• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2001년도 Proceedings of 2001 International Symposium
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• pp.35-39
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• 2001

The Integration Host factor (IHF) of Escherichia coli is a small, basic protein that is required for a variety of functions including site-specific recombination, transposition, gene regulation, plasmid replication, and DNA packaging. It ,is composed of two subunits that are encoded by the ihfA ($\alpha$-subunit) and ihjB ($\beta$-subunit) genes. IHF binding sites are composed of three elements called the WATCAR, TTG, and poly (dAT) elements. We have characterized IHF binding to the H site of bacteriophage λ. We have isolated suppressors that bind to altered H' sites using a challenge phage selection. Two different suppressors were isolated that changed the adjacent $\alpha$P64 and $\alpha$K65 residues. The suppressors recognized both the wild-type site and a site with a change in the WATCAR element. Three suppressors were isolated at $\beta$-E44. These suppressors bound the wild-type and a mutant site with a T：A to A：T change (H44A) in the middle of the TIR element. Site-directed mutagenesis was used to make several additional changes at $\beta$E44. The wild-type and $\beta$E44D mutant could not bind the wild-type site but were able to bind the H44A mutant site. Other mutants with neutral, polar, or a positive charge at $\beta$E44 were able to repress both the wild-type and H44A sites. Examination of the IHF crystal structure suggests that the ability of the wild-type and $\beta$E44D proteins to discriminate between the T：A and A：T basepairs is due to indirect interactions. The $\beta$-E44 residue does not contact the DNA directly. It imposes binding specificity indirectly by interactions with residues that contact the DNA. Details of the proposed interactions are discussed.

• 대한조선학회논문집
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• 제33권3호
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• pp.56-65
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• 1996

최근 재료 과학의 발달과 함께 선박의 초고속화를 추구함에 따라 높은 강도와 중량의 경량화를 동시에 만족시킬 수 있는 복합 재료에 대한 요구가 증대되고 있다. 샌드위치 구조 형식은 두껍고 약한 저밀도의 심재와 얇고 강한 고밀도의 면재가 접착된 복합 구조의 한 형태로서 두 개의 면재가 중립 축으로부터 멀리 떨어지게 됨으로써 2차 모멘트가 크게 되어 구조의 강성을 증가시킬 수 있는 가장 효과적인 경량의 구조 형식이다. 본 연구에서는 샌드위치 평판 구조가 분포 하중, 압축 하중, 전단 하중 및 이 들의 복합하중을 받을 때의 응력 및 좌굴 하중을 Rayleigh-Ritz법을 이용하여 정밀 해석하였다. 그리고, 샌드위치 평판에 대한 초기 설계에 응용이 가능하도록 좌굴응력 외에 Wrinkling 응력에 관한 제한조건을 고려하여 샌드위치 평판의 최소 중량 설계를 수행하였다.

• Clinics in Shoulder and Elbow
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• 제27권1호
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• pp.88-107
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• 2024

The aim of this systematic review was to collect evidence on the following 10 technical aspects of glenoid baseplate fixation in reverse total shoulder arthroplasty (rTSA): screw insertion angles; screw orientation; screw quantity; screw length; screw type; baseplate tilt; baseplate position; baseplate version and rotation; baseplate design; and anatomical safe zones. Five literature libraries were searched for eligible clinical, cadaver, biomechanical, virtual planning, and finite element analysis studies. Studies including patients >16 years old in which at least one of the ten abovementioned technical aspects was assessed were suitable for analysis. We excluded studies of patients with: glenoid bone loss; bony increased offset-reversed shoulder arthroplasty; rTSA with bone grafts; and augmented baseplates. Quality assessment was performed for each included study. Sixty-two studies were included, of which 41 were experimental studies (13 cadaver, 10 virtual planning, 11 biomechanical, and 7 finite element studies) and 21 were clinical studies (12 retrospective cohorts and 9 case-control studies). Overall, the quality of included studies was moderate or high. The majority of studies agreed upon the use of a divergent screw fixation pattern, fixation with four screws (to reduce micromotions), and inferior positioning in neutral or anteversion. A general consensus was not reached on the other technical aspects. Most surgical aspects of baseplate fixation can be decided without affecting fixation strength. There is not a single strategy that provides the best outcome. Therefore, guidelines should cover multiple surgical options that can achieve adequate baseplate fixation.

• 콘크리트학회논문집
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• 제11권6호
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• pp.13-24
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• 1999

The external, unbonded prestressed concrete(PSC) members exhibit very different structural behavior from that of internal bonded PSC members because of eccentricity change and slip occurrence during loading process. The purpose of the present study is to propose the ultimate failure stresses of prestressing (PS) steels for those external unbonded PSC members. To this end, a comprehensive analysis has been made using the nonlinear finite element analysis program developed recently for external unbonded PSC members by authors. A series of major influencing variables have been included in the analysis. It was found that the span-depth ratio, neutral axis depth-effective depth ratio, load geometry, amount of ordinary steel, and prestressing steel ration have great influence for the ultimate failue stress of PS steel is preposed and is compared with experimental dat as well as existing formulas for internal unbonded members. The Comparison indicates that the proposed equation agrees relatively well with experimental data and that existing formulas including ACI and AASHTO equations show some discrepancies from experimental ones. The present study allows more realistic analysis and design of prestressed concrete structures with external unbonded tendons.

• 전력전자학회논문지
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• 제11권2호
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• pp.172-183
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• 2006

본 논문은 Akagi에 의해 발표된 p-q 이론과 Nabae 및 Peng에 의하여 발표된 크로스벡터 이론의 대비를 통하여 3상 4선 계통에서 순시전력보상방법을 분석한다. 3상 3선 계통에서 영상성분 전압이 없는 경우 두 이론은 똑같다. 그렇지만 3상 4선 계통에서 영상성분 전압과 전류가 포함되는 경우, 두 이론은 순시무효전력과 순시유효전력을 달리 정의한다. 본 논문에서는 이론적 분석과 컴퓨터 시뮬레이션을 바탕으로 영상성분 전압과 영상성분 전류가 존재하는 3상 4선 계통에서 에너지 저장요소의 필요 없이 무효전력만의 보상을 통하여 계통의 중성선 전류를 완벽히 제거할 수 있는 순시전력보상방법을 제시한다.

• Steel and Composite Structures
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• 제15권6호
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• pp.623-643
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• 2013

Concrete filled steel tubular members (CFST) become a popular choice for modern building construction due to their numerous structural benefits and at the same time aging of those structures and member deterioration are often reported. Therefore, actions like implement of new materials and strengthening techniques become essential to combat this problem. The application of carbon fibre reinforced polymer (CFRP) with concrete structures has been widely reported whereas researches related to strengthening of steel structures using fibre reinforced polymer (FRP) have been limited. The main objective of this study is to experimentally investigate the suitability of CFRP to strengthening of CFST members under flexure. There were three wrapping schemes such as Full wrapping at the bottom (fibre bonded throughout entire length of beam), U-wrapping (fibre bonded at the bottom throughout entire length and extended upto neutral axis) and Partial wrapping (fibre bonded in between loading points at the bottom) introduced. Beams strengthened by U-wrapping exhibited more enhancements in moment carrying capacity and stiffness compared to the beams strengthened by other wrapping schemes. The beams of partial wrapping exhibited delamination of fibre and were failed even before attaining the ultimate load of control beam. The test results showed that the presence of CFRP in the outer limits was significantly enhanced the moment carrying capacity and stiffness of the beam. Also, a non linear finite element model was developed using the software ANSYS 12.0 to validate the analytical results such as load-deformation and the corresponding failure modes.

• 한국언어정보학회지:언어와정보
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• 제10권1호
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• pp.1-20
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• 2006

We can distinguish two different groups of 'fusion expressions' depending on whether the verb (-ko) ha- 'do' can be recovered from the contracted expression concerned or not: recoverable and unrecoverable fusion expressions. Many expressions belonging to the former group show alternations between the [da]-type and the [dae]-type: e.g., o-nta-nta and o-ntae-nta '...says... is coming.' On the other hand, some expressions like ka-ntae can only be realized as the [dae]-type. The main purpose of this paper is to account for these [dae]-type expressions. First, we assume that they have an inaudible/invisible quotation $verb\;{\phi}-$, which takes as its complement a verb phrase with a neutral speech-level ending. This quotation verb is derived from the quotation verb ha-. Second, we assume that the quotation $verbs\;{\phi}-$ and ha- have the [j] sound as their stem-final element, which means that these verbs are actually represented as ${\phi}-j-$ and ha-j-, respectively. In this system, the [tae]-type expressions come out naturally from the behavior of the [j] sound. We do not employ any ad hoc phonological rules to derive the [dae]-type expressions from the corresponding [da]-type expressions.

• Steel and Composite Structures
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• 제22권4호
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• pp.837-853
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• 2016

This paper presents the experimental and numerical study on the distribution of transverse and longitudinal residual stresses in cold-formed thick-walled structural steel rectangular hollow sections manufactured by indirect technique. Hole-drilling method is employed to measure the magnitude of the transverse and longitudinal surface residual stress distribution, and the effects of the residual stresses are evaluated qualitatively by sectioning method. It is shown that compared to normal cold-formed thin-walled structural hollow sections (SHS), the cold-formed thick-walled SHS has similar level of residual stress in the flat area but higher residual stresses in the corner and welding areas. Both the transverse and longitudinal residual stresses tend to open the section. In order to predict the surface residual stresses in the corners of the cold-formed thick-walled SHS, an analytical model is developed. 2D finite element simulation of the cold bending process is conducted to validate the analytical approach. It is shown that in analyzing bending for thick-walled sections, shifting of neutral axis must be considered, since it would lead to nonlinear and non-symmetrical distribution of stresses through the thickness. This phenomenon leads to the fact that cold-formed thick-walled SHSs has different distribution and magnitude of the residual stresses from the cold-formed thin-walled SHSs.

• 한국의류학회지
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• 제32권8호
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• pp.1264-1273
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• 2008

The purpose of this study is to analyze protection functionality of supermodern fashion which is shown by responding to supermodern environment, where non-spaces increases in the 21st modern city. The theoretical background is drawn for supermodern environment theory. For the study, he researcher used existing study and specialized book and analyzed photograph materials by selecting them in specialized fashion book, internet site and designer's collection. The works from 1995 S/S collection to 2008 S/S collection are analyzed. The result of this study is as follow. First, supermodern design is adopting the shape of high-functional element, electronic device, protective device to protect wearer in non-space. Second, in order to mentally protect individual anonymous leadership of interaction is granted by adopting hood, veil or mask. Third, supermodern design is creating independent and user-based space by shape transformation in change of urban environment. Fourth, in order to protect wearer through camouflage or concealment, camouflage pattern or neutral color are used.

• Computers and Concrete
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• 제1권2호
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• pp.211-226
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• 2004

A relatively simple multiple-vertical-line-element macro model has been incorporated into a standard computer code DRAIN-2D. It was used in blind predictions of seismic response of cantilever RC walls subjected to a series of consequent earthquakes on a shaking table. The model was able to predict predominantly flexural response with relative success. It was able to predict the stiffness and the strength of the pre-cracked specimen and time-history response of the highly nonlinear wall as well as to simulate the shift of the neutral axis and corresponding varying axial force in the cantilever wall. However, failing to identify the rupture of some brittle reinforcement in the third test, the model was not able to predict post-critical, near collapse behaviour during the subsequent response to two stronger earthquakes. The analysed macro model seems to be appropriate for global analyses of complex building structures with RC structural walls subjected to moderate/strong earthquakes. However, it cannot, by definition, be used in refined research analyses monitoring local behaviour in the post critical region.