排序方式: 共有61条查询结果,搜索用时 15 毫秒
31.
Dey Subhrajit Roychoudhury Rajarshi Malakar Samir Sarkar Ram 《Multimedia Tools and Applications》2022,81(7):9331-9349
Multimedia Tools and Applications - Breast cancer, the most common invasive cancer, causes deaths of thousands of women in the world every year. Early detection of the same is a remedy to lessen... 相似文献
32.
Paital SR Bunce N Nandwana P Honrao C Nag S He W Banerjee R Dahotre NB 《Journal of materials science. Materials in medicine》2011,22(6):1393-1406
A textured calcium phosphate based bio-ceramic coating was synthesized by continuous wave Nd:YAG laser induced direct melting
of hydroxyapatite precursor on Ti–6Al–4V substrate. Two different micro-textured patterns (100 μm and 200 μm line spacing)
of Ca–P based phases were fabricated by this technique to understand the alignment and focal adhesion of the bone forming
cells on these surfaces. X-ray diffraction studies of the coated samples indicated the presence of CaTiO3, α-Ca3(PO4)2, Ca(OH)2, TiO2 (anatase) and TiO2 (rutile) phases as a result of the intermixing between the precursor and substrate material during laser processing. A two
dimensional elemental mapping of the cross-section of the coated samples exhibited the presence of higher phosphorous concentration
within the coating and a thin layer of calcium concentration only at the top of the coating. Improved in vitro bioactivity
and in vitro biocompatibility was observed for the laser processed samples as compared to the control. 相似文献
33.
Todd J. Spencer Yu-Chun Chen Rajarshi Saha Paul A. Kohl 《Journal of Electronic Materials》2011,40(6):1350-1363
Incorporation of copper ions into poly(propylene carbonate) (PPC) films cast from γ-butyrolactone (GBL), trichloroethylene
(TCE) or methylene chloride (MeCl) solutions containing a photo-acid generator is shown to stabilize the PPC from thermal
decomposition. Copper ions were introduced into the PPC mixtures by bringing the polymer mixture into contact with copper
metal. The metal was oxidized and dissolved into the PPC mixture. The dissolved copper interferes with the decomposition mechanism
of PPC, raising its decomposition temperature. Thermogravimetric analysis shows that copper ions make PPC more stable by up
to 50°C. Spectroscopic analysis indicates that copper ions may stabilize terminal carboxylic acid groups, inhibiting PPC decomposition.
The change in thermal stability based on PPC exposure to patterned copper substrates was used to provide a self-aligned patterning
method for PPC on copper traces without the need for an additional photopatterning registration step. Thermal decomposition
of PPC is then used to create air isolation regions around the copper traces. The spatial resolution of the self-patterning
PPC process is limited by the lateral diffusion of the copper ions within the PPC. The concentration profiles of copper within
the PPC, patterning resolution, and temperature effects on the PPC decomposition have been studied. 相似文献
34.
Rajarshi Mukherjee Jawahar Jain Koichiro Takayama Jacob A. Abraham Donald S. Fussell Masahiro Fujita 《Formal Methods in System Design》2002,21(1):95-101
We propose a novel methodology that combines local BDDs with a hash table for very efficient verification of combinational circuits. The main purpose of this technique is to remove the considerable overhead associated with case-by-case verification of internal node pairs in typical internal correspondence based verification methods. Two heuristics based on the number of structural levels of circuitry looked at and the total number of nodes in the BDD manager are used to control the BDD sizes and introduce new cutsets based on already found equivalent nodes. We verify the ISCAS85 benchmark circuits and demonstrate significant speedup over existing methods. We also verify several hard industrial circuits and show our superiority in extracting internal equivalences. 相似文献
35.
Christopher H. Brooks Robert S. Gazzale Rajarshi Das Jeffrey O. Kephart Jeffrey K. MacKie–Mason & Edmund H. Durfee 《Computational Intelligence》2002,18(4):566-582
As online markets for the exchange of goods and services become more common, the study of markets composed, at least in part, of autonomous agents has taken on increasing importance. In contrast to traditional complete–information economic scenarios, agents that are operating in an electronic marketplace often do so under considerable uncertainty. In order to reduce their uncertainty, these agents must learn about the world around them. When an agent producer is engaged in a learning task in which data collection is costly, such as learning the preferences of a consumer population, it is faced with a classic decision problem: when to explore and when to exploit. If the agent has a limited number of chances to experiment, it must explicitly consider the cost of learning (in terms of foregone profit) against the value of the information acquired. Information goods add an additional dimension to this problem; due to their flexibility, they can be bundled and priced according to a number of different price schedules. An optimizing producer should consider the profit each price schedule can extract, as well as the difficulty of learning of this schedule. In this paper, we demonstrate the tradeoff between complexity and profitability for a number of common price schedules. We begin with a one–shot decision as to which schedule to learn. Schedules with moderate complexity are preferred in the short and medium term, as they are learned quickly, yet extract a significant fraction of the available profit. We then turn to the repeated version of this one–shot decision and show that moderate complexity schedules, in particular two–part tariff, perform well when the producer must adapt to nonstationarity in the consumer population. When a producer can dynamically change schedules as it learns, it can use an explicit decision–theoretic formulation to greedily select the schedule which appears to yield the greatest profit in the next period. By explicitly considering both the learnability and the profit extracted by different price schedules, a producer can extract more profit as it learns than if it naively chose models that are accurate once learned. 相似文献
36.
37.
This paper proposes and evaluates a four-wave mixing (FWM) aware evolutionary programming algorithm for dynamically setting
up lightpaths in an optical wavelength division multiplexed network (WDM network). The proposed algorithm also considers the
effect of amplified spontaneous emission noise (ASE noise) on a lightpath during propagation of the optical signal from any
source to the intended destination. As crosstalk due to FWM and ASE noise are two transmission impairments that degrade the
quality of optical signal even at low to medium data rates, it is mandatory for an algorithm for dynamic routing and wavelength
assignment in a WDM network to consider the effect of these two impairments on the lightpath to be established. The distinguishing
feature of the proposed algorithm is that it is based on an initial population of a single individual and uses a fitness function
that is expressed in terms of the number of hops, path cost, variance contributions due to FWM crosstalk, amplifier noise,
and different beat noises at the receiver. The performance of a newly introduced FWM aware priority-based wavelength assignment
technique is compared with few of the existing wavelength assignment techniques in the present work. 相似文献
38.
High dielectric constant aluminum oxide (Al(2)O(3)) is frequently used as the gate oxide in high electron mobility transistors and the impact of its deposition by radio frequency (RF) magnetron sputtering on the structural and electrical properties of multilayer epitaxial graphene (MLG) grown by graphitization of silicon carbide (SiC) is reported. Micro-Raman spectroscopy and temperature dependent Hall mobility measurements reveal that the processing induced changes to the structural and electrical properties of the MLG can be minimal when the oxide deposition conditions are optimal. High-resolution transmission electron microscopy (HRTEM) analysis confirms that the Al(2)O(3)/MLG interface is relatively sharp and that our thickness approximation of the MLG using angle resolved x-ray photoelectron spectroscopy (ARXPS) is accurate. An interface trap density of 5.1 × 10(10) eV(-1) cm(-2) was determined using capacitance-voltage techniques. The totality of our results indicates that ARXPS can be used as a nondestructive tool to measure the thickness of MLG, and that RF sputtered Al(2)O(3) can be used as a high dielectric (high-k) constant gate oxide in multilayer graphene based transistor applications. 相似文献
39.
Stéphane Gorsse Christopher Hutchinson Mohamed Gouné Rajarshi Banerjee 《Science and Technology of Advanced Materials》2013,14(1):584-610
AbstractWe present a brief review of the microstructures and mechanical properties of selected metallic alloys processed by additive manufacturing (AM). Three different alloys, covering a large range of technology readiness levels, are selected to illustrate particular microstructural features developed by AM and clarify the engineering paradigm relating process–microstructure–property. With Ti-6Al-4V the emphasis is placed on the formation of metallurgical defects and microstructures induced by AM and their role on mechanical properties. The effects of the large in-built dislocation density, surface roughness and build atmosphere on mechanical and damage properties are discussed using steels. The impact of rapid solidification inherent to AM on phase selection is highlighted for high-entropy alloys. Using property maps, published mechanical properties of additive manufactured alloys are graphically summarized and compared to conventionally processed counterparts. 相似文献
40.
Shivprasad P. Patil Rajarshi Sanyal Ramjee Prasad 《Wireless Personal Communications》2018,100(2):283-309
Traffic surveillance has been one of the essential attributes in smart city concept. Nowadays, in such applications rotating camera is preferred over static camera. Motivation behind this substitution is to reduce the cost of data transmission and Total of cost of ownership. To design an optimal and performant wireless ‘smart city area network’ for video surveillance systems, this paper focuses on some key areas, namely, transmission efficiency, lossless video data coding, data congestion, edge computing at transmission nodes. The end objective is to achieve high quality received video stream in spite of compressed data transmission. Some research initiatives in this domain are pertinent. For example, Structural Similarity Index (SSIM) based rate distortion optimization is an effective tool in enhancing the perceptual video quality in wireless environments. However, prevailing system does not consider the network congestion conditions, affecting quality of received video. Also, effect of distortion introduced by ‘channel noise’ is unattended. This motivated us to propose a new dual metric traffic control mechanism, wherein both metrics i.e. distortion and data congestion are considered. It is based on an ‘improvised SSIM’ method which incorporates the ‘Rate of allocation’ algorithm as a function. Experimental results unveil that the proposed traffic control using similarity index under noise diversity can achieve better video quality and more data throughput. 相似文献