• 제목/요약/키워드: complementary work

검색결과 168건 처리시간 0.025초

응력함수에 기초한 복합 하중하의 복합재 적층판의 층간응력 해석 (Stress Function-Based Interlaminar Stress Analysis of Composite Laminates under Complex Loading Conditions)

  • 김흥수;김정윤;김진곤
    • 동력기계공학회지
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    • 제14권3호
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    • pp.52-57
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    • 2010
  • Interlaminar stresses near the free edges of composite laminates have been analyzed considering wall effects. Interface modeling of bonding layer was introduced to explain the wall effect. Using Lekhnitskii stress functions and the principle of complementary virtual work, the interlaminar stresses were obtained, which satisfied the traction free boundary conditions not only at the free edges, but also at the top and bottom surfaces of laminates. The interface modeling provides not singular stresses but concentrated finite interlaminar stresses. The significant amount of reductions of stresses at the free edge are observed compared to the results without interface modeling. The real stress state can be predicted accurately and the results demonstrate the usefulness of the proposed interface modeling for the strength design of composite laminates.

A Study on Assessment of Composite Couplings for Helicopter Rotor Blades with Multi-cell Sections

  • Jung, Sung-Nam;Park, Il-Ju;Shi, Eui-Sup;Chopra, Inderjit
    • International Journal of Aeronautical and Space Sciences
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    • 제4권1호
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    • pp.9-18
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    • 2003
  • In this work, a closed-form analysis is performed for the structural response of coupled composite blades with multi-cell sections. The analytical model includes the effects of shell wall thickness, transverse shear, torsion warping and constrained warping. The mixed beam approach based on Reissner's semi-complementary energy functional is used to derive the beam force-displacement relations. The theory is validated against experimental test data and other analytical results for coupled composite beams and blades with single-cell box-sections and two-cell airfoils. Correlation of the present method with experimental results and detailed finite element results is found to be very good.

Multi-trade Prefabrication 기법 적용을 위한 기술적 요구사항 분석 (Analysis of Technical Requirement for Implementation of Multi-trade Prefabrication)

  • 장세준;이강
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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    • pp.113-114
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    • 2016
  • This paper proposes a technical requirements analysis of implementation of multi-trade prefabrication. Recently, there has been a rise in the use of prefabrication to minimize on-site work for time reduction to increase productivity. Prefabrication technique is evolved into multi-trade prefabrication combining other trades from single-trade prefabrication. For implementation of new technique, not only itself but complementary techniques have to be prepared. In this paper, MEP corridor rack, a major item of multi-trade prefabrication, was implemented in the test bed and its process was analyzed to find out technical requirements. As a result, comparatively high level of IT technique was required for efficient use of multi-trade prefabrication in design, lifting and construction phase. In design phase, component level of BIM library was needed for manufacturing; and in lifting phase, BIM-based site logistics process was required. Also in construction phase, laser scanning was implemented for gathering shape and geometry of the wall and slab that were attached to multi-trade prefabrication module.

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An Optimization-based Computational Method for Surface Fitting to Update the Geometric Information of An Existing B-Rep CAD Model

  • Louhichi, Borhen;Aifaoui, Nizar;Hamdi, Mounir;BenAmara, Abdelmajid;Francois, Vincent
    • International Journal of CAD/CAM
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    • 제9권1호
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    • pp.17-24
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    • 2010
  • For several years, researchers have focused on improving the integration of the CAD, CAM and Analysis through a better communication between the various analysis tools. This tendency to integrate the CAD/Analysis and automation of the corresponding processes requires data sharing between the various tasks using an integrated product model. We are interested in this research orientation to CAD/CAM/Analysis integration by rebuilding the CAD model (BREP), starting from the Analysis results (deformed mesh). Because this problem is complex, it requires to be split into several complementary parts. This paper presents an original interoperability process between the CAD and CAE. This approach is based on a new technique of rebuilding the CAD surface model (Nurbs, Bezier, etc.) starting from triangulation (meshed surface) as a main step of the BREP solid model. In our work, the advantages of this approach are identified using a centrifugal pump example.

ALU의 개발을 위한 RSFQ DFFC 회로의 설계 (RSFQ DFFC Circuit Design for Usage in developing ALU)

  • 남두우;김규태;강준희
    • 한국초전도저온공학회:학술대회논문집
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    • 한국초전도저온공학회 2003년도 추계학술대회 논문집
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    • pp.123-126
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    • 2003
  • RSFQ (Rapid Single Flux Quantum) circuits are used in many practical applications. RSFQ DFFC (Delay Flip-Flop with complementary outputs) circuits can be used in a RAM, an ALU (Arithmetic Logic Unit), a microprocessor, and many communication devices. A DFFC circuit has one input, one switch input, and two outputs (output l and output 2). DFFC circuit functions in such way that output 1 follows the input and output 2 is the complement of the input when the switch input is "0." However, when there is a switch input "1."the opposite output signals are generated. In this work, we have designed an RSFQ DFFC circuit based on 1 ㎄/$\textrm{cm}^2$ niobium trilayer technology. As circuit design tools, we used Xic, WRspice, and Lmeter After circuit optimization, we could obtain the bias current margins of the DFFC circuit to be above 32%.

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High Embedding Capacity and Robust Audio Watermarking for Secure Transmission Using Tamper Detection

  • Kaur, Arashdeep;Dutta, Malay Kishore
    • ETRI Journal
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    • 제40권1호
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    • pp.133-145
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    • 2018
  • Robustness, payload, and imperceptibility of audio watermarking algorithms are contradictory design issues with high-level security of the watermark. In this study, the major issue in achieving high payload along with adequate robustness against challenging signal-processing attacks is addressed. Moreover, a security code has been strategically used for secure transmission of data, providing tamper detection at the receiver end. The high watermark payload in this work has been achieved by using the complementary features of third-level detailed coefficients of discrete wavelet transform where the human auditory system is not sensitive to alterations in the audio signal. To counter the watermark loss under challenging attacks at high payload, Daubechies wavelets that have an orthogonal property and provide smoother frequencies have been used, which can protect the data from loss under signal-processing attacks. Experimental results indicate that the proposed algorithm has demonstrated adequate robustness against signal processing attacks at 4,884.1 bps. Among the evaluators, 87% have rated the proposed algorithm to be remarkable in terms of transparency.

Large Calibration Chamber의 개발 (Development of Large Calibration Chamber System)

  • 정충열;김태준;김대규;이우진
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 봄 학술발표회 논문집
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    • pp.673-678
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    • 2002
  • Laboratory calibration chamber tests for cone penetrometers, pressuremeters and dilatometers in cohesionless soil specimens have been conducted by numerous researchers. However, there have been only few applications to compacted or preconsolidated cohesive soils. Therefore, for the first time, Calibration Chamber System was developed in Korea University. This can be attributed to the extremely time consuming and laborious process involved in the preparation of large cohesive soil specimens in addition to other complexities involving instrumentation for pore pressure monitoring and the need for maintaing saturation by back pressure. Chamber System with similar principle as LSU Chamber System was made of more strengthen and complementary form by increasing system diameter(1.2m), carrying out 1st and 2nd consolidation process in one system for smooth and safe work, accurate Data Aquisition.

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Display System Design Based On The Abstraction Hierarchy

  • Sohn, Kwang-Young;Shin, Hyun-Kook
    • Nuclear Engineering and Technology
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    • 제28권3호
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    • pp.339-348
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    • 1996
  • Plant monitoring algorithm developments seem to be saturated which means that display system to show the results from the algorithm should be the well-defined and interactive tools for operator's diagnosing, controlling, restoring the abnormal plant situations. On the other hand, very little generalized display design concepts and evaluations are available. Events that are unfamiliar to operators and that has not been anticipated by designers may cause great threats to the nuclear power plant system safety operation. The abstraction hierarchy, considered most popular display design methodology but not generalized for nuclear power plant design space, has ken proposed as a representation frame work that can be adopted to design interfaces and supports operators in diagnosing overlooked events that should have been considered to operate plant safely. However most practical plant display systems do not fully stick to this design concept but partially rely on their philosophy from design experiences. Abstraction hierarchy display design concept will be do scribed and the trend of Advanced Control Room(ACR) CRT design will also be presented with the conventional display for the several type of plants. Consequently this complementary material should be of interest to designer and regulators concerned with nuclear power plant.

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클라우드 서비스 품질·성능 관리체계의 개선방안 (Improvement of Cloud Service Quality and Performance Management System)

  • 김남주;함재춘;서광규
    • 반도체디스플레이기술학회지
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    • 제20권4호
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    • pp.83-88
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    • 2021
  • Cloud services have become the core infrastructure of the digital economy as a basis for collecting, storing, and processing large amounts of data to trigger artificial intelligence-based services and industrial innovation. Recently, cloud services have been spotlighted as a means of responding to corporate crises and changes in the work environment in a national disaster caused by COVID-19. While the cloud is attracting attention, the speed of adoption and diffusion of cloud services is not being actively carried out due to the lack of trust among users and uncertainty about security, performance, and cost. This study compares and analyzes the "Cloud Service Quality and Performance Management System" and the "Cloud Service Certification System" and suggests complementary points and improvement measures for the cloud service quality and performance management system.

A NEW MELANOGENESIS INHIBITOR FROM INGA ALBA (SW.) WILLD.

  • Danoux, L.;Henry, F.;Moser, P.;lGillon, V.;Moretti, C.;Pauly, G.
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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    • pp.520-539
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    • 2003
  • By using sequentially efficacy tests based on tyrosinase, the key enzyme of melanogenesis, then a cell line of melanocytes cultured in vitro, we have been able to detect the whitening potential of a plant extract and then to develop a new whitening Active Ingredient whose the whitening potential was confirmed on cultured melanocytes. Through a phytochemical approach, it seems that the whitening potential could be due to the "tannin" fraction of plant extract. A complementary work is planned to explain more precisely which fractions are responsible for the whitening potential and a clinical test is in progress on 30 Asian skin type volunteers to show the whitening efficacy on human volunteers.

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