• 제목/요약/키워드: Functional force

검색결과 525건 처리시간 0.027초

타원형 단면형상을 갖는 복합재료 박판 블레이드의 단면상수 계산 (Cross-sectional Constants of Thin-walled Composite Blades with Elliptical Profiles)

  • 박일주;이주영;정성남;신의섭
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2003년도 춘계학술발표대회 논문집
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    • pp.95-98
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    • 2003
  • In this work, a closed-form analysis is performed to obtain the stiffness coefficients of thin-walled composites beams with elliptical profiles. The analytical model includes the effects of elastic couplings, shell wall thickness, torsion warping and constrained warping. Reissner's semi-complementary energy functional is used to derive the beam force-displacement relations. The theory is validated against MSC/NASTRAN results for coupled composites beams with single-cell elliptical sections. Very good correlation has been noticed for the test cases considered.

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Influence of Surface Functional Group of Carbon Nanotubes for Applications in Electrochemical Capacitors

  • Park, Sul Ki
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.480.2-480.2
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    • 2014
  • Electrochemical capacitors have been the most strong energy storage devices due to high power density and long cycle stability. Pristine carbon nanotubes are promising electrode materials for excellent electrical conductivity and high specific surface area in electrochemical capacitor. However, the practical application of pristine carbon nanotubes was limited by the aggregation into bundles due to van der Waals force. In this research, we explained how multi-walled carbon nanotubes (MWCNT) functionalized by carboxyl, sulfonic, and amine groups (CNT-COOH, CNT-SO3H, CNT-NH2) to improve the performances of MWCNT. Functionalized CNTs showed two- to four-fold increase in capacitance over that of pristine CNTs, while maintaining reasonable cyclic stability. But, the CNT-COOH showed the lowest rate capability of 57% compared to 84%, 86% of CNT-SO3H and CNT-NH2. As demonstrated by the spectroscopic analysis, This reseach showed how surface functional group of carbon nanotubes change capacitor performances.

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Arthroscopic Partial Repair of Massive Contracted Rotator Cuff Tears

  • Kim, Sung-Jae;Kim, Young-Hwan;Chun, Yong-Min
    • Clinics in Shoulder and Elbow
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    • 제17권1호
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    • pp.44-47
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    • 2014
  • Typically, massive rotator cuff tears have stiff and retracted tendon with poor muscle quality, in such cases orthopaedic surgeons are confronted with big challenging to restore the cuff to its native footprint. Furthermore, even with some restoration of the footprint, it is related with a high re-tear rate due to less tension free repair and less tendon coverage. In this tough circumstance, the partial repair has yielded satisfactory outcomes at relatively short follow-up by re-creating the transverse force couple of the rotator cuff. Through this partial repair, the massive rotator cuff tear can be converted to the "functional rotator cuff tear" and provide improvement in pain and functional outcomes in patient's shoulder.

Advances in the Preparation of Soy Protein and Lecithin Ingredients for Tomorrow's Foods

  • Beery, Kenneth E.
    • 한국축산식품학회:학술대회논문집
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    • 한국축산식품학회 2002년도 정기총회 및 제29차 춘계국제 학술발표대회
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    • pp.29-38
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    • 2002
  • Today's food technologist is receiving increasingly pointed directions in the “selection of”and often “minimum amounts of”ingredients to use in the development of new food products. This increasing emphasis by marketing on “label”claims is real and gaining momentum in most market places. Thus, the development of functional foods that are providing customers with new and distinct nutritional choices. The driving force for the increased direction of the food technologist is that many governments are now allowing health related label claims on food products. These health claims are a result of very clearly and focused research that shows known nutritional benefits. The regulatory environment is well focused on the results of this peer reviewed research. In the USA, FDA has allowed several opportunities for health claims including fiber, soy protein and choline. This presentation will focus on only two of many functional ingredient options-the soy proteins and lecithin(choline).

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Influence of Surface Treatment of Polyimide Film on Adhesion Enhancement between Polyimide and Metal Films

  • Park, Soo-Jin;Lee, Eun-Jung;Kwon, Soo-Han
    • Bulletin of the Korean Chemical Society
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    • 제28권2호
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    • pp.188-192
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    • 2007
  • In this work, the effects of chemical treatment of polyimide films were studied by FT-IR, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and contact angles. The adhesion characteristics of the films were also investigated in the peel strengths of polyimide/aluminum films. The increases of surface functional groups of KOH-treated polyimide films were greatly correlated with the polar component of surface free energy. The peel strength of polyimides to metal substrate was also greatly enhanced by increasing the KOH treatment time, which can be attributed to the formation of polar functional groups on the polyimide surfaces, resulting in enhancement of the work of adhesion between polymer film and metal plate.

습식 표면개질 처리된 폴리이미드 필름 표면의 특성에 관한 연구 (A Study on Characteristics of Surface Modified Polyimide Film by Wet Process)

  • 구석본;이홍기
    • 한국표면공학회지
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    • 제39권4호
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    • pp.166-172
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    • 2006
  • Metallized Polyimide films are extensively used as base materials in microelectronics, optical and automotive applications. However it is difficult to deposit metals on those because of their structural stabilities. In this work, polyimide films are modified by a wet process with alkalinemetalhydroxide and additives to introduce functional groups. The surface molecular structures of polyimide are investigated using X-ray photoelectron spectroscopy(XPS), fourier transform infrared reflection spectroscopy(FTIR-ATR), atomic force micro-scopic(AFM). XPS spectra and FTIR spectra show that the surface structure of polyimide is converted into potassium polyamate. AFM image and AFM cross-sectional analyses reveal the increased roughness on the modified surface of polyimide films. As a result, it is shown that the adhesion strength between polyimide surface and electroless nickel layer is increased by the nano-anchoring effect.

Exploring Factors and Elements of Coordination between Key Account Management Units and Non-key Account Management Units: Case Study in an IT-related Machinery and System Vendor

  • Tonai, Shoko
    • Asia Marketing Journal
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    • 제18권1호
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    • pp.1-22
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    • 2016
  • Studies in key account management (KAM) have identified the importance of cross-functional coordination in firms to effectively implement KAM. However, these studies have ignored how companies integrate KAM and other customer management (non-KAM). This paper explores coordination design between KAM units and non-KAM units by analyzing a case study through three dimensions: front-end coordination, back-end-coordination, and organizational translation at the beginning of research. The case study shows that non-KAM conditions can require a modification of the coordination design. This research performs an in-depth analysis of changes in the implementation of sales reforms for an IT-related machinery and system vendor in Japan. Data sources include interviews with KAM units and non-KAM sales units and an analysis of secondary data. This paper suggests that studying the coordination between KAM units and non-KAM units will further our understanding of internal coordination in KAM research.

유한요소 해석을 통한 코트 스포츠화의 런닝시 충격력 평가 (Evaluation of Landing Impact Force of Court Sport Shoes at Running by Finite Element Analysis)

  • 김성호;조진래;류성헌;최주형
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.498-503
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    • 2004
  • A fundamental function of court sport shoes has been considered as the protection of human feet from unexpected injuries. But, recently its role for improving the playing competency is being regarded as a more important function. In connection with this situation, intensive efforts are being world-widely forced on the development of court sport shoes proving the excellent playing competency, by taking kinesiology and biomechanics into consideration. However, the success of this goal depends definitely on the shoes design based upon the reliable evaluation of shoes functional parts. This paper addresses the application of finite element method to the evaluation of landing impact force of court sport shoes. In order to reflect the coupling effect between leg and shoes accurately and effectively, we construct a fully coupled shoes-leg FEM model which does not rely on the independent experimental data any more. Through the numerical experiments, we assess the reliability of the coupled FEM model by comparing with the experimental results and investigate the landing impact characteristics of court sport shoes.

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인공디스크에 대한 생체역학적 분석 (Biomechanical Analysis of the Artificial Discs)

  • 김영은;윤상석;정상기
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.907-910
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    • 2005
  • Although several artificial disc designs have been developed for the treatment of discogenic low back pain, biomechanical change with its implantation was rarely studied. To evaluate the effect of artificial disc implantation on the biomechanics of functional spinal unit, nonlinear three-dimensional finite element model of L4-L5 was developed with 1-mm CT scan data. Two models implanted with artificial discs, SB $Charit\acute{e}$ or Prodisc, via anterior approach were also developed. The implanted model predictions were compared with that of intact model. Angular motion of vertebral body, force on spinal ligaments and facet joint, and the stress distribution of vertebral endplate for flexion-extension, lateral bending, and axial rotation with a compressive preload of 400 N were compared. The implanted model showed increased flexion-extension range of motion and increased force in the vertically oriented ligaments, such as ligamentum flavum, supraspinous ligament and interspinous ligament. The increase of facet contact force on extension were greater in implanted models. The incresed stress distribution on vertebral endplate for implanted cases indicated that additinal bone growth around vertebral body and this is matched well with clinical observation. With axial rotation moment, relatively less axial rotation were observed in SB $Charit\acute{e}$ model than in ProDisc model.

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모세관 리소그라피를 이용한 고종횡비 나노구조 형성법 (Capillary-driven Rigiflex Lithography for Fabricating High Aspect-Ratio Polymer Nanostructures)

  • 정훈의;이성훈;김필남;서갑양
    • 한국가시화정보학회지
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    • 제5권1호
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    • pp.3-8
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    • 2007
  • We present simple methods for fabricating high aspect-ratio polymer nanostructures on a solid substrate by rigiflex lithography with tailored capillarity and adhesive force. In the first method, a thin, thermoplastic polymer film was prepared by spin coating on a substrate and the temperature was raised above the polymer's glass transition temperature ($T_g$) while in conformal contact with a poly(urethane acrylate) (PUA) mold having nano-cavities. Consequently, capillarity forces the polymer film to rise into the void space of the mold, resulting in nanostructures with an aspect ratio of ${\sim}4$. In the second method, very high aspect-ratio (>20) nanohairs were fabricated by elongating the pre-formed nanostructures upon removal of the mold with the aid of tailored capillarity and adhesive force at the mold/polymer interface. Finally, these two methods were further used to fabricate micro/nano hierarchical structures by sequential application of the molding process for mimicking nature's functional surfaces such as a lotus leaf and gecko foot hairs.