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991.
Jackson D. Waingold A. 《IEEE transactions on pattern analysis and machine intelligence》2001,27(2):156-169
A program's object model captures the essence of its design. For some programs, no object model was developed during design; for others, an object model exists but may be out-of-sync with the code. This paper describes a tool that automatically extracts an object model from the class-files of a Java program. Unlike existing tools, it handles container classes by inferring the types of elements stored in a container and eliding the container itself. This feature is crucial for obtaining models that show the structure of the abstract state and bear some relation to conceptual models. Although the tool performs only a simple, heuristic analysis that is almost entirely local, the resulting object model is surprisingly accurate. The paper explains what object models are and why they are useful; describes the analysis, its assumptions, and limitations; evaluates the tool for accuracy, and illustrates its use on a suite of sample programs 相似文献
992.
Fundamental physicochemical data is required for the design and optimization of food engineering processes, such as extraction. Flavonoids are present in natural products such as grapes and have numerous health benefits particularly with respect to their reported antioxidant properties. Such flavonoid compounds can be extracted from these natural products using a variety of solvents, among them water. In this study, the aqueous solubilities of 3,3′,4′,5,7-pentahydroxyflavone (quercetin) and its dihydrate were measured at temperatures between 25 and 140 °C using a continuous flow type apparatus. The flow rate of subcritical water was studied at 0.1, 0.2 and 0.5 mL/min to study its effect on quercetin solubility and thermal degradation at temperatures greater than 100 °C. The aqueous solubility of anhydrous quercetin varied from 0.00215 g/L at 25 °C to 0.665 g/L at 140 °C and that of quercetin dihydrate varied from 0.00263 g/L at 25 °C to 1.49 g/L at 140 °C. The aqueous solubility of quercetin dihydrate was similar to that of anhydrous quercetin until 80 °C. At temperatures above or equal to 100 °C, the aqueous solubility of quercetin dihydrate was 1.5–2.5 times higher than that of anhydrous quercetin. The aqueous solubility of quercetin anhydrate and dihydrate at different temperatures was correlated using a modified Apelblat equation. The thermodynamic properties of the solution of quercetin and its dihydrate in water were than estimated from their solubility values. A flow rate effect on the aqueous solubility of quercetin and its dihydrate was not observed until above 100 °C where higher solvent (water) flow rates (>0.1 mL/min) were required to maintain a constant solubility in the saturation cell and with minimal thermal degradation of the solute (quercetin dihydrate). The study of its particle morphology under SEM indicated an aggregation of the crystals of quercetin dihydrate at subcritical water temperatures and at lower flow rates (<0.5 mL/min), thereby inhibiting stable solubility measurements and solvent flow through the saturation cell. 相似文献
993.
J. S. Jackson 《金属精饰学会汇刊》2013,91(1):89-101
Most steels take up hydrogen very readily and suffer injury to the fracture characteristics, the effects being serious for strong steels. Effects of hydrogen arising from corrosion of the steel are discussed and the very adverse influence of sulphides is indicated. The amounts of hydrogen capable of causing loss of resistance to fracture are very small. Data on the observed amounts are given. Ways in which hydrogen contents can be observed are discussed. Effects of mechanical strain on steels under stress and with access of hydrogen are considered with regard to movement of hydrogen to highly stressed areas. References to published research work are given and some of the views on mechanism of the observed effects are indicated. 相似文献
994.
Jerry Chun-Wei Lin Wensheng Gan Philippe Fournier-Viger Tzung-Pei Hong Han-Chieh Chao 《Knowledge and Information Systems》2017,51(3):873-909
Recently, high utility pattern mining (HUPM) has been extensively studied. Many approaches for HUPM have been proposed in recent years, but most of them aim at mining HUPs without any consideration for their frequency. This has the major drawback that any combination of a low utility item with a very high utility pattern is regarded as a HUP, even if this combination has low affinity and contains items that rarely co-occur. Thus, frequency should be a key criterion to select HUPs. To address this issue, and derive high utility interesting patterns (HUIPs) with strong frequency affinity, the HUIPM algorithm was proposed. However, it recursively constructs a series of conditional trees to produce candidates and then derive the HUIPs. This procedure is time-consuming and may lead to a combinatorial explosion when the minimum utility threshold is set relatively low. In this paper, an efficient algorithm named fast algorithm for mining discriminative high utility patterns (DHUPs) with strong frequency affinity (FDHUP) is proposed to efficiently discover DHUPs by considering both the utility and frequency affinity constraints. Two compact structures named EI-table and FU-tree and three pruning strategies are introduced in the proposed algorithm to reduce the search space, and efficiently and effectively discover DHUPs. An extensive experimental study shows that the proposed FDHUP algorithm considerably outperforms the state-of-the-art HUIPM algorithm in terms of execution time, memory consumption, and scalability. 相似文献
995.
996.
Beach Scott R.; Schulz Richard; Yee Jennifer L.; Jackson Sharon 《Canadian Metallurgical Quarterly》2000,15(2):259
Data from the first 2 waves of the Caregiver Health Effects Study (n? =? 680) were analyzed to examine the effects of changes in caregiving involvement on changes in caregiver health-related outcomes in a population-based sample of elders caring for a disabled spouse. Caregiving involvement was indexed by levels of (a) spouse physical impairment, (b) help provided to the spouse, and (c) strain associated with providing help. Health-related outcomes included perceived health, health-risk behaviors, anxiety symptoms, and depression symptoms. Increases in spouse impairment and caregiver strain were generally related to poorer outcomes over time (poorer perceived health, increased health-risk behaviors, and increased anxiety and depression), whereas increased helping was related to better outcomes (decreased anxiety and depression). Results suggest that caring for a disabled spouse is a complex phenomenon that can have both deleterious and beneficial consequences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Geophysical techniques offer the capability to non-invasively investigate engineering structures, both in terms of their spatial variability, and the prediction of properties of interest to the engineer from the ‘pixel’ values of the geophysical tomograms. The combined use of different geophysical methods provides a means of identifying the signature of salient engineering conditions. The response of seismic, radar and electrical resistivity tomography to simple targets within masonry structures is demonstrated. The benefits of combining rapid standard radar surveys with more detailed tomography is discussed and strategies for investigating typical structures developed. The response of the three methods, acoustic, electrical and radar to changes in the condition of masonry, such as reduction in strength and ingress of water, are discussed, with particular reference to a case study utilising the Ribblehead viaduct as an example. The corresponding responses to changes in ground conditions are also presented and shown to be important in understanding possible further applications of these methods, such as investigating behind retaining walls. 相似文献
998.
Many parts with leading-edge technologies (e.g., microprocessors, low-voltage logic devices, and high-capacity DRAMs) are available mostly in commercial or industrial temperature ranges. Some companies are responding by using the available parts in temperature ranges wider than those for which they are specified (uprating). The use of uprated parts should be considered as an option to mitigate environmental mismatch only when no other feasible alternative can be found. Companies who uprate parts must follow documented, controlled and repeatable processes, and they still may be subject to liability if a product that used uprated parts fails or is suspected to have caused harm. Product liability defenses are available to companies who use electronic parts outside the original manufacturer's specified temperature ranges. In order to maximize the effectiveness of these defenses, however, a company must be vigilant in seeking out ways in which it can demonstrate the viability of these defenses before the lawsuit is ever filed. Both the government contractor defense and the contract specification defense are vehicles around which a company can establish a product liability prevention program. In the final analysis, there is no substitute in product liability prevention for the training and education of employees and the endorsement by senior management of such a program 相似文献
999.
1000.
Security for Grids 总被引:2,自引:0,他引:2
Humphrey M. Thompson M.R. Jackson K.R. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2005,93(3):644-652
Securing a Grid environment presents a distinctive set of challenges. This work groups the activities that need to be secured into four categories: naming and authentication; secure communication; trust, policy, and authorization; and enforcement of access control. It examines the current state of the art in securing these activities and introduces new technologies that promise to meet the security requirements of Grids more completely. 相似文献