• Title/Summary/Keyword: minimal model

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Evaluation of Water Retentive Pavement as Mitigation Strategy for Urban Heat Island Using Computational Fluid Dynamics

  • Cortes, Aiza;Shimadera, Hikari;Matsuo, Tomohito;Kondo, Akira
    • Asian Journal of Atmospheric Environment
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    • v.10 no.4
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    • pp.179-189
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    • 2016
  • Here we evaluated the effect of using water retentive pavement or WRP made from fly ash as material for main street in a real city block. We coupled computational fluid dynamics and pavement transport (CFD-PT) model to examine energy balance in the building canopies and ground surface. Two cases of 24 h unsteady analysis were simulated: case 1 where asphalt was used as the pavement material of all ground surfaces and case 2 where WRP was used as main street material. We aim to (1) predict diurnal variation in air temperature, wind speed, ground surface temperature and water content; and (2) compare ground surface energy fluxes. Using the coupled CFD-PT model it was proven that WRP as pavement material for main street can cause a decrease in ground surface temperature. The most significant decrease occurred at 1200 JST when solar radiation was most intense, surface temperature decreased by $13.8^{\circ}C$. This surface temperature decrease also led to cooling of air temperature at 1.5 m above street surface. During this time, air temperature in case 2 decreased by $0.28^{\circ}C$. As the radiation weakens from 1600 JST to 2000 JST, evaporative cooling had also been minimal. Shadow effect, higher albedo and lower thermal conductivity of WRP also contributed to surface temperature decrease. The cooling of ground surface eventually led to air temperature decrease. The degree of air temperature decrease was proportional to the surface temperature decrease. In terms of energy balance, WRP caused a maximum increase in latent heat flux by up to $255W/m^2$ and a decrease in sensible heat flux by up to $465W/m^2$.

Models for Privacy-preserving Data Publishing : A Survey (프라이버시 보호 데이터 배포를 위한 모델 조사)

  • Kim, Jongseon;Jung, Kijung;Lee, Hyukki;Kim, Soohyung;Kim, Jong Wook;Chung, Yon Dohn
    • Journal of KIISE
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    • v.44 no.2
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    • pp.195-207
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    • 2017
  • In recent years, data are actively exploited in various fields. Hence, there is a strong demand for sharing and publishing data. However, sensitive information regarding people can breach the privacy of an individual. To publish data while protecting an individual's privacy with minimal information distortion, the privacy- preserving data publishing(PPDP) has been explored. PPDP assumes various attacker models and has been developed according to privacy models which are principles to protect against privacy breaching attacks. In this paper, we first present the concept of privacy breaching attacks. Subsequently, we classify the privacy models according to the privacy breaching attacks. We further clarify the differences and requirements of each privacy model.

Structure-Based Virtual Screening and Biological Evaluation of Non-Azole Antifungal Agent

  • Lee, Joo-Youn;Nam, Ky-Youb;Min, Yong-Ki;Park, Chan-Koo;Lee, Hyun-Gul;Kim, Bum-Tae;No, Kyoung-Tai
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2005.09a
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    • pp.139-143
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    • 2005
  • Cytochrome P450 14${\alpha}$-sterol demethylase enzyme (CYP51) is the target a of azole type antifungals. The azole blocks the ergosterol synthesis and thereby inhibits fungal growth. A three-dimensional (3D) homology model of CYP51 from Candida albicans was constructed based on the X-ray crystal structure of CYP51 from Mycobacterium tuberculosis. Using this model, the binding modes for the substrate (24-methylene-24, 25-dihydrolanosterol) and the known inhibitors (fluconazole, voriconazole, oxiconazole, miconazole) were predicted from docking. Virtual screening was performed employing Structure Based Focusing (SBF). In this procedure, the pharmacophore models for database search were generated from the protein-ligands interactions each other. The initial structure-based virtual screening selected 15 compounds from a commercial available 3D database of approximately 50,000 molecule library, Being evaluated by a cell-based assay, 5 compounds were further identified as the potent inhibitors of Candida albicans CYP51 (CACYP51) with low minimal inhibitory concentration (MIC) range. BMD-09-01${\sim}$BMD-09-04 MIC range was 0.5 ${\mu}$g/ml and BMD-09-05 was 1 ${\mu}$g/ml. These new inhibitors provide a basis for some non-azole antifungal rational design of new, and more efficacious antifungal agents.

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Concrete Optimum Mixture Proportioning Based on a Database Using Convex Hulls (최소 볼록 집합을 이용한 데이터베이스 기반 콘크리트 최적 배합)

  • Lee, Bang-Yeon;Kim, Jae-Hong;Kim, Jin-Keun
    • Journal of the Korea Concrete Institute
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    • v.20 no.5
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    • pp.627-634
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    • 2008
  • This paper presents an optimum mixture design method for proportioning a concrete. In the proposed method, the search space is constrained as the domain defined by the minimal convex region of a database, instead of the available range of each component and the ratio composed of several components. The model for defining the search space which is expressed by the effective region is proposed. The effective region model evaluates whether a mix-proportion is effective on processing for optimization, yielding highly reliable results. Three concepts are adopted to realize the proposed methodology: A genetic algorithm for the optimization; an artificial neural network for predicting material properties; and a convex hull for evaluating the effective region. And then, it was applied to an optimization problem wherein the minimum cost should be obtained under a given strength requirement. Experimental test results show that the mix-proportion obtained from the proposed methodology using convex hulls is found to be more accurate and feasible than that obtained from a general optimum technique that does not consider this aspect.

3D Reconstruction and Self-calibration based on Binocular Stereo Vision (스테레오 영상을 이용한 자기보정 및 3차원 형상 구현)

  • Hou, Rongrong;Jeong, Kyung-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.9
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    • pp.3856-3863
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    • 2012
  • A 3D reconstruction technique from stereo images that requires minimal intervention from the user has been developed. The reconstruction problem consists of three steps of estimating specific geometry groups. The first step is estimating the epipolar geometry that exists between the stereo image pairs which includes feature matching in both images. The second is estimating the affine geometry, a process to find a special plane in the projective space by means of vanishing points. The third step, which includes camera self-calibration, is obtaining a metric geometry from which a 3D model of the scene could be obtained. The major advantage of this method is that the stereo images do not need to be calibrated for reconstruction. The results of camera calibration and reconstruction have shown the possibility of obtaining a 3D model directly from features in the images.

Dosimetric characteristics of an independent collimator system using measurements performed quarter fields. (Tungsten eyeball shield block의 임상적용에 관한 고찰)

  • Jeong, Deok-Yang;Lee, Byoung-Koo;Hwang, Woong-Koo
    • The Journal of Korean Society for Radiation Therapy
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    • v.14 no.1
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    • pp.89-94
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    • 2002
  • During radiation therapy with electron beam to eyelid, we must keep the minimal dose on eyeball as possible. especially in the treatment of Sebaceous gland carcinoma, Squamouse cell ca., and basal cell ca. of eyelid and low grade MALToma etc. But if radiation field covered the upper & lower eyelid, it makes a cataract on lens of treated eye, in late complications. Now we reports the advantages of Tungsten eyeball shielding block compare to previously used lead block. with BOLX-I material, we made a eyeball model and measured the absorbed dose of 6MeV & 9MeV electron hem at 6 point of eyeball model with TLD chip. And compare the absorbed dose to previously lead block and other types of Tungsten eyeball shielding block.

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Thermal Analysis of TRIO-CINEMA Mission

  • Yoo, Jae-Gun;Jin, Ho;Seon, Jong-Ho;Jeong, Yun-Hwang;Glaser, David;Lee, Dong-Hun;Lin, Robert P.
    • Journal of Astronomy and Space Sciences
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    • v.29 no.1
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    • pp.23-31
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    • 2012
  • Thermal analysis and control design are prerequisite essential to design the satellite. In the space environment, it makes satellite survive from extreme hot and cold conditions. In recent years CubeSat mission is developed for many kinds of purpose. Triplet Ionospheric Observatory (TRIO)-CubeSat for Ion, Neutral, Electron, MAgnetic fields (CINEMA) is required to weigh less than 3 kg and operate on minimal 3 W power. In this paper we describe the thermal analysis and control design for TRIO-CINEMA mission. For this thermal analysis, we made a thermal model of the CubeSat with finite element method and NX6.0 TMG software is used to simulate this analysis model. Based on this result, passive thermal control method has been applied to thermal design of CINEMA. In order to get the better conduction between solar panel and chassis, we choose aluminum 6061-T6 for the material property of standoff. We can increase the average temperature of top and bottom solar panels from $-70^{\circ}C$ to $-40^{\circ}C $ and decrease the average temperature of the magnetometer from $+93^{\circ}C$ to $-4^{\circ}C$ using black paint on the surface of the chassis, inside of top & bottom solar panels, and magnetometer.

Experimental Study on Particle Collection Efficiency of Axial-flow Cyclone in Air Handling Unit (공기조화기 장착용 축상유입식 싸이클론의 입자제거효율에 대한 실험적 연구)

  • Kim, Se-Young;Kwon, Soon-Bark;Park, Duck-Shin;Cho, Young-Min;Kim, Jin-Ho;Kim, Myung-Joon;Kim, Tae-Sung
    • Journal of Korean Society for Atmospheric Environment
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    • v.27 no.3
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    • pp.272-280
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    • 2011
  • A novel particle removal system for air handling unit (AHU) of subway station was evaluated experimentally. The novel system was designed in order to minimize the maintenance cost by applying axial-flow cyclones. The system consists of multiple cyclone units and dust trap. Based on our previous numerical study, it was found to be effective for removal $1\sim10{\mu}m$ sized dust particles. In this study, we manufactured the mock-up model and evaluated the model experimentally. Liquid and solid test particles were generated for evaluating collection efficiency of the system and the pressure drop was monitored. The collection efficiency was varied from 41.2% to 85.9% with increasing the sizes of particle from 1 to $6.5{\mu}m$ by particle count ratio of inlet and outlet. The pressure drop was maintained constant less than $20mmH_2O$. In addition, the collection efficiency was estimated by total mass for solid test particles. It was found that the collection efficiency was 65.7% by particle mass ratio of inlet and outlet. It shows that present system can replace current pre-filters used in subway HVAC system for removing particulate matters with minimal operational cost.

A Study on Information Security Departmentalization Model (정보보호 전담조직 편성모델에 관한 연구)

  • Kang, Hyunsik;Kim, Jungduk
    • The Journal of Society for e-Business Studies
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    • v.20 no.2
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    • pp.167-174
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    • 2015
  • Information security organization has normally been organized under the IT department. However, as the importance of information security has gradually increased, the way of information security organized for enterprise security management has become a noteworthy issue. The need for separation of Information security organization from IT department is growing, such as restriction on the concurrent positions in CIO and CISO. Nowadays there are many studies about Information security organization while relatively there has been minimal research regarding a departmentalization. For these reasons this study proposes a Information Security Departmentalization Model which is based on business risk and reliance on the IT for effectively organizing Information security organization, using Contingency theory. In addition, this study classified the position of Information security organization into Planning & Coordination, Internal Control, Management and IT and analyze the strengths and weaknesses of each case.

Detection of BLV Proviral DNA in Korean Native Goats Experimentally Infected with Bovine Leukemia Virus by Polymerase Chain Reaction (소백혈병 바이러스 (Bovine Leukemia Virus)에 감염된 한국 재래산양에서 PCR기법을 이용한 BLV 유전자 검출)

  • Jun, Moo-Hyung;Chang, Kyung-Soo;Cho, Young-Sung;Park, Jong-Hyeon;An, Soo-Hwan
    • The Journal of Korean Society of Virology
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    • v.27 no.2
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    • pp.217-225
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    • 1997
  • PCR amplication using the primers for gag, pol and env genes in BLV (bovine leukemia virus) proviral DNA and syncytium assay were carried out for the Korean native goats experimentally infected with bovine leukemia virus to investigate pathogenesis of BLV in the goats, and to establish a model animal for BLV infection. The oligonucleotide primers used in PCR revealed very high specificity. The minimal amount of FLK-BLV cellular chromosomal DNA to detect the integrated BLV proviral DNA was 10 ng. The peripheral blood lymphocytes from the goat infected with BLV were examined at regular intervals by PCR amplification and syncytium assay. Pol or gag genes were detected in none of three infected goats at the 1st week post-infection (p.i.). At the 4th week p.i., one of three goats showed the amplified gag gene. Thereafter detection rates for the genes were increased, indicating that the BLV proviral genes were integrated in all of the lymphocytes from three goats, at the 16th weeks p.i., when it was evident in syncytium assay that the lymphocytes from all of three goats were infested with infective BLV. Investigating the tissues from the necropsied goats at the 8th month p.i., the amplified BLV proviral genes and infective BLV were detected in all of the peripheral lymphocytes from three infected-goats. Among various tissues examined, the amplified BLV proviral genes were observed in spleen and superficial cervical, mandibular and retropharyngeal lymph nodes, and the infective BLV, in superficial cervical and mandibular lymph nodes. It was assumed that the Korean native goat was quite susceptible to BLV infection, indicating that the goat could be a good model animal for BLV.

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