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71.
Reduction of optical proximity effects (OPE), at deep uv wavelength of 248nm, caused by the variation of stepper lens operating conditions is investigated. It is shown that many of these effects, which increase as the Rayleigh limit is approached, can be minimised, and in many cases eliminated, by suitable choice of lens numerical aperture (NA) and partial coherence (sigma, σ).
Application of these results should enable the user of advanced wafer steppers to carry out high resolution lithography with a minimum of time consuming optical proximity correction (OPC). 相似文献
72.
Brendan McGrath 《Cities》1992,9(4)
Port Moresby is the capital of Papua New Guinea. With a population of nearly 200 000 it is by far the largest city in the country. Officially called the National Capital District (NCD), it straddles a low range of coastal hills in the south-east corner of the New Guinea mainland. It is a city facing serious problems today. A narrow economic base, a lack of land suitable for development and a deteriorating law and order situation are compounded by very rapid growth. The proposed construction of a transisland highway this decade, connecting Port Moresby to the populous interior, would have a profound impact on the future of the city. 相似文献
73.
74.
Testing of the multi-application small light water reactor (MASLWR) passive safety systems 总被引:1,自引:0,他引:1
Jose N. Reyes John Groome Brian G. Woods Eric Young Kent Abel You Yao Yeon Jong Yoo 《Nuclear Engineering and Design》2007,237(18):1999-2005
Experimental thermal hydraulic research has been conducted at Oregon State University for the purpose of assessing the performance of a new reactor design concept, the multi-application small light water reactor (MASLWR). The MASLWR is a pressurized light water reactor design with a net output of 35 MWe that uses natural circulation in both normal and transient operation. Due to its small size, portability and modularity, the MASLWR design is well suited to help fill the potential need for grid appropriate reactor designs for smaller electricity grids as may be found in developing or remote regions. The purpose of the OSU MASLWR test facility is to assess the operation of the MASLWR under normal full operating pressure and full temperature conditions and to assess the passive safety systems under transient conditions. The data generated by the testing program will be used to assess computer code calculations and to provide a better understanding of the thermal-hydraulic phenomena in the design of the MASLWR NSSS. During this testing program, four tests were conducted at the OSU MASLWR test facility. These tests included one design basis accident and one beyond design basis accident. During the performance of these tests, plant operations to include start up, normal operation and shut down evolutions were demonstrated successfully. 相似文献
75.
Brian Dipert 《电子设计技术》2005,12(11):72-72,74,76,78,80-81
顾客想要统一格式的蓝色激光存储器。但各竞争方无视这种需求,把不兼容的产品大量推向市场.进行一场高技术的赌博。 相似文献
76.
We propose an image hashing paradigm using visually significant feature points. The feature points should be largely invariant under perceptually insignificant distortions. To satisfy this, we propose an iterative feature detector to extract significant geometry preserving feature points. We apply probabilistic quantization on the derived features to introduce randomness, which, in turn, reduces vulnerability to adversarial attacks. The proposed hash algorithm withstands standard benchmark (e.g., Stirmark) attacks, including compression, geometric distortions of scaling and small-angle rotation, and common signal-processing operations. Content changing (malicious) manipulations of image data are also accurately detected. Detailed statistical analysis in the form of receiver operating characteristic (ROC) curves is presented and reveals the success of the proposed scheme in achieving perceptual robustness while avoiding misclassification. 相似文献
77.
78.
79.
J. L. Hedrick K. R. Carter H. J. Cha C. J. Hawker R. A. DiPietro J. W. Labadie R. D. Miller T. P. Russell M. I. Sanchez W. Volksen D. Y. Yoon David Mecerreyes R. Jerome James E. McGrath 《Reactive and Functional Polymers》1996,30(1-3):43-53
Foamed polyimides have been developed in order to obtain thin film dielectric layers with very low dielectric constants for use in microelectronic devices. In these systems the pore sizes are in the nanometer range, thus, the term ‘nanofoam’. The polyimide foams are prepared from block copolymers consisting of thermally stable and thermally labile blocks, the latter being the dispersed phase. Foam formation is effected by thermolysis of the thermally labile block, leaving pores of the size and shape corresponding to the initial copolymer morphology. Nanofoams prepared from a number of polyimides as matrix materials were investigated as well as from a number of thermally labile polymers. The foams were characterized by a variety of experiments including TEM, SAXS, WAXD, DMTA, density measurements, refractive index measurements and dielectric constant measurements. Thin film foams, with high thermal stability and low dielectric constants approaching 2.0, can be prepared using the copolymer/nanofoam approach. 相似文献
80.
Numerical study of steady turbulent flow through bifurcated nozzles in continuous casting 总被引:5,自引:0,他引:5
Fady M. Najjar Brian G. Thomas Donald E. Hershey 《Metallurgical and Materials Transactions B》1995,26(4):749-765
Bifurcated nozzles are used in continuous casting of molten steel, where they influence the quality of the cast steel slabs.
The present study performs two-dimensional (2-D) and three-dimensional (3-D) simulations of steady turbulent(K- ε) flow in bifurcated nozzles, using a finite-element (FIDAP) model, which has been verified previously with water model
experiments. The effects of nozzle design and casting process operating variables on the jet characteristics exiting the nozzle
are investigated. The nozzle design parameters studied include the shape, angle, height, width, and thickness of the ports
and the bottom geometry. The process operating practices include inlet velocity profile and angle as well as port curvature
caused by erosion or inclusion buildup. Results show that the jet angle is controlled mainly by the port angle but is steeper
with larger port area and thinner walls. The degree of swirl is increased by larger or rounder ports. The effective port area,
where there is no recirculation, is increased by smaller or curved ports. Flow asymmetry is more severe with skewed or angled
inlet conditions or unequal port sizes. Turbulence levels in the jet are higher with higher casting speed and smaller ports.
Formerly Research Assistant, Department of Mechanical and Industrial Engineering.
Formerly Research Assistant in the same department. 相似文献