• 제목/요약/키워드: direct differentiation

검색결과 289건 처리시간 0.024초

다물체 시스템의 민감도 해석 (DESIGN SENSITIVITY ANALYSIS FOR MULTIBODY SYSTEMS)

  • Lee, Jong-Nyun;Park, Soo-Hong
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.378-382
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    • 1996
  • This paper presents a 'mixed' method for performing the sensitivity analysis for multibody dynamics. The mixed method uses both the analytical derivation and the numerical evaluation, in which premitive derivations rely on the analytical process and their associated individual terms are evaluated by the numerical precess. Therefore, this method can eliminate difficulty in dervation of the direct differentiation. Furthermore, by using the joint coordinate formulation for the equations of motion, compulational efficiencyand numerical accuracy are achieved.

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철도차량의 설계 민감도 해석을 위한 효율적인 알고리즘 개발 (An Efficient Algorithm for Design Sensitivity Analysis of railway Vehicle Systems)

  • 배대성;조희제;백성호;이관섭;조연옥
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 1998년도 창립기념 춘계학술대회 논문집
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    • pp.299-306
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    • 1998
  • Design sensitivity analysis of a mechanical system is an essential tool for design optimization and trade-off studies. This paper presents an efficient algorithm for the design sensitivity analysis of railway vehicle systems, using the direct differentiation method. The cartesian coordinate is employed as the generalized coordinate. The governing equations of the design sensitivity analysis are formulated as the differential equations. Design sensitivity analysis of railway vehicle systems is performed to show the validity and efficiency of the proposed method.

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A Value-based Real Time Pricing Under Imperfect Information on Consumer Behavior

  • Kim, Balho H.;Park, Jong-Bae
    • 에너지공학
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    • 제8권4호
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    • pp.505-511
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    • 1999
  • One of the major challenges confronting a multiservice electric utility is the establishment of the right prices, for its services. The key objectives of particular pricing schemes are reasonableness of company earnings. Economic efficiency, the responsiveness of supply and of the allocation of sources to the desires of consumers, and maintenance of some degree of competition. This paper proposes a value-based pricing mechanism amenable to the current deregulation situation in electricity market allowing service differentiation. The proposed pricing mechanism can be implemented ina nodal auction model, and can also be applied to direct load control.

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수압을 받는 원통형 쉘의 최적설계 (Optimum Design of the Cylindrical Shell under External Pressuer Loading)

  • 임오강;이병우;전완수;정현기
    • 전산구조공학
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    • 제8권1호
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    • pp.85-94
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    • 1995
  • 수압을 받는 원통형 쉘의 몸체설계는 구조물에 외압이 작용할 때 발생하는 최대 응력과 변형 및 좌굴을 해석하여, 주어진 한계를 견딜 수 있는 쉘의 두께를 구해야 한다. 중앙 평형부 몸체의 두께를 설계변수로 선정하여 형상 최적화법으로서 원통형 쉘의 치수를 설계하는 방법을 제안하였다. 민감도 해석은 직접 미분법을 사용하여 유도하였으며, 비선형 계획법으로 최대 응력과 변형 및 좌굴 제한식 등을 만족하는 최적설계를 수행하였다.

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Comparison of Reprogramming Methods for Generation of Induced-Oligodendrocyte Precursor Cells

  • Lee, Eun-Hye;Park, Chang-Hwan
    • Biomolecules & Therapeutics
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    • 제25권4호
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    • pp.362-366
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    • 2017
  • Direct conversion by trans-differentiation is of growing interest in cell therapy for incurable diseases. The efficiency of cell reprogramming and functionality of converted cells are important considerations in cell transplantation therapy. Here, we compared two representative protocols for the generation of induced-oligodendrocyte progenitor cells (iOPCs) from mouse and rat fibroblasts. Then, we showed that induction of Nkx6.2, Olig2, and Sox10 (NOS) was more effective in mouse fibroblasts and that induction of Olig2, Sox10, and Zfp536 (OSZ) was more effective at reprogramming iOPCs from rat fibroblasts. However, OSZ-iOPCs did not show greater proliferation than NOS-induced cells. Because the efficiency of iOPCs generation appears to differ between cell species depending on transcription factors and culture conditions, it is important to select appropriate methods for efficient reprogramming.

A Configuration Design Sensitivity Analysis for Kinematically driven Mechanical Systems

  • Kim, D.W.;Yang, S.M.;Kim, H.W.;Bae, D.S.
    • 한국생산제조학회지
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    • 제7권3호
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    • pp.110-117
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    • 1998
  • A continuum-based configuration design sensitivity analysis method is developed for kinematically driven mechanical systems. The configuration design variable for mechanical systems is defined. The 3-1-3 Euler angle is employed as the orientation design variable. Kinematic admissibility conditions of configuration design change. Direct differentiation method is used to derive the governing equations of the design sensitivity. Numerical examples are presented to demonstrate the validity and effectiveness of the proposed method.

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Evidence for Direct Inhibition of MHC-Restricted Antigen Processing by Dexamethasone

  • Im, Sun-A;Gerelchuluun, Turmunkh;Lee, Chong-Kil
    • IMMUNE NETWORK
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    • 제14권6호
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    • pp.328-332
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    • 2014
  • Dexamethasone (Dex) was shown to inhibit the differentiation, maturation, and antigen-presenting function of dendritic cells (DC) when added during DC generation or maturation stages. Here, we examined the direct effects of Dex on MHC-restricted antigen processing. Macrophages were incubated with microencapsulated ovalbumin (OVA) in the presence of different concentrations of Dex for 2 h, and the efficacy of OVA peptide presentation was evaluated using OVA-specific CD8 and CD4 T cells. Dex inhibited both class I- and class II-restricted presentation of OVA to T cells; this inhibitory effect on antigen presentation was much more potent in immature macrophages than in mature macrophages. The presentation of the exogenously added OVA peptide SIINFEKL was not blocked by Dex. In addition, short-term treatment of macrophages with Dex had no discernible effects on the phagocytic activity, total expression levels of MHC molecules or co-stimulatory molecules. These results demonstrate that Dex inhibits intracellular processing events of phagocytosed antigens in macrophages.

농촌마을축제의 농산물 직거래 장터 디자인에 대한 사용자 평가 - 유니버설디자인 관점에서 - (User Evaluation of the Farmers' Market Design in the Rural Village Festival - The Perspective of the Universal Design -)

  • 채혜성;서애은
    • 농촌계획
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    • 제22권4호
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    • pp.49-60
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    • 2016
  • This study is in order to promote agricultural products sold in the rural village festivals direct transaction marketplace and enabled by a comprehensive user evaluation of the rural village festivals direct transaction marketplaces in universal design perspective, provide a design plan for your care and comfort of a rural village festival Direct Deals Marketplace there is a purpose. Thus, redefining the principles of universal design suitable for direct transactions rural village festival marketplaces, and to do this by reclassifying the design elements of the farmstand-type in a framework was developed 30 questions to evaluate items for Universal Design Evaluation. And, the selection of three villages along the rural village festivals scale and conducted a survey of Universal Design Rating. As a result, the overall assessment was positive for B villages of rural village festival marketplaces direct transactions, there was a significant difference with the other village. In particular, there was a notable difference in the fairness, efficiency, promotional, safety and hygiene. And, there was a significant difference in design elements for directing atmosphere by selling space, product display, hygiene. This paper presents the design suggestions about a rural village festivals farmers' market aspects of universal design for improvement of the marketplace as following, 1) placement for differentiation the markerplace and around sites in the festival place, 2) to build the operating systems of sustainable management for arrangement and organization during the festival, 3) to install the device for maintaining agricultural products freshness 4) to separate the sale of local specialty products and general food products, and 5) to locate the suitable space considering the visitors tour route in the festival place for large-scale festival.

Identification of Egr1 Direct Target Genes in the Uterus by In Silico Analyses with Expression Profiles from mRNA Microarray Data

  • Seo, Bong-Jong;Son, Ji Won;Kim, Hye-Ryun;Hong, Seok-Ho;Song, Haengseok
    • 한국발생생물학회지:발생과생식
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    • 제18권1호
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    • pp.1-11
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    • 2014
  • Early growth response 1 (Egr1) is a zinc-finger transcription factor to direct second-wave gene expression leading to cell growth, differentiation and/or apoptosis. While it is well-known that Egr1 controls transcription of an array of targets in various cell types, downstream target gene(s) whose transcription is regulated by Egr1 in the uterus has not been identified yet. Thus, we have tried to identify a list of potential target genes of Egr1 in the uterus by performing multi-step in silico promoter analyses. Analyses of mRNA microarray data provided a cohort of genes (102 genes) which were differentially expressed (DEGs) in the uterus between Egr1(+/+) and Egr1(-/-) mice. In mice, the frequency of putative EGR1 binding sites (EBS) in the promoter of DEGs is significantly higher than that of randomly selected non-DEGs, although it is not correlated with expression levels of DEGs. Furthermore, EBS are considerably enriched within -500 bp of DEG's promoters. Comparative analyses for EBS of DEGs with the promoters of other species provided power to distinguish DEGs with higher probability as EGR1 direct target genes. Eleven EBS in the promoters of 9 genes among analyzed DEGs are conserved between various species including human. In conclusion, this study provides evidence that analyses of mRNA expression profiles followed by two-step in silico analyses could provide a list of putative Egr1 direct target genes in the uterus where any known direct target genes are yet reported for further functional studies.

형질전환 체세포로부터 소 복제수정란의 효율적인 생산 (Efficient Production of Cloned Bovine Embryos from Transformed Somatic Cells)

  • Wee G.;B. H Sohn;Park, J. S.;D. B. Koo;Lee, K. K.;Y. M. Han
    • 한국가축번식학회지
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    • 제27권1호
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    • pp.25-34
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    • 2003
  • 인체 트롬보포이에틴(hTPO)은 megakaryopoiesis 과정에 주요한 역할을 하는 사이토카인이다. 따라서 이러한 트롬보포이에틴을 유선조직에서 직접적으로 발현시키기 위하여 소 베타 카제인 프로모터, 인체 트롬보포이에틴 cDNA 및 네오유전자로 구성된 발현벡터를 구축하였다. 소 귀조직 세포로부터 유도된 섬유아세포에 lipoffctamine을 이용하여 발현벡터(pBT-L n대)의 삽입을 유도하였다. G4l8 저항성을 지닌 세포의 콜로니 형성을 유도하기 위하여 2주 이상 배양을 실시하였다. 형질전환 콜로니는 PCR에 의해 동정하였으며, 이들 콜로니를 핵치환 전까지 계속적으로 증식을 유도하였다. 형질전환 세포에 의해 재구성된 난자는 전기적인 융합과 calcium ionophore와 6-DMAP를 이용한 활성화를 실시하였으며, 체외에서 7일간 배양을 실시하였다. 총 35개의 콜로니를 PCR에 의해 분석한 결과, 이 중 29(82.9%)개가 형질전환된 콜로니였다. 형질전환된 세포로 재구성된 난자의 난할율 및 배반포로의 발달율은 65.1%와 23.8%로 나타났다. 형질전환된 세포로 재구성된 난자로부터 발달한 29개의 배반포 중 27개가 형질전환으로 확인되었다. 따라서 이러한 결과들은 형질전환 소 수정란을 형질전환된 세포를 이용한 체세포 복제 기법을 통해 효과적으로 생산할 수 있다는 것을 제시하고있다.