• Title/Summary/Keyword: Depth-of focus

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A Study on Iris Image Restoration Based on Focus Value of Iris Image (홍채 영상 초점 값에 기반한 홍채 영상 복원 연구)

  • Kang Byung-Jun;Park Kang-Ryoung
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.43 no.2 s.308
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    • pp.30-39
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    • 2006
  • Iris recognition is that identifies a user based on the unique iris texture patterns which has the functionalities of dilating or contracting pupil region. Iris recognition systems extract the iris pattern in iris image captured by iris recognition camera. Therefore performance of iris recognition is affected by the quality of iris image which includes iris pattern. If iris image is blurred, iris pattern is transformed. It causes FRR(False Rejection Error) to be increased. Optical defocusing is the main factor to make blurred iris images. In conventional iris recognition camera, they use two kinds of focusing methods such as lilted and auto-focusing method. In case of fixed focusing method, the users should repeatedly align their eyes in DOF(Depth of Field), while the iris recognition system acquires good focused is image. Therefore it can give much inconvenience to the users. In case of auto-focusing method, the iris recognition camera moves focus lens with auto-focusing algorithm for capturing the best focused image. However, that needs additional H/W equipment such as distance measuring sensor between users and camera lens, and motor to move focus lens. Therefore the size and cost of iris recognition camera are increased and this kind of camera cannot be used for small sized mobile device. To overcome those problems, we propose method to increase DOF by iris image restoration algorithm based on focus value of iris image. When we tested our proposed algorithm with BM-ET100 made by Panasonic, we could increase operation range from 48-53cm to 46-56cm.

Health Status and Health Care System of Homeless Shelter Residents (쉼터거주자의 건강관리실태 및 대안)

  • Han, Young Ran;Yoon, Hee Sang
    • Journal of Korean Public Health Nursing
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    • v.28 no.3
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    • pp.536-552
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    • 2014
  • Purpose: The purpose of this study was to explore how homeless shelter worker and public health nurses perceive health status and health care of homeless shelter residents (HSRs). Methods: Data collected through focus group interviews. In Focus group, in-depth discussions were between 150 to 160 minutes. Data analyzed using Krueger (1998) step analysis. Participants were seven experienced clinical social workers, nurses working homeless shelters, and public health center nurses for dosshouse people. Results: The results were 4 themes and 15 sub-themes: Characteristics of HSRs, perception of health and health problem of HSRs (alcohol related disease, hypertension Diabetics, gastro-intestinal disease, dental disease and infectios disease such as Tuberculosis, musculo-skeletal disease, prostate problem), health care status of HSRs(insufficient health care service, discrimination of medical staff, lack of health care management, low satisfaction community health care services), and the health care proposal of HSRs(nurse in homeless shelter, integrated health care system, understanding of homeless) Conclusion: Based on the findings of this study, health care programs focusing on understanding of HSRs and chronic diseases of HSRs increasing steadily although the management system is limited. Therefore, more systemized health care plan and health referral system for homeless people.

Nursing Students' Experience in Community Health Center Practice (간호학생의 보건진료소 실습경험)

  • Park, Hyun-Joo;Jang, In-Sun
    • Research in Community and Public Health Nursing
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    • v.21 no.2
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    • pp.188-199
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    • 2010
  • Purpose: The objective of this study was to understand the meaning of experience on community health centers (post) practice of nursing students. Methods: This is qualitative research using focus groups. Data were collected through in-depth interviews performed from November 10 to December 11, 2009. The focus group interviews were conducted to 22 nursing students on their subjective experiences. The data were analyzed by the Colaizzi's method, in which the meaningful statements were extracted. Results: Seven theme-clusters were identified from fourteen themes and thirty-one sub-themes. The seven theme-clusters were 1) widening of experiences; 2) feeling of warm heart; 3) feeling of satisfaction; 4) feeling of being unfulfilled; 5) difficulties; 6) new awareness; and 7) good memories. Conclusion: Through a variety of relationships and self-regulation in community health centers (post) practice, the nursing students may have the feeling of worthiness, new awareness of community nursing, and visions for the future to rebuild.

A Study on Activation Plans of Flexible Work Arrangements Based on a Qualitative Case Study of a Foreign-affiliated Firm (외국계기업사례분석을 통한 유연근무제활성화방안 연구)

  • Lee, Hyun-Ah;Kim, Sun-Mi;Lee, Seung-Mi
    • Journal of Families and Better Life
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    • v.30 no.2
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    • pp.173-187
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    • 2012
  • This qualitative case study focused on the activation plan of flexible work arrangements. We selected eight workers from a foreign affiliated firm that has various flexible work arrangements for in-depth interview and focus group interview. The workers were categorized into two groups; those who have experiences with flexible working and those who have needs for flexible working. We analyzed their condition of work-family life and experiences with flexible working. Through the focus group interview, we can find out the needs and suggestions about activation plans of flexible work arrangements.

Effect of Process Parameters on Bead Formation in Nd:YAG Laser Welding of Thin Steels (저탄소 박판 강재의 Nd:YAG 레이저 용접부 형성에 미치는 공정변수의 영향)

  • 김기철;허재협
    • Journal of Welding and Joining
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    • v.19 no.3
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    • pp.317-324
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    • 2001
  • This study deals with high power Nd:YAG laser welding of thin steels for small pressure vessels. Full penetration welding at the overlap joint was performed so as to assure sufficient weld strength. Results showed that mid-depth weld size reduced drastically with increasing the travel speed. Position of focus had little effect on the bead formation even though short focal system was used. However, the shape factor and the bead width had closely related with the position of focus. Based on the microstructural inspection, acceptable weld was obtained when the overlap clearance was controlled up to 20% of the base metal thickness. In the case that the joint contained more clearance than the critical value, both the tensile shear strength and the tear strength were reduced. Results also demonstrated that shielding gases were proved to play a key role as far as the bead formation characteristics was taken into consideration. Blowing dry air through 5mm in diameter nozzle produced narrower bead cross-section than that of argon or nitrogen shielding.

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Mothers' perceptions of children's food behaviors: use of focus group interview study

  • Lee, Young-Mee;Kim, Jung-Hyun;Oh, Yu-Jin;Lee, Min-June
    • Nutrition Research and Practice
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    • v.2 no.4
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    • pp.259-268
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    • 2008
  • Children's food behaviors have been expressed in a various ways because of recent changes in their family environment. Thus, this study was performed to investigate in-depth qualitative research on the mother's perception on children's food behaviors by focused group interview. This study was designed in four steps of planning, collection of participants, process, and analysis. Participants for the focus group interview were recruited and sampled from households with elementary school students in the Seoul and Gyeonggido areas. Groups were divided by total income and education expense levels. 1) High income household: It is better to improve currently existing web sites for nutrition education. 2) Mid income household: Easy, practical, and inexpensive off-line cooking class/nutrition education classes for mothers are needed. Nutrition programs for children should be developed through mass media and be promoted in the broadcasting circle. 3) Low income household: Motivation is required for mothers' educatior and the serious nutritional problems of children should be informed through mass media and home correspondence from school. And interesting educational materials should be developed for children to read whenever they want.

Plus-size Women and Appearance Management with a Focus on Clothing -Grounded Theory Based Exploratory Study- (근거이론에 기초한 플러스 사이즈 여성 소비자의 의류를 중심으로 한 외모관리에 관한 탐색적 연구)

  • Yu, Haekyung;Ko, Sunyoung;Kim, Chanju
    • Journal of the Korean Society of Clothing and Textiles
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    • v.37 no.3
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    • pp.306-319
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    • 2013
  • This study explores various issues of appearance management behavior for plus-size women in Korea with a focus on clothing. In-depth interviews and focused group interviews were conducted with 24 plus-size women. The interviews were recorded and the transcripts were analyzed based on grounded theory. Discomfort was the main phenomenon involving the experience of plus-size women related to appearance management. Psychological as well as physiological/physical discomfort, unmet needs (regarding clothing) and inconvenient shopping experiences were frequently mentioned. Causal conditions for discomfort were obesity, social stigma, and an underdeveloped clothing market for plus-size consumers. Interviewees developed strategies to cope with discomfort (suppressing clothing need, loss of interest in clothing, diversion from clothing needs, sole focus on physical comfort, dress-up and increase in shopping channels, and change in shopping patterns) that depended on contextual conditions (such as duration of obesity and attitudes of people) close to the interviewees. The discomfort of interviewees decreased or continued depending on if they became ambivalent about their obese condition, lost weight, or utilized plus-size specialty stores.

Study on Surface Damage of Specimen for Transmission Electron Microscopy(TEM) Using Focused Ion Beam(FIB) (집속 이온빔을 이용한 투과 전자 현미경 시편의 표면 영향에 관한 연구)

  • Kim, Dong-Sik
    • 전자공학회논문지 IE
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    • v.47 no.2
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    • pp.8-12
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    • 2010
  • TEM is a powerful tool for semiconductor material analyses in structure or biological sample in micro structure. TEM observation need to make to coincide specimens for special purpose. in this paper, we have experimented for minimum surface damage on bulk wafer and patterned specimen by various conditions such as accelerating energy, depth of ion beam, ion milling types, and etc. in various specimen preparation methods by FIB (Focus Ion Beam). The optimal qualified specimens are contain low mounts of surface damage(about 5 nm) on patterned specimen.

Consumer Values and Green Consumption: Implications for Marketing Strategy and Environmental Policy

  • Lee, Hyun Ju;Park, Seong-Yeon
    • Asia Marketing Journal
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    • v.19 no.4
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    • pp.87-114
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    • 2018
  • The objective of this study is to find the effects of consumer values on eco-friendly buying behavior. This study examines environmental attitudes and involvement as moderating variables to explain eco-friendly buying behavior of consumers. Hypotheses were developed based on Focus Group Interviews, Depth Interviews, and literature reviews. To test such hypotheses, questionnaires were distributed and collected among female adults aged 18 or above, and who are either office workers or housewives. The analysis results show that personal values, sociocultural values, and values related to ecofriendly products affect consumers in their eco-friendly buying behavior. Among those values, concern about safety and health, eco-friendly culture and trend, willingness to pay price premiums and functional effects of eco-friendly products have significant effects on eco-friendly buying behavior. Reflecting these results, business marketers must appeal to consumers with more focus on safety and health, perceived consumer effectiveness, self-monitoring, eco-friendly culture and trend, media exposure, willingness to pay price premiums, design excellence and functional effects, to implement marketing communication strategies accordingly.

Hybrid Down-Sampling Method of Depth Map Based on Moving Objects (움직임 객체 기반의 하이브리드 깊이 맵 다운샘플링 기법)

  • Kim, Tae-Woo;Kim, Jung Hun;Park, Myung Woo;Shin, Jitae
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37A no.11
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    • pp.918-926
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    • 2012
  • In 3D video transmission, a depth map being used for depth image based rendering (DIBR) is generally compressed by reducing resolution for coding efficiency. Errors in resolution reduction are recovered by an appropriate up-sampling method after decoding. However, most previous works only focus on up-sampling techniques to reduce errors. In this paper, we propose a novel down-sampling technique of depth map that applies different down-sampling rates on moving objects and background in order to enhance human perceptual quality. Experimental results demonstrate that the proposed scheme provides both higher visual quality and peak signal-to-noise ratio (PSNR). Also, our method is compatible with other up-sampling techniques.