• Title/Summary/Keyword: open set

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Priority Analysis of Cause Factors of Safety Valve Failure Mode Using Analytical Hierarchy Process (AHP를 활용한 안전밸브(PSV) 고장모드의 Cause Factors 우선순위 분석)

  • Kim, Myung Chul;Lee, Mi Jeong;Lee, Dong Geon;Baek, Jong-Bae
    • Korean Chemical Engineering Research
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    • v.60 no.3
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    • pp.347-355
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    • 2022
  • The safety valve (PSV) is a safety device that automatically releases a spring when the pressure generated by various causes reaches the set pressure, and is restored to a normal state when the pressure falls below a certain level. Periodic inspection and monitoring of safety valves are essential so that they can operate normally in abnormal conditions such as pressure rise. However, as the current safety inspection is performed only at a set period, it is difficult to ensure the safety of normal operation. Therefore, evaluation items were developed by finding failure modes and causative factors of safety valves required for safety management. In addition, it is intended to provide decision-making information for securing safety by deriving the priority of items. To this end, a Delphi survey was conducted three times to derive evaluation factors that were judged to be important in relation to the Failure Mode Cause Factor (FMCFs) of the safety valve (PSV) targeting 15 experts. As a result, 6 failure modes of the safety valve and 22 evaluation factors of its sub-factors were selected. In order to analyze the priorities of the evaluation factors selected in this way, the hierarchical structure was schematized, and the hierarchical decision-making method (AHP) was applied to the priority calculation. As a result of the analysis, the failure mode priorities of FMCFs were 'Leakage' (0.226), 'Fail to open' (0.201), 'Fail to relieve req'd capacity' (0.152), 'Open above set pressure' (0.149), 'Spuriously' 'open' (0.146) and 'Stuck open' (0.127) were confirmed in the order. The lower priority of FMCFs is 'PSV component rupture' (0.109), 'Fail to PSV size calculation' (0.068), 'PSV Spring aging' (0.065), 'Erratic opening' (0.059), 'Damage caused by improper installation and handling' (0.058), 'Fail to spring' (0.053), etc. were checked in the order. It is expected that through efficient management of FMCFs that have been prioritized, it will be possible to identify vulnerabilities of safety valves and contribute to improving safety.

2D Artificial Data Set Construction System for Object Detection and Detection Rate Analysis According to Data Characteristics and Arrangement Structure: Focusing on vehicle License Plate Detection (객체 검출을 위한 2차원 인조데이터 셋 구축 시스템과 데이터 특징 및 배치 구조에 따른 검출률 분석 : 자동차 번호판 검출을 중점으로)

  • Kim, Sang Joon;Choi, Jin Won;Kim, Do Young;Park, Gooman
    • Journal of Broadcast Engineering
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    • v.27 no.2
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    • pp.185-197
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    • 2022
  • Recently, deep learning networks with high performance for object recognition are emerging. In the case of object recognition using deep learning, it is important to build a training data set to improve performance. To build a data set, we need to collect and label the images. This process requires a lot of time and manpower. For this reason, open data sets are used. However, there are objects that do not have large open data sets. One of them is data required for license plate detection and recognition. Therefore, in this paper, we propose an artificial license plate generator system that can create large data sets by minimizing images. In addition, the detection rate according to the artificial license plate arrangement structure was analyzed. As a result of the analysis, the best layout structure was FVC_III and B, and the most suitable network was D2Det. Although the artificial data set performance was 2-3% lower than that of the actual data set, the time to build the artificial data was about 11 times faster than the time to build the actual data set, proving that it is a time-efficient data set building system.

DMGL: An OpenGL ES Based Mobile 3D Rendering Libraries (DMGL: OpenGL ES 기반 모바일 3D 렌더링 라이브러리)

  • Hwang, Gyu-Hyun;Park, Sang-Hun
    • Journal of Korea Multimedia Society
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    • v.11 no.8
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    • pp.1160-1168
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    • 2008
  • Recent technological innovations of mobile hardware which make it possible to implement real-time 3D rendering effects under mobile environment have provided a potential to develop realistic mobile application programs. This paper presents platform independent, OpenGL ES based, real-time mobile rendering libraries, called DMGL for supporting high quality 3D rendering on handhold devices. The libraries allows the programmers who develops mobile graphics softwares to generate varying advanced real-time 3D graphics effects without great effort. Moreover, GPGPU-based libraries give a set of functions to solve complex equations for simulating natural phenomena such as smoke and fire, and to render the results in real-time.

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Seismic evaluation and upgrading of RC buildings with weak open ground stories

  • Antonopoulos, T.A.;Anagnostopoulos, S.A.
    • Earthquakes and Structures
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    • v.3 no.3_4
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    • pp.611-628
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    • 2012
  • The inelastic earthquake response of existing, reinforced concrete buildings with an open ground story, designed according to the old Greek codes, is investigated before and after their seismic strengthening with steel braces restricted to the open ground stories. The seismic performance evaluation is based on Part 3 of Eurocode 8 for assessment and retrofitting of buildings. Three and five-story, symmetric and non-symmetric buildings are subjected to a set of seven pairs of synthetic accelerograms, compatible with the design spectrum, and conclusions are drawn regarding the effectiveness of the strengthening solutions. Seismic behavior of the selected models confirms results of previous work regarding the insufficient capacity of the open ground stories for design level earthquakes. It is also shown that strengthening only the weak ground story, a choice having the substantial advantage of low cost and continued usage of the building during its seismic retrofitting, can remove the inherent weakness without shifting the problem to the stories above and thus making such buildings at least as strong as those without a weak first story. This partial strengthening is possible for symmetric as well as eccentric buildings, in which torsion plays a further detrimental role.

A Study on the Roles of Academic Libraries for Open Access Journal Publishing: Focusing on the Academic Libraries Participated in COPE (오픈액세스 학술지 출판에서 대학도서관의 역할에 대한 고찰 - COPE 참가 대학도서관을 중심으로 -)

  • Joung, Kyoung-Hee
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.23 no.4
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    • pp.45-69
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    • 2012
  • This paper examined the roles of academic libraries in open access journal publishing in terms of monetary supports for publication. As a result, many academic libraries have participated in the cooperative programs such as COPE(Compact for Open-Access Publishing Equity) and $SCOAP^3$(The Sponsoring Consortium for Open Access Publishing in Particle Physics) for authors to publish their research in open access journals. Also, 13 academic libraries in North America have set up the campus-based open access author funds individually. Most of academic libraries in participating COPE did not fund for research that have been published in the hybrid open access journals. In addition to publication funds, academic libraries provided authors or scholarly societies with such services as copyright negotiation, technological supports of the publication process, and the dissemination of open access publications.

A Study on the Development of Curriculum for the Department of Fishing Technology in Fisheries Junior College (전문대학(專門大學) 어업과(漁業科) 교육과정(敎育課程)의 발전적(發展的) 개정(改正)에 관한 연구(硏究))

  • Chung, Heung-Ki;Song, Ji-Ho;Lee, Kil-Rae;Bae, Seok-Jae;Hong, Sung-Kun;Cho, Bong-Kon;Lee, Won-Woo;Chang, Ho-Young
    • Journal of Fisheries and Marine Sciences Education
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    • v.2 no.1
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    • pp.1-14
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    • 1989
  • The authors studied on the modification of the curriculum for the department of fishing technology in Fisheries junior college, by collecting and analyaing the references, questionaires and consultation according to the trends in industry and employment. Especially, rapid develop of the fishing technology with the modernization and automatization of fishing vessels, the present curriculum formulated in 1983 is required to be rearranged. Accordingly, the authors studied on the development of characteristic curriculum which could cultivate the professional fishing engineers. The results obtained can be summarized as follows : 1. Total open credits should be 160 credits. 2. Cultural subjects are set 32credits, 20% of total open credits, but the subjects may be choosen by the situation of each fisheries junior college. 3. Major subjects are set 128 credits with 36 subjects including the 3rd year course. 4. The proportion of the compulsory to the elective credits in the major subjects are made 1 to 2. 5. Compulsory major subjects are set 29 credits with 11 subjects during the 1st and 2nd year course. Training on the board (I) and (II) are set 40 credits during 3rd year course and evaluated as pass or not. 6. The proportion of the credits of subjects concerning to fishery and navigation is made 1 to 1. 7. In order to strengthen the computation education, the E.D.P.S. is sets 3 credits in the cultural subjects.

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Void Closing Conditions of Large Ingot by Path Schedules (대형 잉곳의 기공압착 효과 향상을 위한 폐쇄조건 연구)

  • Choi, I.J.;Choi, H.J.;Kim, D.W.;Choi, S.;Lim, S.J.
    • Transactions of Materials Processing
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    • v.19 no.8
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    • pp.480-485
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    • 2010
  • In this work, the closing behavior of cylindrical-shaped voids was experimentally investigated according to various parameters such as reduction ratio in height, initial void size and billet rotation during hot open die forging process. The reduction ratio in height, number of path, and billet rotation were chosen as key process parameters which influence the void closing behavior including the change of void shape and size. On the other hand, values of die overlapping and die width ratio were set to be constant. Void closing behavior was estimated by microscopic observation. Based on the observations, it was confirmed that application of billet rotation is more efficient to eliminate the void with less reduction ratio in height. The experimental results obtained from this study could be helpful to establish the optimum path schedule of open die forging process.

Development of Wireless License Plate Region Extraction Module Based on Raspberry Pi (라즈베리 파이를 이용한 무선 자동차번호판 영역 추출 모듈 개발)

  • Kim, Dong-Kyung;Woo, Chong-Ho
    • Journal of Korea Multimedia Society
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    • v.18 no.10
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    • pp.1172-1179
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    • 2015
  • A wireless license plate region extracting module is proposed for LPR system controlling multiple gates. This module is cheaply implemented using Raspberry Pi which is open source and high performance. First, as the upper 1/3 of the captured image is discarded as it has no useful information on license plate. Using the OpenCV libraries the edge image is got by Canny algorithm after applying Gaussian filtering to gray image, and the labeling is conducted for 4 consecutive numbers in license plate. These numbers are located using various decision equations, and expanding the numbers region the final license plate region can be extracted. The result image is transferred to Server using wifi direct. Using the proposed module it becomes easy to set up and maintain the LPR system. The experimental results showed that the successful extracting rate was 98.4% using 500 car images with 640 × 480 resolution.

A Unified Theory for Certain Weak Forms of Open Sets and Their Variant Forms

  • Roy, Bishwambhar;Seny, Ritu
    • Kyungpook Mathematical Journal
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    • v.52 no.4
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    • pp.405-412
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    • 2012
  • The purpose of the present paper is towards working out a unified version of the study of certain weak forms of generalized open sets and their neighbouring forms, as are already available in the literature. In terms of an operation, as initiated by $\acute{A}$. Cs$\acute{a}$sz$\acute{a}$r, we introduce unified definitions of ${\wedge}_{\psi}$-sets, ${\vee}_{\psi}$-sets, $g{\cdot}{\wedge}_{\psi}$-sets and $g{\cdot}{\vee}_{\psi}$-sets and derive results concerning them.

A Study on the Residential-Environment Improvement with using of unused and misused space (유휴공간 활용을 통한 주거환경 개선에 관한 연구)

  • Eun, So-Jin;Lee, Jong-Kuk
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2009.04a
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    • pp.167-172
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    • 2009
  • The purpose of this study is examine the characteristics of public open space in the office buildings located in urban commercial strip, in terms of its relationships to street, to building, and to order surrounding facilities. Theoretical basis of this research is that public outdoor spaces are to be the intermediate territory set between streets and a buildings. 5 commercial buildings in Seoul are selected as sample cases and they were closely analyzed in a comparative manner. Based on this comparison, several planning guidelines are suggested for the activation of the space, mainly in terms of the location of public open space in relation to street, the design techniques and devises reflecting the purpose of the space, and territorial arrangement and furniture layout, and the patterns of relationship to surrounding space and facilities.

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