• Title/Summary/Keyword: Technology standard model

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Effect of a Variation of a Main Duct Area on Flow Distribution of Each Branch (주덕트의 단면적 변화가 분지덕트의 유량분배에 미치는 영향)

  • Lee Jai-Ho;Kim Beom-Jun;Cho Dae-Jin;Yoon Suck-Ju
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.4
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    • pp.386-395
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    • 2005
  • With the development of a living standard, the importance of indoor air conditioning system in all kinds of buildings and vehicles has increased. A lot of researches on energy losses in a duct and various kinds of flow pattern in branches or junctions have been carried out over many years, because the primary object of a duct system used in HVAC is to provide equal flow rate in the interior of each room by minimizing pressure drop. In this study, to get equal flow distribution in each branch, a blockage is applied to the rectangular duct system. The flow analysis for flow distribution of a rectangular duct with two branches was performed by CFD. By using SIMPLE algorithm and finite volume method, flow analysis is performed in the case of 3-D, incompressible, turbulent flow. Also, the standard $k-{\varepsilon}$ model and wall function method were used for analysis of turbulent fluid flow. The distribution diagrams of static pressure, velocity vector, turbulent energy and kinetic energy in accordance with variation of Reynolds number and blockages location in a rectangular duct show that flow distribution at duct outlets is improved by a blockage. In this rectangular duct system, mean velocity and flow rate distribution in two branch outlets are nearly constant regardless of variation of Reynolds number, and a flow pattern of the internal duct has a same tendency as well.

Comparison of optical reflectance spectrum at blade and vein parts of cabbage and kale leaves

  • Ngo, Viet-Duc;Ryu, Dong-Ki;Chung, Sun-Ok;Park, Sang-Un;Kim, Sun-Ju;Park, Jong-Tae
    • Korean Journal of Agricultural Science
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    • v.40 no.2
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    • pp.163-167
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    • 2013
  • Objective of the study was to compare reflectance spectrum in the blade and the vein parts of cabbage and kale leaves. A total 6 cabbage and kale leaves were taken from a plant factory in Chungnam National University, Korea. Spectra data were collected with a UV/VIS/NIR spectrometer (model: USB2000, Ocean Optics, FL, USA) in the wavelength region of 190 - 1130 nm. Median filter smoothing method was selected to preprocess the obtained spectra data. We computed reflectance difference by subtraction of averaged spectrum from individual spectrum. To estimate correlation at different parts of cabbage and kale leaves, cross - correlation method was used. Differences between cabbage and kale leaves are clearly manifested in the green, red and near - infrared ranges. The percent reflectance of cabbage leaves in the NIR wavelength band was higher than that of kale leaves. Reflectance in the blade part was higher than in the vein part by 18%. Reflectance difference in the different parts of cabbage and kale leaves were clear in all of the wavelength bands. Standard deviation of reflectance difference in the vein part was greater for kale, while the value in the blade part was greater for cabbage leaves. Standard deviation of cross - correlation increased from 0.092 in the first sensor (UV/VIS) and 0.007 in the second sensor (NIR) to 0.099 and 0.015, respectively.

Selective Interpolation Filter for Video Coding (비디오 압축을 위한 선택적인 보간 필터)

  • Nam, Jung-Hak;Jo, Hyun-Ho;Sim, Dong-Gyu;Lee, Soo-Youn
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.49 no.1
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    • pp.58-66
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    • 2012
  • Even after establishment of H.264/AVC standard, the video coding experts group (VCEG) of ITU-T has researched on development of promising coding techniques to increase coding efficiency based on the key technology area (KTA) software. Recently, the joint collaboration team video coding (JCT-VC) which was composed of the VCEG and the motion picture experts group (MPEG) of ISO/IEC is developing a next-generation video standard namely HEVC intended to gain twice efficiency than H.264/AVC. An adaptive interpolation technique, one of various next-generation techniques, reported higher coding efficiency. However, it has high computational complexity and does not deal with various error characteristics for videos. In this paper, we investigate characteristics of interpolation filters and propose an effective fixed interpolation filter bank including diverse properties of error. Experimental results is shown that the proposed method achieved bitrate reduction by 0.7% and 1.3% compared to fixed directional interpolation filter (FDIF) of the KTA and the directional interpolation filter (DIF) of the HEVC test model, respectively.

Development of the Qualitative Model for Post Construction Evaluation (건설공사 사후평가의 정성평가 모델 개발)

  • Lee, Kyu-Sun;Park, Hee-Sung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.38 no.5
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    • pp.733-739
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    • 2018
  • Various public construction projects have been performed for public welfare and appropriate evaluation of the effectiveness and efficiency has been required. In accordance with legislation of a post construction project evaluation in Construction Technology Promotion Act, all construction projects that exceed 30 billion won in budget are required to perform post evaluation. Korean Government provides post construction evaluation manual that includes both quantitative and qualitative criteria. However, it only provides general concepts and procedures not but detail guidelines for different construction project types and characteristics. Therefore, this paper developed a standard format for qualitative evaluation using survey through analyzing previous cases and research. As a result, the developed standard for survey can be applied for most civil and architectural facilities. However, it will need further research regarding establishment of detailed evaluation criteria for each type of facilities and data storage system for feedback.

AES-128/192/256 Rijndael Cryptoprocessor with On-the-fly Key Scheduler (On-the-fly 키 스케줄러를 갖는 AED-128/192/256 Rijndael 암호 프로세서)

  • Ahn, Ha-Kee;Shin, Kyung-Wook
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.39 no.11
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    • pp.33-43
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    • 2002
  • This paper describes a design of cryptographic processor that implements the AES (Advanced Encryption Standard) block cipher algorithm "Rijndael". To achieve high throughput rate, a sub-pipeline stage is inserted into a round transformation block, resulting that two consecutive round functions are simultaneously operated. For area-efficient and low-power implementation, the round transformation block is designed to share the hardware resources for encryption and decryption. An efficient on-the-fly key scheduler is devised to supports the three master-key lengths of 128-b/192-b/256-b, and it generates round keys in the first sub-pipeline stage of each round processing. The Verilog-HDL model of the cryptoprocessor was verified using Xilinx FPGA board and test system. The core synthesized using 0.35-${\mu}m$ CMOS cell library consists of about 25,000 gates. Simulation results show that it has a throughput of about 520-Mbits/sec with 220-MHz clock frequency at 2.5-V supply.

Collaboration to Enhance Development and Application of Shiphandling Simulators

  • Shi, Chaojian;Chen, Jinbiao;Xiao, Baojia;Ding, Baocheng
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.459-464
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    • 2006
  • It has been well proved that shiphandling simulators are efficient and useful facilities for training and education of cadets and seafarers. Most of the maritime universities and many maritime training institutes all over the world have installed shiphandling simulators, which play important roles in maritime education and training. However, most of the Shiphandling simulators are standalone facilities with diversities on system architectures, layouts and functions. STCW78/95 requires simulators used for simulator-based training shall be suitable for the selected objectives and training tasks. To ensure the shiphandling simulator facilities meet the requirements of STCW convention and other expanded applications, collaborated research and coordination are needed in development and application of shiphandling simulators. Performance standard should be established for shiphandling simulator systems considering the advanced research needs as well as the needs in education, training, and assessment of competence. Standardizing and exchanging shiphandling mathematical models will improve critical performance of the system. Cooperated research on model course and training assessment approaches will enhance the training standard. In addition, the rapid spread of the internet technology has shown a promising future of application of shiphandling simulators through internet. Research has been carried out on internet based integration of multiple shiphandling simulators. A multi-agent based system, including necessary hardware, has been developed. Collaborated operation of the system can be of benefit in filling the gaps of the technical and operational level and methodology between maritime universities, enhancing mutual understanding of the navigation customs and culture background among cadets and seafarers from different countries, facilitating communication and maritime English training, and extending the functions of shiphandling simulators.

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Reliability Evaluation Model for Digital Rights Management Software (디지털 저작권 관리 소프트웨어의 신뢰성 평가 모델)

  • Yang, Hae-Sool;Kang, Sang-Won;Choi, Hyoung-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.8
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    • pp.1850-1859
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    • 2009
  • The quality evaluation of software reliability for digital rights management rating will lead and as the technique it will be able to induce the quality increase of digital copyright management software the strategic engineering development which accommodates an international standard there is a possibility which an objectivity and an application degree it will raise. In order to evaluate the reliability quality of digital copyright management software from the research which it sees it proposed the tentative metric, it measured the result according to the standard which is appropriate it accomplished it presented it presented a quality and a research in about the method which it decides and an evaluation instance and a evaluation method clearly. The research which it sees it leads and it induces that there is a possibility of being sufficient it sees the reliability quality increase of digital copyright management software and the demand which is quantitative/qualitative in about digital copyright management software.

A Study on Information Systematization of Detail Drawings for Connectivity between BIM Libraries and Technical Contents based on Information Framework (BIM 라이브러리-기술콘텐츠 연계를 위한 정보프레임워크 기반의 정보 체계화 연구-부분상세를 중심으로)

  • Jo, Chan-Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.10
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    • pp.54-60
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    • 2016
  • Building information modeling (BIM) has the advantage of having been utilized for various scenarios through a single model. Although extracting 2D drawings from BIM is one of the advantages, there are many difficulties when utilized in practical work. Architectural detail drawings are an important factor for expressing interior finishing materials and complicated construction methods, as well as for cost estimations. However, creating detail drawings does not have a standard, and each design company establishes its own detail drawings, so it is hard to share or exchange information in the construction industry. Therefore, this study suggests a systemized method for making detail drawings, and explains how it can be utilized as back data for quantity take-off and construction expenses linked with BIM libraries.

Halo Effect in Evaluating Government Funded Art Programs: The Case of Local Representative Performing Art Festivals (정부지원 공연예술행사 평가의 후광효과: 지역대표공연예술제 성과관리 체계를 중심으로)

  • Cho, Mun-Seok;Oh, Jae-Rok
    • Journal of Convergence for Information Technology
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    • v.9 no.8
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    • pp.123-133
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    • 2019
  • This research empirically investigated halo effect in evaluating culture and art performance program. We diagnosed halo effect by using correlation analysis, factor analysis, and regression model on results and scores of fifteen evaluation indicators within three categories for the 107 Local Representative Performance Art Festivals in 2014 and 2015. The results indicates strong possibility of halo effect in culture and art performance evaluation. The correlation coefficients between evaluation indicators is higher than 0.5 and factor structure does not match with evaluation categories in both years. Scores in categories and standard deviations also are also significantly correlated with each other. The results implies that more sophisticated standard, diversification of evaluator, education, and meta-anlysis are need to control halo effect.

Information Security Management System on Cloud Computing Service (클라우드 컴퓨팅 서비스에 관한 정보보호관리체계)

  • Shin, Kyoung-A;Lee, Sang-Jin
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.22 no.1
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    • pp.155-167
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    • 2012
  • Cloud computing service is a next generation IT service which has pay-per-use billing model and supports elastically provisioning IT infra according to user demand. However it has many potential threats originating from outsourcing/supporting service structure that customers 'outsource' their own data and provider 'supports' infra, platform, application services, the complexity of applied technology, resource sharing and compliance with a law, etc. In activation of Cloud service, we need objective assessment standard to ensure safety and reliability which is one of the biggest obstacles to adopt cloud service. So far information security management system has been used as a security standard for a security management and IT operation within an organization. As for Cloud computing service it needs new security management and assessment different from those of the existing in-house IT environment. In this paper, to make a Information Security Management System considering cloud characteristics key components from threat management system are drawn and all control domain of existing information security management system as a control components are included. Especially we designed service security management to support service usage in an on-line self service environment and service contract and business status.