• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권5호
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• pp.2142-2161
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• 2018

Distance dynamics model is an excellent model for uncovering the community structure of a complex network. However, the model has poor robustness. To improve the robustness, we design an enhanced distance dynamics model based on Ego-Leader and propose a corresponding community detection algorithm, called E-Attractor. The main contributions of E-Attractor are as follows. First, to get rid of sensitive parameter ${\lambda}$, Ego-Leader is introduced into the distance dynamics model to determine the influence of an exclusive neighbor on the distance. Second, based on top-k Ego-Leader, we design an enhanced distance dynamics model. In contrast to the traditional model, enhanced model has better robustness for all networks. Extensive experiments show that E-Attractor has good performance relative to several state-of-the-art algorithms.

• International Journal of Computer Science & Network Security
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• 제21권5호
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• pp.69-72
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• 2021

The article discusses the features of the use of distance technologies to intensify the learning process of students. The advantages and disadvantages of distance learning are shown. The role and functions of the teacher in distance learning have been adjusted. Information and methodological support for distance learning of students is proposed. Analyzed pedagogical, psychological, methodological and philosophical literature, educational standards, charters of higher educational institutions and other documents. Studied foreign experience in conducting classes using information technology.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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• pp.500-503
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• 2003

The navigation problem of robot is one of the main themes to deal with conficts or interferences between obstacles and the robot itself In this case, while the robot avoids obstacles on the space, the passage route should be determined efficiently. In order to solve problems above, we have come up with the distance field space medel (DFM) and then, under known environment, we have presented the distance field A algorithm for passage route path search. In this research, the method of performing the 3-dimensional passage route path search of robot under unknown environment is proposed. It is shown that the authors can build the distance search model the does not need space division by taking into account of sensor information to a distance field space model, and constructing this information as virtual obstacle information.

• 대한전기학회논문지:전력기술부문A
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• 제52권3호
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• pp.183-192
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• 2003

This paper presents the real-time implemented distance relay algorithm which the fault distance is estimated with only local terminal information. When a single-phase-to-earth fault on a two-parallel transmission line occurs, the reach accuracy of distance relay is considerably affected by the unknown variables which are fault resistance, fault current at the fault point and zero- sequence current of sound line The zero-sequence current of sound line is estimated by using the zero sequence voltage which is measured by relaying location Also. the fault resistance is removed at the Process of numerical formula expansion. Lastly, the fault current through a fault point is expressed as a function of the zero-sequence current of fault line, zero-sequence current of sound line, and line, and fault distance. Therefore, the fault phase voltage can be expressed as the quadratic equation of the fault distance. The solution of this Quadratic equation is obtained by using a coefficient of the modified quadratic equation instead of using the square root solution method. After tile accurate fault distance is estimated. the mote accurate impedance is measured by using such an information.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(4)
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• pp.85-87
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• 2000

In pattern classification, the Bhattacharyya distance has been used as a class separability measure and provides useful information for feature selection and extraction. In this paper, we propose a method to predict the classification error for multimodal data based on the Bhattacharyya distance. In our approach, we first approximate the pdf of multimodal distribution with a Gaussian mixture model and find the bhattacharyya distance and classification error. Exprimental results showed that there is a strong relationship between the Bhattacharyya distance and the classification error for multimodal data.

• 한국광학회지
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• 제17권6호
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• pp.537-543
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• 2006

단일 줌 카메라를 사용한 거리추정 방법은 시야 범위가 광 축으로 제한되기 때문에 거리 추정에는 한계가 있다. 본 논문에서는 넓은 범위에서 거리추정을 위한 수평이동 방식의 줌 렌즈를 이용한 입체영상에서의 물체의 거리 추정 방법을 제안한다. 거리 추정을 위하여 줌렌즈를 이용한 수평이동방식 카메라를 구현하였다. 제안한 방법으로 또한 편광 입체영상 모니터를 사용하여 카메라의 좌, 우 영상 정보를 획득하였다. 인간이 볼 수 있는 시야 범위를 추정하기 위해 좌, 우로 $0mm{\sim}500mm$ 범위에서 실 거리와 추정 거리를 구하였고 이의 오차는 10mm 미만이었다. 입체 카메라의 주시각 제어에 줌 기능을 사용하여 제어의 오차를 줄였기 때문에 주시각에 의한 거리 추정에서 보다 더욱 정확한 거리를 추정 할 수 있었다. 또한 교차방식과 수평이동방식의 거리 추정의 오차를 비교하여 수평이동 방식이 교차방식보다 더욱 정확한 거리 정보를 추정을 확인하였다.

• Communications for Statistical Applications and Methods
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• 제24권3호
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• pp.317-324
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• 2017

An influence measure known as Cook's distance has been used for judging the influence of each observation on the least squares estimate of the parameter vector. The distance does not reflect the distributional property of the change in the least squares estimator of the regression coefficients due to case deletions: the distribution has a covariance matrix of rank one and thus it has a support set determined by a line in the multidimensional Euclidean space. As a result, the use of Cook's distance may fail to correctly provide information about influential observations, and we study some reasons for the failure. Three illustrative examples will be provided, in which the use of Cook's distance fails to give the right information about influential observations or it provides the right information about the most influential observation. We will seek some reasons for the wrong or right provision of information.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1679-1684
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• 2004

This paper introduces a novel approach that can provide the three dimensional information on the movement of a spreader by using two CCD cameras and a laser distance sensor, which enables an ALS (Automatic Landing System) to be used for yard cranes at a harbor. So far a kind of 2D Laser scanner sensor or laser distance measuring units are used as corner detectors for the geometrical matching between the spreader and a container, which provides only 2D information which is not enough for an accurate and fast ALS system required presently. In addition to this deficiency in performance, the price for the system is too high to be adopted widely for the ALS. Therefore, to overcome these defects, a novel method to acquire the three dimensional information for the movement of a spreader including skew and sway angles is proposed using two CCD cameras and a laser distance sensor. To show the efficiency of proposed algorithm, real experiments are performed to show the accuracy improvement in distance measurement by fusing the sensory information of CCD camera and laser distance sensor.

• 한국항해항만학회지
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• 제28권4호
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• pp.323-331
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• 2004

This paper introduces a novel approach that can provide the three dimensional information about the movement of a spreader by using two CCD cameras and a laser distance measuring unit in order to derive ALS (Automatic Landing System) in the crane used at a harbor. So far a kind of 2D Laser scanner sensor or laser distance measuring units are used as comer detectors for the geometrical matching between the spreader and a container. Such systems provide only two dimensional information which is not enough for an accurate and fast ALS. In addition to this deficiency in performance, the price of the system is too high to adapt to the ALS. Therefore, to overcome these defects, we proposed a novel method to acquire the three dimensional spreader information using two CCD cameras and a laser distance measuring unit. To show the efficiency of proposed method, real experiments are performed to show the improvement of accuracy in distance measurement by fusing the sensory information of the CCD cameras and a laser distance measuring unit.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제5권4호
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• pp.316-321
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• 2005

We designed and implemented fish robots for various purposes such as autonomous navigation, maneuverability control, posture balancing and improvement of quick turns in a tank of 120 X 120 X 180cm size. Typically, fish robots have 30-50 X 15-25 X 10-20cm dimensions; length, width and height, respectively. It is essential to have the ability of quick and smooth turning to avoid collision with obstacles or walls of the water pool at a close distance. Infrared distance sensors are used to detect obstacles, magneto-resistive sensors are used to read direction information, and a two-axis accelerometer is mounted to compensate output of direction sensors. Because of the swing action of its head due to the tail fin movement, the outputs of an infrared distance sensor contain a huge amount of noise around true distances. With the information from accelerometers and e-compass, much improved distance data can be obtained by fuzzy logic based estimation. Successful swimming and smooth turns without collision demonstrated the effectiveness of the distance estimation.