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51.
This paper describes the implementation of a stereo-vision system using Field Programmable Gate Arrays (FPGAs). Reconfigurable hardware, including FPGAs, is an attractive platform for implementing vision algorithms due to its ability to exploit parallelism often found in these algorithms, and due to the speed with which applications can be developed as compared to hardware. The system outputs 8-bit, subpixel disparity estimates for 256× 360 pixel images at 30,fps. A local-weighted phase correlation algorithm for stereo disparity [Fleet, D. J.: {Int. Conf. Syst. Man Cybernetics 1:48–54 (1994)] is implemented. Despite the complexity of performing correlations on multiscale, multiorientation phase data, the system runs as much as 300 times faster in hardware than its software implementation. This paper describes the hardware platform used, the algorithm, and the issues encountered during its hardware implementation. Of particular interest is the implementation of multiscale, steerable filters, which are widely used in computer vision algorithms. Several trade-offs (reducing the number of filter orientations from three to two, using fixed-point computation, changing the location of one localized low-pass filter, and using L1 instead of L2 norms) were required to both fit the design into the available hardware and to achieve video-rate processing. Finally, results from the system are given both for synthetic data sets as well as several standard stereo-pair test images. 相似文献
52.
Kittisak Jantanasakulwong Sarinthip Thanakkasaranee Phisit Seesuriyachan Pisith Singjai Aphisit Saenjaiban Siriphan Photphroet Kanticha Pratinthong Yuthana Phimolsiripol Noppol Leksawasdi Thanongsak Chaiyaso Sarana Rose Sommano Pensak Jantrawut Siriwadee Chomdej Suwit Chotinan Francisco J. Barba Joe M. Regenstein Alissara Reungsang Pornchai Rachtanapun 《International journal of molecular sciences》2022,23(18)
The nano-metal-treated PET films with anti-virus and anti-fogging ability were developed using sparking nano-metal particles of Ag, Zn, and Ti wires on polyethylene terephthalate (PET) films. Ag nanoparticles were detected on the PET surface, while a continuous aggregate morphology was observed with Zn and Ti sparking. The color of the Ag-PET films changed to brown with increasing repeat sparking times, but not with the Zn-PET and Ti-PET films. The water contact angle of the nano-metal-treated PET films decreased with increasing repeat sparking times. The RT-PCR anti-virus test confirmed the high anti-virus efficiency of the nano-metal-treated PET films due to the fine particle distribution, high polarity, and binding of the nano-metal ions to the coronavirus, which was destroyed by heat after UV irradiation. A highly transparent, anti-fogging, and anti-virus face shield was prepared using the Zn-PET film. Sparking was an effective technique to prepare the alternative anti-virus and anti-fogging films for medical biomaterial applications because of their low cost, convenience, and fast processing. 相似文献
53.
Aldo M. Crugnola Eric L. Radin Robert M. Rose Igor L. Paul Sheldon R. Simon Mark B. Berry 《应用聚合物科学杂志》1976,20(3):809-812
Currently there is widespread use of ultrahigh molecular weight polyethylene (UHMWPE) acetabular components in total joint replacement prostheses. What has been most surprising about the wear of UHMWPE under such circumstances is the occurrence of brittle fracture. Such fracture had not been observed in the usual engineering tests done in the laboratory on UHMWPE. It was only when prosthese which had been removed from patients were examined or run in hip joint simulators with serum or synovial fluid as the lubricant, that brittle fracture was encountered. The problem of environment-enhanced brittle fracture in plastics dates back to 1946. Interestingly, the phenomenon was first described in polyethylene. The prime variables involved are polymer molecular weight, sensitizing environment, stress filed, and temperature. Other things being equal, brittle behavior in polyethylene is extremely sensitive to the amount of low molecular weight polymer present. In the light of the foregoing we have studied the molecular weight distribution in six commercially available UHMWPE components. These were obtained from six different manufacturers. The specimens were characterized both on their bearing (wear) surfaces and in their interior bulk. The results obtained indicate that:
- 1 The UHMWPE components contain substantial amounts of low molecular weight polymer.
- 2 The UHMWPE components differ significantly in molecular weight distribution.
- 3 The UHMWPE components contain substantial amounts of crosslinked polymer.
54.
Martin Oschatz Marcus Rose Nicole Klein Thomas Freudenberg Gleb Yushin 《Carbon》2010,48(14):3987-3992
A hierarchical and highly porous carbide-derived carbon (CDC) was obtained by nanocasting of pre-ceramic precursors into cubic ordered silica (KIT-6) and subsequent chlorination. Resulting CDC replica materials show high methane and n-butane uptake and excellent performance as electrode materials in supercapacitors. 相似文献
55.
The objective was to relate the short-term milk yield response (MYR) following use of exogenous bovine somatotropin (bST) to changes in plasma concentrations of metabolites and hormones. Twenty-four Holstein cows (52 +/- 4.1 d postpartum) received daily subcutaneous injections of saline for 1 wk followed by subcutaneous injections of 33 mg/d of bST for 2 wk (Trial 1). The difference in milk yield between wk 1 and 3 for each cow was used to determine the 5 cows with the highest (HR) and 5 with the lowest responses (LR) to bST. These 10 cows were then used in 3 further trials of the same design (Trials 2, 3, and 4, conducted at 122, 181, and 237 +/- 7.6 d postpartum, respectively). Blood samples were taken 2 h after the administration of bST on d 1, 3, 5, 15, 17, and 19 of each trial. The HR group had consistently greater MYR to bST than the LR group throughout their lactation. The LR group had a higher milk yield and lower plasma insulin like growth factor-I (IGF-I) concentrations during the saline treatment in all trials. The increase in plasma somatotropin concentrations following injections of bST was greater for the LR group, whereas the difference in plasma IGF-I level between wk 1 and 3 was greater for the HR group. The HR group had lower levels of 3-hydroxy-butyrate and nonesterified fatty acids before bST treatment. Low short-term response to bST was associated with plasma concentrations of hormones and metabolites that indicate negative energy balance, although other factors may be involved. 相似文献
56.
Lisa J. White Giles T.S. Kirby Helen C. Cox Roozbeh Qodratnama Omar Qutachi Felicity R.A.J. Rose Kevin M. Shakesheff 《Materials science & engineering. C, Materials for biological applications》2013,33(5):2578-2583
There is a need to control the spatio-temporal release kinetics of growth factors in order to mitigate current usage of high doses. A novel delivery system, capable of providing both structural support and controlled release kinetics, has been developed from PLGA microparticles. The inclusion of a hydrophilic PLGA–PEG–PLGA triblock copolymer altered release kinetics such that they were decoupled from polymer degradation. A quasi zero order release profile over four weeks was produced using 10% w/w PLGA–PEG–PLGA with 50:50 PLGA whereas complete and sustained release was achieved over ten days using 30% w/w PLGA–PEG–PLGA with 85:15 PLGA and over four days using 30% w/w PLGA–PEG–PLGA with 50:50 PLGA. These three formulations are promising candidates for delivery of growth factors such as BMP-2, PDGF and VEGF. Release profiles were also modified by mixing microparticles of two different formulations providing another route, not previously reported, for controlling release kinetics. This system provides customisable, localised and controlled delivery with adjustable release profiles, which will improve the efficacy and safety of recombinant growth factor delivery. 相似文献
57.
Ifechukwu E. Adieze Justina C. Orji Rose N. Nwabueze G.O.C. Onyeze 《The International journal of environmental studies》2013,70(3):490-500
Responses to hydrocarbon stress of four tropical plants Panicum maximum, Zea mays, Centrosema sp. and Pueraria sp. grown in crude oil contaminated soils (1%, 5% and 10% w/w) were evaluated in a green house. Plants’ percentage survival, shoot heights, biomass development, and phytotoxicity susceptibility were used as indicators of growth, stress response and hydrocarbon tolerance. Relative to control, shoot heights and biomass of plants reduced with increasing hydrocarbon concentration, but 1% w/w oil-in-soil, stimulated shoot heights (5.9% and 6.4%) and weights (21.9% and 2.3%) in P. maximum and Centrosema sp. respectively. P. maximum tolerated the contaminant stress with biomass yields of 113% and 57% of control respectively in 1% and 10% w/w oil-in-soil. All the plants had 100% survival in 1% w/w, but considerably reduced survival in 10% w/w oil-in-soil. These results show that P. maximum has great potential for phytoremediation of petroleum contaminated soil. 相似文献
58.
59.
Television is not only the most powerful medium of communication that our age has produced; it is also the most flexible. Yet its common role in education is that of a mere substitute, called in to mitigate the effects of the shortage of teachers or (to look at the matter historically) the excess of students. That it can be more than that is shown by two University of Nebraska faculty members, describing an experiment in the creative use of television as a tool in the development of that awareness of the characteristics of space which is among the architect's indispensable qualifications. 相似文献
60.
Fabrication of high aspect ratio and open‐ended TiO2 nanotube photocatalytic arrays through electrochemical anodization 下载免费PDF全文
Roong Jien Wong Sanly Liu Yun Hau Ng Rose Amal 《American Institute of Chemical Engineers》2016,62(2):415-420
Well‐aligned, high aspect‐ratio and open‐ended TiO2 nanotube arrays secured within a Ti foil (TiO2 nanotubes cartridge) were successfully prepared through the double‐sided anodization method. With ~210 µm of nanotube length, the anodic growth of TiO2 was accelerated and stabilized by the lactic acid‐containing ethylene glycol electrolyte. In the absence of lactic acid, the anodization led to detachment of nanotubes from the Ti foil after 5–6 h of high voltage (80 V) anodization. Transmission electron microscope image and Raman spectrum revealed that the as‐anodized TiO2 nanotube arrays without annealing treatment were partially crystalline anatase and demonstrated photocatalytic activity in the mineralization of formic acid. © 2015 American Institute of Chemical Engineers AIChE J, 62: 415–420, 2016 相似文献