• Journal of the Korean Data and Information Science Society
• /
• 제14권3호
• /
• pp.687-696
• /
• 2003

This article presents a new family of the estimating functions related with minimum distance estimations, and discusses its relationship to the family of the minimum density power divergence estimating equations. Two representative minimum distance estimations; the minimum $L_2$ distance estimation and the minimum Hellinger distance estimation are studied in the light of the theory of estimating equations. Despite of the desirable properties of minimum distance estimations, they are not widely used by general researchers, because theories related with them are complex and are hard to be computationally implemented in real problems. Hopefully, this article would be a help for understanding the minimum distance estimations better.

• 한국컴퓨터정보학회논문지
• /
• 제4권1호
• /
• pp.15-20
• /
• 1999

본 논문에서는 CBM(Computer Based Multimedia) 기반의 원격교육을 위해 요구되는 몇 가지 필요사항을 제시한다. CBM 기반의 원격교육은 초고속 통신망을 이용한 가상 공간상에서 실시간 상호작용 응용인 원격 가정학습 시스템을 멀티미디어 기술과 접목한 멀티미디어 원격교육의 한 형태이다. 본 논문에서 제시되는 요구사항들은 멀티미디어 통신을 위한 국제 표준인 ITU (International Telecommunication Union)의 표준화 규격을 따르고 있으며, 제시하는 통합 홈 정보서비스의 구조는 IEEE 1394시리얼 통신과 POF(Plastic Optical Fiber) 가정용 백본을 기반으로 하고 있다.

• Journal of Electrical Engineering and Technology
• /
• 제13권6호
• /
• pp.2196-2202
• /
• 2018

The conventional power system allowed only downstream power flow. Therefore, even if a fault occurs, only the forward current flow is considered. However, with the interest in distributed generation (DG), DGs such as Photovoltaic (PV), Wind Turbine (WT) are being connected to a power system. DGs have many advantages, but they also have disadvantage such as generation of reverse flow. Reverse flow can severely disrupt existing protection systems that only consider downstream power flow. The major problems that may arise from reverse power flow are blinding protection and sympathetic tripping. In order to solve such problems, the methods of installing a directional relay or a fault current limiter is proposed. However, this method is inconceivable because of the economics shortage. Therefore, in this paper, a distance relay installed in existing power system is used to solve the protection problem. Modeling of distance relay has been carried out using ElectroMagnetic Transients Program (EMTP), and it has been verified through simulations that the above problems can be solved by a distance relay.

• BMB Reports
• /
• 제46권6호
• /
• pp.305-309
• /
• 2013

The determination of relatedness between individuals in a family is crucial in analysis of common complex diseases. We present a method to infer close inter-familial relationships based on SNP genotyping data and provide the relationship coefficient of kinship in Korean families. We obtained blood samples from 43 Korean individuals in two families. SNP data was obtained using the Affymetrix Genome-wide Human SNP array 6.0 and the Illumina Human 1M-Duo chip. To measure the kinship coefficient with the SNP genotyping data, we considered all possible pairs of individuals in each family. The genetic distance between two individuals in a pair was determined using the allele sharing distance method. The results show that genetic distance is proportional to the kinship coefficient and that a close degree of kinship can be confirmed with SNP genotyping data. This study represents the first attempt to identify the genetic distance between very closely related individuals.

• 한국항공우주학회지
• /
• 제41권5호
• /
• pp.422-428
• /
• 2013

최근에 소형무인기(small UAV)에 대한 관심이 증대되고 있는데, 이는 소형무인기가 비용대비 효율적이고 사람의 접근이 어려운 재난 환경 등에 적합하기 때문이다. 이러한 소형무인기에서 거리측정을 통한 매핑(mapping)은 필수적인 기술이다. 기존의 무인시스템 연구에서 거리 측정 센서는 주로 레이저 센서와 스테레오 비전 센서를 많이 사용하였다. 레이저 센서는 정확도와 신뢰성이 우수하지만 대부분 고가의 장비이고 스테레오 비전 센서는 구현이 용이하지만 무게 측면에서 소형무인기에 탑재하여 사용하기에는 적합하지 않다. 본 논문에서는 레이저 포인터와 단일 카메라를 사용하여 저가의 거리측정기를 구성하는 방안을 소개한다. 제안한 시스템을 이용하여 거리를 측정하고 이로부터 맵을 구성하는 실험을 수행하였고 실제 데이터와 비교 분석하여 시스템의 신뢰성을 검증하였다.

• 한국정보과학회논문지:소프트웨어및응용
• /
• 제29권9호
• /
• pp.631-644
• /
• 2002

In this paper efficient algorithms for content-based video retrieval using motion information are proposed, including temporal scale-invariant retrieval and temporal scale-absolute retrieval. In temporal scale-invariant video retrieval, the distance transformation is performed on each trail image in database. Then, from a given que교 trail the pixel values along the query trail are added in each distance image to compute the average distance between the trails of query image and database image, since the intensity of each pixel in distance image represents the distance from that pixel to the nearest edge pixel. For temporal scale-absolute retrieval, a new coding scheme referred to as Motion Retrieval Code is proposed. This code is designed to represent object motions in the human visual sense so that the retrieval performance can be improved. The proposed coding scheme can also achieve a fast matching, since the similarity between two motion vectors can be computed by simple bit operations. The efficiencies of the proposed methods are shown by experimental results.

• Asia pacific journal of information systems
• /
• 제12권3호
• /
• pp.45-70
• /
• 2002

This paper examines the role of distance learning self-efficacy, belief in one's capabilities of using a system in the accomplishment of web-based distance learning, in predicting user intention to use and performance of distance learning system. It used self-efficacy theory and technology acceptance model(TAM) to build a model that predicts relationships between antecedents to students' distance learning self-efficacy assessments and their behavioral and attitudinal consequences. The model was tested using LISREL analysis on the sample of 250 students who have worked with the Distance Learning System. The results indicated partial support for the conceptual model. In accordance with TAM, perceived usefulness had strong direct effects on intention to use and performance, while perceived ease of use had both direct and indirect effects on intention to use, but not performance. Distance learning self-efficacy had only direct effect on perceived ease of use to use. Computer experience was found to have a strong positive effect on distance learning self-efficacy, and computer anxiety had a negative effect on distance learning self-efficacy. Implications of these findings are discussed for researchers and practitioners.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2022년도 춘계학술대회
• /
• pp.352-354
• /
• 2022

카메라를 이용한 위치 측정은 오랫동안 많은 연구가 진행되고 있다. 이것은 자율주행 자동차에서 차간거리 인식이나 객체 인식을 위한 연구가 있고, GPS를 적용하기 어려운 한정된 공간인 실내의 내비게이션 분야에서 연구되고 있다. 보통, 카메라를 이용하는 거리를 측정하는 방법은 2개의 스테레오 카메라를 이용하여 카메라 사이의 거리와 촬영된 영상이나 사진을 통해 측정된 값을 이용하여 거리를 측정한다. 본 논문에서는 하나의 카메라를 이용하여 사물의 거리를 측정하는 방법을 제안한다. 제안하는 방법은 촬영 시간의 차이, 촬영 사이의 거리를 통하여 스테레오 카메라와 같이 카메라 간의 거리, 촬영된 사진에 의해 측정된 값을 이용하여 거리를 측정한다.

• Journal of information and communication convergence engineering
• /
• 제10권2호
• /
• pp.181-186
• /
• 2012

Telematics services include automatic location tracking for emergency rescue, which is available for use in case of a car accident due to falling off roadways. This paper presents a simulation study on how far a car will fall before it hits the ground if it drops off of a roadway due to an accident or a natural disaster. The greatest horizontal distance the falling car can travel is presented in this paper, based on the assumption that air resistance as well as the direction and degree of acceleration due to gravity is negligible. This paper also presents the depth of the dent caused by the car sinking into the ground, the time it took for the car to fall free, and the velocity at which it travelled and horizontal distance it traveled. In this paper, the damage done to cars that crash into the ground and the dangers thereof are graphically represented.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (A)
• /
• pp.533-535
• /
• 2003

The Euclidean distance is sensitive to the absolute offsets of time sequences, so it is not a suitable similarity measure in terms of shape. In this paper. we propose an indexing scheme for efficient matching and retrieval of time sequences based on the minimum distance. The minimum distance can give a better estimation of similarity in shape between two time sequences. Our indexing scheme can match time sequences of similar shapes irrespective of their vortical positions and guarantees no false dismissals