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991.
无论全球化如何发展,固有的文化认同仍然存在,这也对电器的个性化提出了更高的要求。随着城市化的不断发展,城市文化逐渐生根。我们开始以相同的方式生活、工作和游戏。对于电器营销人员来说, 相似文献
992.
Bhaskar Chatterjee 《Microelectronics Journal》2005,36(9):801-809
In this paper, we discuss the design of leakage tolerant wide-OR domino gates for deep submicron (DSM), bulk CMOS technologies. Technology scaling is resulting in a 3×-5× increase in transistor IOFF/μm per generation causing 15-30% degradation in the noise margin of high performance domino gates. We investigate several techniques that can improve the noise margin of domino logic gates and thereby ensure their reliable operation for sub-130 nm technologies. Our results indicate that, selective usage of dual VTH transistors shows acceptable energy-delay tradeoffs for the 90 nm technology. However, techniques like supply voltage (Vcc) reduction or using non-minimum Le transistors are required in order to ensure robust and low power operation of wide-OR domino designs for the 70 nm generation. 相似文献
993.
M. Ghosh Samar Das P.S. Banarjee S. Chatterjee 《Materials Science and Engineering: A》2005,390(1-2):217-226
Solid state bonding was carried out between commercially pure titanium and 304 stainless steel at 850 °C temperature for 30–150 min under uniaxial load in vacuum. The transition joints were characterized using optical and scanning electron microscopes and revealed the presence of reaction layers in the diffusion zone. The chemical composition of these reaction products was determined by energy dispersive spectroscopy and the presence of phase/phase mixtures σ, -Fe + χ, χ + λ, λ + FeTi + β-Ti and β-Ti were predicted. Their existence was also confirmed by X-ray diffraction technique. The concentration–penetration plots for Ti, Fe, Cr and Ni are obtained from electron probe microanalysis, which also exhibit concentration gaps in the profile indicating formation of intermetallics in the diffusion zone. The width of intermetallic phases attains its maximum for 90 min joining time, then drops and again rises for 150 min bonding time. The maximum bond strength of 76% of that of titanium was achieved for the assemblies processed for 90 min owing to better coalescence of the mating surfaces, though the volume fraction of intermetallics is high. 相似文献
994.
ARC: an integrated admission and rate control framework for competitive wireless CDMA data networks using noncooperative games 总被引:3,自引:0,他引:3
The competition among wireless data service providers brings in an option for the unsatisfied customers to switch their providers, which is called churning. The implementation of Wireless Local Number Portability (WLNP) is expected to further increase the churn rate (the probability of users switching the provider). However, the existing resource management algorithms for wireless networks fail to fully capture the far-reaching impact of this unforeseen competitiveness. From this perspective, we first formulate noncooperative games between the service providers and the users. A user's decision to leave or join a provider is based on a finite set of strategies. A service provider can also construct its game strategy set so as to maximize their utility (revenue) considering the churn rate. Based on the game theoretic framework, we propose an integrated admission and rate control (ARC) framework for CDMA-based wireless data networks. The admission control is at the session (macro) level while the rate control is at the link layer packet (micro) level. Two admission control modes are considered - one-by-one mode and batch processing mode, in which multiple users are admitted at a time. We show that: 1) for the one-by-one mode, the Nash equilibrium using pure strategy can be established for both under-loaded and fully-loaded systems and 2) for batch processing mode, there is either an equilibrium in pure strategy or a dominant strategy exists for the service provider. Therefore, the providers have clearly defined admission criteria as outcome of the game. Users are categorized into multiple classes and offered differentiated services based on the price they pay and the service degradation they can tolerate. We show that the proposed ARC framework significantly increases the provider's revenue and also successfully offers differentiated QoS to the users. 相似文献
995.
An adaptive quasi-Newton algorithm for eigensubspace estimation 总被引:1,自引:0,他引:1
Zhengjiu Kang Chatterjee C. Roychowdhury V.P. 《Signal Processing, IEEE Transactions on》2000,48(12):3328-3333
We derive and discuss a new adaptive quasi-Newton eigen-estimation algorithm and compare it with the RLS-type adaptive algorithms and the quasi-Newton algorithm proposed by Mathew et al. (1995) through experiments with stationary and nonstationary data. 相似文献
996.
Sharmistha Sinha Shruti S. Bandyopadhyay Debjani Ghosh Udipta Ranjan Chatterjee Sudipta Saha Pradyot K. Ghosal Bimalendu Ray 《Food science and biotechnology》2011,20(4):1005-1011
Senna (Cassia angustifolia) is widely used in Indian folk medicine for the prevention of various disorders. Herein, we have demonstrated that water
extracted arabinogalactan protein (AGP) rich fraction possesses strong antioxidative activity. The AGP rich fraction was analyzed
using chemical, chromatographic, and spectroscopic methods. Effect of water extracted polymers on bovine serum albumin spectrum
was determined using excitation wavelength of 282 nm. The antioxidant capacity of this fraction was studied by ferric reducing
antioxidant power (FRAP) and DPPH radical assays. This polymeric fraction, ≥88% of which gets precipitated with Yariv reagent,
consisted mainly of (1→5)-/(1→3,5)-linked α-arabinosyl, (1→3)-/(1→3,6)-linked-galactosyl residues and terminal arabinofuranosyl
residues. Its in vitro antioxidant capacity is comparable to that of standard antioxidants. Fluorescence quenching studies furnishes evidence for
the interaction of the arabinogalactan protein with bovine serum albumin. 相似文献
997.
NaA zeolite nanoparticles (seed crystals) of size 50–65 nm were synthesized using water-in-oil (w/o) type emulsions at a considerably
low temperature of 65 ± 1°C in a short duration of 2 h. The emulsions were stabilized using non-ionic surfactants e.g. sorbitan
monooleate (Span 80), sorbitan monolaurate (Span 20), polyoxyethylene(5)nonylphenylether with ethoxy numbers of 5 (Igepal
CO-520) and polyoxyethylene sorbitan monooleate (Tween 80) of hydrophilic-lipophilic balance (HLB) values of 4.3, 8.6, 10
and 15 respectively. Among the surfactants, the intermediate HLB values of 8.6 (Span 20) and 10 (Igepal CO-520) were effective
in synthesizing highly dispersible NaA nanoparticles of size 50–65 nm. The membrane prepared hydrothermally in multi-steps
at 65 ± 1°C, using the Span 20-derived seed crystals deposited on porous support, showed the formation of high quality interlocked
NaA coating. Single gas nitrogen (N2) permeation of the membrane exhibited a permeance value of 1.01 × 10−8 mol m−2 s−1 Pa−1 at ambient temperature (30°C). 相似文献
998.
A. Topkar A. SinghS. Santra P.K. MukhopadhyayA. Chatterjee R.K. ChoudhuryC.K. Pithawa 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,654(1):330-335
An integrated ΔE-E silicon detector telescope using silicon planar technology has been developed. The technology developed is based on standard integrated circuit technology and involves double sided wafer processing. The ΔE and E detectors have been realized in a PIN configuration with a common buried N+ layer. Detectors with ΔE thicknesses of 10, 15 and 25 μm, and E detector with thickness of 300 μm have been fabricated and tested with alpha particles using 238Pu-239Pu dual alpha source. The performance of the detector with ΔE detector of thickness 10 μm and E detector of thickness 300 μm has been studied for identification of charged particles using 12 MeV 7Li+ ion beam on carbon target. The results of these tests demonstrate that the integrated detector telescope clearly separates the charged particles, such as alpha particles, protons and 7Li. Due to good energy resolution of the E detector, discrete alpha groups corresponding to well known states of 15N populated during the reaction could be clearly identified. 相似文献
999.
Image-based quality monitoring system of limestone ore grades 总被引:1,自引:0,他引:1
Snehamoy Chatterjee Author Vitae Ashis Bhattacherjee Author Vitae Biswajit Samanta Author Vitae Samir Kumar Pal Author Vitae 《Computers in Industry》2010,61(5):391-36
In this study, an image analysis-based ore quality monitoring system was developed. The study was conducted at a limestone mine located in India. The samples were collected based on a stratified random sampling method, and images of these samples were taken in a simulated environment in a laboratory. The image preprocessing and segmentation were performed using different segmentation methods to extract morphological, colour and textural features. A total of 189 features was extracted during this study. Principal components analysis was conducted to reduce the feature vector for modeling purposes. Five principal components, which were extracted from the feature vectors, captured 95% of the total feature variance. A neural network model was used as a mapping function for ore grade prediction. The five principal components were used as input, and four grade attributes of limestone (CaO, Al2O3, Fe2O3 and SiO2) were used as output. The developed model was then used for day to day quality monitoring at 3 different face locations of the mine. Results revealed that this technique can be successfully used for ore grade monitoring at the mine level in a controlled environment. 相似文献
1000.
Anindita Bose Kuntal Chatterjee Dipankar Chakravorty 《Bulletin of Materials Science》2009,32(3):227-230
Junctions of silver-copper oxide and silver-zinc oxide, respectively were prepared within the pores of diameters, 20 nm, in
anodic aluminium oxide membranes. Voltage-current characteristics were measured over the temperature range 373–573 K which
showed rectification behaviour. Using the standard equation the difference between the work functions of the metal and the
semiconductor was calculated. This showed a variation with the temperature of measurement. This is explained as arising due
to the effect of pressure generated as a result of thermal expansion of the metallic phases concerned between the electrodes.
This is consistent with the theoretical prediction of Fermi level shifting of the semiconductor within the bandgap as a function
of pressure.
Dedicated to Prof. C N R Rao 相似文献