• Title/Summary/Keyword: 이두식

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A New Refined Truss Modeling for Shear-Critical RC Members (Part I) - lts derivation of Basic Concept - (전단이 지배하는 RC부재의 새로운 트러스 모델링 기법 연구 (전편) - 기본 개념 유도를 중심으로 -)

  • Kim Woo;Jeong Jae-Pyong;Kim Dae-Joong
    • Journal of the Korea Concrete Institute
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    • v.16 no.6 s.84
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    • pp.785-794
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    • 2004
  • This paper describes a new refined truss modeling technique derived based on the well-known relationship of V=dM/dx=zdT/dx+Tdz/dx in a reinforced concrete beam subjected to combined shear and moment loads. The core of the model is that a new perspective on the shear behavior can be gained by considering the variation of the internal arm length along the span, so that the shear resistance mechanism can be expressed by the sum of two base components; arch action and beam action. The sharing ratio of these two actions is determined by accounting for the compatibility of deformation associated to the two actions. Modified Compression Field Theory and the tension-stiffening effect formula in CEB/FIP MC-90 are employed in calculating the deformations. Then the base equation of V=dM/dx has been numerically duplicated to form a new refined truss model.

Esophagectomy with Operating Mediastinoscope (종격동경을 이용한 식도절제수술 -1례-)

  • 윤용한;이두연;이성수
    • Journal of Chest Surgery
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    • v.31 no.11
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    • pp.1110-1115
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    • 1998
  • Esophagectomy has a high morbidity rate, mainly related to pulmonary complications. The respiratory morbidity of open esophagectomy is high, ranging from 6% to 10%. This high morbidity is partially responsible for the 6∼15% mortality rate of esophagectomy. Many techniques of esophagectomy without thoracotomy have been described since the initial report of Orringer and Sloan. Endoscopic microsurgical dissection of the esophagus was clinically introduced in 1989. Endoscopic microsurgical dissection of the esophagus was developed as a minimally invasive procedure that avoids thoracotomy and provides precise vision during the operation in order to reduce mediastinal trauma and to improve the peri- and post-operative situation. A 20 year-old women who accidentally swallowed about 150 cc of glacial acetic acid underwent an esophagectomy using the operating mediastinoscopy, cervical esophagogastric anastomosis, pyloromyotomy, and feeding jejunostomy tube placement for esophageal stricture. The postoperative course was uneventful and the patient was discharged on the 17th postoperative day. Our clinical experience shows that endoscopic microsurgical dissection of esophagus is a safe and feasible method because it offers excellent optical control and enables the surgeon to operate in a minimally invasive manner.

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Analysis of Quadratically Filtered Gradient Algorithm with Application to Channel Equalization (채널 등화기에 응용한 제2차 필터화 경사도 알고리즘의 해석)

  • 김해정;이두수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.1
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    • pp.131-142
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    • 1994
  • This paper analyzes the properties of such algorithm that corresponds to the nonlinear adaptive algorithm with additional update terns, parameterized by the scalar factors ${\alpha}1,\;and\;{\alpha}2$. The analysis of concergence leads to eigenvalues of the transition matrix for the mean filter coefficient vector. Regions in which the algorithm becomes stable are demonstrated. The time constant is derived and the computational complexity of the QFG algorithm is compared with those of the conventional LMS. sign, and LFG algorithm. The properties of convergence in the mean square error is derived and the neccessary condition for the CFG algorithm to be stable is attaned. In the computer simulation a channel equalization is utilized to demonstrate the performance feature of the QFG algorithm. The QFG algorithm has the more computational complexities but the faster convergence speed than LMS and LFG algorithm. Since the QFG algorithm has smoother convergence, it may be useful in case where error bursting is a problem.

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Application and Evaluation of the Sheet Flow Channel for Water Quality Improvement in the Stream (하천 내 수질 개선을 위한 박층류 하도의 적용 및 평가)

  • Lee, Du Han;Kim, Myounghwan;Gu, Jung-Eun;Kim, Won
    • Ecology and Resilient Infrastructure
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    • v.6 no.4
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    • pp.208-216
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    • 2019
  • This study investigated design factors and removal efficiencies of a sheet flow channel as natural type water improvement techniques in the stream. The channel was designed considering the design factors, then constructed and monitored in the test bed of the Osan stream's floodplain. Water lever, velocity, discharge, T-P, T-N, and NO3-N were monitored and the removal efficiencies and design formula were suggested. Overall efficiencies of T-P, T-N, and NO3-N range 10 - 20%, and they show consistent relations with residence times. Minimum velocity requirement is also suggested from the relation of algae conditions and velocities. Relation formula of residence time and removal efficiency will be applicable in the design and operation process of a sheet flow channel.

The Rigidity of Transverse Intermediate Stiffener of Horizontally Curved Plate Girder Web Panels (강곡선 플레이트거더 복부판의 중간수직보강재 소요강성에 관한 연구)

  • Lee, Doo Sung;Park, Chan Sik;Lee, Sung Chul
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4A
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    • pp.735-742
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    • 2006
  • In this study, the ultimate shear strength behavior of transversely stiffened curved web panels was investigated through nonlinear finite element analysis. It was found that if the transverse stiffener has a sufficient rigidity, then curved web panels used in practical designs are able to develop the postbuckling strength that is equivalent to that of straight girder web panels having the same dimensional and material properties. The nonlinear analysis results indicate that in order for curved web panels to develop the potential postbuckling strength. The rigidity of the transverse stiffener needs to be increased several times the value obtained from the Guide Specifications (AASHTO, 2003). However, in the case of thick web panels where the shear design is governed by shear yielding, the stiffener rigidity does not have to be increased. From the analysis results, a simple design formula is suggested for the rigidity of transverse stiffener under strength limit state.

Structural Performance and Behavior of Concrete Floating Container Terminal by Live Load Distributions (활하중 분포에 따른 콘크리트 부유식 컨테이너 터미널의 구조성능 및 거동)

  • Lee, Du-Ho;Jeong, Yun-Ju;You, Young-Jun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.19 no.1
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    • pp.72-80
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    • 2015
  • In this study, comparative analysis has been performed with regard to a bending stress and deformation at bottom slab of a concrete floating container terminal by live load distributions. In addition, a structural performance and behavior of the floating structure is considered using a numerical analysis. Through reviewed structural performance of a floating structure by live load distribution, the structure presented tensile behavior by two live load cases (A, B, D-type). Then, the other live load cases (C, E, F, G, H, I, J-type) shows compressive behavior. Especially, immoderately compressive stress was generated on bottom slab at specific load distribution. but, that should be decreased through controling buoyancy pre-flexion. Through reviewed structural behavior, slopes of structure by four live load cases (B, E, F, H-type) were exceeded in design criteria of mega-float. It should be estimated that it get out of the load case at loading container. In all, the present study can be considered as a benchmark of a floating container terminal in the absence of analysis and will be used to guide-line about serviceability of concrete floating container terminal.

Studies on isolation of rhinopneumonitis virus from Korean horses and its immunogenicity II. Studies on characters and immunogenicity of equine herpesvirus (국내 말로부터 비폐렴바이러스의 분리 및 면역원성에 관한 연구 II. 국내 분리 말 비폐렴바이러스의 특성 및 면역원성 조사)

  • Cho, Gil-jae;Kim, Bong-hwan;Lee, Du-sik;Oh, Moon-you;Ko, Mi-hee
    • Korean Journal of Veterinary Research
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    • v.35 no.4
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    • pp.743-752
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    • 1995
  • The study was carried out to characterize the properties of Korean isolates of EHV from aborted fetuses and determine envelope protein profiles. The results obtained were summarized as follows; 1. Two strains of EHV was isolated from 2 liver samples among 10 aborted fetuses from which the virus isolation was attempted. 2. Morphological and some enzymatic properties of the Korean isolates of EHV which was designated as $LC_1$ and $LC_2$ was identical to those of a reference strain of Australia-N of EHV-1. The Korean isolates of EHV could be propagated on ED cell culture and they formed typical plaques 1 to 2 days after infection in the ED cells from which typical cuboidal particles of 150~170 nm diameter herpesvirus were observed. The virus could be detected specifically from neucleus and cytoplasm of infected cells by flourescent antibody technique using FITC labelled anti-Aust IV(EHV-1) antiserum. The Korean isolates, $LC_1$ and $LC_2$ were specifically neutralized by anti Aust IV antiserum and reacted positively to CELISA. 3. The structural polypeptides of purified enveloped virions of $LC_1$ and $LC_2$ isolates of EHV were determined by SDS-polyacrylamide gel electrophoresis to identify the envelope glycoproteins. $LC_1$ and $LC_2$ strains revealed 14 glycoproteins ranging in molecular weight from 190 kD to 31 kD while 17 structural proteins of Aust IV(EHV-1), of which 14 were identical to those of $LC_1$ and $LC_2$, were identified. Upon immunoblotting by rabbit antiserum against EHV isolates and EHV-1(Aust IV), 4 immunogenic proteins of $LC_1$ and $LC_2$ were 135 kD, 88 kD, 64 kD and 59 kD, of which 135 kD, 88 kD and 64 kD proteins were also found in Aust IV(EHV-1).

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Demyelination in natural canine distemper encephalomyelitis : An immunohistochemical study of myelin basic protein, myelin associated glycoprotein and glial fibrillary acidic protein in the lesion of demyelination (홍역이환개에서 발생한 수초탈락성 뇌척수염 : 수초탈락부위에서 MBP, MAG 및 GFAP의 면역조직학적 관찰)

  • Shin, Tae-kyun;Kwon, Oh-deog;Lee, Du-sik;Lee, Cha-soo
    • Korean Journal of Veterinary Research
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    • v.33 no.2
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    • pp.295-300
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    • 1993
  • Central nervous system of two dogs with natural canine distemper was investigated histopathologically and immunocytochemically with antisera to MBP, MAG and GFAP. Histopathologically, there were neuronal degeneration and diffuse gliosis in the cerebrum, vacuolar degeneration, hypertrophy of astrocytes and demyelination in cerebellar white matter adjacent to the 4th ventricle and optic tracts showing non-inflammatory demyelinating encephalomyelitis (Summers and Appel, 1987). Immunohistochemically, there was a concurrent disappearance of MBP and MAG in the well developed demyelinating lesion in the cerebellar white matter. At the margin of demyelination, Loss of both MBP and MAG varied on the stage of demyelinating process. GFAP-positive astrocytes were hypertrophied and contained canine distemper virus intranuclear inclusions. GFAP-positive fibers were increased at the early stage of demyelination, and then were not immunoreaeted at the well developed demyelination. Hypertrophic astrocytes with intranuclear inclusions were commonly identified in the interfascular layer without myelin vacuolation and demyelination. This is the first study of primary demyelination and astroglial reactions in natural CDE investigated using immunocytochemistry of two myelin proteins and GFAP. Concurrent loss of MBP and MAG suggest that the myelin sheath is the target in the demyelinating process in CDE.

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Genetic studies of blood markers in Cheju horses II. Blood protein types (제주마의 혈액형에 관한 연구 II. 혈액 단백질형)

  • Cho, Gil-jae;Kim, Bong-hwan;Lee, Du-sik;Lee, Kyoung-kap
    • Korean Journal of Veterinary Research
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    • v.40 no.2
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    • pp.283-290
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    • 2000
  • The present study was carried out to investigate the blood markers of Cheju horses. The blood protein types (biochemical polymorphism) were tested from 73 Cheju native horses (CNH) and 118 Cheju racehorses(CRH) by horizontal polyacrylamide gel electrophoresis (HPAGE), isoelectric focusing (IEF) and starch gel electrophoresis (SGE). At the same time, their phenotypes and gene frequencies were studied. The biochemical polymorphism phenotypes observed with high frequency were A1B-KK(97.3%), ALB-AB(49.3%), AP-SS(100%), ES-II(30.1%), GC-FF(87.7%), HB-BIBI(49.3%), TF-F2R(41.1%), TF-EF2(8.2%), PGD-FF(97.3%), PGM-SS(50.7%), GPI-II(74.0%) in CNH, While A1B-KK(99.2%), ALB-BB(50.8%), AP-SS(99.2%), ES-II(42.4%), ES-IS(14.4%), GC-FF(95.8%), HBB-IB II(39.8%), TF-F2R(21.2%), PGD-FF(77.1%), PGD-SS(4.3%), PGM-SS(72.9%), GPI-II(90.7%) in CRH. Alleles observed with high frequency were $AlB^{K}$(0.986), $ALB^{B}$(0.616), $AP^{S}$(1.000), $ES^{I}$(0.479), $ES^{F}$(0.274), $GC^{F}$(0.938), $GPI^{I}$(0.856), $HB^{BI}$(0.685), $PGD^{F}$(0.993), $PGM^{S}$(0.753), $TF^{F2}$(0.404), $TF^{R}$(0.397) in CNH and $AlB^{K}$(0.996), $ALB^{B}$(0.720), $AP^{S}$(0.996), $ES^{I}$(0.661), $ES^{F}$(0.203), $GC^{F}$(0.979), $GPI^{I}$(0.936), $HB^{BI}$(0.534), $PGD^{F}$(0.864), $PGM^{S}$(0.852), $TF^{F2}$(0.428), $TF^{R}$(0.272) in CRH. $TF^{E}$(0.041) allele and silent gene($ES^{I{^*}}$ : 0.014) were observed in CNH. The mean heterozygosity in CNH and CRH was observed 0.2974 and 0.2864, respectively.

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i-LEACH : Head-node Constrained Clustering Algorithm for Randomly-Deployed WSN (i-LEACH : 랜덤배치 고정형 WSN에서 헤더수 고정 클러스터링 알고리즘)

  • Kim, Chang-Joon;Lee, Doo-Wan;Jang, Kyung-Sik
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.1
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    • pp.198-204
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    • 2012
  • Generally, the clustering of sensor nodes in WSN is a useful mechanism that helps to cope with scalability problem and, if combined with network data aggregation, may increase the energy efficiency of the network. The Hierarchical clustering routing algorithm is a typical algorithm for enhancing overall energy efficiency of network, which selects cluster-head in order to send the aggregated data arriving from the node in cluster to a base station. In this paper, we propose the improved-LEACH that uses comparably simple and light-weighted policy to select cluster-head nodes, which results in reduction of the clustering overhead and overall power consumption of network. By using fine-grained power model, the simulation results show that i-LEACH can reduce clustering overhead compared with the well-known previous works such as LEACH. As result, i-LEACH algorithm and LEACH algorithm was compared, network power-consumption of i-LEACH algorithm was improved than LEACH algorithm with 25%, and network-traffic was improved 16%.