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排序方式: 共有13条查询结果,搜索用时 250 毫秒
1.
Data compression and encryption using cellular automata transforms   总被引:2,自引:0,他引:2  
A family of basis functions, generated from the evolving states of Cellular Automata (CA), is used to compress and encrypt data. The operations required in encoding and decoding the data are described under the umbrella Cellular Automata Transforms (CAT). There is a huge number of these transform bases. CAT can be used in the way other mathematical transforms (e.g., Fourier, Discrete Cosine, Laplace, Wavelet, etc.) are utilized. In data-compression applications, the rules and pertinent keys used to generate the CA are selected to favor those that yield basis functions with the best information-packing characteristics. On the other hand, for encryption the selection is biased towards those with the tendency to yield an avalanche effect. In the latter case the transform process must be error-free.  相似文献   
2.
This paper explores in detail, the microstructures and thermoelectric properties of Te-rich and Te-poor (Bi,Sb)2Te3 alloys. We show that tuning the composition of ternary Bi–Sb–Te type alloys allows us to synthesize a range of microstructures containing a primary solid solution of (Bi,Sb)2Te3 with varying amounts of Te solid solution or a (Bi,Sb)Te compound. Te exists as a constituent of the multilayer domain while (Bi,Sb)Te appears in the thin intercellular regions of the (Bi,Sb)2Te3 dendritic cells. The presence of Te imparts an n-type behavior to the composite while the (Bi,Sb)2Te3 with a small amount of (Bi,Sb)Te exhibits p-type properties. A maximum ZT value of ≈0.4 at 425 K was achieved, opening up the possibility of using these alloys for thermoelectric device applications.  相似文献   
3.
A control strategy is developed to control molecular weight of recycled poly(ethylene terephthalate), PET, to overcome its degradation through an extrusion process. To obtain dynamic model of a twin screw extruder, steady‐state, and unsteady‐state experiments were performed. Discrete convolution models between inputs and outputs were obtained. Process inputs were considered as screw speed (SS), feed rate, and barrel temperatures and the output was viscosity average molecular weight (Mv) of the extrudate. SS and molecular weight of the product were chosen as the manipulated, controlled variable pair by considering singular value decomposition (SVD) technique. Model based PID controller and model predictive controller were used in the designed control scheme. By the simulation studies, both controllers were found to be successful for set‐point tracking, disturbance rejection cases; and were proven to be robust under modeling errors. POLYM. ENG. SCI., 54:459–465, 2014. © 2013 Society of Plastics Engineers  相似文献   
4.
The functional and tableting properties of native (NaFM) and chemically modified (by acetylation, AcFM; and oxidation, OxFM) finger millet starches were investigated. The tablet formation properties of the starches were assessed by Heckel and Kawakita analysis. The swelling power and solubility of the starch increased with increase in temperature with AcFM having the highest swelling power, while OxFM had the highest solubility. X‐ray diffractometry showed that the starches had the characteristic ‘A’ pattern with strong peaks at 3.78, 4.37, 4.87, and 5.17 Å. Chemical modification causes rupture of some starch granules as revealed by the Scanning Electron Micrograph. Chemical modification also leads to improved gelatinisation profile, with reduction in ΔHgel from 9.64 J/g (NaFM) to 3.88 J/g (AcFM) and 8.76 J/g (OxFM). The bulk density and Hausner's ratio increased after chemical modification of the starch. Chemical modification reduced the mean yield pressure, Py (Heckel analysis) but increased the deformability Pk (Kawakita analysis) of the starch compacts. Chemical modification also increased the crushing and tensile strength of the starch compacts, but lowered its disintegration time and friability.  相似文献   
5.
Eighteen chronic schizophrenia patients and 14 controls were given tests that have been linked primarily to ventral (orbitofrontal) or to dorsolateral prefrontal dysfunctions in neurological patients and in nonhuman animal Ss having discrete frontal lesions. Schizophrenia patients were significantly impaired on object alternation and delayed alternation tasks but not on classical delayed response (DR). Schizophrenia patients performed well on the classical version of the DR task and their DR performance correlated significantly with measures of sustained attention. Future research is needed to interpret the contributions of attention, interference, and memory load to neuropsychological performance in schizophrenia. Additional studies are required to determine whether the frontal deficits reflect diffuse brain damage, circumscribed prefrontal damage, or damage in other brain regions having prefrontal connections. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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7.
ICT Innovation is one of the major forces for socioeconomic development. It is the key element to spur growth of the economy of a nation. Several studies have shown that culture is a crucial determinant of innovations. This study examines the effect of socio-cultural factors on ICT innovation with specific focus on the mobile banking services. Research was conducted on 220 respondents from sampled population in South Africa. The questionnaire used in this study was developed based on previous studies that have proven validity. The findings indicate that culture is an appropriate concept to describe how innovation in information and communication technology can be influenced by human behavior.  相似文献   
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9.
Dual-reciprocity BEM based on global interpolation functions   总被引:2,自引:0,他引:2  
Several global shape functions are introduced to interpolate the body-force term in the dual-reciprocity boundary-element method. These global-interpolation functions, which include polynomial, trigonometric, and hyperbolic series, can be used in place of the locally based radial shape function. For the several examples presented, the global functions have demonstrated superior convergence properties.  相似文献   
10.
When maize and soybeans were stored under ambient conditions (26ǃ °C/RH 75LJ%) using the ground material of the spice Aframomum danielli (family Zingiberaceae), mouldiness and insect infestation were controlled for 15 months. After eight weeks of storage, chemical compositions of maize and soybeans (moisture content, mc 10.0%) treated with 4.0%, 6.0% and 8.0% ground powder of A. danielli did not differ significantly (P=0.05) from those of untreated (control) samples. However, chemical compositions of samples maintained at 15.0% and 20.0% mc respectively were different from those of control samples (P>0.05). At 10.0% mc, maize and soybean samples treated with different concentrations of A. danielli powder were preferred to treated samples maintained at 15.0% and 20.0% respectively. The preservative capability of the powder of A. danielli was associated with phytochemical components tentatively identified as alkaloids. Viability of maize and soybeans was not affected by treatment with A. danielli powder. The powder of A. danielli has some protective effects on liver cells because it exerted no hepatotoxic effect on test albino rats as serum enzyme levels of glutamate oxaloacetate transmaminase (SGOT), glutamate pyruvate transaminase (SGPT) and alkaline phosphatase (ALP) were lowered by 67.0%, 86.3% and 49.7% respectively when compared with control albino rats not fed with A. danielli powder in their rations (meals).  相似文献   
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