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991.
In this paper, an evolutionary strategy approach is presented for tuning an AFLC to control the outlet temperature of a cooling coil. Two different methods, modifying scaling factors and modifying fuzzy membership functions, are studied. The simulation and real-time tests showed that evolutionary strategy techniques work well for evolving these AFLC parameters.  相似文献   
992.
Major U.S. cigarette companies for decades conducted research and development regarding cigarette ignition propensity which has continued beyond fire safety standards for cigarettes that have recently been legislated. This paper describes recent scientific advances and technological development based on a comprehensive review of the physical, chemical, and engineering sciences, public health, and trade literature, U.S. and international patents, and research in the tobacco industry document libraries. Advancements since the first implementation of standards have made been in: (a) understanding the key parameters involved in cigarette smoldering combustion and ignition of substrates; (b) developing new cigarette and paper wrapper designs to reduce ignition propensity, including banded and non-banded cigarette paper approaches, (c) assessing toxicology, and (d) measuring performance. While the implications of manufacturers’ non-safety-related aims are of concern, this research indicates possible alternative designs should experience with fire loss and existing technologies on the market suggest need for improvement.  相似文献   
993.
Soft rot disease of edible mushrooms leads to rapid degeneration of fungal tissue and thus severely affects farming productivity worldwide. The bacterial mushroom pathogen Burkholderia gladioli pv. agaricicola has been identified as the cause. Yet, little is known about the molecular basis of the infection, the spatial distribution and the biological role of antifungal agents and toxins involved in this infectious disease. We combine genome mining, metabolic profiling, MALDI-Imaging and UV Raman spectroscopy, to detect, identify and visualize a complex of chemical mediators and toxins produced by the pathogen during the infection process, including toxoflavin, caryoynencin, and sinapigladioside. Furthermore, targeted gene knockouts and in vitro assays link antifungal agents to prevalent symptoms of soft rot, mushroom browning, and impaired mycelium growth. Comparisons of related pathogenic, mutualistic and environmental Burkholderia spp. indicate that the arsenal of antifungal agents may have paved the way for ancestral bacteria to colonize niches where frequent, antagonistic interactions with fungi occur. Our findings not only demonstrate the power of label-free, in vivo detection of polyyne virulence factors by Raman imaging, but may also inspire new approaches to disease control.  相似文献   
994.
Silver nanorods have been grown by electrodeposition into thin film porous alumina templates (AAO). Optical transmission measurements using p‐polarized incident white light shows clear plasmon resonance extinction peaks. We successfully model the dependence on angle in incidence of extinction peak height and position using a multiple–multipoles (MMP) approach with the different spectral features being clearly associated with the effective electric field distribution and coupling between individual nanorods.  相似文献   
995.
Using a patented defect avoidance technique, high yield production of high density SRAM devices (ULSI SRAMs) can be achieved one process generation ahead of the rest of the industry. Production wafer yields as high as 100% and long-term average yields above 80% are reported on Inova's monolithic, 1.2μ, 320 square mm, one megabit SRAM demonstrating a practical method of achieving wafer scale integration. A yield model is presented and used to determine the optimized architecture and redundancy scheme for Inova's four megabit SRAM and to predict yield as a function of defect density. Achievement of a working 8M-bit experimental device using a 1.2μ process is also reported.  相似文献   
996.
Ron Wilson 《电子设计技术》2007,14(8):78-78,80,82,84
MOS图像传感器技术借鉴了CCD(电荷耦合器件)传感器的成功,为相机设计者打开了一片新的选择天地,尤其是在中档DSC(数码相机)和手机市场上.CCD工艺技术与CMOS逻辑工艺有很大差别,因此CCD的成像系统唯一可行的配置是使用一块独立传感器芯片,连接到一个单独的数字图像处理硬件上.  相似文献   
997.
最近常常在讨论齐纳二极管电压参考的作用与优势。尽管齐纳二极管是一种既稳定又精确的电压参考,但它们也要求高偏置电压(通常最小为8V)。这种高偏压要求将大多数齐纳二极管参考排除在源电压为5V(或更低)的电路以外。尽管能使用低偏压齐纳二极管,但其温飘会使其不能用于精密应用中。所有半导体结构都具有对温度敏感的基本电路,因此任何半导体参考都必须采用某种形式的内置温度补偿。齐纳二极管参考即采用内部串联二极管来进行温度补偿。基一射极偏差电压电路也具有同样的温飘问题和相应的解决方案,但由于其不依靠齐纳结,因此能在较低电压上工作。  相似文献   
998.
Lead halide perovskites are among the most exciting classes of optoelectronic materials due to their unique ability to form high-quality crystals with tunable bandgaps in the visible and near-infrared using simple solution precipitation reactions. This facile crystallization is driven by their ionic nature; just as with other salts, it is challenging to form amorphous halide perovskites, particularly in thin-film form where they can most easily be studied. Here, rapid desolvation promoted by the addition of acetate precursors is shown as a general method for making amorphous lead halide perovskite films with a wide variety of compositions, including those using common organic cations (methylammonium and formamidinium) and anions (bromide and iodide). By controlling the amount of acetate, it is possible to tune from fully crystalline to fully amorphous films, with an interesting intermediate state consisting of crystalline islands embedded in an amorphous matrix. The amorphous lead halide perovskite has a large and tunable optical bandgap. It improves the photoluminescence quantum yield and lifetime of incorporated crystalline perovskite, opening up the intriguing possibility of using amorphous perovskite as a passivating contact, as is currently done in record efficiency silicon solar cells.  相似文献   
999.
We present a new segmentation method for extracting thin structures embedded in three-dimensional medical images based on modern variational principles. We demonstrate the importance of the edge alignment and homogeneity terms in the segmentation of blood vessels and vascular trees. For that goal, the Chan-Vese minimal variance method is combined with the boundary alignment, and the geodesic active surface models. An efficient numerical scheme is proposed. In order to simultaneously detect a number of different objects in the image, a hierarchal approach is applied.  相似文献   
1000.
1D metal‐oxide nanostructures have attracted much attention because metal oxides are the most fascinating functional materials. The 1D morphologies can easily enhance the unique properties of the metal‐oxide nanostructures, which make them suitable for a wide variety of applications, including gas sensors, electrochromic devices, light‐emitting diodes, field emitters, supercapacitors, nanoelectronics, and nanogenerators. Therefore, much effort has been made to synthesize and characterize 1D metal‐oxide nanostructures in the forms of nanorods, nanowires, nanotubes, nanobelts, etc. Various physical and chemical deposition techniques and growth mechanisms are exploited and developed to control the morphology, identical shape, uniform size, perfect crystalline structure, defects, and homogenous stoichiometry of the 1D metal‐oxide nanostructures. Here a comprehensive review of recent developments in novel synthesis, exceptional characteristics, and prominent applications of one‐dimensional nanostructures of tungsten oxides, molybdenum oxides, tantalum oxides, vanadium oxides, niobium oxides, titanium oxides, nickel oxides, zinc oxides, bismuth oxides, and tin oxides is provided.  相似文献   
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