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51.
BACKGROUND: The nutritional status of children is a good indicator of the overall well-being of a society and reflects food security as well as existing health-care and environmental conditions. In Pakistan, it is estimated that nearly 40% to 50% of children under the age of five are stunted. Due to greater economic opportunities available to the urban population as compared to the rural, it was believed that economic resources existed in poor urban Pakistani households but that the households lacked the skills and knowledge to translate their resources into good care and feeding practices. OBJECTIVE: This study aimed 1) to assess the prevalent care and feeding practices among children aged 6 to 18 months residing in the squatter settlements of Karachi and 2) to identify care and feeding practices, as well as any other underlying factors, associated with stunting. METHODS: A cross-sectional survey was conducted in eight settlements between October and December 2000. A total of 433 mothers of eligible children were interviewed with the use of structured questionnaires. Final analysis using multiple logistic regression was conducted on 399 mother-child pairs. RESULTS: Female children were nearly three times more likely to be stunted than male children. Households that were food insecure with hunger were also three times more likely than other households to have a stunted child. Lack of maternal formal schooling (adjusted prevalence odds ratio, 2.9; 95% confidence interval, 1.4 to 3.8) and large household size (adjusted prevalence odds ratio, 1.7; 95% confidence interval, 1.0 to 3.8) were also associated with stunting. Even though certain care and feeding practices were significant at the univariate level, they were not significant in the final multivariate analysis and so were excluded from the final model. CONCLUSIONS: In households where food insecurity exists, knowledge of care practices may not be sufficient, and interventions such as food subsidies must precede or accompany educational efforts. Further follow-up is required to explore the effect of gender differences on child care.  相似文献   
52.
In this article, a novel fault ride-through technique has been implanted with a double control loop method. This method is implemented with voltage-source converters, where the active and reactive power could be easily done with the voltage control loop and inherent current control loop. The proposed system has been implemented to grid-connected photovoltaic systems, and the results have been explored and compared with the existing techniques. An additional control strategy is implemented successfully for satisfactory performance of the system during low irradiance periods, and the system is made capable to provide Q-support to the grid according to the system operators request with the help of Q-set point.  相似文献   
53.
Natural convection heat transfer from a heated cylinder contained in a square enclosure filled with water–Cu nanofluid is investigated numerically. The main objective of this study is to explore the influence of pertinent parameters such as Prandtl number (Pr) and diameter (D) of the heated body on the flow and heat transfer performance of nanofluids while Rayleigh number (Ra) and the solid particle volume fraction (?) of nanoparticle are considered fixed. The results obtained from finite element method clearly indicate that heat transfer augmentation is possible using highly viscous nanofluid resulting in the compactness of many industrial devices.  相似文献   
54.
Wireless Personal Communications - With the emergence of Internet of Things (IoT) having large scale and generating huge amount of data, Intelligent Decision Support Systems (IDSSs) have attracted...  相似文献   
55.
Multimedia Tools and Applications - Convolutional neural network (CNN) classification has not achieved a medically-satisfied level of accuracy in sleep apnea detection due to the negative effect of...  相似文献   
56.
Journal of Failure Analysis and Prevention - A number of wheel axles of MF-240 Tractors, which had broken after unusually short times in the field (~ 2–4 months), were examined to...  相似文献   
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58.
Conventional 3D woven T-shaped preforms were modified for improving joint/ peel off strength of associated T-shaped polymeric composites. Preforms were modified at weaving level by preferred yarns orientations for better performance in associated composites. Major modifications studied are; the addition of supporting layer, single or double-crossing in joint layers and crossing along with supporting layer (in a single sample). Novel derivatives were compared with conventionally used (on-loom and off-loom) T-shaped 3D woven composites. Microscopic analysis was also carried out to analyze the orientation of yarns and analysis of samples from failure point after testing. By combined variation of crossing and supporting layers improvement of 47.37% in peel off strength and 70.37% in impact strength was observed. Modified T shapes can serve to be a good replacement for conventional T-shaped stiffener (used to avoid folding under loads) and in joints.  相似文献   
59.
BACKGROUND: This work aims to investigate the effects of the common vinification steps on the fate of the ochratoxin A (OTA) during wine making. Two assays of red and rose microvinification, with artificially contaminated grapes, were performed. The content of this mycotoxin was also monitored throughout the process of red wine making from naturally contaminated grapes in a winery. RESULTS: The results from the different assays revealed that the maceration of pomace have a significant effect on the increase of OTA content in red wine (P < 0.05) whereas the alcoholic fermentation had a reducing effect. However, the spontaneous malolactic fermentation showed no significant effect on the OTA content in wine (P > 0.05). Storage of red wine in tanks followed by draining caused a significant decrease of OTA of about 55%. Clarification with a gelatin oenological fining agent contributed to the removal of up to 58% of OTA from red wine. CONCLUSION: Overall, a consistent decrease in OTA concentration was noticed throughout either red or rose vinification. This work has contributed to the understanding of the fate of OTA during different vinification processes, especially from naturally contaminated grapes. Copyright © 2008 Society of Chemical Industry  相似文献   
60.
This paper presents the updated long-term field performance data from the thermoplastic pipe deep burial study that the writers first initiated in the summer of 1999. The data from the past four to five years are presented in terms of pipe deflections and soil pressure measured at the pipe crown. Examinations of the historic field performance data revealed pipe-soil interaction behavior that had not been reported previously. The long-term pipe performance of both polyvinyl chloride and high density polyethylene pipes installed under at least 6.1?m (20?ft) of soil fill was characterized with nearly constant deflections/circumferential shortening and fluctuating soil pressures. Review of the long-term soil pressure data revealed some interesting trends regarding the relationships among pipe material type, pipe wall design, and fill height. Detailed review of the soil pressure data also led to a reasonable speculation that the seasonal fluctuations of environmental (air temperature, soil moisture) conditions caused the fluctuations in the peripheral soil pressure. Theoretical analysis based on the full-field elastic solutions showed that the temperature most likely had a much larger influence on the soil pressure fluctuations than the changes in the soil moisture conditions.  相似文献   
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