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排序方式: 共有249条查询结果,搜索用时 15 毫秒
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Falco F Tamir T Leung KM 《Journal of the Optical Society of America. A, Optics, image science, and vision》2004,21(9):1621-1634
We address the problem of plane-wave scattering and Wood's anomalies at two-dimensional (2-D) periodic surfaces by employing a simplified grating model given by a planar surface whose impedance varies sinusoidally along two orthogonal directions. We obtain a rigorous solution to the corresponding boundary-value problem in terms of an infinite set of coupled recurrence equations. When truncated for computational purposes, this solution is in the form of a banded matrix, which we solve by direct methods and also by a highly efficient iterated matrix procedure. Numerical results are presented for symmetric and nonsymmetric incidence cases, and we show that certain diffracted fields do not depolarize in the former case. The expected Wood's anomalies of both Rayleigh and leaky-wave types are confirmed, and their location in wavelength space is numerically demonstrated for 2-D periodic configurations. 相似文献
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Karl Theodor Kriebel 《Remote sensing of environment》1978,7(1):81-83
The average variability of the reflected radiation field due to differing distributions of the irradiation in case of a savannah was given in a previous paper. In this paper, equivalent results are given for three more surfaces: bog, pasture land, and coniferous forest. Because the results are rather similar, mean values for vegetated surfaces can be derived. They indicate a change of the reflected radiance by per degree change of the solar zenith angle and per 10% change of the optical depth of the atmosphere. 相似文献
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Hoffmann M Küppers H Schneller T Böttger U Schnakenberg U Mokwa W Waser R 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2003,50(10):1240-1246
High piezoelectric coupling coefficients of PZT-based material systems can be employed for actuator functions in micro-electro-mechanical systems (MEMS) offering displacements and forces which outperform standard solutions. This paper presents simulation, fabrication, and development results of a stress-compensated, PZT-coated cantilever concept in which a silicon bulk micromachining process is used in combination with a chemical solution deposition (CSD) technique. Due to an analytical approach and a finite element method (FEM) simulation for a tip displacement of 10 /spl mu/m, the actuator was designed with a cantilever length of 300 /spl mu/m to 1000 /spl mu/m. Special attention was given to the Zr/Ti ratio of the PZT thin films to obtain a high piezoelectric coefficient. For first characterizations X-ray diffraction (XRD), scanning electron microscopy (SEM), hysteresis-, current-voltage I(V)and capacitance-voltage C(V)-measurements were carried out. 相似文献
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One of the most important problems when considering the design of manufacturing systems based on SOA paradigms is the integration of shop floor devices in the business processes at the enterprise level. This paper presents the design and implementation of the Customer Order Management (COM) module based on SOA architecture in the context of holonic manufacturing systems. The COM module is integrating with SOA enabled shop floor devices using industry standards. The implementation leverages a multi agent system suited for industrial applications integrated in a SOA environment capable of dynamic BPEL workflow generation and execution. The prototype consists in a SCA application for core COM module functionality and an extension for NetLogo MAS platform for SOA integration. The COM module interacts with the MES layer using real time events handled by the BPEL process implementation in the execution stage. A web based portal frontend for the COM module has been developed to allow real time tracking of customer orders, providing data about product batch execution and individual progress of each product on the production line. 相似文献
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Theodor Kellner 《Building Research & Information》2013,41(1-6):281-284
The combustibility ratings in different countries of steel skin panels with rigid polyurethane foam cores are outlined. The author then argues that, though such panels may be classified as combustible because of the core material, what matters is the actual fire behaviour of the sandwich panels in practice, illustrated by examples. The general conclusion is that the panels neither maintain nor spread fire. His paper is based on a report by the West German association for furthering the use of steel components in building, IVBS, of Dusseldorf — Industrie‐verband zur Förderung des Bauens mit Stahlblech. 相似文献
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Blast-resistant structural concrete and steel connections 总被引:1,自引:0,他引:1
A series of numerical studies were conducted on the behavior of structural concrete and structural steel connection subjected to blast loads. These studies gradually enhanced the understanding of the role that structural details play in affecting the behavior. Observations from those studies highlighted possible safety concerns with current blast design procedures. Conclusions and recommendations are provided for correcting the observed problems. 相似文献
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MS Binding Assays are a label‐free alternative to radioligand binding assays. They provide basically the same capabilities as the latter, but an unlabeled reporter ligand is used instead of a radioligand. The study presented herein describes the development of MS Binding Assays that address D1 and D5 dopamine receptors. A highly sensitive, rapid and robust LC–ESI‐MS/MS quantification method for the selective D1 dopamine receptor antagonist SCH23390 ((5R)‐8‐chloro‐3‐methyl‐5‐phenyl‐1,2,4,5‐tetrahydro‐3‐benzazepin‐7‐ol) was established and validated, using its 8‐bromo analogue SKF83566 as an internal standard. This quantification method proved to be suitable for the characterization of SCH23390 binding to human D1 and D5 receptors. Following the concept of MS Binding Assays, saturation experiments for D1 and D5 receptors were performed, as well as competition experiments for D1 receptors. The results obtained are in good agreement with results from radioligand binding assays and therefore indicate that the established MS Binding Assays addressing D1 and D5 receptors are well‐suited substitutes for radioligand binding assays, the technique that has so far dominated affinity determinations toward these targets. 相似文献