Characterization of flexible transfer lines for liquid helium. New experimental results

The objective of this paper is to investigate the characterization of moisture diffusion inside early-age concrete slabs subjected to curing. Time-dependent relative humidity (RH) distributions of three mixture proportions subjected to three different curing methods (i.e., air curing, water curing, and membrane-forming compounds curing) and sealed condition were measured for 28 days. A one-dimensional nonlinear moisture diffusion partial differential equation (PDE) based on Fick’s second law, which incorporates the effect of curing in the Dirichlet boundary condition using a concept of curing factor, is developed to simulate the diffusion process. Model parameters are calibrated by a genetic algorithm (GA). Experimental results show that the RH reducing rate inside concrete under air curing is greater than the rates under membrane-forming compound curing and water curing. It is shown that the effect of water-to-cement (w/c) ratio on self-desiccation is significant. Lower w/c ratio tends to result in larger RH reduction. RH reduction considering both effect of diffusion and self-desiccation in early-age concrete is not sensitive to w/c ratio, but to curing method. Comparison between model simulation and experimental results indicates that the improved model is able to reflect the effect of curing on moisture diffusion in early-age concrete slabs.

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Experimental Study of Ductile Fracture for Non-Aligned Multiple Flaws in a Plate

Volume 1: Codes and Standards ◽

10.1115/pvp2009-77103 ◽

2009 ◽

Cited By ~ 3

Author(s):

Katsumasa Miyazaki ◽

Kunio Hasegawa ◽

Koichi Saito ◽

Bostjan Bezensek

Keyword(s):

Experimental Study ◽

Ductile Fracture ◽

Estimation Procedure ◽

Maximum Load ◽

Experimental Results ◽

Collapse Load ◽

Plate Specimen ◽

Fracture Tests ◽

Almost All

The fitness-for-service code requires the characterization of non-aligned multiple flaws for the flaw evaluation, which is performed using a flaw proximity rule. Worldwide almost all codes provide own proximity rule, often with unclear technical bases of the application of proximity rule to ductile fracture. To clarify the appropriate proximity rule for non-aligned multiple flaws in fully plastic fracture, fracture tests on flat plate specimen with non-aligned multiple through wall flaws were conducted at ambient temperature. The emphasis of this study was put on the flaw alignment rule, which determines whether non-aligned flaws are treated as independent or aligned onto the same plane for the purpose of flaw evaluations. The effects of the flaw separation and flaw size on the maximum load were investigated. The experimental results were compared with the estimations of the collapse load using the alignment rules in the ASME Section XI, BS7910 and API 579-1 codes. A new estimation procedure specific to the fully plastic fracture was proposed and compared with the comparison with the experimental results.

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Characterization of Maximum Current Capacity for Microprocessor Sockets

Advances in Electronic Packaging, Parts A, B, and C ◽

10.1115/ipack2005-73035 ◽

2005 ◽

Cited By ~ 1

Author(s):

David Song ◽

Ashish Gupta ◽

Chia-Pin Chiu

Keyword(s):

Risk Assessment ◽

Computational Modeling ◽

Carrying Capacity ◽

Infrared Camera ◽

Experimental Results ◽

Array Type ◽

Maximum Current ◽

Modeling And Experiments ◽

Subsequent Risk

This paper presents the current-carrying-capacity (CCC) characterization of a land-grid-array type microprocessor socket. This CCC study has been performed using both computational modeling and experiments using infrared camera. A subsequent risk assessment was performed against the maximum allowed temperature at the point of pressure contact of socket pin for the use-condition socket pin current and motherboard temperature. The results from the modeling and the experimental results are compared.

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Characterization of percolation behavior in conductor–dielectric 0-3 composites

Journal of Advanced Dielectrics ◽

10.1142/s2010135x14500350 ◽

2014 ◽

Vol 04 (04) ◽

pp. 1450035 ◽

Cited By ~ 9

Author(s):

Lin Zhang ◽

Patrick Bass ◽

Zhi-Min Dang ◽

Z.-Y. Cheng

Keyword(s):

Dielectric Constant ◽

Percolation Threshold ◽

Frequency Dependence ◽

Experimental Results ◽

Effective Dielectric Constant ◽

Filler Concentration ◽

Percolation Behavior ◽

The Matrix ◽

The Relationship

The equation ε eff ∝ (ϕc - ϕ)-s which shows the relationship between effective dielectric constant (εeff) and the filler concentration (φ), is widely used to determine the percolation behavior and obtain parameters, such as percolation threshold φc and the power constant s in conductor–dielectric composites (CDCs). Six different systems of CDCs were used to check the expression by fitting experimental results. It is found that the equation can fit the experimental results at any frequency. However, it is found that the fitting constants do not reflect the real percolation behavior of the composites. It is found that the dielectric constant is strongly dependent on the frequency, which is mainly due to the fact that the frequency dependence of the dielectric constant for the composites close to φc is almost independent of the matrix.

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