• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.5
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• pp.137-147
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• 2006

This is an experimental study on the properties and the strength development of concrete using of the oyster shells as a substitute fine aggregate of concrete. For this purpose, the fundamental experiments of the materials and the main factors on it were considered and then the workability and many kinds of strength about the specimens were also studied. As the experimental results, there were strength differences of less than 10% between concrete with oyster shells and normal and the most excellent grain size of oyster shells is 5.0mm and less with taking uniformly and the percentage of practicable substitution of them to fine aggregate about 30%. This paper also represents the relationship equations among many kinds of strength and elastic modulus of concrete with the oyster shells decreased with increase in proportion of oyster shells and curve of it is similar about the percentage of substitution of 10%.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.12
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• pp.1397-1404
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• 2003

2002년 월드컵 전야제에서는 한국문화를 소개해 세계인의 환호를 받았는데 그 중에는 칠석동 민속축제인 고싸움놀이가 펼쳐졌다. 칠석동 민속축제는 일반 서민복식의 전통복 형태를 보여주는 복식(服飾)을 실제 착용하고 축제를 행하고 있으므로, 점차 사라져 가는 전통복식을 놀이문화를 통해 직접 확인할 수 있다는 점에서 연구가치를 갖는다. 본 연구의 목적은 국제화 시대에 우리 전통문화에 대한 정체성 확립을 위해 시대적 변화에 따라 변해 가는 민속복식을 무형문화재로 지정되어 있는 칠석동 고싸움놀이를 중심으로 시대적 흐름을 통한 고싸움놀이의 전수과정에서 형성되어 온 민속축제복식의 구성과 특성을 살펴보는데 있다. 연구방법은 광주지역인 광산구 칠석동 마을을 중심으로 자료조사와 현장조사를 병행하였다. 자료조사는 민속에 관련된 전공서적과 무형문화재 조사보고서, 행사팜플렛 등을 참고하였고, 현장조사는 고싸움 축제에 참가하여 복식 전반에 대한사진촬영과 마을축제 참여하는 마을사람들을 중심으로 축제복식에 관한 면담조사를 하였다. 칠석동 고싸움 축제복식은 행사가 진행되는 내용에 따라 크게 4가지로 분류할 수 있는데 본격적인 고싸움이 시작되기 전날 밤에 당산나무에 제를 지내는 당산제 복식, 마을의 평안과 고싸움의 흥을 돋우기 위한 농악복식, 고싸움이 시작되기 전에 아낙네들이 손과 손을 맞잡고 둥글게 돌며 화합을 다짐하는 강강수월래 복식, 한해 풍년을 기원하는 고싸움복식이 있다. 칠석동 고싸움 축제복식의 특성을 요약하면 다음과 같다. 첫째, 구성면에서는 농경제의(農耕祭衣)와 안택축원(安宅祝願的)을 기원하는 민속놀이축제복식으로 일상생활에 착용하는 복식을 이용한 농경 의례복의 다(多)기능성이 강조된 것으로 나타났다. 둘째, 색상은 우리조상의 백의(白衣)의 상징인 일상복인 백색 위에 오방색을 사용하여 화려하고도 강렬한 원색의 색상조화가 특징적으로 나타났다. 셋째, 형태면에서는 양쪽어깨와 허리선의 면 분할이나 비례를 통해 허리부분의 동작에 따른 유동적인 선이 부각되고 있다. 특히, 평면구성의 단조로움은 흔들리는 몸동작에 따른 고름의 율동미와 축제복식의 착장 방법에 따른 한국복식의 형태미를 보여주었다.

• Journal of the Korean Magnetics Society
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• v.2 no.3
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• pp.244-250
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• 1992

Iron nitride $Fe_4N$ by partial substitution of nitrogen by carbon was prepared by nitriding the iron oxalate whose thermal decomposition gives a carburating atmosphere. Iron oxalates, the precursors, were prepared by precipitation and co-precipitation. The size and shape of the carbonitride particles could be controlled by modifying the conditions of preparation of the oxalate precursor. From the results of electron micrographs, it is clear that the $Fe_4N$ pigment particle maintains the original shape(needle shape) of the starting materials and that it consists of fine unit particles which link together to form a stereo-network structure. An investigation of the $Fe^{II}_3\;Fe^I_{1-x}\;Sn_xN_{1-y}C_y$ solid solution has shown that Sn plays the role of a growth inhibitor of the elementary microcrystallites of the iron carbonitride. The coercive force and saturation magnetization of iron carbonitride obtained from co-precipitated iron oxalate were 500 Oe and 120 emu/g, respectively.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.5
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• pp.163-168
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• 2009

Most image segmentation methods are to represent observed feature vectors at each pixel, which are assumed as appropriated probability models. These models can be used by statistical estimating or likelihood clustering algorithms of feature vectors. EM algorithms have some calculation problems of maximum likelihood for unknown parameters from incomplete data and maximum value in post probability distribution. First, the performance is dependent upon starting positions and likelihood functions are converged on local maximum values. To solve these problems, we mixed the Gausian function and histogram at all the level values at the image, which are proposed most suitable image segmentation methods. This proposed algoritms are confirmed to classify most edges clearly and variously, which are implemented to MFC programs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11C
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• pp.702-711
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• 2011

In this paper, we derived a closed-form equation of a Best Linear Unbiased Estimator (BLUE) and its Crammer-Rao Lower Bound (CRLB) for the estimation of the position of the emitter based on the Time Difference of Arrival (TDOA) teclmique. The BLUE and CRLB were derived for the case of estimating 2 dimensional position of the emitter with 3 base stations or sensors, and for this purpose, we nsed an approximated equation of the TDOA hyperbola equation obtained from the first order Taylor-series after setting the reference points of the position. The derived equation can be used for any kind of noises which are uncorrelated in each other in the TOA measurement noises and for a white Gaussian noise also.

• Journal of the Korean Data and Information Science Society
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• v.25 no.1
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• pp.1-10
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• 2014

In this paper, we study approximations of the ruin probability in a continuous time surplus process. First, we introduce the well-known approximation formulas of the ruin probability such as Cram$\acute{e}$r, Tijms' and De Vylder's methods. We, then, suggest new approximation formulas of two types, which improve the existing approximation formulas. One is Cram$\acute{e}$r and Tijms' type which makes use of the moment generating function of distribution of a claim size and the other is De Vylder's type which makes use of the surplus process with exponential claims. Finally, we compare, by illustrating numerical examples, the newly suggested approximation formulas with the existing approximation formulas of the ruin probability.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.1
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• pp.27-33
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• 2020

Recently, visual object detection and tracking has become a vital role in many different applications. It spans various applications like robotics, video surveillance, and intelligent vehicle navigation. Especially, in current situation where the use of UAVs is expanding widely, detection and tracking to soot down illegal UAVs flying over the sky at airports, nuclear power plants and core facilities is becoming a very important task. The remarkable method in object tracking is correlation filter based tracker like KCF (Kernelized Correlation Filter). But it has problems related to target drift in tracking process for long-term tracking. To mitigate the target drift problem in video surveillance application, we propose a tracking method which uses KCF, adaptive thresholding and Kalman filter. In the experiment, the proposed method was verified by using monochrome video sequences which were obtained in the operational environment of UAV.

• The Korean Journal of Applied Statistics
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• v.29 no.7
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• pp.1165-1172
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• 2016

In this paper, a surplus process with investments is introduced. Whenever the level of the surplus reaches a target value V > 0, amount S($0{\leq}S{\leq}V$) is invested into other business. After assigning three costs to the surplus process, a reward per unit amount of the investment, a penalty of the surplus being empty and the keeping (opportunity) cost per unit amount of the surplus per unit time, we obtain the long-run average cost per unit time to manage the surplus. We prove that there exists a unique value of S minimizing the long-run average cost per unit time for a given value of V, and also that there exists a unique value of V minimizing the long-run average cost per unit time for a given value of S. These two facts show that an optimal investment policy of the surplus exists when we manage the surplus in the long-run.

• Korean Journal of Animal Reproduction
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• v.11 no.1
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• pp.63-72
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• 1987

Effects of sperm and seminal plasma isoant ibodies upon the rate of superovulation and ferlil ization were slud ied in both normal and immunized rabbits. The results obstained were summarized as follows: 1. On examin.ltion of the superovulation in the immunized animals, the average number of ovulation points was 22.1 and 25.3 for spermtreated animals and for seminal plasma-treated animals, respec tively. As compared to the con¬trol group of 41.0 in number, the immunized showed statisfical significance in ovulation (P<0.05). 2. In ovary weight and follicle's size there were no significant differences among the three groups, whereas sperm-and seminal plasma¬treated groups had an average rate of fertiliza¬tion of 62.X% and 5X .0%, respectively, in re¬markable contrast to the control hTfOUP of 91.4'1'0 (P<0.05). 3. When the animals were inseminated with a mixture of semen plus sperm or seminal plasma antisera, a sharp reduction of fertilization was observed with 5.6% and 16.0% as compared to the control group (P<0.05). Consequently, immunization with either sperm or seminal plasma had a substantial effect on fertilization.

• Journal of Engineering Education Research
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• v.9 no.4
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• pp.10-18
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• 2006

Today it is critical for all engineers to have the capability of interacting in teams with members of different background and to meet the challenges that they will encounters in their careers. To satisfy such needs multidisciplinary engineering-design courses are attracting more attentions than ever in the engineering education community. In this paper we analyze the learning effectiveness of interdisciplinary design teams in an engineering design course in Dongguk University. The comparison analysis between monodisciplinary teams and interdisciplinary ones demonstrates higher learning effectiveness of interdisciplinary teams. In addition, the student evaluation of learning effectiveness points out that communication skill is one of the most important factors for a successful project. Such results show that multidisciplinary design courses must gain wider acceptance in engineering education and engineering students must have more chances to experience multidisciplinary teamwork.