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1.
Hundreds of millions of users each day submit queries to the Web search engine. The user queries are typically very short which makes query understanding a challenging problem. In this paper, we propose a novel approach for query representation and classification. By submitting the query to a web search engine, the query can be represented as a set of terms found on the web pages returned by search engine. In this way, each query can be considered as a point in high-dimensional space and standard classification algorithms such as regression can be applied. However, traditional regression is too flexible in situations with large numbers of highly correlated predictor variables. It may suffer from the overfitting problem. By using search click information, the semantic relationship between queries can be incorporated into the learning system as a regularizer. Specifically, from all the functions which minimize the empirical loss on the labeled queries, we select the one which best preserves the semantic relationship between queries. We present experimental evidence suggesting that the regularized regression algorithm is able to use search click information effectively for query classification.  相似文献   
2.
Electric vehicles (EVs) are becoming increasingly popular because of their low operating costs. However, the anticipated increase in EV usage presents opportunities as well as challenges for utilities. This paper models EV charging behavior of active consumers who strategize their EV charging schedule to minimize the charging cost. The electric utility employs a temporal and spatially varying real-time pricing scheme that minimizes peak-to-average load ratio by influencing charging behavior of multiple active consumers. These active consumers decide their optimal charging strategy based on real-time electricity prices in order to minimize their EV charging cost. A model predictive control (MPC)-based optimal pricing scheme for electric utility and optimal charging strategy for active consumers is proposed. Effects of the proposed approach on load profile is verified using simulations.  相似文献   
3.
The homeobox protein STF-1 appears to function as a master control switch for expression of the pancreatic program during development. Here we characterize a composite enhancer which directs STF-1 expression to pancreatic islet cells via two functional elements that recognize the nuclear factors HNF-3beta and BETA-2. In keeping with their inhibitory effects on islet cell maturation, glucocorticoids were found to repress STF-1 gene expression by interfering with HNF-3beta activity on the islet-specific enhancer. Overexpression of HNF-3beta suppressed glucocorticoid receptor-mediated inhibition of the STF-1 gene, and our results suggest that the expansion of pancreatic islet precursor cells during development may be restricted by hormonal cues which regulate STF-1 gene expression.  相似文献   
4.
Jhala E  Galilee C  Reinisch L 《Applied optics》2007,46(22):5522-5528
We have measured the autofluorescence from suspensions of Pseudomonas aeruginosa in the growth medium and after one, two, and three washes. The bacterium was grown in two different media, nutrient broth and King's B broth. The bacterium was harvested after 12, 24, and 48 h of growth. The fluorescence was measured with excitation every 10 nm from 200 nm to 600 nm. The fluorescence profiles were analyzed using principal component analysis. We found that most of the information is in the first three principal components. Stark differences in the value of the first principal component were noted between the samples in broth and those with one, two, or three washings. The second and third principal components noted differences between the samples washed once and those washed two or three times. There was no significant difference between samples washed two and three times. There are small differences noted between the samples grown in the two different broths, and no differences were noted among the samples harvested at different times.  相似文献   
5.
Although eradication of Helicobacter pylori cures duodenal ulcer, some patients are not infected and others are treatment failures. This randomized, double-blind, placebo-controlled study assessed the value of treatment with low-dose lansoprazole in preventing duodenal ulcer recurrence. One hundred eighty-six patients with endoscopic documentation of healed duodenal ulcer received 15 mg/day lansoprazole or placebo for 12 months or until ulcer recurred. Endoscopy results, symptom assessment, and fasting serum gastrin levels were obtained at multiple time points. Densities of E, EC, and G cells were assessed by biopsy when the ulcer recurred or at the final visit. Time to ulcer recurrence was significantly longer (P < 0.001) in the lansoprazole group (median >12 months) compared to placebo (median <3 months), and patients taking lansoprazole were asymptomatic longer (P < 0.05). Maintenance therapy with lansoprazole 15 mg/day suppresses acid and controls recurrence of duodenal ulcer disease.  相似文献   
6.
The ruthenium(II) complexes with 2,9-dimethyl-1,10-phenanthroline (dmphen) and terpyridine derivatives have been synthesized and screened for their antimicrobial potency. The interaction of these complexes with Herring Sperm DNA was investigated by thermal denaturation, viscosity measurements, gel electrophoresis and spectrophotometric methods. The results indicate that the complexes bound to DNA via partial intercalative mode. The salt-dependent binding of these complexes has been determined by UV–Vis spectrophotometric titration. The contribution of the non-electrostatic binding free energy (ΔGto) to the total binding free energy change (ΔGo) is found to be ~ 88% at [Na+] = 0.075 M. The large value suggests that the stabilization of the DNA binding is mostly due to the contribution of non-electrostatic process.  相似文献   
7.
In the present work, a multiobjective heat transfer search (MOHTS) algorithm is proposed and investigated for thermo‐economic and thermodynamic optimization of a plate–fin heat exchanger (PFHX). Heat exchanger effectiveness and total annual cost (TAC) are considered as thermo‐economic objective functions. Similarly, entropy generation rate and heat exchanger effectiveness are considered as thermodynamic objective functions. Six design variables including flow length of cold and hot streams, no flow length, fin height, fin pitch, and fin offset length are considered as decision variables. Effectiveness and accuracy of the proposed algorithm are evaluated by analyzing application examples of a PFHX. The results obtained using the proposed algorithm for thermo‐economic considerations are compared with the available results of NSGA‐II and TLBO in the literature. Results show that 3.56% to 10.29% reductions in TAC with 0.48% to 0.81% higher effectiveness are observed using the proposed approach compared to TLBO and NSGA‐II approaches. Additionally, the distribution of each design variable in its allowable range is also shown for thermo‐economic consideration to identify the level of conflict on objective functions. The sensitivity analyses of design variables on the objective functions value are also performed in detail.  相似文献   
8.
The software model checker Blast   总被引:2,自引:0,他引:2  
Blast is an automatic verification tool for checking temporal safety properties of C programs. Given a C program and a temporal safety property, Blast either statically proves that the program satisfies the safety property, or provides an execution path that exhibits a violation of the property (or, since the problem is undecidable, does not terminate). Blast constructs, explores, and refines abstractions of the program state space based on lazy predicate abstraction and interpolation-based predicate discovery. This paper gives an introduction to Blast and demonstrates, through two case studies, how it can be applied to program verification and test-case generation. In the first case study, we use Blast to statically prove memory safety for C programs. We use CCured, a type-based memory-safety analyzer, to annotate a program with run-time assertions that check for safe memory operations. Then, we use Blast to remove as many of the run-time checks as possible (by proving that these checks never fail), and to generate execution scenarios that violate the assertions for the remaining run-time checks. In our second case study, we use Blast to automatically generate test suites that guarantee full coverage with respect to a given predicate. Given a C program and a target predicate p, Blast determines the program locations q for which there exists a program execution that reaches q with p true, and automatically generates a set of test vectors that cause such executions. Our experiments show that Blast can provide automated, precise, and scalable analysis for C programs.  相似文献   
9.
A cardinal feature of malaria, splenomegaly, is usually absent in adult patients who have already suffered from falciparum malaria or who are natives of an endemic falciparum zone. This is an attribute of the past episode of clinical or sub-clinical malaria which usually results in regression of the splenic size to below-normal. An ultrasonographic evaluation of spleens was done in 90 healthy adult males, who had suffered from vivax (n = 28) or falciparum (n = 25) malaria in the past, except the controls (n = 22) and natives from an endemic falciparum area (n = 15) who never suffered from malaria. Their ultrasonographic details of spleens, including the size, were compared. Besides other conspicuous differences in the ultrasonographic picture, spleen size was found significantly decreased (p < 0.01) in the group who had been affected by P. falciparum malaria; the smallest measured 7.8 cms. In P. vivax group the decrease was not significant (p < 0.1), but was highly significant in inhabitants of endemic falciparum region (p < 0.001). The present study establishes the 'Small Spleen' and looks at echotexture pattern variations thereof for the first time.  相似文献   
10.
Information about interactive virtual environments, such as games, is perceived by users through a virtual camera. While most interactive applications let users control the camera, in complex navigation tasks within 3D environments users often get frustrated with the interaction. In this paper, we propose inclusion of camera control as a vital component of affective adaptive interaction in games. We investigate the impact of camera viewpoints on psychophysiology of players through preference surveys collected from a test game. Data is collected from players of a 3D prey/predator game in which player experience is directly linked to camera settings. Computational models of discrete affective states of fun, challenge, boredom, frustration, excitement, anxiety and relaxation are built on biosignal (heart rate, blood volume pulse and skin conductance) features to predict the pairwise self-reported emotional preferences of the players. For this purpose, automatic feature selection and neuro-evolutionary preference learning are combined providing highly accurate affective models. The performance of the artificial neural network models on unseen data reveals accuracies of above 80% for the majority of discrete affective states examined. The generality of the obtained models is tested in different test-bed game environments and the use of the generated models for creating adaptive affect-driven camera control in games is discussed.  相似文献   
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