• Title/Summary/Keyword: Internal Partition

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Variation in wind load and flow of a low-rise building during progressive damage scenario

  • Elshaer, Ahmed;Bitsuamlak, Girma;Abdallah, Hadil
    • Wind and Structures
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    • v.28 no.6
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    • pp.389-404
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    • 2019
  • In coastal regions, it is common to witness significant damages on low-rise buildings caused by hurricanes and other extreme wind events. These damages start at high pressure zones or weak building components, and then cascade to other building parts. The state-of-the-art in experimental and numerical aerodynamic load evaluation is to assume buildings with intact envelopes where wind acts only on the external walls and correct for internal pressure through separate aerodynamic studies. This approach fails to explain the effect of openings on (i) the external pressure, (ii) internal partition walls; and (iii) the load sharing between internal and external walls. During extreme events, non-structural components (e.g., windows, doors or rooftiles) could fail allowing the wind flow to enter the building, which can subject the internal walls to lateral loads that potentially can exceed their load capacities. Internal walls are typically designed for lower capacities compared to external walls. In the present work, an anticipated damage development scenario is modelled for a four-story building with a stepped gable roof. LES is used to examine the change in the internal and external wind flows for different level of assumed damages (starting from an intact building up to a case with failure in most windows and doors are observed). This study demonstrates that damages in non-structural components can increase the wind risk on the structural elements due to changes in the loading patterns. It also highlights the load sharing mechanisms in low rise buildings.

Growth Inhibitory and Quinone Reductase Activity Stimulating Effects of Internal Organs of Todarodes pacificus Fractions on Human Cancer Cell Lines In vitro (오징어내장 분획물의 in vitro에서의 암세포 성장억제 및 quinone reductase유도 활성 증가 효과)

  • Shin, Mi-Ok;Bae, Song-Ja
    • Journal of Life Science
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    • v.19 no.9
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    • pp.1251-1257
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    • 2009
  • We investigated the growth inhibitory effect of internal organs of Todarodes pacificus (TP) on proliferation in human cancer cell lines in vitro. The internal organs of TP were extracted with methanol (TPM), which was then further fractionated into four subfractions by using a solvent partition method, resulting in hexane (TPMH), methanol (TPMM), butanol (TPMB), and aqueous (TPMA) soluble fractions. We determined the cytotoxic effect of these four fractions in three kinds of cancer cell lines - HepG2, MCF-7 and HT-29 - by MTT assay. Among the four subfractions of TPM, TPMH showed the strongest cytotoxic effects at a concentration of $300{\mu}g$/ml, displaying 91.56% on the HepG2 cell line and 85.93% on the MCF-7 cell line. Morphological changes such as membrane shirinking and blebbing of cells were also observed during TPMH treatment of HepG2 cells. In addition, we also observed quinone reductase (QR) induced effect in the methanol (TPMM) layer of HepG2 cells. TPMM showed the highest induction activity of quinone reductase on HepG2 cells among the other partition layers. The QR induced effect of TPMM was determined to be 2.7 at a level of $360{\mu}g$/ml with a control value of 1.0. Although further studies are needed, the present work suggests that internal organs of Todarodes pacificus (TP) may be a chemopreventive agent for the treatment of human cells.

Growth Inhibitory and Quinone Reductase Activity Stimulating Effects of Internal Organs of Aplysia kurodai Fractions on Cancer Cell Lines In vitro (군소내장 분획물의 in vitro에서의 암세포 성장억제 및 quinone reductase 유도 활성 증가 효과)

  • Shin, Mi-Ok
    • Journal of Life Science
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    • v.20 no.6
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    • pp.877-884
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    • 2010
  • We investigated the growth inhibitory effect of internal organs of Aplysia kurodai (AK) on proliferation in cancer cell lines in vitro. The internal organs of AK were extracted with methanol (AKM), which were then further fractionated into four subfractions by using solvent partition method, resulting in hexane (AKMH), methanol (AKMM), butanol (AKMB), and aqueous (AKMA) soluble fractions. We determined the cytotoxic effect of these four fractions in four kinds of cancer cell lines - HepG2, MCF-7, HT29 and B16-F10 - by MTT assay. Among the four subfractions of AKM, AKMM showed the strongest cytotoxic effects on all cancer cell lines which were used. Morphological changes such as membrane shrinking and blebbing of cells were also observed in AKMM treatment in HepG2 cells. In addition, we also observed quinone reductase (QR) induced effect in the methanol layer (AKMM) of HepG2 cells. AKMM showed the highest induction activity of quinone reductase on HepG2 cells among the partition layers. The QR induced effect of AKMM was determined to be 2.4 at $100\;{\mu}g/ml$ level with a control value of 1.0. Although further studies are needed, the present work suggests that internal organs of Aplysia kurodai (AK) may be a chemopreventive agent for the treatment of human cells.

Effect of Heat/Mass Transfer in the turbine blade internal passage with various rib arrangement (회전하는 터빈 블레이드 이차유로내 요철 배열이 열/물질전달에 미치는 영향)

  • Lee, Sei-Young;Cho, Hyung-Hee
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.22-29
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    • 2001
  • The present study investigates the effects of various rib arrangements and rotating on heat/mass transfer in the cooling passage of gas turbine blades. The cooling passage has very complex flow structure, because of the rib turbulator and rotating effect. Experiments and numerical calculation are conducted to investigate the complex flow structures and heat transfer characteristics; the numerical computation is performed using a commercial code, FLUENT ver.5, to calculate the flow structures and the experiments are conducted to measure heat/mass transfer coefficients using a naphthalene sublimation technique. For the rotating duct tests, the test duct, which is the cross section of is $20mm\times40mm$ (the hydraulic diameter, $D_h$, of 26.7 mm, has two-pass with $180^{\circ}$ turning and the rectangular ribs on the wall. The rib angle of attack is $70^{\circ}$ and the maximum radius of rotation is $21.63D_h$. The partition wall has 10 mm thickness, which is 0.5 times to the channel width, and the distance between the tip of the partition wall and the outer wall of the turning region is 26.7 mm $(1D_h)$. The turning effect of duct flow makes the very complex flow structure including Dean type vortex and high turbulence, so that the heat/mass transfer increases in the turning region and at the entrance of the second pass. The Coriolis effect deflects the flow to the trailing surface, resulting in enhancement of the heat/mass transfer on the trailing surface and reduction on the leading surface in the first pass. However, the opposite phenomena are observed in the second pass. The each rib arrangement makes different secondary flow patterns. The complex heat/mass transfer characteristics are observed by the combined effects of the rib arrangements, duct rotation and flow turning.

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Development of a muffler for the super heavymachinery in the 70 ton class (70톤 급 초대형 중장비용 머플러 개발)

  • Lee, Shi-Bok;Lee, Won-Tae;Nam, Kyung-Hun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.10
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    • pp.2557-2564
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    • 2009
  • In this study, a muffler for the super heavy machinery in the 70 ton class is developed. Developing process relies on experimental and rule of thumb approach. Various muffler internal structures consisting of partition plates, perforated and non-perforated through pipes, and absorbent are tried and compared for the transmission loss performance. Based on the experimental results, the best combination and locations of the internal acoustic components which affects the muffler performance are determined.

The Design of Technique Based on Partition for Acceleration of ATPG (ATPG 가속화를 위한 분할 기법의 설계)

  • 허덕행
    • Journal of the Korea Society of Computer and Information
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    • v.3 no.2
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    • pp.69-76
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    • 1998
  • To test all internal faults in the case that the number of Primary Input is N, we need patterns that are composed of PI's of maximum 2N. In this paper, we proposed the method to reduce a search space by dividing the multiple output circuit into subcircuit that is related with output. And this method, called PBM(Partition-Based Method), can generate a set of test pattern. The method can effectively generate a test pattern for evaluating all fault of circuit, because the length of input pattern is smaller than that of full circuit and PBM doesn't search any signal line that is not concerned with detecting fault.

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Theoretical Approach to Physical Adsorption of Gases on Solid Surfaces (고체 표면 위의 기체 흡착에 관한 이론적 연구)

  • Chang, Sei-Hun;Pak, Hyung-Suk
    • Journal of the Korean Chemical Society
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    • v.14 no.1
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    • pp.97-107
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    • 1970
  • The grand canonical ensemble partition function for the adsorbed phase of gases on solid surfaces is derived according to the transient state theory of significant liquid structure. The derived adsorption isotherms from the partition function for argon, nitrogen and benzene adsorbed on various adsorbents are in good agreement with the observed values. The surface pressure, the molar entropy, the molar internal energy and the molar heat of adsorption are calculated for benzene adsorbed on graphite. The molar entropy is minimum at near the pressure where a close packed monolayer is formed. The method of parameter determination is illustrated.

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Strengthening Evaluation of Post-Tensioning Due to Anchorage System (정착방법에 따른 외부 프리스트레이트 도입공법의 보강성능 평가)

  • 박승범;홍석주
    • Proceedings of the Korea Concrete Institute Conference
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    • 2000.04a
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    • pp.279-284
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    • 2000
  • The bridge is nation's principal structure and its influence for national economy is enormous. But it is essential for maintenance of deteriorated bridge because of the increased service life and the decreased performance. For the bridge reinforced by continuos slabs and post-tensioning, we evaluate th stress properties of girders and internal support. Results are almost coincidence between measured data in the field and analysed data by computer. We compared the effects by successive order of post- tensioning and order considered distribution of each girder's camber and stress. Bridge's camber and stress showed respectively symmetry and asymmetry shape by post tensioning order. For the effect of post-tensioning force partition, we divided the post-tensioning force into 3 types (100%, 20%, 30%), and the results show t도 difference of final stress and camber.

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The Function Construction based on Modular Design Technique (모듈러 설계기법에 기초한 함수구성)

  • Park, Chun-Myoung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.10a
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    • pp.918-919
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    • 2012
  • This paper present a method of function decomposition and input variable manipulation method based on modular design techniques. We obtain the column multiplicity of decomposition function according to row decomposition method. Also, the proposed partial decomposition function have advantage which is able to omit control function using t-Gate. We find the advantage for internal connection decrement 12% and T-gate number 16%, therefore we find the simple design circuit.

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Sorption and Permeation of Orange II Through Nitrocellulose-Poly (vinylamine) Blended Membranes (니트로셀루로오스-폴리비닐아민 혼합막에 의한 Orange II의 수착과 투과)

  • Tak, Tae-Moon
    • Textile Coloration and Finishing
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    • v.2 no.2
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    • pp.33-38
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    • 1990
  • Nitrocellulose [NC]-Poly(vinylamine) [PVAm] blended membranes with the change of amino group contents were prepared. The sorption and permeation of a mono-sulfonic acid dye, Orange II, in the membranes were investigated by the steady-state permeation method at $50^{\circ}C$ and pH 2.2. The results were discussed in the framework of dual sorption and diffusion theory. It was found that thesorption isotherms comprise a partition and two Langmuir type adsorption having similar binding constants. One of the latter sorption modes is due to unknown adsorption sites in NC and the other is due to the amino groups in PVAm. Apparent diffusion coefficients for collective P and L dye species, $D_P\; and D_L$, were obtained. Interpretation of $D_P$ values leads to two modes of partitions; one is such that dye is immobilized in NC and the other is the dissolution of the dye into the internal water phase.

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