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排序方式: 共有1032条查询结果,搜索用时 15 毫秒
1.
Aishwarya
Srivastava Siddhant Aggarwal Amy Apon Edward Duffy Ken Kennedy Andre Luckow Brandon Posey Marcin Ziolkowski 《Software》2020,50(6):868-898
We investigate the challenges of building an end-to-end cloud pipeline for real-time intelligent visual inspection system for use in automotive manufacturing. Current methods of visual detection in automotive assembly are highly labor intensive, and thus prone to errors. An automated process is sought that can operate within the real-time constraints of the assembly line and can reduce errors. Components of the cloud pipeline include capture of a large set of high-definition images from a camera setup at the assembly location, transfer and storage of the images as needed, execution of object detection, and notification to a human operator when a fault is detected. The end-to-end execution must complete within a fixed time frame before the next car arrives in the assembly line. In this article, we report the design, development, and experimental evaluation of the tradeoffs of performance, accuracy, and scalability for a cloud system. 相似文献
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Artem Sokolov Darrell Whitley Andre’ da Motta Salles Barreto 《Genetic Programming and Evolvable Machines》2007,8(3):221-237
This paper evaluates different forms of rank-based selection that are used with genetic algorithms and genetic programming.
Many types of rank based selection have exactly the same expected value in terms of the sampling rate allocated to each member
of the population. However, the variance associated with that sampling rate can vary depending on how selection is implemented.
We examine two forms of tournament selection and compare these to linear rank-based selection using an explicit formula. Because
selective pressure has a direct impact on population diversity, we also examine the interaction between selective pressure
and different mutation strategies. 相似文献
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Motion Perception Using Analog VLSI 总被引:2,自引:0,他引:2
Andre J.S. Yakovleff Alireza Moini 《Analog Integrated Circuits and Signal Processing》1998,15(2):183-200
Motion perception is arguably a fundamental mechanism used by natural species to accomplish a number of tasks, such as navigating freely in an unknown environment. Traditional motion perception methods tend to be computationally intensive, requiring powerful computers and large memories. However, by copying biological mechanisms, such as elementary motion discrimination at the early stages of the visual processing paths, it should be possible to build small and efficient motion perception systems. This paper describes the manner in which a simple motion perception model based on the insect visual system has been implemented using mixed analog/digital VLSI. The device has been fabricated in a 2 micron double metal, double polysilicon process, and comprises 61 photo-detectors, and associated analog and digital circuitry. While not entirely successful in that component mismatches hamper the detection of dark-to-bright changes in contrast, the results clearly show the feasibility of using such a device in autonomous control systems. 相似文献
8.
Andre C.L. Carlin J.A. Boeckl J.J. Wilt D.M. Smith M.A. Pitera A.J. Lee M.L. Fitzgerald E.A. Ringel S.A. 《Electron Devices, IEEE Transactions on》2005,52(6):1055-1060
High-performance p/sup +//n GaAs solar cells were grown and processed on compositionally graded Ge-Si/sub 1-x/Ge/sub x/-Si (SiGe) substrates. Total area efficiencies of 18.1% under the AM1.5-G spectrum were measured for 0.0444 cm/sup 2/ solar cells. This high efficiency is attributed to the very high open-circuit voltages (980 mV (AM0) and 973 mV (AM1.5-G)) that were achieved by the reduction in threading dislocation density enabled by the SiGe buffers, and thus reduced carrier recombination losses. This is the highest independently confirmed efficiency and open-circuit voltage for a GaAs solar cell grown on a Si-based substrate to date. Larger area solar cells were also studied in order to examine the impact of device area on GaAs-on-SiGe solar cell performance; we found that an increase in device area from 0.36 to 4.0 cm/sup 2/ did not degrade the measured performance characteristics for cells processed on identical substrates. Moreover, the device performance uniformity for large area heteroepitaxial cells is consistent with that of homoepitaxial cells; thus, device growth and processing on SiGe substrates did not introduce added performance variations. These results demonstrate that using SiGe interlayers to produce "virtual" Ge substrates may provide a robust method for scaleable integration of high performance III-V photovoltaics devices with large area Si wafers. 相似文献
9.
F Brichory B Collet C Pineau B Desrues L Toujas JP Pennec L Dazord 《Canadian Metallurgical Quarterly》1996,11(3):148-152
This paper reports on the production of tumor necrosis factor (TNF) and granulocyte macrophage colony-stimulating factor (GM-CSF) by cultured mononuclear adherent cells derived from bone marrow of 25 patients affected by myelodysplastic syndrome (MDS) of different FAB subtypes. Mean production of GM-CSF was much lower than in controls, without significant differences among different subtypes. Mean production of TNF was similar in MDS patients and in controls, but noteworthy differences were observed between patients with RA, RAEB and RAEB-t and patients with RARS and CMML. Growth of bone marrow granulocyte macrophage and erythroid progenitors did not correlate with TNF and GM-CSF production, although in MDS subtypes with higher GM-CSF levels, colony growth was slightly higher than in subtypes with lower GM-CSF production. 相似文献
10.
]n recent years, hemodialysis treatment for chronic renal failure has been increasing. Although the technical evolutions have improved the therapy, the problem of microbial, toxic and chemical contamination of the dialysis fluid is now re-emerging. Most of all, because of increasing use of high-flux dialysis and its potential for transmembrane transport of bacteria into patients, one should be aware that dialysis fluid pathways may be colonised with bacteria. On the bacterial point of view, the French legislation proposed 100 CFU/mL as a maximum for total count of aerobic bacteria in the bi-osmosed water used for dilution of the dialysis concentrate. This study took place during 8 weeks in the children-hospital dialysis unit in Nancy (France). Our laboratory have succeeded in validating an aseptic bacteriological sampling procedure within fluid pathways of haemodialysis monitors Cobe CS3 and AK 100. It has also be shown that 6 to 12 hours of dialysis monitoring doesn't affect the quantitative and qualitative bacterial contamination of the biosmosed water (mean: 5 CFU/100 mL) drained through the 5 years' old internal pipes of the 2 monitors. So it has whatever the 4 different disinfection procedures applied and on the monitors (Formol or Formol + Citric acid + Chlorine or Heat or Heat + dehydrated Citric acid). 相似文献