• 제목/요약/키워드: CaaS

검색결과 59건 처리시간 0.03초

Cross-Correlation 해석을 통한 공동의 소음 특성 연구 (Study on Noise Characteristic of Open Cavity with Cross-Correlation Analysis)

  • 허대녕;김재욱;이덕주
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2002년도 학술대회지
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    • pp.755-758
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    • 2002
  • The physical phenomena of rectangular open cavity are numerically investigated in this paper Two-dimensional cavity problems with laminar boundary layers in upstream are simulated by using the compressible Wavier-Stokes equations. The high-order and high-resolution numerical schemes are used for the evaluation of spatial derivatives and the time integration. Cross-correlation is used to analyze the characteristics of wave propagation along time and spatial. Sudden phase shifting of 90 degrees is appeared near downstream edge, and this is coincident with the phase lag suggested in original Rossiter's equation. The results give a further understanding of the physical phenomenon of noise generation, and the resonance of flow and acoustic in cavity. Moreover, modified Rossiter's equation, which is more accurate and can be applied in various conditions, is suggested. The distance from the point of vortex generation to the point of vortex collapsing acts as effective distance of cavity resonance, and the phase difference between the point of vortex collapsing and the point of acoustic source acts as phase lag. The mechanism of acoustic generation is fully understood in this paper. The mechanism of acoustic generation is fully understood in this paper.

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Grp78/BiP과 Grp94의 생화학적 분석 (Biochemical Characterization of Glucose-Regulated Proteins, Grp94 and Grp78/BiP)

  • 강호성;김정락
    • 한국동물학회지
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    • 제38권2호
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    • pp.167-176
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    • 1995
  • Glucose-regulated proteins (grp's), srp94 3nd grp78/BiP, are a group of stress proteins which are highly synthesized in cells exposed to a variety of stressful agents including tunicamycin 3nd Ca2+ ionophore. Grp78/BiP is hon to function as a molecular chaperone which regulates the folding and assembly of secretory or membrane proteins, but the biological function of grp941 remains to be elucidated. In this study, we have examined the intracellular distribution of grV's and the function of srp94. Grp's are resident in the endoplasmic reticulum (ERI 3nd a specific sequence (Lys-Asp-Glu-Leu) at their C-terminus is known to be responsible for their retention within the ER. However, it has been unclear whether upon disturbance of cellular Caa+ homeostasis by the Ca2+ ionophore, grp94 is retained within the ER or secreted into the medium. In this study, we showed that in the presence of C3a+ ionophore, grp94 and gif78/BiP are present in the cells, mainly within the ER. We have also investigated whether grp94 might function as a molecular chaperone. Here we showed that in the immunoglobulin (Ig)-secreting hvbridom3 cells, grp94 transientlY interacts with fully glycosylated Is heavy chain, suggesting that grpg94 may be involved in facilitating the folding and assembly of Ig heavy chains.

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Unresolved Issues in Patent Dispute Evidence in Australia: Considering Arbitration as an Alternative to Litigation

  • Kwak, Choong Mok
    • 한국중재학회지:중재연구
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    • 제26권3호
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    • pp.121-147
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    • 2016
  • Factual issues in most patent litigation are related to very complicated techniques. Thus, the courts has emphasised that the technology in dispute has to be read and understood through the eyes of a person to whom it is directed. Therefore, among the various processes in federal litigation, most litigation in the field of patent infringement relies on at least some expert evidence. This paper focuses on issues regarding patent dispute evidence, and explore whether there are unresolved issues in evidential rules and procedures of patent proceedings. Further, this paper seeks to demonstrate that both the parties and the courts in patent disputes generally benefit from the current evidence system. However, in a number of Australian cases, the scope of expert evidence in patent cases has been strictly limited. Australian Government identified uncertain issues associated with the present patent enforcement system, due to factors such as a low level of knowledge about what patent rights entail, the high degree of uncertainty of outcome in legal proceedings, etc. Arbitration shall be reviewed and suggested as an alternative to tackling the ongoing problems in the trial system.

국내외 항공 안전계획 및 안전성과지표 동향 및 사례분석 (A Study on Aviation Safety Plan and Safety Performance Indicator of the Domestic and International Case Studies)

  • 이지선;이동훈;윤윤진
    • 대한교통학회지
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    • 제32권5호
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    • pp.431-440
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    • 2014
  • ICAO에서 제시한 국가항공프로그램(State Safety Program, SSP)에 따르면, 국가의 항공안전 목표 달성을 위해 안전성과 측정 및 평가에 활용되는 안전성과지표(SPI)의 설정과 관리가 필수적이다. 이에 따라, 세계 여러 국가들은 자국의 실정에 맞는 SPI 수립을 연구개발하고 있다. 그에 반해, 우리나라는 2008년 국가항공안전프로그램이 제정된 이후로 지금까지 동일한 지표를 사용해왔으며, SPI 수립체계에 대한 체계적인 정책 사업 및 관련 연구가 미비한 실정이다. 따라서, 본 연구는 국내 SPI체계 개발의 일환으로 항공선진국인 유럽과 미국의 SPI 개발계획에 대한 동향 조사를 하고자 한다. 이를 위해 EU의 유럽항공안전국 (EASA), 영국의 민간항공국 (CAA), 핀란드의 교통안전국(FTSA) 및 미국의 연방항공청 (FAA) 사례를 분석했다. 도출 결과를 기반으로 국내외 SPI 개발계획 및 수립체계의 차이점을 밝혔다. 본 연구를 통하여 도출된 분석 결과들은 향후 국내 SPI 수립체계의 발전방향 제시하기 위한 기틀을 마련할 수 있을 것이다.

Synthesis and Characterization of Cationic and Anionic Cyclodextrin Oligomers and Their Use in Layer-by-Layer Film Formation

  • Yang, Sung Yun;Hoonor, Rekha;Jin, Hye-Seung;Kim, Jeongkwon
    • Bulletin of the Korean Chemical Society
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    • 제34권7호
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    • pp.2016-2022
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    • 2013
  • Ionically modified ${\beta}$-cyclodextrins, which have excellent water-solubility, have been interested in purification technology as well as drug carrier system. The present study summarizes the synthesis and characterization of cationic and anionic ${\beta}$-cyclodextrin (${\beta}$-CyD) products using by polycondensation. The oligo (${\beta}$-CyD)s are synthesized from ${\beta}$-CyD, epichlorohydrin (EP) and choline chloride (CC; for cationic polymer) or chloroacetic acid (CAA; for anionic polymer) through one step polycondenstaion process. Unlike the previous studies, we successfully purified the ionic ${\beta}$-CyD condensation products from the ${\beta}$-CyD reaction mixtures and accomplished a great level of structural analysis. The detailed structural analysis of these ionic ${\beta}$-CyD compounds is done by $^1H$ NMR, MALDI-TOF as well as GPC analysis and confirms the formation of oligomers with a few units of ${\beta}$-CyD. We found that the sequence of reactant addition also could effect on the molecular weight of the resulting product as well as the molar ratio of the reactants. Finally, we used the cationic and anionic ${\beta}$-CyD oligomers for fabricating multilayer films by layer-layer process.

덕트가 있는 축류홴의 유동 및 음향장 해석 (An Analysis of the Flow and Sound Field of a Ducted Axial Fan)

  • 전완호;정기훈;이덕주
    • 한국유체기계학회 논문집
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    • 제3권2호
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    • pp.15-23
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    • 2000
  • The present work describes the prediction method for the unsteady flow field and the acoustic pressure field of a ducted axial fan. The prediction method is comprised of time-marching free-wake method, acoustic analogy, and the Kirchhoff-Helmholtz BEM. The predicted sound signal of a rotor is similar to the experiment one. We assume that the rotor rotates with a constant angular velocity and the flow field around the rotor is incompressible and inviscid. Then, a time-marching free-wake method is used to model the fan and to calculate the flow field. The force of each element on the blade is calculated by the unsteady Bernoulli equation. Lowson's method is used to predict the acoustic source. The newly developed Helmholtz-Kirchhoff BEM lot thin body is used to calculate tile sound field of the ducted fan. The ducted fan with 6 blades is analysed and the sound field around the duct is calculated.

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공동 주위에서의 압력 변화에 대한 연구 (Study on Pressure Variation around an Open Cavity)

  • 허대녕;이덕주
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.843-846
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    • 2004
  • Cavity tone is generated due to the feedback between flow and acoustic wave. It is recognized that the period is determined by the time required for the flow convection in one direction, the time required for the acoustic propagation in the other direction and the time for phase shift depending on the flows and mode. Most of the phenomena have been investigated by experiments and a simple but fundamental theory. But the cause of the phase shift and the correctness of the theory have not been clearly explained so far. In this paper, the phenomena are calculated numerically to obtain detail information of flow and acoustic wave to explain the mechanism including the phase. High order high resolution scheme of optimized high order compact is used to resolve the small acoustic quantities and large flow quantities at the same time. The data are reduced using cross correlation function in space and time and cross spectral density function which has phase information. Abrupt change in pressure near corner in cavity is observed and is relate to phase variation. The time required for the feedback between the flow and acoustic wave is calculated after the numerical simulation f3r various modes. The periods based on the time calculated using the above method and direct observation from the acoustic waves generated and propagated in the numerical simulation are compared. It is found that no phase shift is required if we examine the time required carefully. Rossiter's formula for the cavity tone used for quick estimation needs to be modified far some modes.

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Isolation and Characterization of Calmodulin 2 (CICAM2) Gene from Codonopsis lanceolata

  • Lee, Kang;In, Jun-Gyo;Yu, Chang-Yeon;Min, Byung-Hoon;Chung, Ill-Min;Kim, Se-Young;Kim, Yeong-Chae;Yang, Deok-Chun
    • Plant Resources
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    • 제7권3호
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    • pp.174-180
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    • 2004
  • Calmodulin, a $Ca^{2+}$-binding protein, has no enzyme activity. It combines with $Ca^{2+}$ and makes variable proteins to an active form. Calmodulin 2 is a ubiquitous protein in plants. To investigate the defense mechanism against various stresses, a clone encoding a calmodulin 2 protein was isolated from a cDNA library prepared from taproot mRNAs of Codonopsis lanceolata. The cDNA, designated CICAM2, is 719 nucleotides long and has an open reading frame of 450 bp with a deduced amino acid sequence of 149 residues. The deduced amino acid sequence of CICAM2 showed a high similarity with calmodulins of P. x hybrida (P27163) 97%, N. tabacum (BAB61908) 97%, S. tuberosum (AAA74405) 96%, Z. mays (CAA74307) 92%, C. richardii (AF510075) 93%, M. truncatula (AAM81203) 91%, and G. max (P62163) 91%. The transcriptional expression of the CICAM2 gene, was gradually increased by the CaCl$_2$ treatment. Whereas its expression And it was gradually decreased in the cold stress treatment.ent.

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초박형 노트북 냉각 터보팬의 유동 및 소음 분석 (Anallysis of the flow and noise characteristics of small turbo fan in a ultra slim note PC)

  • 전완호;임태균;미노리카와 가쿠;미야하라 마사하루
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2013년도 추계학술대회 논문집
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    • pp.775-780
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    • 2013
  • In recent years, a notebook like an ultrabook gets thinner. Its thickness causes problems in cooling fan performance, system installation condition, and so on. In this study, we installed a small turbofan in notebook system with very narrow gap in order to generate similar condition to a real product. Experiments were performed to measure the fan's performance and the flow and noise characteristics, its results were compared with computational ones. Prediction of P-Q curve using CFD showed under about 5% error in high flow rate and its trend was agreed with experimental one over the flow field. Experimental data to measure the noise at a distance of 100 mm from a rotation axis direction of an impeller corresponded well with computational ones of broadband and BPF noise. The noise experiments to measure at a distance of 100 mm from a rotation axis direction of an impeller corresponded well with computational ones of broadband and BPF noise. Especially, tip part of impeller blade and part of exit and bottom near in an analysis by a commercial program(FlowNoise).

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한국 전통 평직물의 실과 조직의 특징에 관한 연구 - 상고시대부터 조선시대까지를 중심으로 - (The study on the yarn & weaving characteristics of Korean traditional plain weave - Focused from the Sang-go(上古) period to the Joseon Dynasty(朝鮮王朝) -)

  • 최승연
    • 복식문화연구
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    • 제21권1호
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    • pp.1-16
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    • 2013
  • This study analyzed the characteristics of Korean traditional plain weave excavated from Sang-go period to Joseon Dynasty. To do this, this study classified the Korean traditional plain weave into fiber types(cotton, hemp & ramie, plain weaved silk), analyzed and compared the thickness, twist type of yarns and density by times. First, in characteristics of cotton, the average and maximum density of Joseon Dynasty were higher than those of Goryeo, twist type was mainly s-twist and the density of warp was higher than that of weft. Second, the maximum density of hemp & ramie was found in era of Three Kingdoms of Korea. In common characteristics of hemp & ramie, twist type was mainly s-twist(sometimes non-twist) to the Three Kingdoms of Korea and was changed into non-twist from the Goryeo. The density of warp was higher than that of weft in common. Generally, the average density of ramie was higher than that of hemp. Third, in the characteristics of plain weaved silk, twist type was mainly non-twist(sometimes s and z-twist) from Sang-go period to Joseon Dynasty. Warp-faced ribbed tabby was excavated in Goryeo, the average density of warp-faced ribbed tabby was higher than that of other fiber types plain weave. Generally, in all fiber types, the density of warp was higher than that of weft.