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排序方式: 共有483条查询结果,搜索用时 15 毫秒
1.
Wireless Personal Communications - Biometric traits are frequently used by security agencies for automatic recognition of a person. There are numerous biometric traits used for person... 相似文献
2.
A general method for determining whether a certain design is initializable, and for generating its initialization sequence, is presented in this paper. This method is based on structural decomposition of the circuit, and can handle both logical (using X-value simulation) and functional initializability. The routines developed are then used for ATPG of sequential circuits. A pre-test sequence that initializes the good and as many of the faulty machines as possible is generated and used in conjunction with CRIS [5], a simulation based sequential ATPG program, to generate a test set for the circuit. 相似文献
3.
The applications of nanotechnology in oilfields have attracted the attention of researchers to nanofluid injection as a novel approach for enhanced oil recovery. To better understand the prevailing mechanisms in such new displacement scenarios, micromodel experiments provide powerful tools to visually observe the way that nanoparticles may mobilize the trapped oil. In this work, the effect of silicon oxide nanoparticles on the alteration of wettability of glass micromodels was investigated in both experimental and numerical simulation approaches. The displacement experiments were performed on the original water-wet and imposed oil-wet (after aging in stearic acid/n-heptane solution) glass micromodels. The results of injection of nanofluids into the oil-saturated micromodels were then compared with those of the water injection scenarios. The flooding scenarios in the micromodels were also simulated numerically with the computational fluid dynamics (CFD) method. A good agreement between the experimental and simulation results was observed. An increase of 9% and 13% in the oil recovery was obtained by nanofluid flooding in experimental tests and CFD calculations, respectively. 相似文献
4.
Muhammad Yaseen Kashif Saleem Mehmet A. Orgun Abdelouahid Derhab Haider Abbas Jalal Al-Muhtadi Waseem Iqbal Imran Rashid 《Telematics and Informatics》2018,35(4):702-726
Recent advances in hardware technology have led to the development of low cost, power efficient and more feature rich devices that are amongst the most critical parts of communication networks. These devices or sensors can now sense data with more accuracy, process it by themselves and send it to the neighboring node or the sink node. However, robust and reliable security mechanisms are not yet properly implemented on these sensors due to their limited energy and computation power. Sensors also play a very important role in eHealthcare systems where ubiquitous patient monitoring is performed. As data is generated from the sensor nodes, reliable, secure and attack-resistant data acquisition and transmission is important for an efficient eHealthcare systems. This survey focuses on security issues of sensors data acquisition and transmission protocols, describing their main security features and comparing them in the context of a secure eHealthcare system. A taxonomy of open issues and future challenges is also discussed with respect to specific security metrics described in the paper. 相似文献
5.
Adsorption of methane on corn cobs based activated carbon 总被引:1,自引:0,他引:1
Activated carbon was prepared with corn cobs and potassium hydroxide under optimized variables. Due to their botanical origin, corn cobs can be an excellent starting material to produce nanoporous carbon for natural gas storage. Samples with different BET surface areas were chosen to perform methane adsorption experiments. Methane adsorptions on corn cob based activated carbon were studied at four different pressures (500, 1000, 1500 and 2000 psi) and two different temperatures (298 K and 323 K) in a volumetric adsorption apparatus. The volume based methane adsorption results specified an ‘increase in the methane adsorption capacities of activated carbon with increasing surface area and showed that adsorption capacity of methane depends on pressure and temperature. The highest methane storage capacity was found to be 160 (v/v) at 298 K and 1500 psi. The applications include use in the transportation of natural gas, natural gas based vehicles, and adsorption of gas from landfills. 相似文献
6.
Javad Sargolzaei Amin Hedayati Moghaddam Jalal Shayegan 《Korean Journal of Chemical Engineering》2011,28(9):1889-1896
The present work deals with application of 25-2 fractional factorial design (FFD) to evaluate the operating parameters on starch separation from synthetic starchy wastewater
using a hydrophilic polyethersulfone membrane with 0.65 μm pore size in a plate and frame handmade membrane module. The analysis
of variance (ANOVA) combined with F-test was also used to recognize non-significant terms. The performance of the filtration process was evaluated by calculating
the COD removal percentage (rejection factor) and permeate flux. In this experiment, five input parameters were surveyed,
including trans membrane pressure (TMP), flow and temperature of feed, pH and concentration of wastewater. In this experiment,
real wastewater was not used but synthetic starchy wastewater was prepared using starch. Two models were obtained from experimental
data, capable of predicting COD removal percentage and permeate flux in different conditions. The predicted values obtained
from the regression models were close to the actual ones. For the reduction of fouling, cleaning in place (CIP) method was
used. 相似文献
7.
Kourosh Kabiri Speideh Lashani Mohammad Jalal Zohuriaan-Mehr Malihe Kheirabadi 《Journal of Polymer Research》2011,18(3):449-458
Alcohol-specific superabsorbing gels (super-alcogels) based on non-neutralized acrylic acid (AA, 60–94 mol%) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) were prepared
via solution polymerization in water. Polyethylene glycol dimethacrylate and potassium persulfate were used as crosslinker
and initiator, respectively. Characterization of samples was performed using FTIR, 1H-NMR and thermomechanical analyses. Glass transition temperature and modulus of dried samples were found to be directly changed
with their AA content. The gels exhibited enormous ability for absorbing and retaining a variety of mono- and poly-hydric
alcohols. For example, in lieu of one gram of a typical sample composing 25 mol% AMPS, its absorption capacity was measured
to be 53.0 g methanol, 42.1 g ethanol, 12.1 g n-propanol, 3.4 g iso-propanol, 41.2 g ethylene glycol, 20.7 g propylene glycol, 37.8 g 1,3-propanediol and 32.9 g glycerol. The absorbencies were
superior to those of a known commercial poly(AA) sample, Carbopol. The alcohol absorbency was improved with increase of AMPS
incorporated. It was recognized to be dependant on the alcohol characteristics such as H-bonding ability, OH/C ratio, electronic
features (e.g. dielectric constant), steric hindrance of the neighboring groups of the solvent OH group, as well as the solvent
viscosity. Normal phase transitions were observed in the gel swelling behavior in the alcohol-water binary mixtures. Rheological
measurements of the water-swollen gel showed that more AMPS content resulted in gels with inferior storage modulus. All the
empirical observations were discussed based on the related physicochemical principles. 相似文献
8.
A three‐dimensional simulation of the Underground coal gasification (UCG) process is studied in terms of the heat and mass transport phenomena and chemical kinetics in a coal seam during coal combustion by applying the controlled retracting injection point technique. The STARS module of the Computer Modelling Group software is used in this study. The gas species flow rate, cavity shapes, and temperature profile in the coal seam during gasification are investigated. The main motivation behind this study is to provide a simulation methodology by using a comprehensive porous media flow approach to understand the critical aspects of the UCG process. 相似文献
9.
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