, accounted for 56.5% of total variance in accordance with Factors 1, 2, and 3, Factor 4 was the contracting upper part of lower leg between legscye girth and midway thigh girth, Factor 5 comprised the total and upper segment of inner leg line and posterior knee girth, Factor 6 was the total crotch length, Factor 7 was the ankle girth, Factor 8 was the abdomen girth.

• 한국철도학회논문집
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• 제16권2호
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• pp.117-121
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• 2013

철도선로구간의 노후도는 궤도, 노반, 교량, 터널 등 요소시설의 노후도로 결정되며 궤도의 선형 또한 선로구간 노후도에 영향을 준다. 본 논문에서는 계층구조분석(analytic hierarchy process: AHP)과 자료포락분석(data envelopment analysis: DEA)을 활용하여 선로구간의 노후도를 평가하는 방법을 제시한다. AHP는 다수의 전문가들이 평가하는 각 요소시설의 중요도를 체계적으로 파악할 수 있도록 해준다. 요소시설에 대한 중요도는 전문가에 따라 달라질 수 있다. DEA는 선로구간 요소시설의 중요도 가중치 범위를 체계적으로 반영하여 선로구간의 노후도를 평가할 수 있도록 해준다.

• 지구물리와물리탐사
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• 제25권1호
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• pp.44-49
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• 2022

이 논문에서는 선형 이상체에 대한 벡터 중력과 중력 변화율 텐서 반응식을 유도하였다. 축대칭성을 가지는 이상체를 멀리서 관측하면 선형 이상체로 근사가 가능하므로 선형 이상체에 대한 중력 및 중력 변화율 해석해가 필요하다. 선형 이상체에 대한 중력 퍼텐셜을 1차원 적분식으로 정의하고 이를 직교 좌표계에서 미분하여 벡터 중력을 유도한다. 중력 변화율 텐서 반응식은 벡터 중력을 직교 좌표계에서 한번 더 미분하여 유도한다.