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801.
Poly (vinyl chloride), PVC, and poly(vinylidene fluoride), PVDF, are incompatible polymers. Poly(neopentyl glycol adipate), PDPA, is miscible with both PVC and PVDF. With PDPA acting as a compatibilizer between PVC and PVDF. compatible PVC/PDPA/PVDF blends can be formed at PVDF content of about less than 50wt%. Above 50wt% PVDF the ternary blends exist in two phases exhibiting two glass transition temperatures, Tg, PVC is the main contributor to the mechanical strength while PDPA and PVDF contribute to the elastic properties of these blends. A compatible blend of 55/22.5/22.5 wt% PVC/PDPA/PVDF exhibiting one single Tg appears to show an interesting balance of the properties of the blend components.  相似文献   
802.
803.
The aim of this study was to determine whether there are quantitative changes in the innervation of the anterior cruciate ligament in osteoarthritis. Eleven whole anterior cruciate ligaments were obtained at autopsy from cadavera of individuals with advanced osteoarthritis: five healthy ligaments were used as controls. The ligaments were transected and stained with hematoxylin and eosin, oil red O for fat, and a modification of Gairn's gold chloride method. The latter stain permits visualization of axons, mechanoreceptors, and free nerve endings that are not apparent on routine stains. The ratio of nerve tissue to periligamentous synovial tissue was determined histomorphometrically by the point-counting method. The nerve tissue was located almost exclusively in the periligamentous synovial tissue. There was a statistically significantly greater area of nerve tissue (as a percentage of the total area) around the anterior cruciate ligaments in the osteoarthritic group than around the ligaments in the control group (p < 0.02). The nerve tissue was distributed evenly throughout the periligamentous synovial tissue in the specimens in both groups. A neurological role has been proposed for the anterior cruciate ligament in osteoarthritis. This study provides morphological evidence for neural pathology of the anterior cruciate ligament in subjects with osteoarthritis.  相似文献   
804.
A semimicro modification of the Olsen method was developed to include nitratenitrogen in the total soil nitrogen determination by the standard semimicro-Kjeldahl method. The modified method was found to include nitrate-nitrogen effectively from standard nitrate solutions and soils. It was significantly superior to the commonly used salicylic acid method, which was found to give incomplete recovery of nitrate-nitrogen. In addition, changes in a number of experimental conditions such as amounts of water present and concentrated sulphuric acid used did not affect the results obtained by the modified Olsen method. In comparison with the recently recommended Raney catalysts for nitrate-nitrogen inclusion in the total nitrogen determination of fertilisers, preliminary results using standard nitrate solutions and following their additions to the soil indicate that reduced iron was comparable. Results obtained using glucose as a reducing agent in the standard semimicro-Kjeldahl method suggest that some nitratenitrogen was included by soil organic matter in the normal total soil nitrogen determination.  相似文献   
805.
Recent advances in evolutionary algorithms show that coevolutionary architectures are effective ways to broaden the use of traditional evolutionary algorithms. This paper presents a cooperative coevolutionary algorithm (CCEA) for multiobjective optimization, which applies the divide-and-conquer approach to decompose decision vectors into smaller components and evolves multiple solutions in the form of cooperative subpopulations. Incorporated with various features like archiving, dynamic sharing, and extending operator, the CCEA is capable of maintaining archive diversity in the evolution and distributing the solutions uniformly along the Pareto front. Exploiting the inherent parallelism of cooperative coevolution, the CCEA can be formulated into a distributed cooperative coevolutionary algorithm (DCCEA) suitable for concurrent processing that allows inter-communication of subpopulations residing in networked computers, and hence expedites the computational speed by sharing the workload among multiple computers. Simulation results show that the CCEA is competitive in finding the tradeoff solutions, and the DCCEA can effectively reduce the simulation runtime without sacrificing the performance of CCEA as the number of peers is increased.  相似文献   
806.
Caprari RS  Goh AS  Moffatt EK 《Applied optics》2000,39(35):6633-6640
We present a Wiener filter that is especially suitable for speckle and noise reduction in multilook synthetic aperture radar (SAR) imagery. The proposed filter is nonparametric, not being based on parametrized analytical models of signal statistics. Instead, the Wiener-Hopf equation is expressed entirely in terms of observed signal statistics, with no reference to the possibly unobservable pure signal and noise. This Wiener filter is simple in concept and implementation, exactly minimum mean-square error, and directly applicable to signal-dependent and multiplicative noise. We demonstrate the filtering of a genuine two-look SAR image and show how a nonnegatively constrained version of the filter substantially reduces ringing.  相似文献   
807.
The effects of rehearsing actions by source (slideshow vs. story) and of test modality (picture vs. verbal) on source monitoring were examined. Seven- to 8-year-old children (N = 30) saw a slideshow event and heard a story about a similar event. One to 2 days later, they recalled the events by source (source recall), recalled the events without reference to source (no-source-cue recall), or engaged in no recall. Seven to 8 days later, all children received verbal and picture source-monitoring tests. Children in the source recall group were less likely than children in the other groups to claim they saw actions merely heard in the story. No-source-cue recall impaired source identification of story actions. The picture test enhanced recognition, but not source monitoring, of slide actions. Increasing the distinctiveness of the target events (Experiment 2) allowed the picture test to facilitate slideshow action discrimination by children in the no-recall group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
808.
International Journal of Wireless Information Networks - Prior to the 21st century, positioning technologies had limited applications including air traffic control, air and sea navigation,...  相似文献   
809.
The cumulative count of conforming (CCC) chart is a new type of control chart used for the monitoring of high-quality processes. Instead of counting the number of non-conforming items in samples of fixed size, the cumulative number of conforming items between two non-conforming items is monitored. The CCC chart is convenient to use in a modern manufacturing environment where the product is inspected individually and automatically. The CCC chart has sometimes been confused with the cumulative sum (CUSUM) chart which has been shown to be more sensitive than the traditional Shewhart chart for small process shifts. In this paper the uses of these two types of charts are compared. It shown by numerical illustrations and analytical results that the two charts function in entirely different ways. However, the CUSUM concept can be applied to cumulative counts used in the CCC chart to improve its sensitivity for small process shifts when the process is producing at a very low non-conforming rate. © 1998 John Wiley & Sons, Ltd.  相似文献   
810.
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