• Title/Summary/Keyword: semi-convergence

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The Study on Applicability of Semi-conductive Compound for Radioactive Source Tracing Dosimeter in NDT Field (비파괴 검사 분야의 방사성 동위원소 위치추적을 위한 반도체 화합물의 적용 가능성 연구)

  • Shin, Yohan;Han, Moojae;Jung, Jaehoon;Kim, Kyotae;Heo, Yeji;Lee, Deukhee;Cho, Heunglae;Park, Sungkwang
    • Journal of the Korean Society of Radiology
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    • v.13 no.1
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    • pp.39-44
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    • 2019
  • Radiation safety management is being considered very important since radioactive isotopes such as Co-60 and Ir-192 are widely used in fields such as non-destructive test(NDT). In this study, the applicability of Mercury(II) Iodide($HgI_2$) source for tracing system was evaluated. To make sure the unit cell sensor's reliability, we evaluated the electrical properties of the sensor made with $HgI_2$, and then position dependence of the sensor was analyzed and compared with the dose distribution from the planning system. As a result of the evaluation, high reliability of the sensor was shown through the linearity of R-sq > 0.990 and reproducibility of CV < 0.015. In the position dependence evaluation, the maximum value was measured at the isocenter of the sensor and gradually decreased according to the distance. However, the dose distribution data from the planning system was turned out that has difference with that of the sensor up to 30%. This seems to come from the difference between single-point measuring based planning system and area measuring based sensor.

A Survey on the Purchase and Preference of Golf Wear for Men and Women in Their 40s, 50, and 60s (40~60대 남녀의 골프웨어 구매 및 선호실태조사)

  • Kyung Ja Paek
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.4
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    • pp.727-737
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    • 2023
  • This study aimed to provide basic data for the design and R&D of golf wear intended for 64 people in their 40s, 50s, and 60s by identifying the needs for golfers through a survey of golf wear purchasing conditions and preferences. The findings shows that purchases are made at permanent discount stores, and information about products are discovered through TV and Internet advertisements. Golf wear is purchased once or twice a year, with annual expenditures ranging from KRW 500,000 to less than 1 million, with single purchases ranging from KRW 200,000 to less than 500,000. When purchasing golf wear, design was considered first, with women preferring white garment, while men preferred black and gray ones. Men tended to prefer a PK collar button fastening style, while women preferred a knit style with a round neckline. Women preferred semi-fitted and fitted styles, while men preferred semi-fitted and loose-fitting styles, showing significant differences. When considering the production of golf wear, the younger the age of the consumer, the more the results indicated that the design needed to look younger, so it is the necessary to design golf wear that reflects the functional need of golfer while prioritizing designs for various ages.

Men's fathering experiences focused on tensions and conflict of multiple roles (아버지의 부성경험: 다양한 역할수행의 긴장과 갈등)

  • Yang, Sonam
    • Journal of Digital Convergence
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    • v.11 no.2
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    • pp.375-383
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    • 2013
  • The aim of this study is to explore fathers' own expectations and experiences of fatherhood along with their views of what it meant to be a 'good' father. Qualitative methodologies were used; semi-structured in-depth interviews with 10 dual-earner fathers with young children. Interviewees overwhelmingly welcomed the opportunities offered to them by the new fatherhood model and supported a perceived cultural shift towards men and fathers being involved in, rather than detached from, family life. However tension and difficulty in living the ideal were also reported: gaps between perceptions and behaviors; struggle for traditional breadwinning role and caring; conflicts between selflessness and career and uninvolved in family decisions. Political and practical considerations are discussed, and the implications of this study for future research are identified.

Experimental Study on Elastic Response of Circular Cross-section Slender Body to Forced Oscillation, Waves, and Current (복합 외력환경 중 원형 단면 세장체의 탄성응답에 관한 실험적 연구)

  • Park, Ji-won;Lee, Seung-Jae;Jo, Hyo-Jae;Hwang, Jae-Hyuk;Han, Sung-Hoon
    • Journal of Ocean Engineering and Technology
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    • v.30 no.2
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    • pp.91-99
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    • 2016
  • The global demand for oil and natural gas has increased, and resource development is moving to the deep sea. Floating and flexible offshore structures such as semi-submersible, spar, and FPSO structures have been widely used. The major equipment of floating structures is always exposed to waves, currents, and other marine environmental factors, which cause structural damage. Moreover, flexible risers are susceptible to an exciting force due to the motion of the floating body. The inline and transverse responses from the three-dimensional behavior of a floating structure occur because of various forces. Typical risers are made of steel pipe and applied in the oil and gas development field, but flexible materials such as polyethylene are suitable for OTEC risers. Consequently, the optimal design of a flexible offshore plant requires a dynamic behavior analysis of slender bodies made of the different materials commonly used for offshore flexible risers. In this study, a three-dimensional motion measurement device was used to analyze the displacements of riser models induced by external force factors, and forced oscillation of a riser was linked to forced oscillation under a steady flow and regular wave condition.

Systematic Gathering & Migration to integrate Heterogeneous Railway Information (이형적인 철도정보 통합을 위한 데이터 수집 및 마이그레이션 (반)자동화 방안)

  • Shon, Woo-Yong;An, Tae-Ki;Ahn, Chi-hyung;Lee, Won-Goo
    • Journal of Digital Convergence
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    • v.14 no.5
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    • pp.283-291
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    • 2016
  • The railroad is one of the most popular means of transport. However, railroad agencies are managing the railroad information and provide its service respectively. That is, because of managing the different information and its type, the user will not receive the correct and integrated information. Thus, it is needed to employ methods for converting the various types of railroad information into the unified railroad information. In this study, we investigated how to (semi-)automatically convert railroad information in each agencies to standard railroad information. Railroad passengers can use the railroad information service at a time, at a glance and in one place. In addition, we believe that there can be provided the opportunity to create an new service, which will dramatically develop a railroad information service through these systematic and integrated railroad information management.

Window Production Method based on Low-Frequency Detection for Automatic Object Extraction of GrabCut (GrabCut의 자동 객체 추출을 위한 저주파 영역 탐지 기반의 윈도우 생성 기법)

  • Yoo, Tae-Hoon;Lee, Gang-Seong;Lee, Sang-Hun
    • Journal of Digital Convergence
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    • v.10 no.8
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    • pp.211-217
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    • 2012
  • Conventional GrabCut algorithm is semi-automatic algorithm that user must be set rectangle window surrounds the object. This paper studied automatic object detection to solve these problem by detecting salient region based on Human Visual System. Saliency map is computed using Lab color space which is based on color opposing theory of 'red-green' and 'blue-yellow'. Then Saliency Points are computed from the boundaries of Low-Frequency region that are extracted from Saliency Map. Finally, Rectangle windows are obtained from coordinate value of Saliency Points and these windows are used in GrabCut algorithm to extract objects. Through various experiments, the proposed algorithm computing rectangle windows of salient region and extracting objects has been proved.

Suggestions for Building 'Smart Campus' Based on Case Studies on the Effectiveness of Instructions with Smart-Pads (스마트 패드 활용수업 사례분석에 기반한 스마트 캠퍼스 구축 발전방향)

  • Park, Sung-Youl;Lim, Keol
    • Journal of Digital Convergence
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    • v.10 no.3
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    • pp.1-12
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    • 2012
  • According to recent trends of ubiquitous learning with the advent of smart devices, this study was to suggest for the successful achievement of "Smart Campus" initiatives by experiencing an instruction with smart-pads (tablet PCs) in a university. A pilot project was conducted as a part of building a Smart Campus in S university in Gyeong-gi Province in Korea for the study. The class was held in the Summer semester in 2011 with six participants. Using research methodologies such as semi-structured interviews and stimulated recall, perceived academic performances, satisfaction, and the usability of smart-pads were analysed. Main results included high perceived academic performances, satisfaction, and the usability, however, some negative responses also detected on the variables. Based on the results, it was suggested that specific instructional strategies should be developed in terms of hardware, software and humanware.

Object VR-based Virtual Textile Wearing System Using Textile Texture Mapping (직물 텍스쳐 매핑을 이용한 객체 VR 기반 가상 직물 착용 시스템)

  • Kwak, No-Yoon
    • Journal of Digital Convergence
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    • v.10 no.8
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    • pp.239-247
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    • 2012
  • This paper is related to an Object VR-based virtual textile wearing system carrying out textile texture mapping based on viewpoint vector estimation and intensity difference map. The proposed system is characterized as capable of virtually wearing a new textile pattern selected by the user to the clothing shape section segmented from multi-view 2D images of clothes model for Object VR(Object Virtual Reality), and three-dimensionally viewing its virtual wearing appearance at multi-view points of the object. Regardless of color or intensity of model clothes, the proposed system is possible to virtually change the textile pattern with holding the properties of the selected clothing shape section, and also to quickly and easily simulate, compare, and select multiple textile pattern combinations for individual styles or entire outfits. The proposed system can provide higher practicality and easy-to-use interface, as it makes real-time processing possible in various digital environment, and creates comparatively natural and realistic virtual wearing styles, and also makes semi-automatic processing possible to reduce the manual works.

A Study of improving reliability on prediction model by analyzing method Big data (빅데이터 분석방법을 이용한 예측모형의 신뢰도 향상에 관한 연구)

  • Song, Min-Gu;Kim, Sun-Bae
    • Journal of Digital Convergence
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    • v.11 no.6
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    • pp.103-112
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    • 2013
  • Traditional method of establishing prediction model is usually using formal data stored in Data Base. However, nowadays advent of "smart" era brought by ground-breaking development of communication system makes informal data to dominate overall data, such 80% in total. Therefore, conventional method using formal data as establishing predicting model would be untrustworthy means in present. In other words, it is indispensible to make prediction model credible including informal data(SNS, image, video) and semi-formal data(log data). In this study, we increase credibility of predicting model adapting Bigdata method and comparing reliability of conventional measurement to real-data.

Performance Evaluation of a Time-domain Gauss-Newton Full-waveform Inversion Method (시간영역 Gauss-Newton 전체파형 역해석 기법의 성능평가)

  • Kang, Jun Won;Pakravan, Alireza
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.26 no.4
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    • pp.223-231
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    • 2013
  • This paper presents a time-domain Gauss-Newton full-waveform inversion method for the material profile reconstruction in heterogeneous semi-infinite solid media. To implement the inverse problem in a finite computational domain, perfectly-matchedlayers( PMLs) are introduced as wave-absorbing boundaries within which the domain's wave velocity profile is to be reconstructed. The inverse problem is formulated in a partial-differential-equations(PDE)-constrained optimization framework, where a least-squares misfit between measured and calculated surface responses is minimized under the constraint of PML-endowed wave equations. A Gauss-Newton-Krylov optimization algorithm is utilized to iteratively update the unknown wave velocity profile with the aid of a specialized regularization scheme. Through a series of one-dimensional examples, the solution of the Gauss-Newton inversion was close enough to the target profile, and showed superior convergence behavior with reduced wall-clock time of implementation compared to a conventional inversion using Fletcher-Reeves optimization algorithm.