• Title/Summary/Keyword: Lock system

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Efficient Processing of Grouped Aggregation on Non-Uniformed Memory Access Architecture (비균등 메모리 접근 구조에서의 효율적인 그룹화 집단 연산의 처리)

  • Choe, Seongjun;Min, Jun-Ki
    • Database Research
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    • v.34 no.3
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    • pp.14-27
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    • 2018
  • Recently, to alleviate the memory bottleneck problme occurred in Symmetric Multiprocessing (SMP) architecture, Non-Uniform Memory Access (NUMA) architecture was proposed. In addition, since an aggregation operator is an important operator providing properties and summary of data, the efficiency of the aggregation operator is crucial to overall performance of a system. Thus, in this paper, we propose an efficient aggregation processing technique on NUMA architecture. Our proposed technique consists of partition phase and merge phase. In the partition phase, the target relation is partitioned into several partial relations according to grouping attribute. Thus, since each thread can process aggregation operator on partial relation independently, we prevent the remote memory access during the merge phase. Furthermore, at the merge phase, we improve the performance of the aggregation processing by letting each thread compute aggregation with a local hash table as well as avoiding lock contention to merge aggregation results generated by all threads into one.

A Study on the Change of Spatial Structures of Shared Space at Urban Campuses - The opposite concept of Gridlock upon the change to shared campuses - (도심 캠퍼스 공유공간의 공간 구조 변화에 대한 연구 - 그리드락의 반대 개념으로서의 공유 캠퍼스로의 변화에 대하여 -)

  • Kang, Eunki;Baek, Jin
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.34 no.11
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    • pp.145-156
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    • 2018
  • Urban campus, one of the main urban facilities, is the representative place that is struggling with 'gridlock'. Due to privatization of space among different departments and space shortages, gridlock has been occurring as a result. The urban campus trying to solve this problem by changing the quality of space, especially the structure of the shared space, which is expected to be the solution to the grid lock problem. The main purpose of this study is to investigate the structural change in the university's shared space based on paradigm transition. The theoretical consideration is to analyze the spatial characteristics of university shared space that appear at different stages through a new perspective that compares the gridlock phenomenon and the shared paradigm. The framework of the analysis of the shared space, which has recently been restructured, is classified into the spatial characteristics of collaborative space, the creative space, and the common/complex space. In addition, these spatial characteristics are again analyzed through the division of legislative facility classification, management governance subject, area, building location and layout, exposure to the outside as well as the analysis of student and staff entry and exit, sharing structure of site and space, and the classification of program characteristics. The results are as follows: The restructured space is systemized so that the management governance of each space would be connected to each other to share information and space. Furthermore, the spatial boundary between colleges or between campus spaces are not only physically, but categorically clear. The restructured space has semi (or in-between)-spatial characteristics such as the intersection in inside and outside of the pedestrian's circulation and the mixture of programs. This study could serve as principal references in presenting the systematic analysis of directions of the shared spatial structure for the urban campus where new educational space is required due to the changes in the university system.

A Study on the Effect of Network Activity Characteristics on the Technological Innovation Performance: Focused on Relational Capital, Industry-University Linkage and Informal Exchange (네트워크 활동 특성이 R&D 수행기업의 기술혁신 성과에 미치는 영향에 대한 연구 : 관계자본, 산학연 연계, 비공식교류를 중심으로)

  • Sim, Seong-Hag;Seo, Hwan-Joo
    • Asia-Pacific Journal of Business
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    • v.10 no.4
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    • pp.49-63
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    • 2019
  • The export regulation of semiconductor core materials, which began with the recent revision of the export management regulations of Japan, raises the need for a new cooperation network. A hierarchical management network that was effective in the fast-follower system requires organic cooperation between the public sector and industry through a multilateral network that emphasizes horizontal co-operation among innovation actors. This study focused on the relational capital that exists among members of a business association such as an association that has been relatively marginalized from previous studies. In addition, this study aimed to analyze the effect of network activity characteristics such as industry-university linkage and informal exchange on technological innovation. Through this, I would like to draw implications for enhancing the effectiveness of the government's R & D support and innovation performance of R & D companies. Based on the results of the SMEs R & D survey, this study found that relational capital, informal exchange had a positive effect on technological innovation performance. However, if the relational capital exceeds a certain level, it is analyzed that there is a negative effect due to group think and lock-in effect. This means that informal exchange channels should be expanded for innovation and enhancement, and relational capital should be managed in consideration of the negative effects that may occur when certain levels are exceeded.

Development and feasibility test of sit-to-stand transfer assistive device

  • Ha, SinHo;Jeong, SeYeon;Hong, SoungKyun;Choi, Wonjae;Lee, Kwangkook;Park, Donghwan;Son, SangJun;Shin, HyeonHui;Lee, GyuChang
    • Journal of Korean Physical Therapy Science
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    • v.29 no.1
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    • pp.41-46
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    • 2022
  • Background: The purpose of this study was to develop a sit-to-stand transfer assistive device, and to conduct a feasibility test. Design: A technical note. Methods and results: In this study, we developed a sit-to-stand transfer assistive device for the elderly and the disabled who have difficulty standing up independently from sitting positions. The sit-to-stand transfer assistive device allows the user to transfer the weight from a sitting position to a standing position while shifting the weight forward by grabbing and pulling a support stand. Ten healthy adults participated in the feasibility test of the device. Each participant used the developed sit-to-stand transfer assistive device and investigated supplementation through a brief interview. As a result of the feasibility test, the opinion was that the device could assist the sit-to-stand transfer to some extent. There were opinions that it needed a function to adjust the height of the knee protective plate in the sitting position according to the user's physical characteristics. Because of the inconvenience of operating the lock device for fixing the position and adjusting inclination, there was an opinion that the improvement for a locking device is needed. There were opinions that it would be better to reduce the size of the device due to its inconvenience of portability. Conclusion: In this study, we developed the sit-to-stand transfer assistive device for the elderly and the disabled who have difficulty standing up independently from sitting positions. In addition, it is considered that the upgrade of the device is necessary for the future since there are supplementary opinions on some points.

An Input Method for Decimal Password Based on Eyeblink Patterns (눈깜빡임 패턴에 기반한 십진 패스워드 입력 방법)

  • Lee, Seung Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.5
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    • pp.656-661
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    • 2022
  • Password with a combination of 4-digit numbers has been widely adopted for various authentication systems (such as credit card authentication, digital door lock systems and so on). However, this system could not be safe because the 4-digit password can easily be stolen by predicting it from the fingermarks on the keypad or display screen. Furthermore, due to the prolonged COVID-19 pandemic, contactless method has been preferred over contact method in authentication. This paper suggests a new password input method based on eyeblink pattern analysis in video sequence. In the proposed method, when someone stands in front of a camera, the sequence of eyeblink motions is captured (according to counting signal from 0 to 9 or 9 to 0), analyzed and encoded, producing the desired 4-digit decimal numbers. One does not need to touch something like keypad or perform an exaggerated action, which can become a very important clue for intruders to predict the password.

A Study on the estimation of traffic congestion for Pyeongtaek·Dangjin port development (평택·당진항의 내항개발에 따른 교통혼잡도 평가에 관한 연구)

  • Gug Seung-Gi;Kim Se-Won;Kim Jung-Hoon
    • Journal of Navigation and Port Research
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    • v.29 no.6 s.102
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    • pp.481-485
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    • 2005
  • The port entry system of the inner harbor in Pyeongtaek${\cdot}$Dangjin was planned as lock-gate in 'Master plan project on port planning in Asan industry base(1990)‘, but was changed to tidal harbor in 'Project maintaining Master plan for comprehensive development of Pyeongtaek${\cdot}$Dangjin port(2001)'. Accordingly, southern sea bank constructed under the lower part of Seohae-bridge will be removed so that inbound/outbound vessels for the inner harbor can navigate at all times. However, in the view of the safety on passing through the lower of Seohae-bridge, navigating conditions for the inner harbor will be restricted in the single-way of 50,000 DWT vessel and the two-way of vessel less than 30,000 DWT Therefore, this study carried out the estimation of traffic congestion arising from these vessels with above restrictions q[ter supposing annual inbound/outbound vessel's numbers for loading and unloading cargo surveyed on the inner harbor.

A Study on the estimation of traffic congestion for Pyeongtaek (Asan) port development (평택(아산)항 개발에 따른 교통혼잡도 평가에 관한 연구)

  • Kuk, Seung-Gi;Kim, Se-Won;Kim, Jeong-Hoon
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.29 no.1
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    • pp.191-195
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    • 2005
  • The port entry system of the inner harbor in Pyeongtaek (Asan) was planned as lock-gate in 'Master plan project on port planning in Asan industry base(1990)', but was changed to tidal harbor in 'Project maintaining Master Plan for comprehensive development of Pyeongtaek (Asan) port(2001)'. Accordingly, southern sea bank constructed under the lower part of Seohae-bridge will be removed so that inbound/outbound vessels for the inner harbor can navigate at all times. However, in the view of the safety on passing through the lower of Seohae-bridge, navigating conditions for the inner harbor will be restricted in the single-way of 50,000 DWT vessel and the two-day of vessel less than 30,000 DWT. Therefore, this study carried out the estimation of traffic congestion arising from these vessels with above restrictions after supposing annual inbound/outboubd vessel's numbers for loading and unloading cargo surveyed on the inner harbor.

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Taxonomy of Performance Shaping Factors for Human Error Analysis of Railway Accidents (철도사고의 인적오류 분석을 위한 수행도 영향인자 분류)

  • Baek, Dong-Hyun;Koo, Lock-Jo;Lee, Kyung-Sun;Kim, Dong-San;Shin, Min-Ju;Yoon, Wan-Chul;Jung, Myung-Chul
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.31 no.1
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    • pp.41-48
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    • 2008
  • Enhanced machine reliability has dramatically reduced the rate and number of railway accidents but for further reduction human error should be considered together that accounts for about 20% of the accidents. Therefore, the objective of this study was to suggest a new taxonomy of performance shaping factors (PSFs) that could be utilized to identify the causes of a human error associated with railway accidents. Four categories of human factor, task factor, environment factor, and organization factor and 14 sub-categories of physical state, psychological state, knowledge/experience/ability, information/communication, regulation/procedure, specific character of task, infrastructure, device/MMI, working environment, external environment, education, direction/management, system/atmosphere, and welfare/opportunity along with 131 specific factors was suggested by carefully reviewing 8 representative published taxonomy of Casualty Analysis Methodology for Maritime Operations (CASMET), Cognitive Reliability and Error Analysis Method (CREAM), Human Factors Analysis and Classification System (HFACS), Integrated Safety Investigation Methodology (ISIM), Korea-Human Performance Enhancement System (K-HPES), Rail safety and Standards Board (RSSB), $TapRoot^{(R)}$, and Technique for Retrospective and Predictive Analysis of Cognitive Errors (TRACEr). Then these were applied to the case of the railway accident occurred between Komo and Kyungsan stations in 2003 for verification. Both cause decision chart and why-because tree were developed and modified to aid the analyst to find causal factors from the suggested taxonomy. The taxonomy was well suited so that eight causes were found to explain the driver's error in the accident. The taxonomy of PSFs suggested in this study could cover from latent factors to direct causes of human errors related with railway accidents with systematic categorization.

A Comparative Study of Korean Home Economic Curriculum and American Practical Problem Focused Family & Consumer Sciences Curricula (우리나라 가정과 교육과정과 미국의 실천적 문제 중심 교육과정과의 비교고찰)

  • Kim, Hyun-Sook;Yoo, Tae-Myung
    • Journal of Korean Home Economics Education Association
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    • v.19 no.4
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    • pp.91-117
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    • 2007
  • This study was to compare the contents and practical problems addressed, the process of teaching-learning method, and evaluation method of Korean Home Economics curriculum and of the Oregon and Ohio's Practical Problem Focused Family & Consumer Sciences Curricula. The results are as follows. First, contents of Korean curriculum are organized by major sub-concepts of Home Economics academic discipline whereas curricular of both Oregon and Ohio states are organized by practical problems. Oregon uses the practical problems which integrate multi-subjects and Ohio uses ones which are good for the contents of the module by integrating concerns or interests which are lower or detailed level (related interests). Since it differentiates interest and module and used them based on the basic concept of Family and Consumer Science, Ohio's approach could be easier for Korean teachers and students to adopt. Second, the teaching-learning process in Korean home economics classroom is mostly teacher-centered which hinders students to develop higher order thinking skills. It is recommended to use student-centered learning activities. State of Oregon and Ohio's teaching-learning process brings up the ability of problem-solving by letting students clearly analyze practical problems proposed, solve problems by themselves through group discussions and various activities, and apply what they learn to other problems. Third, Korean evaluation system is heavily rely on summative evaluation such as written tests. It is highly recommended to facilitate various performance assessment tools. Since state of Oregon and Ohio both use practical problems, they evaluate students mainly based on their activity rather than written tests. The tools for evaluation include project documents, reports of learning activity, self-evaluation, evaluation of discussion activity, peer evaluation in a group for each students for their performance, assessment about module, and written tests as well.

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The Development and Utilization of I_smart_keeper for the Learner's Smart Phone Control (학습자의 스마트폰 제어를 위한 아이스마트키퍼 개발 및 적용)

  • Han, Kyujung;Heo, Jaeyoung
    • Journal of The Korean Association of Information Education
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    • v.17 no.3
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    • pp.253-264
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    • 2013
  • We development the service that teacher and parent can control the smart phone of student in school and home, the name is I_smart_keeper. The service is composed of server system, teacher's application, parent's application and student's application. The control of student's phone in school is operated by school timetable and GPS(Global Positioning System) in smart phone. The student's phone is operating one of six policy. The six policy is 'emergency call only', 'specific application only', 'call only', 'call and text only', 'all allowed' and 'all lock'. The teacher can change the current policy with his or her phone, That is a the temporary policy can be applied on a day. In school hours, teacher is able to instruct student using application appropriate to the teaching. If student is leaving school early and located outside school, the service do free the student's phone by GPS of her or his phone. We show the Smart Health Indicator (SHI)that analyse the pattern of student's phone habit and SHI will guide a desirable student's phone habit. In home, parent can control child's phone. The service will help the risk reduction of a robbery case due to keeping student's phone by teacher in class. Currently one elementary school's all student use I_smart_keeper and three elementary school is testing to some class. The teacher's impression was very good and they usually use I_smart_keeper for class in positive light. Survey results for students with higher satisfaction.