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951.
This is the second in a series of two papers generated from a study on probabilistic meshless analysis of cracks. In this
paper, a stochastic meshless method is presented for probabilistic fracture-mechanics analysis of linear-elastic cracked structures.
The method involves an element-free Galerkin method for calculating fracture response characteristics; statistical models
of uncertainties in load, material properties, and crack geometry; and the first-order reliability method for predicting probabilistic
fracture response and reliability of cracked structures. The sensitivity of fracture parameters with respect to crack size,
required for probabilistic analysis, is calculated using a virtual crack extension technique described in the companion paper
[1]. Numerical examples based on mode-I and mixed-mode problems are presented to illustrate the proposed method. The results
show that the predicted probability of fracture initiation based on the proposed formulation of the sensitivity of fracture
parameter is accurate in comparison with the Monte Carlo simulation results. Since all gradients are calculated analytically,
reliability analysis of cracks can be performed efficiently using meshless methods.
Received 20 February 2001 / Accepted 19 December 2001 相似文献
952.
Of the 378 cases of stage 3 carcinoma uterine cervix, only 10 showed vesical invasion, while 19 of 24 cases of stage 4 disease had vesical invasion. Results of this procedure did not alter the management of the disease in any of these cases. From the whole series it was concluded that cysto-urethroscopy is an unnecessary, cost ineffective, invasive procedure which has no role in either diagnosis or in planning the definitive treatment of carcinoma uterine cervix. 相似文献
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955.
McCall J.C. Wipf D.P. Trivedi M.M. Rao B.D. 《Intelligent Transportation Systems, IEEE Transactions on》2007,8(3):431-440
In this paper, we demonstrate a driver intent inference system that is based on lane positional information, vehicle parameters, and driver head motion. We present robust computer vision methods for identifying and tracking freeway lanes and driver head motion. These algorithms are then applied and evaluated on real-world data that are collected in a modular intelligent vehicle test bed. Analysis of the data for lane change intent is performed using a sparse Bayesian learning methodology. Finally, the system as a whole is evaluated using a novel metric and real-world data of vehicle parameters, lane position, and driver head motion. 相似文献
956.
The stability behaviour of columns, subjected to a uniformly distributed axial load and with one end elastically restrained to move axially, is studied in this paper. The elastic axial restraint is represented by means of an axial spring. The finite element formulation, including prebuckling load analysis and stability analysis, is briefly described. Numerical results in terms of stability parameter for various values of axial spring stiffness parameter for four types of boundary conditions are obtained. Stability mode shapes for three specific values of axial spring stiffness parameter are given. 相似文献
957.
Subramani Saravanabhavan Jonnalagadda Raghava Rao Balachandran Unni Nair Thirumalachari Ramasami 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2007,82(11):971-984
BACKGROUND: The leather industry is under pressure to develop environmentally efficient leather‐making processes to comply with modern pollution and discharge legislation. Conventional leather‐processing methods are known to contribute significant pollution loads in tannery wastewaters. The rationalized process described here involves a salt‐free curing, lime and sulfide‐free beamhouse process and post‐tanning followed by tanning employing a reverse leather‐processing technique. RESULTS: Scanning electron microscopy (SEM) analysis substantiated that the grain surface, fibre separation and tight packing of fibres are similar for leathers from conventional and rationalized processes. The functional performance of the leathers is found to be on par with that of conventionally processed leathers. The rationalized leather process reduces the usage and discharge of chemicals by 68% and 82%, respectively. It also enjoys the reduction in biochemical oxygen demand (BOD), chemical oxygen demand, Cl?, SO42? and total solids loads by 58%, 62%, 95%, 66% and 85%, respectively. The rationalized process also results in reduction of water consumption and discharge and energy by 37%, 37% and 38%, respectively. CONCLUSION: The rationalized process utilizes resources efficiently with reduced environmental impact without compromising leather qualities and can be seen as being eco‐efficient compared to the conventional leather process. Copyright © 2007 Society of Chemical Industry 相似文献
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The purpose of the present theoretical analysis is to provide explicit solutions for the problem of condensation of vapours on the lateral surface of a long vertical plate fin of variable cross-section. The formulation yields solutions to the Limiting cases so that the results can be employed in the design of the condenser section of a flat plate heat pipe in which the fin is considered to be an essential element in transporting heat liberated by the condensing vapours. It is observed that the local and average Nusselt numbers depend on fin parameter, fin profile index, Rayleigh number and degree of subcooling. 相似文献
960.