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排序方式: 共有312条查询结果,搜索用时 15 毫秒
31.
We investigate for the first time the possibility of integrating chemical vapor deposition (CVD) HfO/sub 2/ into the multiple gate dielectric system-on-a-chip (SoC) process in the range of 6-7 nm, which supports higher voltage (2.5-5 V operation/tolerance). Results show that CVD HfO/sub 2/-SiO/sub 2/ stacked gate dielectric (EOT =6.2 nm) exhibits lower leakage current than that of SiO/sub 2/ (EOT =5.7 nm) by a factor of /spl sim/10/sup 2/, with comparable interface quality (D/sub it//spl sim/1/spl times/10/sup 10/ cm/sup -2/eV/sup -1/). The presence of negative fixed charge is observed in the HfO/sub 2/-SiO/sub 2/ gate stack. In addition, the addition of HfO/sub 2/ on SiO/sub 2/ does not alter the dominant conduction mechanism of Fowler-Nordheim tunneling in the HfO/sub 2/-SiO/sub 2/ gate stack. Furthermore, the HfO/sub 2/-SiO/sub 2/ gate stack shows longer time to breakdown T/sub BD/ than SiO/sub 2/ under constant voltage stress. These results suggest that it may be feasible to use such a gate stack for higher voltage operation in SoC, provided other key requirements such as V/sub t/ stability (charge trapping under stress) can be met and the negative fixed charge eliminated. 相似文献
32.
Flavor perception and measurement play important roles in the development of food products. In an increasingly commercial environment, the food industry must strive to minimize adverse consumer reactions. This article gives an extensive overview on the various methods used for flavor measurement. Principles of flavor release and perception are discussed and applications to quality assessment are demonstrated. 相似文献
33.
JOE H. MIZE Fellow IIE Hemant C. Bhuskute Student Member IIE David B. Pratt Senior Member IIE Manjunath Kamath Associate Member IIE 《IIE Transactions》1992,24(3):14-26
Traditional approaches to the modeling of complex manufacturing systems are expensive, time consuming, and of limited value. Recent developments in several areas (i.e., knowledge engineering, software engineering, modeling formalisms, engineering workstations, and database systems) are now to the point that a meaningful convergence can be crafted to yield a modeling environment far superior to any we have known in the past. Fundamental to this new approach to modeling are the recent developments in object-oriented programming and related technologies. A research team at Oklahoma State University has been exploring alternative approaches to the modeling and simulation of complex manufacturing systems since 1985. This paper argues for a fundamental paradigm shift in the development and utilization of models within a CEM framework. 相似文献
35.
In this paper, we propose a double aperture double-gate AlGaN/GaN vertical high-electron-mobility transistor (HEMT) to improve the device characteristics, such as the current and the ON resistance (\(\hbox {\textit{R}}_{\mathrm{ON}}\)). The proposed vertical HEMT results are compared to the conventional single aperture single-gate vertical HEMT of equal dimensions, and increased drain current and lower \(\hbox {\textit{R}}_{\mathrm{ON}}\) are shown. A comprehensive simulation study has also been carried out for the proposed device, to analyse the impact of thickness and doping concentration of aperture, drift region, and current blocking layer. In addition, the effect of different materials in current blocking layer on device characteristics is also studied. The obtained results and their effect on device characteristics have been thoroughly analysed and explained accordingly. 相似文献
36.
One of the most desirable hair attributes to consumers, irrespective of ethnic background, is hair shine. The light reflected from a fiber has two components, specular and diffuse. The specular fraction of reflected light from the front surface of the fiber is generally recognized as a contributor to high luster. The distinction between specular and diffuse reflection is, however, not always clearly defined. In this study an attempt has been made to differentiate between specular and diffuse reflectance by analyzing mathematically goniophotometric curves of light reflected from unaltered single hair fibers from European, African, and Asian ethnic groups. The effect of macroscopic characteristics of the hair fibers, such as fiber diameter, cross-sectional shape, and curvature on luster is demonstrated. Results indicate that broadening of the specular peak reduces luster values, and is related to these characteristics. Thus, specular peak broadening is one of the important features to take into account when evaluating luster. Therefore, a new method for luster evaluation from goniophotometric curves is proposed. Additionally, we present the general model for light scattering, showing how scattering by surface roughness of different origin and magnitudes, and the scattering and absorption processes by the hair's interior, affect the position of the specular reflectance peak and its broadening. 相似文献
37.
S. Basavarajappa G. Chandramohan M. Prabu K. Mukund M. Ashwin 《International Journal of Machine Tools and Manufacture》2007,47(1):92-96
The main concern in the present study is the surface roughness variations on the drilled surface and extension of surface and sub-surface deformation due to drilling. The influence of different tools and cutting conditions on Al2219/15%SiCp and Al2219/15%SiCp-3%Graphite (hybrid) composites is investigated experimentally. The composites are fabricated by liquid metallurgy method. The drilling tests are conducted with carbide and coated carbide tools. The surface roughness decreases with the increase in cutting speed and increases with the increase in feed rate. The surface is analyzed using scanning electron microscope (SEM). Microhardness profiles indicate that the subsurface deformation extends up to a maximum of 120 μm below the machined surface for Al2219/15SiCp-3Gr composite when compared to 150 μm in Al2219/15SiCp composite. 相似文献
38.
Kamath R.R. Mansour-Cole D.M. Apana R. 《Engineering Management, IEEE Transactions on》1993,40(3):293-299
Existing knowledge about the correlates of innovation and the context of strategic decisions is used to develop propositions about the differences in the correlates of innovation in marketing and manufacturing functions. The theoretical model proposed is eclectic: it draws upon theory development in the fields of economics, engineering management, and corporate strategy. It is proposed that manufacturing managers link their innovation decisions to their assessment of the product's uniqueness in comparison with competitor's products. In contrast, marketing managers link their innovation decisions to the clarity of innovation objectives based on the customers' needs. The analysis of data from key informants in 172 firms is used to test the propositions. Whereas product uniqueness and clarity are significant correlates of innovation in the total sample, support is found for the proposition that the manufacturing subgroup focuses more on clarity 相似文献
39.
Patients with cirrhosis of the liver have increased hepatic and gastrointestinal lymph flow that may contribute to the formation of ascites and pleural effusions. Increased lymph flow, which is due to postsinusoidal portal hypertension, causes a high rate of flow through the thoracic duct. Because of the high flow rates, disrupted lymphatic vessels in patients with cirrhosis of the liver may fail to close, a situation that results in chylous ascites, pleural effusions, or chylous fistulas. Chylous fistulas deplete proteins, fluid, and lymphocytes and thus lead to volume depletion and coagulopathy. Herein we describe an unusual case in which a high-output traumatic thoracic duct-cutaneous fistula developed in a patient with cirrhosis and led to volume depletion and coagulopathy. Correction of the portal hypertension with placement of a transjugular intrahepatic portosystemic shunt led to closure of the fistula and normalization of accompanying metabolic abnormalities. 相似文献
40.
Adaptive-modulation schemes are designed that yield the minimum outage probability for wireless systems with strict delay constraints, under the assumption of perfect causal channel state information at the transmitter and receiver. Numerical results indicate that the proposed schemes significantly outperform adaptive schemes designed to maximize the average rate. 相似文献