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1.
Kyle A. Crawford
Osama K. Eyada PhD PE
《Computers & Industrial Engineering》1989,17(1-4):298-302The worldwide proliferation of fraudulent materials has brought about the need for a new approach to the control of purchased material quality. Nuclear power, defense, aerospace and many other industries are affected by the supply of poor quality clones that presume to be original replacement parts. Safety considerations abound as these highly defective materials are used in systems that are critical to the preservation of human lives. Commonly utilized quality assurance programs have not effectively stopped the influx of fraudulent materials. These programs fail to concentrate inspection efforts on materials and inspection attributes that would effectively prevent the acceptance of fraudulent materials. herein a solution is presented to this problem in the form of an expert system application. Information commonly available in industry is formulated into a knowledge based system wherein advisories are given to the user regarding key purchased material receipt inspection strategies. 相似文献
2.
S. Kar T. Searles E. Lee G. B. Viswanathan H. L. Fraser J. Tiley R. Banerjee 《Metallurgical and Materials Transactions A》2006,37(3):559-566
The development of a set of computational tools that permit microstructurally based predictions for the tensile properties
of commercially important titanium alloys, such as Ti-6Al-4V, is a valuable step toward the accelerated maturation of materials.
This paper will discuss the development of neural network models based on a Bayesian framework to predict the yield and ultimate
tensile strengths of Ti-6Al-4V at room temperature. The development of such rules-based model requires the population of extensive
databases, which in the present case are microstructurally based. The steps involved in database development include producing
controlled variations of the microstructure using novel approaches to heat treatments, the use of standardized stereology
protocols to characterize and quantify microstructural features rapidly, and mechanical testing of the heat-treated specimens.
These databases have been used to train and test neural network models for prediction of tensile properties. In addition,
these models have been used to identify the influence of individual microstructural features on the tensile properties, consequently
guiding the efforts toward development of more robust mechanistically based models. Based on the neural network model, it
is possible to investigate the influence of individual microstructural features on the tensile properties, and in certain
cases these dependencies can point toward unrecognized phenomena. For example, the apparently unexpected trend of increase
in tensile strength with increasing prior β-grain size has led to the determination of the pronounced role of the basketweave microstructure in strengthening these alloys,
especially in case of larger prior β grains.
This article is based on a presentation made in the symposium “Computational Aspects of Mechanical Properties of Materials,”
which occurred at the 2005 TMS Annual Meeting, February 13–17, 2005, in San Francisco, CA, under the auspices of the MPMD-Computational
Materials Science & Engineering (Jt. ASM-MSCTS) Committee. 相似文献
3.
4.
There is a general impression in the literature that women are more accurate reporters of familial psychiatric history. In this regard, this study presents data from a large cohort of young men (n = 427) and women (n = 607) who in answering a questionnaire self-reported alcohol abuse symptoms for various biological relatives. No significant gender differences emerged for any of the family history comparisons including reports for father, mother, either parent, any first- or second-degree relatives, or men or women relatives. The findings are discussed in the context of the existing literature. 相似文献
5.
The Nelder-Mead simplex method is an optimization routine that works well with irregular objective functions. For a function of $n$ parameters, it compares the objective function at the $n+1$ vertices of a simplex and updates the worst vertex through simplex search steps. However, a standard serial implementation can be prohibitively expensive for optimizations over a large number of parameters. We describe an implementation of the Nelder-Mead method in parallel using a distributed memory. For $p$ processors, each processor is assigned $(n+1)/p$ vertices at each iteration. Each processor then updates its worst local vertices, communicates the results, and a new simplex is formed with the vertices from all processors. We also describe how the algorithm can be implemented with only two MPI commands. In simulations, our implementation exhibits large speedups and is scalable to large problem sizes. 相似文献
6.
Peter Potapov Matthew C. Hansen Stephen V. Stehman Thomas R. Loveland Kyle Pittman 《Remote sensing of environment》2008,112(9):3708-3719
Estimation of forest cover change is important for boreal forests, one of the most extensive forested biomes, due to its unique role in global timber stock, carbon sequestration and deposition, and high vulnerability to the effects of global climate change. We used time-series data from the MODerate Resolution Imaging Spectroradiometer (MODIS) to produce annual forest cover loss hotspot maps. These maps were used to assign all blocks (18.5 by 18.5 km) partitioning the boreal biome into strata of high, medium and low likelihood of forest cover loss. A stratified random sample of 118 blocks was interpreted for forest cover and forest cover loss using high spatial resolution Landsat imagery from 2000 and 2005. Area of forest cover gross loss from 2000 to 2005 within the boreal biome is estimated to be 1.63% (standard error 0.10%) of the total biome area, and represents a 4.02% reduction in year 2000 forest cover. The proportion of identified forest cover loss relative to regional forest area is much higher in North America than in Eurasia (5.63% to 3.00%). Of the total forest cover loss identified, 58.9% is attributable to wildfires. The MODIS pan-boreal change hotspot estimates reveal significant increases in forest cover loss due to wildfires in 2002 and 2003, with 2003 being the peak year of loss within the 5-year study period. Overall, the precision of the aggregate forest cover loss estimates derived from the Landsat data and the value of the MODIS-derived map displaying the spatial and temporal patterns of forest loss demonstrate the efficacy of this protocol for operational, cost-effective, and timely biome-wide monitoring of gross forest cover loss. 相似文献
7.
Manipulating Electrical and Fluidic Access in Integrated Nanopore‐Microfluidic Arrays Using Microvalves 下载免费PDF全文
8.
Georg Menge Hannes Lorenz Zongwen Fu Franziska Eichhorn Florian Schader Kyle G. Webber Tobias Fey Peter Greil Nahum Travitzky 《Advanced Engineering Materials》2018,20(7)
9.
Retracted: Dual Effects of Nanostructuring and Oxygen Vacancy on Photoelectrochemical Water Oxidation Activity of Superstructured and Defective Hematite Nanorods 下载免费PDF全文
Lei Wang Kyle Marcus Xiaojuan Huang Zhiqiang Shen Yang Yang Yingpu Bi 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(14)
An Ar atmospheric treatment is rationally used to etch and activate hematite nanoflakes (NFs) as photoanodes toward enhanced photoelectrochemical water oxidation. The formation of a highly ordered hematite nanorods (NRs) array containing a high density of oxygen vacancy is successfully prepared through in situ reduction of NFs in Ar atmosphere. Furthermore, a hematite (104) plane and an iron suboxide layer at the absorber/back‐contact interface are formed. The material defects produced by a thermal oxidation method can be critical for the morphology transformation from 2D NFs to 1D NRs. The resulting hematite NR photoanodes show high efficiency toward solar water splitting with improved light harvesting capabilities, leading to an enhanced photoresponse due to the artificially formed oxygen vacancies. 相似文献
10.
Péter Böröcz Csaba Pánczél Kyle Dunno S. Paul Singh 《Packaging Technology and Science》2023,36(1):45-53
This study investigates longitudinal acceleration events during freight transportation characterized as low-acceleration and long-duration using delivery van type vehicles. In the past several decades, there has been an increase in shipments requiring only single or small pallet load quantities and mixed palletized unit loads comprised of different goods. These loads are often transported in delivery vans without load securing devices, increasing the risk of product loss and damage due to load failures resulting from unit loads shifting. A field data acquisition system was used to observe and record the random acceleration events from five vehicles for 5 days, explicitly targeting the vehicles' braking and acceleration manoeuvres. The study aimed to understand the physical phenomenon and provide new information that can be used during preshipment tests to prevent damage to goods and ensure unit load integrity is maintained throughout the supply chain. The events were statistically analysed to understand their probability of occurrence, severity level, and quantify critical parameters such as event rise and hold times. For the braking manoeuvre, the statistical mean of average deceleration was 0.25 g with a corresponding rise and hold duration of 0.83 and 1.27 s, respectively. During the vehicle's acceleration manoeuvre, the statistical mean of average acceleration was 0.29 g with a rise and hold time of 1.29 and 1.39 s, respectively. Utilizing the field data, composite profiles were developed, and these profiles were compared to the currently available test procedures and previous results of other studies. 相似文献