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51.
1Introduction Theultravioletrays(UV)insunlight(-4%)cantransmitintoroomthroughcommonfloatglass,theUVcanmakethematerialsintheroom,eg,paper,furni ture,textilefabricandplastics,becoloredanddeterio rated.ShieldingfromUVirradiationisofinterestinmanyfields.Formu…  相似文献   
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We present a discrete contour model for the segmentation of image data with any dimension of image domain and value range. The model consists of a representation using simplex meshes and a mechanical formulation of influences that drive an iterative segmentation. The object's representation as well as the influences are valid for any dimension of the image domain. The image influences introduced here, can combine information from independent channels of higher-dimensional value ranges. Additionally, the topology of the model automatically adapts to objects contained in images. Noncontextual tests have validated the ability of the model to reproducibly delineate synthetic objects. In particular, images with a signal to noise ratio of SNR /spl les/ 0.5 are delineated within two pixels of their ground truth contour. Contextual validations have shown the applicability of the model for medical image analysis in image domains of two, three, and four dimensions in single as well as multichannel value ranges.  相似文献   
54.
Columnar liquid crystals (LCs) are found to spontaneously form homeotropically‐aligned films when deposited on surfaces fabricated via friction transfer of polytetrafluoroethylene. The inside cover schematically shows the film structure of a phthalocyanine derivative together with the corresponding X‐ray diffraction pattern (inset). The results, reported on p. 815 by Dmitri Ivanov and co‐workers, indicate that not only are the columns homeotropically oriented but also that they form a single monodomain of macroscopic size. These findings can have an important impact for fabrication of LC‐based organic solar cells.  相似文献   
55.
The dependence between the activity parameters of muscarine antagonists in the prevention of haloperidol catalepsy in rats and those in tests characterizing the interaction of ligands and various subtypes of m-cholinoceptors was studied. It was established by constructing the mathematical dependence that blockade of m1-cholinoceptors increases, while that of m2-cholinoceptors reduces the antiparkinsonian activity of the drugs. The activity of the muscarine antagonist pentiphan in the prevention of haloperidol-induced catalepsy in rats exceeds the activity of such traditional antiparkinsonian drugs as cyclodol and amedin.  相似文献   
56.
30 patients were exposed to interference currents (IC) alone (group 1) versus 34 patients treated with IC plus iodobromine baths (group 2). After IC action on the region of the kidney projection patients of group 1 experienced positive changes in cellular and humoral immunity providing an antiinflammatory effect. In group 2, the improvement was seen in renal and urinary functions, 24-h urinary excretion of oxalates and calcium diminished. Interference current proved beneficial in chronic pyelonephritis patients with latent inflammation. The combined therapy was effective in patients at high risk of lithogenesis.  相似文献   
57.
An analog CMOS chip set for implementations of artificial neural networks (ANNs) has been fabricated and tested. The chip set consists of two cascadable chips: a neuron chip and a synapse chip. Neurons on the neuron chips can be interconnected at random via synapses on the synapse chips thus implementing an ANN with arbitrary topology. The neuron test chip contains an array of 4 neurons with well defined hyperbolic tangent activation functions which is implemented by using parasitic lateral bipolar transistors. The synapse test chip is a cascadable 4x4 matrix-vector multiplier with variable, 10-b resolution matrix elements. The propagation delay of the test chips was measured to 2.6 mus per layer.  相似文献   
58.
系统分析了微光探测器的结构及其原理。鉴于当前器件存在的激光致盲威胁,提出了新的改进思路。着重介绍了具有特殊激光防护性能的滤光材料,并对其原料及制备、加工过程作了系统地介绍,同时给出了一些重要的性能特征。  相似文献   
59.
Two‐component tensile bars with polyamide 6 (PA) and thermoplastic polyurethane (TPU) unmodified and modified with 4,4′‐diphenylmethane diisocyanate (MDI) have been investigated. It is known that the bond strength of PA/TPU tensile bars can increase by about 50% if MDI‐modified polyurethane is applied. The subject of these studies is the analysis of the influence of the mass temperatures on the bond strength. The mass temperatures of the first and second injection process and the delay time between the first and second injection processes determine the temperature gradient in the interface at the moment of the second injection. There is an increase in the bond strength when there is an increasing temperature gradient; therefore, the mass temperature of the first component at the delay time has to be lower than the mass temperature of the second component. The temperature gradient can be used as a measure of the thermal annealing of the first component near the interface during the heat transfer from the second component. It can be concluded that effective thermal annealing causes an increase in the bond strength. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4297–4305, 2006  相似文献   
60.
Based on a comprehensive analysis of findings from examination and surgical treatment of 196 patients with bleeding pyloroduodenal ulcers, it was found out that patients with concurrent helicobacteriosis of the stomach are prone to more unfavourable course of their illness, which fact is evidenced by a greater loss of blood and higher risk for bleeding recurrences. A classification is proposed by the authors, taking advantage of the data from endoscopic, microscopic and immunoenzymatic techniques, with the purpose of providing an assessment of degree of severity of helicobacteriosis of the stomach.  相似文献   
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