• Title/Summary/Keyword: top-down

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DEVELOPMENT OF CONCRETE FILLED TUBE AS A PILLAR PILE FOR TOP DOWN METHOD

  • Jee-Yun Song;Hong-Chul Rhim;Seung-Weon Kim
    • International conference on construction engineering and project management
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    • 2009.05a
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    • pp.808-813
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    • 2009
  • Top-down method is widely used for urban area construction for its advantages in reducing environmental problems such as dust and noise, and saving construction cost depending on given conditions of a construction site. Because the excavation and construction of super- and sub-structures of the building have to be proceeded simultaneously, a column has to be embedded prior to excavation. This column is called a pillar column or pre-founded column. Usually a wide flange section is used for these columns. To place the columns, usually the diameter of casing holes needs to be larger than the section of the wide flange itself in order to accommodate a couple of tremie pipes for pouring concrete. In this paper, a newly developed method of using circular pipe as an alternative to the existing wide flange section is discussed. The crucial part of the new method is to develop a connection between the circular column and concrete flat slabs. For shear force transfer from concrete slab to the concrete filled tube (CFT) column, shear jackets with studs and shear bands are proposed. The studs are welded on the jackets at shop and placed around the circular column on site. The shear bands are welded on the outer side of the CFT at shop and inserted into ground with the CFT. Test results and application of the method to a construction site are also provided in this paper.

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A SIMULINK Modeling for a Fractional-N Frequency Synthesizer (SIMULINK를 이용한 Fractional-N 주파수합성기의 모델링 기법)

  • Kim, In-Jeong;Seo, Woo-Hyong;Ahn, Jin-Oh;Kim, Dae-Jeong
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.4
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    • pp.103-109
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    • 2007
  • This paper presents behavioral models using SIMULINK and Verilog-a for a PLL based fractional-N frequency synthesizer. By adopting a top-down approach along with the traditional bottom-up transistor level design in parallel, the design time is greatly shortened, and a co-verification method for both the digital and the analog part is considered. Under this consideration, the SIMULINK modeling reduces simulation time and easily estimates the PLL's performance on the top level. Verilog-a is able to verify the feasibility of each blocks at first hand because it is compatible with transister level circuits. Then, an efficient way of the design is presented by comparing the results of both models.

Efficient Global Placement Using Hierarchical Partitioning Technique and Relaxation Based Local Search (계층적 분할 기법과 완화된 국부 탐색 알고리즘을 이용한 효율적인 광역 배치)

  • Sung Young-Tae;Hur Sung-Woo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.12
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    • pp.61-70
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    • 2005
  • In this paper, we propose an efficient global placement algorithm which is an enhanced version of Hybrid Placer$^{[25]}$, a standard cell placement tool, which uses a middle-down approach. Combining techniques used in the well-known partitioner hMETIS and the RBLS(Relaxation Based Local Search) in Hybrid Placer improves the quality of global placements. Partitioning techniques of hMETIS is applied in a top-down manner and RBLS is used in each level of the top-down hierarchy to improve the global placement. The proposed new approach resolves the problem that Hybrid Placer seriously depends on initial placements and it speeds up without deteriorating the placement quality. Experimental results prove that solutions generated by the proposed method on the MCNC benchmarks are comparable to those by FengShui which is a well known placement tool. Compared to the results of the original Hybrid Placer, new method is 5 times faster on average and shows improvement on bigger circuits.

Ski-end shape control based on the model in heavy plate mill (후판 압연공정에서의 판 선단부 형상제어 연구)

  • Chun, M.S.;Park, H.D.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.10a
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    • pp.93-95
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    • 2007
  • Studies on ski-end shape control at the top end of rolling plate in heavy thick plate mill by using FEM analysis and measuring system have been performed. Plate shape behaviour at the top-end on rolling by the two different methods in finishing rolling process has been observed. One is to minimize the height of ski-end by using pass line based on the relational model between shape factor and pick-up and the other one is to prevent turn down problem caused by the impact between table roller and down bended plate on rolling by using roll speed difference. To minimize the height of ski-end, the prediction models based on the FEM analysis and measuring data was developed. The control method of ski - end shape on finishing rolling process was applied in actual mill and the height of ski-end was reduced by about 50% compared with conventional operation.

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A study on how to find new project of Six Sigma (식스 시그마 프로젝트 개발에 관한 연구)

  • Lim, Sung-Uk;Yoon, Seong-Pil;Kim, Chang-Soo
    • Journal of the Korea Safety Management & Science
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    • v.8 no.5
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    • pp.27-56
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    • 2006
  • Prior to Six Sigma, many companies had adopted a policy management method designed to manage business performances through the top-down deployment of management policies. This policy management method and the Six Sigma CTQ Flow Down will make a good combination when their merits are developed and systemized as the management innovation program which enables to set up innovation targets along with management targets in the stage of strategic planning and to participate all the personnel from top management down in achieving th targets. This paper will help the companies implementing Six Sigma improve their management constitutions and achieve better management performances through the integration of policy management and Six Sigma.

A Study on Methodology of U-City Promotion(Top-Down vs Bottom-Up Approach Model) (U-City 추진방법론에 대한 고찰(Top Down vs Bottom Up 모델))

  • Lee, Sang-Hun;Kim, Hyong-Bok
    • Spatial Information Research
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    • v.17 no.1
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    • pp.131-144
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    • 2009
  • Recently, a lot of local autonomous entities are promoting Ubiquitous City(U-City) Construction by integrating Information Communication Technology(ICT) with city development, and also internationally, a lot of cities are making efforts to develop U-City to intensify a city's competitive strength and improve life quality of city dwellers. In keeping with such a stream of the times, each local autonomous entity and project developer are developing a lot of methodologies to establish optimal U-City in corresponding cities and also inquiring into a variety of development procedures, such as connecting existing urban development methods with information establishment methods. The method used usually is to establish Information strategy Plan(ISP) for a city which will be developed through consulting in the stage of city development planning. ISP is to establish vision & strategy for building the ubiquitous city and is a methodology including city vision, strategy, goal, and implementation method, etc. However, due to a lot of variables, such as a variety of city environment, establishment period, budget, information technology, and etc., it is difficult to contain establishment plans for every occasion in a similar method, in reality. Therefore, it is naturally necessary to suggest plans for city vision & strategy, and selection of element technology/service. Thus, this paper suggests models for vision & strategy establishment of U-City and suggests Top-Down Approach and Bottom-Up Approach method as a plan for U-City establishment. In addition, this paper analyzes general promotion methodologies for constructing U-City and analyzes how these two strategic methods [Top-Down Approach and Bottom-Up Approach] for city vision establishment are composed in such a methodology, to define and analyze its constituent plan.

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Infliximab: The Benefit for Refractory Crohn Disease and Top-down Induction Therapy in Severe Crohn Disease (Infliximab: 불응성 크론병 치료법으로서의 유용성과 Top-down 관해 유도 요법으로서의 가능성)

  • Lee, Jee-Hyun;Lee, Hae-Jeong;Park, Sung-Eun;Choe, Yon-Ho
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.11 no.1
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    • pp.28-35
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    • 2008
  • Purpose: The aim of this study is to report the efficacy of infliximab, a monoclonal antibody directed against tumor necrosis factor alpha which is used for both treatment of refractory pediatric Crohn disease (CD) and induction of remission. Methods: Among pediatric patients who were diagnosed with CD at Samsung Medical Center between March 2001 and August 2007, a total of 16 patients were given infliximab to treat conventional therapyresistant refractory CD and severe active CD for induction of remission. Patients needing maintenance therapy were treated with an infliximab infusion every 8 weeks, and fistulizing CD patients occasionally received the infusion upon the condition that a fistula developed. The efficacy of treatment was assessed by comparing the Pediatric Crohn Disease Activity Index (PCDAI), Hct, ESR, CRP, and serum albumin levels using paired t-test. Results: The male/female ratio was 13:3, and the median age was 13 years (range, 21 months~15 years). The patients included 7 cases of therapy-resistant refractory CD, 7 cases of severe active CD, and 2 cases of fistulizing CD. Mean PCDAI before infliximab therapy was 34.19${\pm}$14.96, and mean follow-up PCDAI within 2 to 4 weeks after the last infusion was significantly lower, at 6.88${\pm}$10.31 (p=0.000). Hematological markers such as ESR (p=0.000), serum albumin (p=0.016), and CRP (p=0.009) also improved significantly after infusion. Remission was achieved in 2 of 4 patients refractory to conventional therapy. Among 3 steroid-dependent patients, 2 were able to discontinue steroid therapy, and dose reduction was possible in 1 patient. Remission after top-down therapy without prior use of other immunomodulators was achieved in 6 weeks in all 7 of the patients who had severe CD. Nine of ten refractory fistulizing CD patients also showed improvement after infliximab therapy. Conclusion: Infliximab was effective in pediatric refractory CD for induction of remission and maintenance therapy, as well as in severe CD for top-down induction therapy. Furthermore, infliximab has contributed to steroid cessation and dose reduction. Long-term follow-up evaluation is needed to determine safety and efficacy of infliximab in the future.

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Integrative Meta-Analysis of Multiple Gene Expression Profiles in Acquired Gemcitabine-Resistant Cancer Cell Lines to Identify Novel Therapeutic Biomarkers

  • Lee, Young Seok;Kim, Jin Ki;Ryu, Seoung Won;Bae, Se Jong;Kwon, Kang;Noh, Yun Hee;Kim, Sung Young
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.7
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    • pp.2793-2800
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    • 2015
  • In molecular-targeted cancer therapy, acquired resistance to gemcitabine is a major clinical problem that reduces its effectiveness, resulting in recurrence and metastasis of cancers. In spite of great efforts to reveal the overall mechanism of acquired gemcitabine resistance, no definitive genetic factors have been identified that are absolutely responsible for the resistance process. Therefore, we performed a cross-platform meta-analysis of three publically available microarray datasets for cancer cell lines with acquired gemcitabine resistance, using the R-based RankProd algorithm, and were able to identify a total of 158 differentially expressed genes (DEGs; 76 up- and 82 down-regulated) that are potentially involved in acquired resistance to gemcitabine. Indeed, the top 20 up- and down-regulated DEGs are largely associated with a common process of carcinogenesis in many cells. For the top 50 up- and down-regulated DEGs, we conducted integrated analyses of a gene regulatory network, a gene co-expression network, and a protein-protein interaction network. The identified DEGs were functionally enriched via Gene Ontology hierarchy and Kyoto Encyclopedia of Genes and Genomes pathway analyses. By systemic combinational analysis of the three molecular networks, we could condense the total number of DEGs to final seven genes. Notably, GJA1, LEF1, and CCND2 were contained within the lists of the top 20 up- or down-regulated DEGs. Our study represents a comprehensive overview of the gene expression patterns associated with acquired gemcitabine resistance and theoretical support for further clinical therapeutic studies.