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排序方式: 共有462条查询结果,搜索用时 31 毫秒
411.
A.A. Ismaeel R. Mathew R. BhatnagarAuthor vitae 《Computers & Electrical Engineering》1998,24(6):441-461
In this paper, we present a scheduling and a variable binding technique for improved testability in high level synthesis. The scheduling technique called cost based scheduling system (CBSS), is time constrained which minimizes the number of resources (operations) and the number of registers based on a cost function. The CBSS improves the life time of primary input and primary output variables, reduces the life times of intermediate variables and hence improves the controllability and observability. The testability of the register transfer level (RTL) structure generated by this schedule is therefore improved. CBSS considers all the variables and operations jointly for scheduling. CBSS supports various scheduling modes such as multicycled and chained operations, and pipelining. The complexity of our scheduling algorithm is O(c·n2) where c is the number of control steps and n is the number of operations to be scheduled. To generate a highly testable RTL structure, the CBSS is followed by a variable binding technique to bind the variables into registers. An integer linear programming (ILP) approach is proposed with an objective function that minimizes the number of registers and a set of constraints that improves the testability of the RTL structure. Various case studies are presented and the results on different benchmark examples show the potential of our approach. 相似文献
412.
The present study has been carried out to investigate the effect of fluoride toxicity on the morphology as well as inorganic chemical constituents of rabbit teeth. Rabbits were administered sodium fluoride at a dose of 10 mg NaF/kg body weight every 24 h for 18 and 23 months. The incisor and molar teeth (whole tooth) were investigated for fluoride, calcium and phosphorus content in 18- and 23-month treated animals. The enamel surfaces of incisor teeth of 23-month treated animals were examined under scanning electron microscope. A significant increase in fluoride levels and significant decrease in calcium content was found following fluoride administration for 18 and 23 months as compared to control. Ca/P ratio was significantly increased only in 23-month treated animals. The scanning electron micrographs revealed hypoplastic, rough, uneven, pitted and cracked enamel surfaces covered with granular deposits as a result of excessive intake of fluoride. It can be concluded that long term fluoride administration leads to severe structural alterations on the enamel surface, possibly through defective mineralization. 相似文献
413.
414.
An efficient ad recommendation system for TV programs 总被引:1,自引:0,他引:1
415.
Tri-O-α-naphthylmethyl cellulose was prepared by homogeneous phase reaction using SO2–diethylamine (DEA)–dimethyl sulfoxide (DMSO) as the solvent system. Observations made by dynamic mechanical spectrometry and by cross-polarized optical microscopy revealed liquid crystalline behavior for the concentrated solutions of tri-O-α-naphthylmethyl cellulose in dimethylacetamide (DMAc). Experimental and calculated (predicted) critical volume fraction of the derivative, Vcp, did not show agreement. It is determined that Vcp is affected by bulky substituents on the cellulose backbone to some extent. © 1993 John Wiley & Sons, Inc. 相似文献
416.
417.
Somnath C. Roy G.L. Sharma M.C. Bhatnagar R. Manchanda V.R. Balakrishnan S.B. Samanta 《Materials Chemistry and Physics》2006,100(2-3):404-410
The effect of pre-sintering temperature on the activation energies of dc and ac conduction in sol–gel spin-coated Ba0.5Sr0.5TiO3 (BST) thin films is reported in this paper. Layer by layer coating of BST sol on Pt/TiN/SiO2/Si substrates was done with varying pre-sintering temperatures (drying temperature for individual layers). Dominant mechanism of dc conduction was identified as Schottky process whereas ac conduction was governed by trap controlled hopping process. The activation energy for dc conduction decreased from 0.45 to 0.38 eV with increase in the pre-sintering temperature from 400 to 600 °C; whereas, that for ac conduction increased from 0.17 to 0.21 eV. The results have been correlated with grain growth phenomena and reduction of oxygen vacancies in the films with increase in the pre-sintering temperature. 相似文献
418.
419.
Although information plays a major role in effective functioning of supply chain networks (SCNs), studies that deal specifically
with the dynamics of supply chains are few. This problem is relatively new since fast communications and the means to employ
it for effective management of supply chains did not exist till recently. In order to provide a vehicle for dynamic modelling
and analysis of supply chain operations in vague and uncertain environments, we propose a fuzzy enhanced high level petri
net (FEHLPN) model. The proposed model captures the capability of petri nets for graphical and analytical representation of
dynamic SCNs with the management of uncertain information provided by fuzzy logic. The dynamics associated with two production
planning and control policies are modelled, viz. make-to-stock and assemble-to-order in vague and ambiguous situations in
electronic commerce environment. A fuzzy set and fuzzy truth-values are attached to an uncertain fuzzy token to model imprecision
and uncertainty. The proposed FEHLPN incorporates essential aspects of rule-based systems, such as conservation of facts,
refraction, and closed-world assumption. 相似文献
420.
Miaosi Li Brendan Dyett Haitao Yu Vipul Bansal Xuehua Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(1)
A universal femtoliter surface droplet‐based platform for direct quantification of trace of hydrophobic compounds in aqueous solutions is presented. Formation and functionalization of femtoliter droplets, concentrating the analyte in the solution, are integrated into a simple fluidic chamber, taking advantage of the long‐term stability, large surface‐to‐volume ratio, and tunable chemical composition of these droplets. In situ quantification of the extracted analytes is achieved by surface‐enhanced Raman scattering (SERS) spectroscopy by nanoparticles on the functionalized droplets. Optimized extraction efficiency and SERS enhancement by tuning droplet composition enable quantitative determination of hydrophobic model compounds of rhodamine 6G, methylene blue, and malachite green with the detection limit of 10?9 to 10?11 m and a large linear range of SERS signal from 10?9 to 10?6 m of the analytes. The approach addresses the current challenges of reproducibility and the lifetime of the substrate in SERS measurements. This novel surface droplet platform combines liquid–liquid extraction and highly sensitive and reproducible SERS detection, providing a promising technique in current chemical analysis related to environment monitoring, biomedical diagnosis, and national security monitoring. 相似文献