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2.
In this paper we present a scale model for fitting an ideal shape to an object. The measurements of the object are taken corresponding to a fixed coordinate system at a set of well-defined locations on the surface of the object. We propose an algorithm to estimate the model parameters and hypothesis tests to make statistical inferences about several possible special cases of the general model. The model is tested with an example that analyzes data on the feet of people in Hong Kong.  相似文献   
3.
The methodology of response reactions (RERs) introduced earlier from thermodynamic and kinetic considerations is used in this work to develop a new algorithm for the classification and enumeration of unique/direct reaction routes (RRs) and overall reactions (ORs). According to the RERs approach, a unique set of both RRs and ORs may be generated starting from any conceivable set of linearly independent RRs and ORs. In particular, the direct ORs may be most conveniently enumerated starting from the formula matrix of the terminal species (reactants and products), i.e., without any relation to the elementary reactions comprising the detailed mechanism. Depending on the type of ORs produced by the RRs one can distinguish between two distinct types of direct RRs. Namely, one option is to define a direct RR by specifying the intermediate species that need to be eliminated. This type of RR is referred to as Milner RRs. The other option is to require the direct RRs to produce RERs, thus resulting in RRs referred to as Happel-Sellers RRs.  相似文献   
4.
More than just a regulatory body, the data administration group is responsible for planning and promoting the use of information resources. By managing the corporate data base effectively, data administration provides benefits to everyone who depends on the use of accurate information.  相似文献   
5.
ABSTRACT

Nano-composite polymer gel electrolytes (NPGEs) based on polymer poly(vinylidene fluoride-co-hexafluoropropylene) PVdF-HFP, ionic liquid, 1-butyl-3- methylimidazolium bis(trifluoromethanesulfonyl)imide BMIMTFSI, Li-salt along with the addition of SiO2 nanoparticles have been synthesized and characterized by various techniques. Prepared NPGEs show high room temperature ionic conductivity (~10?3 S/cm) and have a wide electrochemical window (ECW) (~3.3–3.5 V). The galvanostatic charge/discharge profile was studied by sandwiching best performing NPGEs between a LiFePO4 cathode and lithium metal anode. The specific discharge capacity of the cell (Li/NPGE/LiFePO4) room temperature at 0.1C rate is found to be 138 mAh/g.  相似文献   
6.
In this study, an attempt has been made to find the correlation between diffusion tensor imaging (DTI) indices of white matter (WM) regions and mini mental state examination (MMSE) score of Alzheimer patients. Diffusion weighted images are obtained from the ADNI database. These are preprocessed for eddy current correction and removal of non-brain tissue. Fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (DA) indices are computed over significant regions (Fornix left, Splenium of corpus callosum left, Splenium of corpus callosum right, bilateral genu of the corpus callosum) affected by Alzheimer disease (AD) pathology. The correlation is computed between diffusion indices of the significant regions and MMSE score using linear fit technique so as to find the relation between clinical parameters and the image features. Binary classification has been employed using support vector machine, decision stumps and simple logistic classifiers on the extracted DTI indices along with MMSE score to classify Alzheimer patients from healthy controls. It is observed that distinct values of DTI indices exist for the range of MMSE score. However, there is no strong correlation (Pearson's correlation coefficient ‘r’ varies from 0.0383 to −0.1924) between the MMSE score and the diffusion indices over the significant regions. Further, the performance evaluation of classifiers shows 94% accuracy using SVM in differentiating AD and control. In isolation clinical and image features can be used for prescreening and diagnosis of AD but no sub anatomic region correlation exist between these features set. The discussion on the correlation of diffusion indices of WM with MMSE score is presented in this study.  相似文献   
7.
In the present study, the effect of lifting task parameters on the heart rate and oxygen uptake of workers during manual lifting tasks in different ambient conditions was evaluated. The experiments conducted in two different temperature conditions showed a significantly higher oxygen uptake and heart rate in colder conditions as compared to warmer conditions. Three other factors, namely, load, lifting frequency, and vertical distance were found to significant affect the responses. Various combinations of significant factors were used to calculate oxygen uptake and heart rate. These were then compared with the safe limits as per the maximum aerobic capacity of workers. Based on these comparisons, the safe combinations were identified that can be used to design lifting tasks in varied ambient conditions. The study further concluded that lifting tasks performed in winter should have different relaxation or fatigue allowances built into the cycle time of the task to compensate for higher exertion. © 2011 Wiley Periodicals, Inc.  相似文献   
8.
The experimental results on the effect of adding trimethylethoxysilane (TMES) as a co-precursor on the hydrophobicity and physical properties of tetraethoxysilane (TEOS) based silica aerogels, are reported. The molar ratio of TEOS, ethanol (EtOH), water (0.001 M oxalic acid catalyst) was kept constant at 1:5:7 respectively, while the molar ratio of TMES/TEOS (A) was varied from 0 to 0.6. It has been observed that as the A value increases, the gelation time increases. The hydrophobicity was tested by measuring the contact angle, and the surface chemical modification was confirmed by the FTIR spectroscopy studies. The thermal stability of the hydrophobic aerogels was studied in the temperature range from 25 to 800°C. The hydrophobic nature of the aerogel could be maintained up to a temperature of 287°C and above this temperature the aerogels become hydrophilic. The bulk density and the optical transmittance of the aerogels have been found to decrease with increase in A value. The aerogels have been characterized by Fourier transform infrared spectroscopy (FTIR), Optical transmittance, Scanning electron microscopy (SEM), Differential thermal analysis (DTA) and Thermogravimetric analysis (TGA), and Contact angle measurements.  相似文献   
9.
To improve the economic feasibility of hydrolyzing fats and oils with moist oat caryopses, various factors affecting the efficiency of the process were studied. Caryopses produced with an impact-type dehuller exhibited greater lipase activity than those produced by a wringer-type dehuller. Abrasion of oat caryopses against each other in a fluidized bed released particles rich in lipase. Such lipase concentrates could be added to moist caryopsis reactors to speed fat hydrolysis. Beef tallow, lard, soybean oil and crambe oil were hydrolyzed more efficiently than corn oil, castor oil and milk fat. The poor hydrolysis of castor oil was attributed to the formation of esters with the hydroxy group of ricinoleic acid, and the hydrolysis of castor oil was increased by dilution of the substrate with hexane. Diglycerides inhibited the hydrolysis and accounted for the slower hydrolysis of corn oil. Hydrolysis of milk fat by moist oat caryopses resulted in preferential hydrolysis of C6 to C10 acids. Erucic acid was released from crambe oil at significantly slower rates than the other acyl groups. High conversions of fats and oils to free fatty acids could be attained by (i) exposing the fats and oils to two to three lots of moist caryopses, (ii) the use of special oat varieties with elevated lipase content, (iii) the addition of oat lipase concentrates to moist caryopsis reactors, and (iv) dilution of the substrate with hexane. Estimates of the cost of producing free fatty acids with these processes indicated that the first three should be profitable. Growth ofClostridium sporogenes spores could not be demonstrated in caryopsis reactors. During the incubation of moist oat caryopses immersed in oil, the free fatty acid content of the internal caryopsis lipid increased only slightly, but there were changes in its fatty acid composition.  相似文献   
10.
Model accuracy plays a key role in the performance of advanced, model predictive control algorithms. Model fidelity is usually affected by routine operating condition changes, which necessitate reidentification. From several theoretical and practical considerations, it is recommended that such re-identification be performed under closed-loop conditions. The direct approach for closed-loop identification, owing to its simplicity, is better suited for MPC. In order to yield unbiased and consistent parameter estimates, however, this approach requires the noise model to be sufficiently parameterized. Towards this objective, high order ARX models are the most suitable candidates from the viewpoint of ease of parameter estimation. For multivariable systems, however, the identification of high order ARX models would require longer experiments to be performed. This being undesirable from a practical viewpoint, there is a need for a parsimonious parameterization that would retain the benefits of high order ARX models. In this work, we propose to use generalized orthonormal basis filters (GOBFs) to achieve this parsimonous parameterization. Further, we propose an approach to obtain reduced order models by emphasizing important frequencies so as to suitably shape the bias. We also show that the choice of the GOBF parameterization has another important merit, viz. their ability to perform well even with minimal perturbation data or short experiment times. The efficacy of the proposed approach is demonstrated via simulations on the benchmark Shell Control Problem and a laboratory quadruple tank setup.  相似文献   
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