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101.

Knowledge building is an important activity taken up by various organizations. The paper exemplifies the creation of a knowledge-centric environment for a non-profit sector such as a higher education. Building knowledge and thereafter using it are important aspects of knowledge-centric environment; this further helps the organization to gain competitive advantage. With the increase in popularity of genetic algorithm (GA), the technique has been used in building efficient classifiers for creating effective rule sets. The paper makes use of multi-objective genetic algorithm for building GA-based efficient classifier because classification rule mining is itself, a multi-objective problem. Knowledge expressed through classification rules help in establishing relationships between attributes that are not visible openly. The study assumes importance as curriculum planning is an important aspect of any academic institution, the knowledge derived in the form of rules residing in the knowledge base help to substantiate proper curriculum development, making a sizeable contribution toward professional growth and advancement of the students. On implementation of the findings, educational organizations will be able to institute themselves as knowledge centric.

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102.
Postharvest browning of Agaricus mushrooms is a severe problem that reduces the shelf life of harvested mushrooms because of their continued respiration and biochemical activity. There are no simple answers and no single treatment is known to limit overall quality deterioration. However, there are several strategies that are being implemented in order to reduce the rate of respiration for mushrooms. Packaging technology is the common denominator that allows us to implement these strategies and thus is key to quality preservation. In this review, first, the major factors involved in postharvest quality deterioration are discussed and then technological advances/methods used to counteract these hurdles are presented. Copyright © 2010 Society of Chemical Industry  相似文献   
103.
Watermelon (Citrullus lanatus) seed meal contains significant amount of extractable protein which can be used as nutritional and functional ingredients in food formulations. Alkali (0.1 M) and NaCl (0.5 M) were used to prepare protein isolates and concentrates from the defatted watermelon seed meals. Protein isolates reported protein yield of 35.15–38.27% and protein content (79.05–83.79%) which was significantly (p≤0.05) higher than the protein concentrates. SDS-PAGE of protein isolates and concentrates showed major polypeptides in the range of 74.72–110.42 kDa. Also, in vitro pepsin digestibility showed that most of the proteins were readily digested within 30 min of hydrolysis. Amino acids were dominated by arginine, aspartic, and glutamic acid. DSC results indicated that protein concentrates had significantly (p≤0.05) higher denaturation temperatures than protein isolates. The functional properties of concentrates in terms of solubility and surface properties were better than respective isolates. The results indicated that NaCl extracted proteins had comparatively better functional properties but their yield is significantly lower than respective protein isolates.  相似文献   
104.
Biofabrication of noble monometallic platinum nanoparticles(Pt-NPs) and bimetallic gold–silver nanoparticles(Au Ag-NPs) using aqueous extract of Delonix regia is presented here. Antioxidant activity of biomatrix-loaded metallic nanoparticles is estimated for scavenging of two model radicals i.e., 2,2′-Azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt and 1,1′-Diphenyl-2-picrylhydrazyl. Broad spectral continuum spanning from visible to ultra-violet region(Pt-NPs: 30 min) and broad high intensity absorption peak around at 500 nm(Au Ag-NPs: 10 min) in two different UV–Visible spectra confirmed the biofabrication. Nanoparticles fabricated with distorted spherical shape and crystalline face-centred-cubic geometry. Strong signal around at 2.10 ke V(pure-phase platinum) and typical X-ray peaks observed at 2.20 and 3 ke V suggested, co-existence and alloying interaction of Au and Ag in Au Ag-NPs. ζ potential(-15.2 mV: Pt-NPs and -13.9 mV: Au Ag-NPs) values suggested surface adsorption of polyphenolic compounds to provide stability. Nanoparticles exhibited pronounced antioxidant activity against free radicals through their electron/hydrogen transfer ability.  相似文献   
105.
The work addresses the preparation of Ni3P3TiO2 nanocomposite coatings on mild steel substrate by the electroless technique. Nanosized TiO2 particles were first synthesized by the precipitation method and then were codeposited (4 g/l) into the Ni3P matrix using alkaline hypophosphite reduced EL bath. The surface morphology, particle size, elemental composition and phase analysis of as-synthesized TiO2 nanoparticles and the coatings were characterized by field emission scanning electron microscopy (FESEM), energy-dispersive analysis of X-ray (EDAX) and X-ray diffraction (XRD). Coatings with 20 µm thickness were heat treated at 400 °C for 1 h in argon atmosphere. The morphology, microhardness, wear resistance and friction coefficient characteristics (ball on disc) of electroless Ni3P3TiO2 nanocomposite coatings were determined and compared with Ni3P coatings. The results show that as-synthesized TiO2 nanoparticles are spherical in shape with a size of about12 nm. After heat treatment, the microhardness and wear resistance of the coatings are improved significantly. Superior microhardness and wear resistance are observed for Ni3P3TiO2 nanocomposite coatings over Ni3P coatings.  相似文献   
106.
Browsing is part of the information-seeking process, used when information needs are ill-defined or unspecific. Browsing and searching are often interleaved during information seeking to accommodate changing awareness of information needs. Digital libraries often do not support browsing. Described here are three browsing systems created for the Greenstone digital library software .  相似文献   
107.
We have indigenously developed a twenty-stage vertical structure type Marx generator. At a matched load of 90–100 Ω, for 25 kV DC charging, an output voltage pulse of 230 kV, and duration 150 ns is obtained. This voltage pulse is applied to a relativistic electron beam (REB) planar diode. For a cathodeanode gap of 7.5 mm, an REB having beam voltage 160kV and duration 150ns is obtained. Brass as well as aluminum explosive electron emission-type cathodes have been used  相似文献   
108.
This paper targets to present energy efficient high speed true single phase clock dynamic circuit design technique, utilizing a novel body biasing tuner. The threshold voltage is controlled dynamically by dint of a novel body bias tuner so that performance of the circuit is enhanced in terms of power, delay, temperature, voltage, noise and corner variations. Power consumption and delay is computed and analysed for wide range of temperature and 40.78–95.5% saving in power delay product is obtained with the same. Quantification of bias voltage variation effect and process corners to find the effectiveness of the proposed design are examined and it is found to be performing consistently as compared with other techniques. Later on bouncing noise analysis is done for the valuation of noise in the circuit. Comparison of power delay product, transistor count and clock phase is done with several previously reported designs. Comprehensive simulation in cadence using 90 nm technology, shows that the proposed design vanquish conventional and other previously reported dynamic circuit design techniques in all aspect of circuit performance. Further, an arithmetic logic unit for measurement using sensors is implemented as a prolongation of the proposed dynamic circuit design technique.  相似文献   
109.
In the present study, the effect of bioaugmentation with three bacterial species (i.e. E. coli, Bacillus subtilis and Enterobacter aerogenes) on the hydrogen production from organic fraction of municipal solid waste was evaluated at different bacteria/sludge ratios (0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35 and 0.40). Cumulative hydrogen production, lag phases, and maximum hydrogen production rates were analyzed using modified Gompertz model. The highest cumulative and volumetric hydrogen production of 564.4 ± 10.9 mL and 1.61LH2/Lsubstrate respectively was achieved for bioaugmentation with Bacillus subtilis at bacteria/sludge ratio of 0.25. The corresponding highest hydrogen yield was 43.68 mLH2/gCarbo. For bioaugmentation with E. coli and Enterobacter aerogenes, the maximum cumulative hydrogen production of 423.4 ± 10.6 mL and 486.3 ± 10.6 mL respectively was obtained from bacteria/sludge ratio of 0.20. Corresponding highest hydrogen yields were 32.9 mLH2/gCarbo and 37.1 mLH2/gCarbo respectively. Bioaugmentation shortened the lag phases and improved COD removal. Volatile fatty acid generation was also improved with the bioaugmentation.  相似文献   
110.
BACKGROUND: People in developing countries depend largely on non‐conventional protein sources to augment the availability of proteins in their diets. Watermelon seed meal is reported to contain an adequate amount of nutritional proteins that could be extracted for use as nutritional ingredients in food products. RESULTS: Osborne classification showed that globulin was the major protein (≥500 g kg ?1) present in watermelon seed meal, followed by albumin and glutelin. Sodium dodecyl sulfate polyacrylamide gel electrophoresis indicated that the polypeptides had low molecular weights ranging from 35 to 47 kDa. Isoelectric focusing revealed that the isoelectric point of most proteins was in the acidic range 4–6. These proteins are rich in aspartic acid, glutamic acid and serine. An increase in pH (5–9) significantly (P < 0.05) decreased the denaturation enthalpy of these proteins. Among functional properties, albumin exhibited a much higher dispersibility index (810.3–869.6 g kg?1) than globulin (227.8–245.4 g kg?1), glutelin (182.1–187.7 g kg?1) and prolamin (162.3–177.7 g kg?1). Digestibility was in the ranges 760.6–910.0 and 765.5–888.5 g kg?1 for Mateera and Sugar Baby watermelon protein fractions respectively, while surface hydrophobicity ranged from 126.4 to 173.2 and from 125.8 to 169.3 respectively. The foaming and emulsifying properties of albumin were better than those of the other proteins studied. CONCLUSION: The good nutritional and functional properties of watermelon seed meal proteins suggest their potential use in food formulations. Copyright © 2010 Society of Chemical Industry  相似文献   
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