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991.
Book reviews     
Australian Environmental Policy 2: Studies in Decline and Devolution

Ken Walker and Kate Crowley (eds) UNSW Press, Sydney, 1999 ISBN 0868406732 (paperback) 323 pp.; bibliography and index RRP $35.00

Beyond Meltdown: The Global Battle for Sustained Growth.

Peter Brain. Scribe, Melbourne, 1999 ISBN 0908011369 (paperback) 273 pp.; bibliography and index RRP $26.95

Cities Back from the Edge: New Life for Downtown

Roberta Brandes Gratz with Norman Mintz John Wiley & Sons, New York, 1998 ISBN 0471144177 (hardback) 347 pp.; index RRP $59.95

Evaluation in Planning: Facing the Challenge of Complexity

Nathaniel Lichfield, Angela Barbanente, Dino Bori, Abdul Khakee and Anna. Prat (eds). Kluwer, Dordrecht, 1998. ISBN 0792351770 (hardback). 383 pp.; index. RRP $254.00

Gritty Cities: Images of the Urban

Lyaranette Finch and Chris McConville (eds). Pluto, Sydney, 1999. ISBN 1864030631 (paperback). 250 pp.; bibliography and index. RRP $24.95

Setting the Stage for Systainability: A Citizen's Handbook

Chris Maser, Russ Beaton and Kevin Smith Lewis Publishers, Boca Raton, 1998 ISBN 1574441876 (hardback) 269 pp.; index RRP $47.50

The Australian Metropolis: A Planning History

Stephen Hamnett and Robert Freestone (eds) Allen & Unwin, Sydney, 1999 ISBN 1865080535 (paperback) 229 pp.; index RRP $35.00  相似文献   
992.
Exploratory Analytics is the process of analyzing data for the purpose of forming hypotheses. Patent data sets, because they are relatively large and diverse and because they consist of a mixture of structured and unstructured information present a formidable challenge and a great opportunity in applying exploratory analytics techniques. In this paper we describe methods we have implemented for effective exploratory analytics on patent data sets using an interactive approach and a web based software tool called SIMPLE. We use real-world case studies to demonstrate the effectiveness of our exploratory analytics approach in the discovery of useful information from the patent corpus.  相似文献   
993.
In early 1990, motivated largely by concern for the highly structured nature of engineering education, the faculty of Purdue's School of Mechanical Engineering initiated a two-year assessment of its curriculum. A principal conclusion of this assessment was that students should have more exposure to open-ended, cross-functional problems and that design, interpreted broadly, provided the best platform for launching appropriate curriculum changes. Specific plans for curriculum revision included a) early exposure to design and the product realization process, including issues such as marketing, manufacturing and economics, as well as concept generation, evaluation and documentation; b) integration of design and open-ended problem solving experiences across the curriculum, including the core engineering sciences courses; c) development of the softer skills associated with communication and teamwork; and d) greater emphasis on engineering practice through increased linkages with industry. To varying degrees, progress has been made on each of the foregoing objectives, and the purpose of this paper is to describe the nature of the curriculum revisions, as well as the process by which an implementation plan was developed. A retrospective assessment of the revisions and the implementation process is also provided.  相似文献   
994.
Polydimethylsiloxane (PDMS) is a commonly used material in biomedical engineering (Sollier et al. in Lab Chip 11(22):3752–3765, 2011; Palchesko et al. in PLoS ONE 7(12):e51499, 2012; Berthier et al. in Lab Chip 12(7):1224–1237, 2012). Its elastic nature makes PDMS especially attractive for microfluidic large-scale integration (mLSI) technology where micromechanical valves are actuated by deflecting a PDMS membrane under pressure. Therefore, understanding and control of PDMS elastic properties have commercial and scientific significance. In this study, we have investigated the effects of pre-polymer/cross-linker storage conditions on the mechanical properties of cured PDMS films as well as on microfluidic devices. We have showed that when the uncured components of PDMS are exposed to different humidity conditions, the elasticity of the PDMS changes and this is revealed as a change in the Young’s modulus of the cured PDMS. The high humidity (~85%) exposure for 24 h causes PDMS to become softer as confirmed by a significant decrease in the Young’s modulus values from 1.2 to 0.9 MPa. Furthermore, as the PDMS is exposed to high humidity conditions for longer periods (72 h), the Young’s modulus decreases down to 0.7 MPa. We found that exposing only the pre-polymer PDMS (Part A) to humid air does not alter the cured PDMS properties significantly, whereas exposure of the cross-linker (Part B) is responsible for the elasticity change. We have strictly controlled the storage humidity to build more reliable microfluidic chips using mLSI. As a result, actuation pressure of valves (10 psi) and defects of devices (in <30% of chips) are significantly reduced. These results suggest that to improve the manufacturing yield and reliability of PDMS devices, storage humidity should be controlled immediately after the material synthesis.  相似文献   
995.
Four simplifications in the calculation of safety instrumented system logic solver performance measures (mean time to failure and risk reduction factor) clarify the dependence on the various factors involved. These include failure rate, fail safe fraction, diagnostics coverage and common cause. Approximate MTTF and RRF formulas are developed for 1oo2D and TMR logic solvers. These provide an explicit indication of which factors have the greatest influence on improving safety.  相似文献   
996.
Multi-Class Segmentation with Relative Location Prior   总被引:2,自引:0,他引:2  
Multi-class image segmentation has made significant advances in recent years through the combination of local and global features. One important type of global feature is that of inter-class spatial relationships. For example, identifying “tree” pixels indicates that pixels above and to the sides are more likely to be “sky” whereas pixels below are more likely to be “grass.” Incorporating such global information across the entire image and between all classes is a computational challenge as it is image-dependent, and hence, cannot be precomputed. In this work we propose a method for capturing global information from inter-class spatial relationships and encoding it as a local feature. We employ a two-stage classification process to label all image pixels. First, we generate predictions which are used to compute a local relative location feature from learned relative location maps. In the second stage, we combine this with appearance-based features to provide a final segmentation. We compare our results to recent published results on several multi-class image segmentation databases and show that the incorporation of relative location information allows us to significantly outperform the current state-of-the-art.  相似文献   
997.

Objective

To determine prevalence and correlates of handgun access among adolescents seeking care in an urban Emergency Department (ED) in order to inform future injury prevention strategies.

Methods

In this observational cross-sectional study performed in the ED of a large urban hospital, 14- to 18-year-old adolescents completed a computerized survey of risk behaviors. Adolescents seeking ED care (for injury or medical complaint) were approached seven days a week over a 22-month period. Validated measures included measures of demographics, sexual activity, substance use, injury, violent behavior, and handgun access. A logistic regression model predicting handgun access was performed.

Results

A total of 3050 adolescents completed the survey (44% male, 58.9% African-American), with 417 (12%) refusing to participate. One-third of the sample (n = 1003) reported access to a handgun, and of those 54% were males (n = 542). Logistic regression results indicated that older age (AOR: 1.58; 95% CI: 1.30-1.94), African-American race (AOR: 1.34; 95% CI: 1.11-1.61), male gender (AOR: 1.99; 95% CI: 1.66-2.37), and being employed (AOR: 1.35; 95% CI: 1.11-1.65), as well as seeking ED care for a medical complaint as compared to intentional injury (AOR: 1.69; 95% CI 1.62-2.50) predicted handgun access. Binge drinking (AOR: 1.75; 95% CI: 1.37-2.27), marijuana use (AOR: 1.93; 95% CI: 1.58-2.36), sexual activity (AOR: 1.64; 95% CI: 1.32-2.02), prior injury by a gun (AOR: 1.80; 95% CI: 1.32-2.46), serious physical violence (AOR: 1.37; 95% CI: 1.13-1.66) and group fighting (AOR: 2.07; 95% CI: 1.68-2.56) also predicted access.

Conclusions

High rates of handgun access were evident among adolescents presenting in an inner city ED, including those seeking care for non-injury related reasons. Adolescents with access to handguns were more likely to report risk behaviors and past injury, providing clinicians with an opportunity for injury prevention initiatives.  相似文献   
998.
Current real-time volumetric scanners use a 2-D array to scan a pyramidal volume consisting of many sector scans stacked in the elevation direction. This scan format is primarily useful for cardiac imaging to avoid interference from the ribs. However, a real-time rectilinear volumetric scan with a wider field of view close to the transducer could prove more useful for abdominal, breast, or vascular imaging. In previous work, computer simulations of very sparse array transducer designs in a rectilinear volumetric scanner demonstrated that a Mills cross array showed the best overall performance given current system constraints. Consequently, a 94×94 Mills cross array including 372 active channels operating at 5 MHz has been developed on a flexible circuit interconnect. In addition, the beam former delay software and scan converter display software of the Duke volumetric scanner were modified to achieve real-time rectilinear volumetric scanning consisting of a 30-mm×8-mm×60-mm scan at a rate of 47 volumes/s. Real-time rectilinear volumetric images were obtained of tissue-mimicking phantoms, showing a spatial resolution of 1 to 2 mm. Images of carotid arteries in normal subjects demonstrated tissue penetration to 6 cm  相似文献   
999.

Smoke alarms are relied upon to notify building occupants of a fire, and the performance of these devices in the fire environment is critical for the safe evacuation of the building occupants. Development of smoke detection technology has focused primarily on the activation time of the smoke alarm and the amount of escape time they will provide. The growth rate of fires in industrial and residential settings has increased significantly in the past four decades, often attributed to the construction and materials of modern-day furnishings and contents compared to that in the 1970s. This changes the thermal environment smoke alarms are exposed to and raises the question whether they are able to alert the occupants before failing due to heat exposure. Research by Ashley et al. in 2005 showed that approximately 30 s of sounding time is necessary to reliably awaken a sleeping occupant and initiate egress. As research has primarily focused on the activation of smoke alarms, there is a gap in the industry knowledge of the thermally induced failure in these devices. Experiments using two different smoke alarm designs were performed in a heated tunnel with induced airflow. The alarms were heated until they reached a code-mandated audibility failure criterion of less than 5 dB above ambient levels, as well as complete cessation of the audible alarm sound during experimental testing. For these samples, reduction in sound signal started to occur at a component temperature of 56°C, and all alarms had stopped sounding when heated to 144°C. The results of a plunge heating test were used to compute a generalized two-stage Response Time Index for the thermal response of each type of smoke alarm. The output data from the NIST Home Smoke Alarm Tests performed in 2008 were used to calculate the estimated time when the smoke alarm would have thermally failed during those tests. The calculations showed that in the scenarios analyzed, both smoke alarm designs tested would provide more than the 30 s required, before reduced audibility or failure occurs. The failure of both alarm designs in just over 3 min shows that more research is needed applying this methodology to a wider range of alarm models and fire scenarios to ensure that smoke alarms are able to provide adequate protection in modern fires.

  相似文献   
1000.
Hydrology is a primary control on the ecological quality of river systems, through its influence on flow, channel geomorphology, water quality and habitat availability. Scottish rivers are widely perceived to be of high ecological quality, with abundant flow volumes and high water quality. However, historical and current river flow regulations, and land use change have altered the physical and chemical characteristics of Scottish rivers, with adverse consequences for aquatic biota. Baseline hydrological, geomorphological and water quality conditions in Scottish rivers are thus summarised. The impacts of river regulation and land use change on the hydrology, geomorphology and water quality of Scottish rivers are then discussed. Consequences of these changes for aquatic habitat are examined, with particular reference to the economically significant salmonid species (Salmo salar and Salmo trutta). Policy and management issues relating to the future ecological quality of Scottish rivers are reviewed. These include the impacts of climate change on ecological quality, the calculation and implementation of ecologically acceptable flows, and river restoration and best management practices within integrated catchment planning.  相似文献   
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