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991.
992.
Multi‐functional wireless sensor network (WSN) system is a new design trend of WSNs, which are evolving from dedicated application‐specific systems to an integrated infrastructure that supports the execution of multiple concurrent applications. Such system offers inherent advantages in terms of cost and flexibility because it allows the effective utilization of available sensors and resource sharing among multiple applications. However, sensor nodes are very constrained in resources, mainly regarding their energy. Therefore, the usage of such resources needs to be carefully managed, and the sharing with several applications imposes new challenges in achieving energy efficiency in these networks. In order to exploit the full potential of multi‐functional WSN systems, it is crucial to design mechanisms that effectively allocate tasks onto sensors so that the entire system lifetime is maximized while meeting various application requirements. However, it is likely that the requirements of different applications cannot be simultaneously met. In this paper, we present the Multi‐Application Requirements Aware and Energy Efficiency algorithm as a new resource allocation heuristic for multi‐functional WSN system to maximize system lifetime subject to various application requirements. The heuristic effectively deals with different quality of service parameters (possibly conflicting) trading those parameters and exploiting heterogeneity of multiple WSNs. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
993.

Introduction

Mortality of children with Severe Acute Malnutrition (SAM) in inpatient set-ups in sub-Saharan Africa still remains unacceptably high. We investigated the prevalence and effect of diarrhea and HIV infection on inpatient treatment outcome of children with complicated SAM receiving treatment in inpatient units.

Method

A cohort of 430 children aged 6-59 months old with complicated SAM admitted to Zambia University Teaching Hospital's stabilization centre from August to December 2009 were followed. Data on nutritional status, socio-demographic factors, and admission medical conditions were collected up on enrollment. T-test and chi-square tests were used to compare difference in mean or percentage values. Logistic regression was used to assess risk of mortality by admission characteristics.

Results

Majority, 55.3% (238/430) were boys. The median age of the cohort was 17 months (inter-quartile range, IQR 12-22). Among the children, 68.9% (295/428) had edema at admission. The majority of the children, 67.3% (261/388), presented with diarrhea; 38.9% (162/420) tested HIV positive; and 40.5% (174/430) of the children died. The median Length of stay of the cohort was 9 days (IQR, 5-14 days); 30.6% (53/173) of the death occurred within 48 hours of admission. Children with diarrhea on admission had two and half times higher odds of mortality than those without diarrhea; Adjusted OR = 2.5 (95% CI 1.50-4.09, P < 0.001). The odds of mortality for children with HIV infection was higher than children without HIV infection; Adjusted OR = 1.6 (95% CI 0.99-2.48 P = 0.5).

Conclusion

Diarrhea is a major cause of complication in children with severe acute malnutrition. Under the current standard management approach, diarrhea in children with SAM was found to increase their odds of death substantially irrespective of other factors.  相似文献   
994.
Deregulation of the electricity sector has given rise to several approaches to defining optimal portfolios of energy contracts. Financial tools - requiring substantial adjustments - are usually used to determine risk and return. This article presents a novel approach to adjusting the conditional value at risk (CVaR) metric to the mix of contracts on the energy markets; the approach uses Mixture Design of Experiments (MDE). In this kind of experimental strategy, the design factors are treated as proportions in a mixture system considered quite adequate for treating portfolios in general. Instead of using traditional linear programming, the concept of desirability function is here used to combine the multi-response, nonlinear objective functions for mean with the variance of a specific portfolio obtained through MDE. The maximization of the desirability function is implied in the portfolio optimization, generating an efficient recruitment frontier. This approach offers three main contributions: it includes risk aversion in the optimization routine, it assesses interaction between contracts, and it lessens the computational effort required to solve the constrained nonlinear optimization problem. A case study based on the Brazilian energy market is used to illustrate the proposal. The numerical results verify the proposal's adequacy.  相似文献   
995.
Triphenyltin (TPhT) is a biocide used worldwide in agriculture, especially in rice crop farming. The distribution and dissipation of TPhT in rice fields, as well as uptake of TPhT and other phenyltin compounds (monophenyltin, MPhT, and diphenyltin, DPhT) is still unknown at present. In this study, speciation analysis of phenyltin compounds was carried out in soil and water from a rice field where TPhT was applied during rice seeding according to legal application rates in Brazil. The results indicate the degradation of biocide and distribution of tin species into soil and water. To evaluate whether TPhT is taken up by plants, rice plants were exposed to three different TPhT application rates in a controlled mesocosm during 7 weeks. After this period, tin speciation was determined in soil, roots, leaves, and grains of rice. Degradation of TPhT was observed in soil, where DPhT and MPhT were detected. MPhT, DPhT, and TPhT were also detected in the roots of plants exposed to all TPhT application rates. Only TPhT was detected in leaves and at relatively low concentration, suggesting selective transport of TPhT in the xylem, in contrast to DPhT and MPhT. Concentration of phenyltin species in rice grains was lower than the limit of detection, suggesting that rice plants do not have the capability to take up TPhT from soil and transport it to the grains.  相似文献   
996.
The effects of mechanically deboned poultry meat (MDPM) and levels of collagen fibers on comminuted, cooked sausage quality characteristics were investigated using the central composite rotatable design of response surface methodology (RSM). Use of collagen fiber as an additive affected the sausage characteristics, but the effect depended on the amount of the MDPM used. While MDPM additions resulted in higher cooking loss and darker and redder frankfurters, the addition of collagen fibers improved cooking yields and contributed to the lightness of the final product. Higher collagen fiber content was also accompanied by a significant increase in frankfurter hardness regardless of the MDPM content. Use of collagen fibers countered the negative effects of MDPM on sausage quality attributes, especially on cooking yields and final product color.  相似文献   
997.
The main objective of this work was to understand which compounds are responsible for the partial inhibition of xanthohumol (XN) thermal isomerization during wort boiling of dark malts. With such purpose, worts from different kinds of malt (pale, caramel and roasted) were chemically characterized (e.g. antioxidant activity, polyphenols and melanoidins contents) and studied by several chromatographic techniques. Molecular exclusion chromatography experiments showed that adsorption of XN to polyvinylpolypyrrolidone is lower for the high molecular weight fractions. It seems likely that this is due to the reaction between XN and coloured substances that changes chemical properties of XN or, at least, results in the formation of complexes that have different chemical properties. This leads to an inhibition of XN isomerization observed in this work. It was also verified that the melanoidins content was significantly higher in the higher molecular weight fractions, suggesting that probably these compounds are the main responsible for the XN isomerization inhibiting effect.  相似文献   
998.
Foods rich in antioxidants play an essential role in the prevention of diseases. The present study compared contents of phenolics, vitamin C, anthocyanin and antioxidant activity of 11 fresh exotic fruits, cultivated in the northeastern part of Brazil. The antioxidant activities were evaluated using two antioxidant systems 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), expressed as TEAC (Trolox Equivalent Antioxidant Capacity) and VCEAC (Vitamin C Equivalent Antioxidant Capacity) values. The results indicated that the above fruits, such as murici and mangaba, were good sources of antioxidants. The phenolic contents showed positive correlations with total antioxidant by ABTS (R = 0.94, P ≤ 0.001) and DPPH (R = 0.88, P ≤ 0.001) assays. However, this correlation was not noticed when examining vitamin C and anthocyanins contents. The 11 fruits studied had comparable antioxidant activity in both, ABTS and DPPH assays. These methods are recommended as useful tools for the evaluation of the total activity antioxidant in fruits. Our results indicated promising perspectives for the development and usage of fruits species studied with considerable levels of antioxidant activity.  相似文献   
999.
Increasing trainees' multicultural counseling competence (MCC) has been a hot topic in counseling. Scholars have identified predictors (e.g., race/ethnicity, color-blindness) of MCC, and educators provide multicultural training for trainees. Using a sample of 370 psychology trainees, this study examined whether multicultural training (a) moderated racial/ethnic differences on MCC and (b) changed the relationship between color-blindness and MCC. Results indicated a significant interaction effect of race/ethnicity (i.e., White vs. ethnic minority) and multicultural training on multicultural awareness, but not on multicultural knowledge. Specifically, at lower levels of training, racial/ethnic minority trainees had significantly higher multicultural awareness than their White counterparts; at higher levels of training, no significant difference was found. Described differently, more training significantly enhanced Whites' multicultural awareness, but did not enhance racial/ethnic minority trainees' awareness. Additionally, there was a significant interaction effect of color-blindness and multicultural training on multicultural knowledge, but not on multicultural awareness. The association between color-blindness and multicultural knowledge was stronger at higher levels of multicultural training than at lower levels of training. Alternatively, the effect of training on enhancing knowledge was stronger for those with lower color-blindness than for those with higher color-blindness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
Enabling Heterogeneous Mobility in Android Devices   总被引:1,自引:1,他引:0  
The fast growing of mobile Internet users with the ability of using a wide diversity of access technologies such as Wi-Fi, WiMAX and UMTS/LTE, and the increasing proliferation of mobile devices with heterogeneous network interfaces, require versatile mobility mechanisms providing seamless roaming across those access technologies. Mobility agents such as Mobile IP and Fast MIPv6 are common, however, these solutions still have limitations when dealing with multiple link-layer technologies. In this context, the emerging standard IEEE 802.21 provides a framework which enables mobile agents and network operators to improve the handover process in heterogeneous networks. In this context, this paper presents and discusses the design and implementation of a mobility-aware solution for an Android device, using the IEEE 802.21 framework. A modified Android user terminal is proposed to improve the handover process, assuming a make-before-break approach. Resorting to an experimental testbed, the obtained results show that the proposed solution is an effective contribution to successfully accomplish seamless mobility of Android-based devices operating in 3G and Wi-Fi networks.  相似文献   
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