• Title/Summary/Keyword: foreign objects

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Comparison of Model Fitting & Least Square Estimator for Detecting Mura (Mura 검출을 위한 Model Fitting 및 Least Square Estimator의 비교)

  • Oh, Chang-Hwan;Joo, Hyo-Nam;Rew, Keun-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.5
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    • pp.415-419
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    • 2008
  • Detecting and correcting defects on LCD glasses early in the manufacturing process becomes important for panel makers to reduce the manufacturing costs and to improve productivity. Many attempts have been made and were successfully applied to detect and identify simple defects such as scratches, dents, and foreign objects on glasses. However, it is still difficult to robustly detect low-contrast defect region, called Mura or blemish area on glasses. Typically, these defect areas are roughly defined as relatively large, several millimeters of diameter, and relatively dark and/or bright region of low Signal-to-Noise Ratio (SNR) against background of low-frequency signal. The aim of this article is to present a robust algorithm to segment these blemish defects. Early 90's, a highly robust estimator, known as the Model-Fitting (MF) estimator was developed by X. Zhuang et. al. and have been successfully used in many computer vision application. Compared to the conventional Least-Square (LS) estimator the MF estimator can successfully estimate model parameters from a dataset of contaminated Gaussian mixture. Such a noise model is defined as a regular white Gaussian noise model with probability $1-\varepsilon$ plus an outlier process with probability $varepsilon$. In the sense of robust estimation, the blemish defect in images can be considered as being a group of outliers in the process of estimating image background model parameters. The algorithm developed in this paper uses a modified MF estimator to robustly estimate the background model and as a by-product to segment the blemish defects, the outliers.

A Study on the Recognition to Secondary School Home Economics Education and Its Necessity Degree in Each Field of Curriculum (중학교 가정과 교육에 대한 인식 및 교과영역별 필요도에 관한 조사연구 -서울시내 중학교 학생과 학부모를 중심으로-)

  • 이은정;신상옥
    • Journal of Korean Home Economics Education Association
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    • v.4 no.1
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    • pp.17-30
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    • 1992
  • This study aims at finding a new home economics education with will include male students as its teaching objects, and then providing home economics teachers with useful materials. For this purpose I examined the curriculum of foreign home economics education and analized male and female secondary school students’and their recognition and demand to the home economics education. Investigated persons are male and female students of the first year of 3 sendary schools and their parents in Seoul, who are choosen by menas of random sampling. The items analysis of questionnaires was performed by means of random sampling. The items analysis of questionnaires was performed by means of SPSS. The results are marked with percentage and the significance level is verified by t and X(sup)2 analysis methods. The results obtained from the items analysis are as follows:1 According to the increasing number of female employees, the mechanization of household affaires, and so on, male students and male parents got to realize the necessity of home economics education and the importance of men and women’s cooperation to lead a family life. 2. It is shown that the goal of home economics deucation must be to form a right value point of the family life and family. This fact implies that many examinees regards the home economics education in the moral point of view. 3. In the necessity degree according to each field of the home economics education curriculum, moral and social aspects such as family relationship, home management & economics, human development and bringing up are regarded more important than household affairs and the related technical aspects. 4. In the difference between groups to the necessity degree according to each field of the home economics education curriculum, there are few differences between male and female parents, but there are many differences between male and female students. Male students regards the contents of the home economics education curriculum less necessary than female students. Especially in the field of clothing, residence, human development and bringing up, the difference between male and female students is obvious. 5. The necessity degree of the contents related to environmental pollution, saving of energy and resources, utilizing of computer, etc. is very high.

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Information Seeking, Evaluation, and Use on the Internet: A Case Study of Science and Engineering Scholars (인터넷의 정보의 탐색, 평가 및 활용:대학 이공계 연구자의 사례를 중심으로)

  • 이해영;이수영
    • Journal of the Korean Society for information Management
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    • v.18 no.4
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    • pp.163-181
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    • 2001
  • The Internet offers a challenging information seeking environment for users due to a great amount of information, heterogeneous objects, and diverse information quality. The purpose of this study was to identify the ways of information seeking, evaluating, and using in the Internet by looking at search behaviors of science and engineering scholars in Korean university. The research problems addressed in the study include the utility of web information, information searching strategies, the extent of search engines usage, and scholarly value of information in the Internet. The data were collected through individual interviews with 28 scholars recruited from science and engineering fields at the Myongji University. It was found that the scholars in this study less likely turn to search engines for finding research information than types of information while they use search engines primarily for searching personal information such as travel and hobbies. This is partly because the scholars believe that the information, especially research-related information, in the Internet lacks the value as scholarly information. They also tend to believe that foreign literature available in the Internet is more credible, professional, and recent than domestic literature. In conclusion, the implications for search engine developers, librarians, and researchers as users and producers in the Internet are discussed.

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The Effective Policy for the Establishment of Disaster Management System in Korea (우리나라의 효과적(效果的)인 재난관리체제(災難管理體制) 구책방안(構策方案)에 관한 연구(硏究))

  • Park, Dong-Kyun
    • Korean Security Journal
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    • no.3
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    • pp.83-116
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    • 2000
  • Many concerns have been raised for importance of disaster management after 1990's numerous urban disasters in Korea. When the primary function of government is to protect lives and property of citizens, disaster management should be included in the mainstream of public administration and many hazard countermeasures should be carried out for that purpose. The principal purpose of this research is to establish ways and means needed to improve the disaster management system in Korea. This paper is split into five chapters. Chapter I is the introduction part. Chapter II introduces the reader to a disaster management theory, and deals with various disaster management systems of foreign countries such as the U.S.A. and Japan, Chapter III describes and characterizes the Korea's current disaster management system. The Korean disaster management system has been reestablished through the enactment of the Disaster Management Act of 1995 and the full revision of Natural Hazards Management Act of 1995 after series of catastrophic man-made disasters since 1993. Chapter IV is devoted to the establishment of an effective disaster management system in Korea. In this chapter, I discusses measures needed to improve the quality of CDMB(Central Disaster Management Bureau)'s service to the people. I strongly reemphasize the effectiveness of a comprehensive risk-based, all-hazard national emergency management system that addresses preparedness, mitigation, response, and recovery. To that end the Administration should develop legislation, new policies, and organizational plans to invigorate the agency with a refocussed mission. Chapter V is a conclusion. As the demand for citizens'welfare has been continuously increased in the localization, the importance of disaster management is emerging subject in the public sector. The disaster management carries out complicated affairs and manages diverse objects, the cooperation/connection system of the central-local government and citizens, and non-governmental organization should be established.

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Study of consciousness about employment overseas of dental hygiene students abroad (치위생과 학생들의 해외취업에 관한 의식)

  • Kim, Hwa-Ju;Lim, Kun-Ok;Jung, Sang-Hee
    • Journal of Korean society of Dental Hygiene
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    • v.6 no.3
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    • pp.175-185
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    • 2006
  • This study got a conclusion following by questionnaire individual own recording law from Mokpo, Iksan, Gangneung to the objects to the academic 608 Dental Hygiene students whom had for consciousness investigations about employment overseas of some special college Dental Hygiene students. 1. Regarding the motivating factors to major in Dental Hygiene, most students(51.3%), particularly most freshmen(57.3%), have chosen this major because of more job opportunities than students with other majors. The most common source of information in choosing majors is the Internet(30.8%). 2. Many students have heard about overseas employment, particularly in case of juniors(82.5%). They want to work abroad if they are given the chances(70.6%), which indicates that the Dental Hygiene majors have much interest and positive attitude in overseas employment. 3. The most significant barrier to their overseas employment is the language, and thus the Dental Hygiene majors should improve their language abilities to be more involved in working abroad. 4. Showed the difference that an experience and light oil, the country where wanted to get a job at that tried to listen to relevance about employment of dental hygiene students by a school year abroad about these results, overseas employment noted. 5. While 'foreign language education must become activation' showed average highest, results to have seen relevance about employment time promotion plan overseas of dental hygiene students by a school year showed a difference by a school year.

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A study of improvement on safety regulation for slip, trip and fall prevention (넘어짐(전도) 재해예방 안전기준 개정(안) 연구)

  • Kim, Jeong-Su
    • Proceedings of the Safety Management and Science Conference
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    • 2013.04a
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    • pp.19-29
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    • 2013
  • Slips and falls are associated with many occupational injuries in Korea. It is also estimated that slipping are major contributors to slip, trip and fall injury burden. So "LOCAL RULE ON OCCUPATIONAL SAFETY AND HEALTH STANDAR D" must be improved, especially article 3(prevention of slip, trip and fall). The primary purpose of the present study is to determine if, and to what extent, the standard could be improved in present environment. In order to fulfill our objective, the another regulation in Korea and foreign countries were investigated and reviewed. Many kind of standard, mandatory documents and guideline were also reviewed. And then, regulations, standard, guideline etc. reviewed were compared with each others. The article 3 was revised as below. 1. The floors of the traffic route in workplace shall have no hole or slope, or be uneven or slippery so as, in each case, to expose employees to slip, trip and fall risk, except if adequate measures have been taken to prevent a employees falling. 2. The employer shall design, install and fix the drain for effective drainage if fluid contaminants were frequently occurred. So far as is reasonably practicable, An employer shall keep the workplace clean, sanitary, and dry so that employees won't have any risk to tripping or slipping at the workplace. 3. To facilitate cleaning, every floor, workplace, and passageway shall be, so far as is reasonably practicable, kept free from protruding objects, splinters, holes, etc. Also, some criteria was developed in this study. Standard and criteria developed in this study will help to prevent slip, trip, and fall injuries.

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Implementation of Autonomous Mobile Wheeled Robot for Path Correction through Deep Learning Object Recognition (딥러닝 객체인식을 통한 경로보정 자율 주행 로봇의 구현)

  • Lee, Hyeong-il;Kim, Jin-myeong;Lee, Jai-weun
    • The Journal of the Korea Contents Association
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    • v.19 no.12
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    • pp.164-172
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    • 2019
  • In this paper, we implement a wheeled mobile robot that accurately and autonomously finds the optimal route from the starting point to the destination point based on computer vision in a complex indoor environment. We get a number of waypoints from the starting point to get the best route to the target through deep reinforcement learning. However, in the case of autonomous driving, the majority of cases do not reach their destination accurately due to external factors such as surface curvature and foreign objects. Therefore, we propose an algorithm to deepen the waypoints and destinations included in the planned route and then correct the route through the waypoint recognition while driving to reach the planned destination. We built an autonomous wheeled mobile robot controlled by Arduino and equipped with Raspberry Pi and Pycamera and tested the planned route in the indoor environment using the proposed algorithm through real-time linkage with the server in the OSX environment.

Outlier-Object Detection Using an Image Pair Based on Regression Analysis: Noise Variance Estimation and Performance Analysis (영상 쌍에서 회귀분석에 기초한 이상 물체 검출: 잡음분산의 추정과 성능 분석)

  • Kim, Dong-Sik
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.5
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    • pp.25-34
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    • 2008
  • By comparing two images, which are captured with the same scene at different time, we can detect a set of outliers, such as occluding objects due to moving vehicles. To reduce the influence from the different intensity properties of the images, an intensity compensation scheme, which is based on the polynomial regression model, is employed. For an accurate detection of outliers alleviating the influence from a set of outliers, a simple technique that reruns the regression is employed. In this paper, an algorithm that iteratively reruns the regression is theoretically analyzed by observing the convergence property of the estimates of the noise variance. Using a correction constant for the estimate of the noise variance is proposed. The correction enables the detection algorithm robust to the choice of thresholds for selecting outliers. Numerical analysis using both synthetic and Teal images are also shown in this paper to show the robust performance of the detection algorithm.

Policy Tasks in the Enforcement of the Police Order With Regard to Electronic Security (기계경비업무 감독명령 시행의 정책과제)

  • Ha, Kyungsu;Lee, Sangchul
    • Journal of the Society of Disaster Information
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    • v.10 no.2
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    • pp.200-207
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    • 2014
  • In this research, The Police Order No. 2013-1, which is 'Electronic Security 112 Report Standards,' was analyzed and the relevant policy tasks were presented. The policy tasks to achieve the purpose of the selective report system are as follows. First, in order to construct the statistics base, the establishment of the terms related to false alarm and false call, emergency button, and sensing signal and the development of the appropriate term to replace the electronic security guard are needed. Second, the electronic security companies should build the response system to abide by the 112 report standards of the police order. Third, the police should reexamine the establishment of the emergency report objects of the selective report system. Fourth, the reinforcement of the administrative regulation and supervision to enforce the police order strictly is required.

In-Situ Application Study on the Power Plant Valve Leak Diagnosis Using Acoustic Emission Technology (음향방출을 이용한 발전용 밸브 누설 진단 현장 적용 연구)

  • Lee, Sang-Guk
    • Journal of the Korean Society for Nondestructive Testing
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    • v.28 no.4
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    • pp.315-322
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    • 2008
  • Valves in power plants are leaking internally by various damages including insertion of foreign objects on seat, seat crack, defects and fatigue crack of stem packing or welds etc. due to severe operating conditions such as high temperature and high pressure for extended period time. Acoustic emission(AE) technology should be applied in order to diagnose precisely and evaluate these valve internal leak. In this paper, results of studies which have accomplished in actual power plant are presented. We have analyzed background noise, AE signal level and frequency spectrum through laboratory tests on the basis of various actual conditions in power plant, and also have considered evaluation methods on the background noise, AE properties and the detectable minimum leak rate according to valve leak conditions through comparing with results of field tests in power plant. As a result of these studies, we conformed that evaluation of internal leak conditions including discrimination of leak or not, and the detectable minimum leak rate is possible, and also it is expected to contribute to safe operation and prevention of energy loss in power plants.