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31.
32.
Our work concerns the design of robust information retrieval environments that can successfully handle queries containing misspelled words. Our aim is to perform a comparative analysis of the efficacy of two possible strategies that can be adopted.  相似文献   
33.
To study the mechanism of action of water soluble compound GII purified from fenugreek (Trigonella foenum graecum) seeds which was shown earlier to have antidiabetic effect in the subdiabetic, moderately and severely diabetic rabbits. In rabbits (1–1.5 kg bw) diabetes was induced by intravenous injection of 80 mg/kg bw of alloxan. They were fed with GII at a dose of 50 mg/kg bw daily once in the morning for 15 days in the subdiabetic and moderately diabetic and 30 days in the severely diabetic rabbits. Serum total cholesterol (TC), triglycerides (TG), LDL + VLDL cholesterol [(LDL + VLDL)C], HDL cholesterol [(HDL)C], total tissue lipids, glycogen and enzymes of carbohydrate metabolism (glycolysis, gluconeogenesis, polyol pathway) hexokinase, glucokinase, pyruvate kinase, malic enzyme, glucose-6-phosphatase, glucose-6-phosphate dehydrogenase, aldose reductase and sorbitol dehydrogenase and antioxidant enzymes glutathione peroxidase, glutathione reductase and superoxide dismutase were estimated. Liver and kidney function parameters were also estimated. Treatment with GII for 15 days in the subdiabetic and moderately diabetic rabbits and for 30 days in the severely diabetic rabbits (i) decreased the elevated lipids TC, TG, (LDL + VLDL)C and increased the decreased (HDL)C, (ii) decreased the elevated liver and heart total lipids, TC and TG, (iii) increased the decreased liver and muscle glycogen, (iv) increased the decreased hexokinase, glucokinase, pyruvate kinase, malic enzyme, glucose-6-phosphate dehydrogenase, superoxide dismutase, glutathione peroxidase, (v) decreased the increased glucose-6-phosphatase, sorbitol dehydrogenase, aldose reductase. Results thus show that treatment with GII compound purified from fenugreek seeds for 15 days in the subdiabetic and moderately diabetic and 30 days in the severely diabetic rabbits corrects the altered serum lipids, tissue lipids, glycogen, enzymes of glycolysis, gluconeogenesis, glycogen metabolism, polyol pathway and antioxidant enzymes. Histopathological abnormalities (fatty infiltration and other cellular changes) seen in the pancreas, liver, heart and kidneys were repaired after treatment with GII. In fact partially damaged pancreas was repaired. Liver and kidney function test results were normal in the GII treated animals indicating that GII treatment is safe and free from any side effects.  相似文献   
34.
The dynamics of the impact and coalescence of droplets on a solid surface   总被引:1,自引:0,他引:1  
A simple experimental setup to study the impact and coalescence of deposited droplets is described. Droplet impact and coalescence have been investigated by high-speed particle image velocimetry. Velocity fields near the liquid-substrate interface have been observed for the impact and coalescence of 2.4 mm diameter droplets of glycerol∕water striking a flat transparent substrate in air. The experimental arrangement images the internal flow in the droplets from below the substrate with a high-speed camera and continuous laser illumination. Experimental results are in the form of digital images that are processed by particle image velocimetry and image processing algorithms to obtain velocity fields, droplet geometries, and contact line positions. Experimental results are compared with numerical simulations by the lattice Boltzmann method.  相似文献   
35.
This paper proposes a new sliding mode observer for fault reconstruction, applicable for a class of linear parameter varying (LPV) systems. Observer schemes for actuator and sensor fault reconstruction are presented. For the actuator fault reconstruction scheme, a virtual system comprising the system matrix and a fixed input distribution matrix is used for the design of the observer. The fixed input distribution matrix is instrumental in simplifying the synthesis procedure to create the observer gains to ensure a stable closed-loop reduced order sliding motion. The ‘output error injection signals’ from the observer are used as the basis for reconstructing the fault signals. For the sensor fault observer design, augmenting the LPV system with a filtered version of the faulty measurements allows the sensor fault reconstruction problem to be posed as an actuator fault reconstruction scenario. Simulation tests based on a high-fidelity nonlinear model of a transport aircraft have been used to demonstrate the proposed actuator and sensor FDI schemes. The simulation results show their efficacy.  相似文献   
36.
Over the last few years, information and communication technologies have become an essential part of daily life, affecting education, employment, and leisure, among other activities. Nonetheless, many individuals still reap few or no benefits from these technologies, and there are resilient gaps in their use. Within this larger context, the authors examine the Internet digital divide between people with and without disabilities from a multidimensional approach. Rather than analyzing the gap in terms of “haves” and “have-nots,” a range of Internet-related dimensions—affordability, motivation and attitudes, skills, usage, and others—is taken into account.  相似文献   
37.
Although the importance of intellectual capital has already been highlighted in the management literature, few articles have focused on the importance of its green counterpart, green intellectual capital. Nowadays, when environmental concerns cannot be ignored by firms, it is therefore time to explore the role of green intellectual capital in environmental improvement. For that reason, our research aims to explore the relationships between green intellectual capital components and the environmental performance of the firms. In particular, we try to show the importance of green organizational and social capital in the development of environmental product innovations, which are vital to the development and implementation of environmental strategies since, as scholars have pointed out, they generate some of the greatest environmental impacts. The empirical results show that green organizational capital has an indirect impact on environmental product innovation through green social capital, meaning that the latter is a significant mediator of that relationship, and at the same time emphasizing that informal relationships play a key role in the improvement of the environmental performance of the firm and, more specifically, in the development of environmental product innovations.  相似文献   
38.
This study examines the role of regional government quality in health-related participation in sport and physical activity among adults (18–64 years) in 28 European countries. The importance of the analysis rests in the relative autonomy that regional and local governments have over policy decisions connected with sport and physical activity. While existing studies have focussed on economic and infrastructural investment and expenditure, this research investigates the quality of regional governments across 208 regions within 28 European countries. The individual-level data stem from the 2013 Eurobarometer 80.2 (n?=?18,675) and were combined with regional-level data from Eurostat. An individual's level of participation in sport and physical activity was measured by three variables reflecting whether an individual's activity level is below, meets, or exceeds the recommendations of the World Health Organization. The results of multi-level analyses reveal that regional government quality has a significant and positive association with individual participation in sport and physical activity at a level meeting or exceeding the guidelines. The impact is much larger than that of regional gross domestic product per capita, indicating that regional disadvantage in terms of political quality is more relevant than being disadvantaged in terms of economic wealth.  相似文献   
39.
Content analyses of prime-time television provide a picture of predominant cultural stereotypes and social trends. The present research is a quantitative content analysis of social class in popular broadcast and cable television in the United States. This research advances scholarship by systematically analyzing character class in addition to more commonly examined variables such as race and gender. A model for the operationalization of class for quantitative content analyses of mediated texts is offered. This proof of concept study demonstrates the viability of studying media representations of class quantitatively to systematically document patterns of portrayal.  相似文献   
40.
Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents.  相似文献   
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