• Title/Summary/Keyword: yield-line method

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Design of Ground Floor Slab According to the Method for Evaluating the Tensile Performance of Steel Fiber Reinforced Concrete (강섬유 보강 콘크리트 인장성능 평가방법에 따른 지반 바닥슬래브의 설계)

  • Lee, Jong-Han;Cho, Baik-Soon;Cho, Chang-Oh
    • Journal of the Korea Concrete Institute
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    • v.28 no.1
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    • pp.95-104
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    • 2016
  • Flexural strength of concrete ground slab reinforced with steel fiber is evaluated using the equivalent flexural strength ratio of steel fiber reinforced concrete based on the yield line theory. Recently, the European standard specifies that the tensile performance of the steel fiber reinforced concrete be evaluated directly from the residual flexural strength after the cracking of concrete. Thus, in the study, an experiment was carried out to evaluate the conventional equivalent flexural strength ratio and the residual flexural strength of the steel fiber reinforced concrete. Then the design flexural strength was investigated according to the location of a point load, based on the ratio of the radius of contact area of the load to the radius of relative stiffness. Design flexural capacity obtained from ACI 360R-10 was smaller than that from TR 34 (2003 & 2013). In addition, TR 34 (2013), which evaluates the design flexural capacity based on the residual flexural strength, showed slightly smaller value than TR 34 (2003).

The Research on SMSR Yield Improvement of the Optical Transceiver Using Modulated DFB Laser (변조된 DFB 레이저를 이용한 광 송수신기의 SMSR 수율 향상에 관한 연구)

  • Kwon, Yoon-Koo;Kim, Chang-Bong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.5
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    • pp.2285-2290
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    • 2011
  • This paper is the research on SMSR yield improvement of the optical transceiver using modulated DFB laser. In general, the wavelength of DFB laser optical transceiver are 1310, 1490 and 1550 nm. Usually SMSR in modulated DFB is difficult to improve as low as 30 dB because of high slop efficiency trade off. In modulation condition, we studied SMSR improvement according to adjust bias current, extinction ratio and optical line terminal receiver sensitivity. As our test results, we can found a method how to improve SMSR for optical transceiver for long distance.

Correlation Coefficient of Leaf Breakdown with Some Agronomic Characters in Flue- Cured Tobacco (Nicotiana tabacum L.) (황색종 연초(Nicotiana tabacum L.)에서 엽탈락과 농경적 형질과의 상관)

  • 조수헌;진정의
    • Journal of the Korean Society of Tobacco Science
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    • v.11 no.2
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    • pp.149-155
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    • 1989
  • This study was conducted to obtain the breeding information for the leaf breakdown, and correlation coefficients between leaf breakdown and some agronomic characters in flue-cured tobacco at Taegu Experiment Station, Korea Ginseng & Tobacco Research Institute. NC 95 and NC 2326 were used as parents. The bulk method procedure was used from the F2 to the F4 generations, 54 plants were selected among F4, and 11 lines were selected among 54 F5 which based on high resistance to bacterial wilt compared with NC2326. The entries were composed of parents and 11 F6 advanced lines, and designed in randomized block with 3 replications. Plant seedlings were transplanted in 16 April. The number of breakdown leaf were investigated at flowering stage, 18 June. There were significant difference between NC 95 and NC 2326 for the number of breakdown leaf, number and weight of ground suckers, days to flower, yield and resistance to bacterial wilt, and similar results were appeared among lines. Estimated heritability in the broad-sense ranged from 59.3% to 87.4% for all characters. Most of genetic correlations were higher than phenotypic coefficients between characters. Number of breakdown leaf was positively correlated with days to flower, the number and weight of ground suckers, while it was negative to yield. One line among 11 had few breakdown leaf, low producted ground suckers and high resistance to bacterial wilt. Above results suggest that the number and weight of ground suckers can be use as a selection criterion for leaf breakdown even under the condition without leaf breakdown.

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Flexural bearing capacity of diaphragm-through joints of concrete-filled square steel tubular columns

  • Rong, Bin;Liu, Rui;Zhang, Ruoyu;Chen, Zhihua;Apostolos, Fafitis
    • Steel and Composite Structures
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    • v.20 no.3
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    • pp.487-500
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    • 2016
  • In order to investigate the flexural bearing capacity of panel zone of diaphragm-through joint between concrete filled square steel tubular column and steel beam, four specimens were tested under static tension loads to study the mechanical properties and bearing capacity of diaphragm-through joints with a failure mode of panel zone. Finite element models of these specimens were developed to simulate the test and compare the predicted failure modes, load-displacement curves and bearing capacities with the experimentally observed. It was found that the tensile load from the steel beam flange is mainly shared by the square steel tube and the diaphragm. The diaphragm plastic zone appears along the cross-section lines enclosed by the square steel tube and the influence of steel beam web on the plastic zone of the steel tube is significant and cannot be neglected. Computational models of yield lines on square steel tube and diaphragm are established based on the distribution pattern of the plastic zone, and an analytical method for the evaluation of the bearing capacity of the joint is proposed. The theoretical results and the experimental data are compared and found in good agreement.

Earth Pressure Analysis of Tunnel Ceiling according to Tunnel Plastic Zone (터널 소성영역에 따른 터널 천단토압 해석)

  • Park, Shin-Young;Han, Heui-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.11
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    • pp.753-764
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    • 2020
  • In this study, the plastic zone and internal earth pressure of the tunnel were calculated using the following three methods: metal plasticity to analyze the deformation of metal during plastic processing, Terzaghi's earth pressure theory from the geotechnical perspective and modified Terzaghi's earth pressure theory, and slip line theory using Mohr-Coulomb yield conditions. All three methods are two-dimensional mathematical analysis models for analyzing the plane strain conditions of isotropic materials. Using the theory of metallurgical plastics, the plastic zone and the internal earth pressure of the ground were obtained by assuming that the internal pressure acts on the tunnel, so different results were derived that did not match the actual tunnel site, where only gravity was applied. An analysis of the plasticity zone and earth pressure via the slip-line method showed that a failure line is formed in a log-spiral, which was found to be similar to the real failure line by comparing the results of previous studies. The earth pressure was calculated using a theoretical method. Terzaghi's earth pressure was calculated to be larger than the earth pressure considering the dilatancy effect.

Measurement of Particles Generated from PECVD Process using ISPM (ISPM을 이용한 PECVD 공정 내 발생입자 측정 연구)

  • Kim, Dongbin;Mun, Jihun;Kim, HyeongU;Kang, Byung Soo;Yun, JuYoung;Kang, SangWoo;Kim, Taesung
    • Particle and aerosol research
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    • v.11 no.4
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    • pp.93-98
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    • 2015
  • Particles which generated from plasma enhanced chemical vapor deposition (PECVD) during thin film deposition process can affect to the process yield. By using light extinction method, ISPM can measure particles in the large-diameter pipe (${\leq}300mm$). In our research, in-situ particle monitor (ISPM) sensor was installed at the 300 mm diameter exhaust-line to count the particles in each size. In-house flange for mounting the transmitting and receiving parts of ISPM was carefully designed and installed at a certain point of exhaust line where no plasma light affect to the light extinction measurement. Measurement results of trend changes on particle count in each size can confirm that ISPM is suitable for real-time monitoring of vacuum process.

Charge Redistribution of Pt-based Alloys

  • Lim, K.Y.;Chung, Y.D.;Kwon, S.Y.;Lee, Y.S.;C.N.Whang;Y.Jeon;Park, B.S.
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.171-171
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    • 1999
  • We studied the charge redistribution in the Pt-M (M=Cu, Co) alloys by X-ray Absorption Near Edge Spectroscopy(XANES) and X-ray Photoelectron Spectroscopy(XPS). These analysis tools provide us information about the charge transfer in the valence band of intermetallic bonding. The samples were prepared by arc-melting method. After annealing this samples in vacuum for several hours, we cold get the ordered samples, which were confirmed with XRD analysis. the core and valence level energy shift in these system were investigated by Mg $K\alpha$(1253.6eV) x-ray source for Pt-Co alloys and monochromatized Al $K\alpha$ (1486.6eV) for Pt-Cu alloys. Pt L2, L3-edge, and Cu, Co K-edge XANES spectra were measured with the total electron-yield mode detector at the 3Cl beam line of the PLS (Pohang light source0. from the changes of White line (WL) area and the core level shifts of the each metal sites, we can obtain the information about the electrons participating in the intermetallic bonding of the Pt-Cu and Pt-Co alloys.

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Resistance to Anthracnose Caused by Colletotrichum acutatum in Chili Pepper(Capsicum annuum L.)

  • Kim, Sang-Hoon;Yoon, Jae-Bok;Do, Jae-Wahng;Park, Hyo-Guen
    • Journal of Crop Science and Biotechnology
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    • v.10 no.4
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    • pp.277-280
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    • 2007
  • Pepper fruit anthracnose, caused by Colletotrichum acutatum, results in serious yield loss and affects crop quality in many Asian countries, making it a disease of economic consequence. A source resistant to C. acutatum was identified by the AVRDC within the line Capsicum chinense Jacq. PBC932. The resistant breeding line C. annuum AR is the $BC_3F_6$ generation derived from C. chinense Jacq. PBC932. The inheritance of resistance to C. acutatum was analyzed in segregating populations derived from the two crosses HN 11$\times$AR and Daepoong-cho$\times$AR. Detached mature green fruits were inoculated using microinjection method. The disease response was evaluated as the disease incidence at 7 DAI. The segregation ratios of resistance and susceptibility to C. acutatum in the $F_2$ and $BC_R$ populations derived from the two crosses fit significantly to a 1:3 Mendelian model. This indicates that the resistance of AR to C. acutatum is controlled by a single recessive gene.

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A Novel Pixel Structure for High Transmission TFT-LCD

  • Shin, Kyoung-Ju;Song, Se-Young;Lee, Il-Pyung;Kim, Chang-Hoon;Jang, Chang-Soon;Chai, Chong-Chul;Souk, Jun-Hyung
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.208-210
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    • 2008
  • We have developed a LCD Panel that form storage capacitance for pixels between pixel electrode of bottom glass and common electrode of top glass. This method could make higher transmission and higher production yield than before by removing storage electrode line and capacitance on the bottom glass by simplifying bottom pixel structure.

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Chromosomal Microarray Testing in 42 Korean Patients with Unexplained Developmental Delay, Intellectual Disability, Autism Spectrum Disorders, and Multiple Congenital Anomalies

  • Lee, Sun Ho;Song, Wung Joo
    • Genomics & Informatics
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    • v.15 no.3
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    • pp.82-86
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    • 2017
  • Chromosomal microarray (CMA) is a high-resolution, high-throughput method of identifying submicroscopic genomic copy number variations (CNVs). CMA has been established as the first-line diagnostic test for individuals with developmental delay (DD), intellectual disability (ID), autism spectrum disorders (ASDs), and multiple congenital anomalies (MCAs). CMA analysis was performed in 42 Korean patients who had been diagnosed with unexplained DD, ID, ASDs, and MCAs. Clinically relevant CNVs were discovered in 28 patients. Variants of unknown significance were detected in 13 patients. The diagnostic yield was high (66.7%). CMA is a superior diagnostic tool compared with conventional karyotyping and fluorescent in situ hybridization.