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31.
We reformulate the Quadratic Programming Feature Selection (QPFS) method in a Kernel space to obtain a vector which maximizes the quadratic objective function of QPFS. We demonstrate that the vector obtained by Kernel Quadratic Programming Feature Selection is equivalent to the Kernel Fisher vector and, therefore, a new interpretation of the Kernel Fisher discriminant analysis is given which provides some computational advantages for highly unbalanced datasets. 相似文献
32.
A. Dalla Marta M. Mancini R. Ferrise M. Bindi S. Orlandini 《Biomass & bioenergy》2010,34(7):1041-1052
The possibility of using biomass as a source of energy in reducing green-house gas emissions is a matter of great interest. In particular, biomasse from agriculture represent one of the largest and most diversified sources to be exploited and more specifically, ethanol and diesel deriving from biomass have the potential to be a sustainable means of replacing fossil fuels for transportation. Nevertheless, the cultivation of dedicated energy crops does meet with some criticism (competitiveness with food crop cultivation, water requirements, use of fertilizers, etc.) and the economical and environmental advantages of this activity depend on accurate evaluations of the total efficiency of the production system. This paper illustrates the production potential of two energy crops, sunflower (Helianthus annuus) and maize (Zea mais), cultivated with different water and fertilization supplies in the region of Tuscany, in central Italy. A 50-year climatic series of 19 weather stations scattered around Tuscany was used to run the crop model CropSyst for obtaining crop biomass predictions. The effect of climate change and variability was analyzed and the potential production of bioenergy was investigated in terms of pure vegetable oil (sunflower) and bioethanol (maize). The results demonstrated that despite a reduction in crop yields and an increase of their variability due to climate change, the cultivation of maize in the regional set-aside areas would be capable of supplying approximately 50% of the energy requirements in terms of biofuel for transportation obtained, while the cultivation of a sunflower crops would supply less than 10%. 相似文献
33.
Biomass and Sterol Production from Vegetal Substrate Fermentation Using Agaricus brasiliensis
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34.
U. TylewiczP.J. Fito M. Castro-GiráldezP. Fito M. Dalla Rosa 《Journal of food engineering》2011,104(3):438-444
Shelf life of kiwifruit is short and requires conservation techniques to increase its commercial life. In this sense, the modern techniques used to analyze the changes of the product through the treatment allow developing new products with the specific quality characteristics required. In this work, the structural and physico-chemical changes of kiwifruit through the osmotic dehydration treatment with 61.5% (w/w) sucrose solution at short times from 0 to 300 min were explained.The SAFES (systematic approach to food engineering systems) methodology applied in kiwifruit is useful to obtain the internal composition of each phase, to control the fruit changes through the process, and to determine the behaviors involved in transports. Moreover, the Gibbs free energy, the enthalpy and the entropy estimation of each phase was calculated in order to analyze the irreversibility of the process. 相似文献
35.
Santa I. Kozma L. Nemet B. Hebling J. Gorbal M. 《Quantum Electronics, IEEE Journal of》1986,22(11):2174-2180
We have studied the capacitor transfer type of flat-plate-transmission-line traveling wave excited atmospheric pressure nitrogen laser. Experiments were carried over a wide variety of parameters such as charging voltage, separation and angle of electrodes, capacitance of bank, inductance of switching circuit, and geometrical parameters of resonators. The theory is based upon the macroscopic properties of nitrogen discharges. Laser pulses were calculated by solving numerically the space-dependent rate equations for population and photon number densities. The theoretical predictions are in very good agreement with the experimental observations. 相似文献
36.
A Piattelli A Scarano A Dalla Nora G De Bona GA Favero 《Canadian Metallurgical Quarterly》1998,19(7-9):643-649
The authors present a histologic analysis of 19 Branemark titanium implants retrieved for different causes: four implants were removed for abutment fracture, one for dental nerve dysesthesia, two for bone overheating, two for peri-implantitis, nine for mobility, one for unknown causes. In the implants removed for fracture a high bone-implant contact percentage was present (71.83 +/- 4.96%) with compact, mature bone at the interface. The picture of the failure due to bone overheating was characteristic with the presence of bone sequestra and of a gap between implant and bone filled by lymphocytes and plasma cells: many bacteria surrounded the necrotic bone and no newly regenerated bone was present. In peri-implantitis an inflammatory infiltrate was observed in the peri-implant tissues: a dense fibrous connective tissue was present around implants failed for mobility. The microscopical picture is certainly extremely important in identifying the causal determinants of an implant failure. 相似文献
37.
Cludio Dariva Humberto Lovisi Luis C. Santa Mariac Fernanda M. B. Coutinho Jos Vladimir Oliveira Jos Carlos Pinto 《加拿大化工杂志》2003,81(1):147-152
Propylene solubility in toluene and isododecane (2,2,4,6,6‐Pentamethylheptane, CA Registry# 13475‐82‐6) was measured at different temperatures and pressures, similar to the ones normally used to carry out propylene polymerizations through metallocene and Ziegler‐Natta catalysts. Experimental data were obtained with a gravimetric method, where experimental liquid phase compositions are measured at known temperature and pressure conditions. The experimental data were modeled with two different models: the Wilson excess Gibbs free energy model and an empirical model. Both modeling approaches may be recommended for analysis of kinetic data obtained for slurry propylene polymerizations in toluene and isododecane. 相似文献
38.
High temperature treatment under vacuum or in a pure N2 atmosphere can be used instead of a reduction step to activate Cr/SiO2 catalysts used for ethylene polymerization. After this procedure, the Cr species active over a range of temperature has been identified as Cr(III) using CO adsorption (IR triplet bands at 2228, 2214, and 2202 cm–1) and an ethylene polymerization activation energy of 12.1 kcal/mol. The Cr(III) species has also been shown to be present after activation using CO reduction, the more commonly used procedure. Cr(II) sites are always present when activation involves reduction with CO and become increasingly active as the temperature rises above room temperature. 相似文献
39.
The amino acid sequences of two ribonucleases from a callus cell culture of Panax ginseng were determined. The two sequences differ at 26% of the amino acid positions. Homology was found with a large family of intracellular pathogenesis-related proteins, food allergens and tree pollen allergens from both dicotyledonous and monocotyledonous plant species. There is about 30% sequence difference with proteins from species belonging to the same plant order (Apiales: parsley and celery), 60% with those from four other dicotyledonous plant orders and about 70% from that of the monocotyledonous asparagus. More thorough evolutionary analyses of sequences lead to the conclusion that the general biological function of members of this protein family may be closely related to the ability to cleave intracellular RNA and that they have an important role in cell metabolism. As the three-dimensional structure of one of the members of this protein family has been determined recently [Gajhede et al., Nature Struct Biol 3 (1996) 1040-1045], it may be possible to assign active-site residues in the enzyme molecule and make hypotheses about its mode of action. Structural features in addition to the cellular site of biosynthesis indicate that this family of ribonucleases is very different from previously investigated ones. 相似文献
40.
F Serafini G Vescovo L Dalla Libera C Catani L Facchin PL Tenderini R Zennaro C Leprotti GB Ambrosio 《Canadian Metallurgical Quarterly》1997,42(9):941-946
Chronic heart failure (CHF) is accompanied by a reduced exercise capacity, and the symptoms can be at least in part explained by qualitative and quantitative changes in the skeletal muscle composition and metabolism. We have correlated the myosin heavy chain (MHC) composition of the gastrocnemius in 20 patients with different degrees of CHF to expiratory gases measured during maximal cardiopulmonary exercise testing, NYHA functional class and echocardiographic parameters. MHC composition was determined electrophoretically in skeletal muscle needle microbiopsies and the percent distribution calculated by laser densitometry. There was no correlation between ejection fraction, left ventricular end-diastolic and end-systolic diameters and MHC composition. The percentage of MHC 1 (slow aerobic isoform) was positively correlated with peak VO2 (r2 = 0.5, p = 0.0004), ventilatory threshold (VT, r2 = 0.33, p = 0.008), and O2 pulse (peak VO2/HR, r2 = 0.40, p = 0.003). There was a negative correlation between MHC 2a and 2b (fast isoforms) and peak VO2 (r2 = 0.38 and 0.37, p = 0.004, respectively), VT (r2 = 0.2, p = 0.05; r2 = 0.34, p = 0.007, respectively) and O2 pulse (r2 = 0.39, p = 0.003; r2 = 0.23, p = 0.03, respectively). NYHA functional class was also negatively correlated with the same parameters (r2 = 0.2, p = 0.01; r2 = 0.4, p = 0.001; r2 = 0.34, p = 0.006, respectively) as well as with MHC 1 (r2 = 0.62, p = 0.0001). A positive correlation was found between NYHA functional class and MHC 2a and 2b (r2 = 0.46, p = 0.001; r2 = 0.41, p = 0.002, respectively). The severity of heart failure is paralleled by a shift of the MHC pattern toward the fast MHC 2b. The correlation between the magnitude of the MHCs shift, from the slow aerobic to the fast type, with both clinical parameters (NYHA functional class) and functional measurements (peak VO2, VT, O2 pulse) of exercise capacity seem to suggest that changes in skeletal muscle composition may play a key role in exercise tolerance in patients with CHF. 相似文献