• Title/Summary/Keyword: Contact Area

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Stabilization of Body Bias Control in SOI Devices by Adopting Si Film Island (SOI 소자에서의 바디 전압 안정화를 위한 실리콘 필름 Island 구조)

  • Chung, In-Young;Lee, Jong-Ho;Park, Young-June;Min, Hong-Shick
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.36D no.1
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    • pp.100-106
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    • 1999
  • A new IBC(Island Body Contact) structure is introduced to SOI CMOS VLSI for stabilizing the body potential of the MOSFET without the additional area consumption. The improvement of the body contact effect is achieved by reducing the body resistance and the area is saved as the bodies of the MOSFETs are connected together. Its property as VLSI device is confirmed through the device simulations and the measurement.

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Design of isolated footings of circular form using a new model

  • Rojas, Arnulfo Luevanos
    • Structural Engineering and Mechanics
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    • v.52 no.4
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    • pp.767-786
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    • 2014
  • This paper presents the design of reinforced concrete circular footings subjected to axial load and bending in two directions using a new model. The new model considers the soil real pressure acting on contact surface of the circular footings and these are different, with a linear variation in the contact area, these pressures are presented in terms of the axial load, moments around the axis "X" and the axis "Y". The classical model takes into account only the maximum pressure of the soil for design of footings and it is considered uniform at all points of contact area. Also, a comparison is presented in terms of the materials used (steel and concrete) between the two models shown in table, being greater the classical model with respect the new model. Therefore, the new model is the most appropriate, since it is more economic and also is adjusted to real conditions.

Development of Chemical Mechanical Polishing machine by Conical Drum (원뿔형 드럼을 이용한 화학기계적 연마기의 개발)

  • 서헌덕
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.10a
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    • pp.525-529
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    • 1999
  • A cone shape drum polisher was developed to make up for the demerits of conventional CMP apparatus. The developed equipment has several superiorities. First of all, it can achieve uniform velocity profile on all the contact line because of its shape and easy to control the amount of slurry at the position of use. The whole area of wafer surface is exposed to the visual area except the contact line between wafer and drum, hence we can detect polishing end point more easily than any other polishing equipments. Also it has additional merits such as small foot print and polishing load. Polishing characteristics were investigated by developed equipment.

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Mechanical properties on nanoindentation measurements of osteonic lamellae in a human cortical bone (나노인덴테이션을 이용한 인체 피질골 골층판의 물성연구)

  • Choi Hwan-Seok;Song Jung-Il;Joo Won-Kyung
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.527-528
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    • 2006
  • In the proposed research plan, the effects of anisotropic and time-dependent mechanical properties on nanoindentation measurements of osteonic lamellae in a human cortical bone are investigated. The most popular method(Oliver-Pharr method) in nanoindentation data analysis is based on the assumption of elastic isotropy. Since cortical bone has exhibited anisotropy, it is necessary to consider the effects of anisotropy on nanoindentation measurement for cortical bone. By comparison with the contact area obtained from monitoring the contact profile in FEA simulations, the Oliver-Pharr method was found to underpredict or overpredict the contact area due to effects of anisotropy. The mount of error depended on the indentation orientation. The indentation modulus results and were also similar to moduli calculated from mathematical model. The Oliver-Pharr method has been shown to be useful for providing first order approximations in analysis of anisotropic mechanical properties of cortical bone, although the indentation modulus is influenced by anisotropy.

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Rolling Wear Mechanism of Ceramics by SEM Observation (SEM 관찰에 의한 세라믹의 구름마모기구)

  • Kim, Seock-Sam;Kato, Kohji;Hokkirigawa, Kazuo
    • Tribology and Lubricants
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    • v.5 no.1
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    • pp.36-43
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    • 1989
  • Scanning electron microscopic observations were carried out on the worn surface and the wear debris of ceramic materials to investigate the wear mechanism of those in dry rolling contact. It was found from the scanning electron microscopic observations that the wear in ceramic materials is related to brittle fracture and has two types of wear mechanisms, small scale wear and larvae scare wear. Plate-like wear debris were created from the initial surface cracks and defects. The small scale wear was related to real contact area and large scale wear was related to HertzJan contact area. A wear model was proposed on the basis of scanning electron microscopic observations.

Fracture Mechanics Study on Wear Mechanism of Ceramics -Discussions on Experimental Results of Wear Test- (세라믹의 마멸기구에 관한 파괴역학적 연구 -마멸실험 결과의 고찰-)

  • 김석삼;김재호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.3
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    • pp.636-645
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    • 1990
  • Analytically induced wear mechanism of elastic body under Hertzian contact is applied in acutual wear test of ceramics. There are two types of wear in ceramics, a large scale wear and a small scale wear. The large scale wear is commensurable with Hertzian contact area and the small scale wear with real contact area. Nondimensional parameter, S$_{c}$, is introduced and fully examined to estimate or predict wear rate of ceramics. Ceramic wear for S$_{c}$.leq.0.8 is in small scale wear and for S$_{c}$;geq.1.6 in large scale wear. wear.

The Effect of Department Store CRM on Customer Satisfaction and Loyalty -Focused on clothing product customers in Deajeon area- (백화점 CRM이 고객만족과 고객충성에 미치는 영향 -대전지역 의류제품 고객을 중심으로-)

  • 박선희;박혜선
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.8
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    • pp.1186-1195
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    • 2004
  • The purposes of this study were to investigate the factors of CRM activity and the difference in CRM activities of department stores and to analyze the effect of CRM activities on customer satisfaction and loyalty. Investigators interviewed the buyers of three department stores in Daejeon area and surveyed 468 people aged over 20 who did shopping those stores. The data were analyzed with factorial analysis, multiple regression analysis, path analysis, ANOVA, Scheffe Test, etc., using the SPSS 10.0. The results of this study were: 1) Six factors were identified: 'benefit & information', 'service', 'customer invitation', 'customer contact', 'special management', and 'purchase-related help'; 2) CRM activities of three department stores were different, and department store buyers and customers were different in perception on CRM activities; and 3) Customer satisfaction was affected by the CRM factors like 'service', 'customer invitation', 'purchase-related help', 'benefit & information', and 'customer contact' Customer loyalty were affected directly by customer satisfaction, 'benefit & information' and 'service', and indirectly by 'customer invitation', 'purchase-related help', 'customer contact' through customer satisfaction.

A Study on the Mechanics of Shear Spinning of Cones

  • Kim Jae-Hun;Park Jun-Hong;Kim Chul
    • Journal of Mechanical Science and Technology
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    • v.20 no.6
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    • pp.806-818
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    • 2006
  • The shear spinning process, where the plastic deformation zone is localized in a very small portion of the workpiece, shows a promise for increasingly broader application to the production of axially symmetric parts. In this paper, the three components of working force are calculated by the newly proposed deformation model in which the spinning process is understood as shearing deformation after uniaxial yielding by bending, and shear stress, $\tau_{rz}$ becomes $\kappa$, yield limit in pure shear, in the deformation zone. The tangential forces are first calculated and the feed forces and the normal forces are obtained by the assumption of uniform distribution of roller pressure on the contact surface. The optimum contact area is obtained by minimizing the bending energy required to get the assumed deformation of the blank. The calculated forces are compared with experimental results. A comparison shows that theoretical prediction is reasonably in good agreement with experimental results.

Analysis Model of a Piezoelectric Transducer with Incomplete Contact (압전 변환기의 내부 불완전 접촉을 고려한 해석 모델)

  • Kim, Dae-Seung;Kim, Jin-Oh
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.864-868
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    • 2005
  • This paper develops an analysis model of a piezoelectric transducer. The transducer considered in this paper is a bolt-clamped Langevin-type transducer, which consists of a couple of piezoelectric discs, a couple of metal blocks for added mass effect, and a bolt to tighten them. A new analytical model for the transducer has been developed by taking into account the contact area between the piezoelectric ceramic and the metal block. The analysis model is verified by calculating the variations of the resonance frequency due to the contact area and comparing them with reported experimental results.

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Novel Wafer Warpage Measurement Method for 3D Stacked IC (3D 적층 IC제조를 위한 웨이퍼 휨 측정법)

  • Kim, Sungdong;Jung, Juhwan
    • Journal of the Semiconductor & Display Technology
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    • v.17 no.4
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    • pp.86-90
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    • 2018
  • Standards related to express the non-flatness of a wafer are reviewed and discussed, for example, bow, warp, and sori. Novel wafer warpage measurement method is proposed for 3D stacked IC application. The new way measures heat transfer from a heater to a wafer, which is a function of the contact area between these two surfaces and in turn, this contact area depends on the wafer warpage. Measurement options such as heating from room temperature and cooling from high temperature were experimentally examined. The heating method was found to be sensitive to environmental conditions. The cooling technique showed more robust and repeatable results and the further investigation for the optimal cooling condition is underway.