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81.
Text extraction and document image segmentation using matched wavelets and MRF model. 总被引:1,自引:0,他引:1
Sunil Kumar Rajat Gupta Nitin Khanna Santanu Chaudhury Shiv Dutt Joshi 《IEEE transactions on image processing》2007,16(8):2117-2128
In this paper, we have proposed a novel scheme for the extraction of textual areas of an image using globally matched wavelet filters. A clustering-based technique has been devised for estim ating globally matched wavelet filters using a collection of groundtruth images. We have extended our text extraction scheme for the segmentation of document images into text, background, and picture components (which include graphics and continuous tone images). Multiple, two-class Fisher classifiers have been used for this purpose. We also exploit contextual information by using a Markov random field formulation-based pixel labeling scheme for refinement of the segmentation results. Experimental results have established effectiveness of our approach. 相似文献
82.
83.
Total site integration offers energy conservation opportunities across different individual processes and also to design as well as to optimize the central utility system. In total site integration of the overall process, indirect integration with intermediate fluids or through a central utility system are preferred as it offers greater advantages of flexibility and process control but with reduced energy conservation opportunities. To achieve the maximum possible indirect integration between processes assisted heat transfer, i.e., heat transfer outside the region between process pinch points, plays a significant role. A new concept is proposed in this paper for total site integration by generating a site level grand composite curve (SGCC). Proposed SGCC targets the maximum possible indirect integration as it incorporates assisted heat transfer. In this paper, a methodology is proposed to estimate the cogeneration potential at the total site level, utilizing the concept of multiple utility targeting on the SGCC. The proposed methodology to estimate the cogeneration potential is simple and linear as well as utilizes the rigorous energy balance at each steam header. 相似文献
84.
Pijush Kanti Chattopadhyay Srinivasan Praveen Narayan Chandra Das Santanu Chattopadhyay 《Polymer Engineering and Science》2013,53(5):923-930
Influence of organic modifying agent of clay on dispersion, distribution, hybrid microstructure formation, and associated performance properties of epoxidized natural rubber‐based composites was evaluated. Binary and ternary composites of carbon black (CB) and two organomodified layered silicates (i.e., nanomer I30E and Cloisite 30B) were prepared and characterized based on small angle X‐ray scattering, transmission electron microscopy, hydrodynamic swelling, tensile measurement, and dynamic mechanical analyses. Greater extent of exfoliation and “nanounit” formation was noted in ternary composites containing nanomer I30E, which was reflected in higher interfacial roughness (ds = 2.82) and lower radius of gyration (Rg = 205 Å). Morphological observations suggested higher nanomer I30E–CB interactions than that of Cloisite 30B–CB. The interplatelet distance in Cloisite 30B (d = 1.83 nm) stacks was lower than that of nanomer I30E (d = 2.26 nm). These two factors jointly contributed in higher breakdown of nanomer I30E stacks by CB than that of Cloisite 30B stacks. Greater exfoliation and nanounit formation in I30E–CB‐filled nanocomposite was also reflected in increased degree of crosslinking (n = 20 × 10?5%), tensile modulus/strength, half height width of damping peak (20.3°C), and filler effectiveness (C = 0.33). POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers 相似文献
85.
Santanu Bandyopadhyay Ranjan K. Malik Uday V. Shenoy 《Computers & Chemical Engineering》1998,22(12):4838-1744
The temperature–enthalpy (T–H) diagram of a distillation column at practical near-minimum thermodynamic condition (PNMTC) or the column grand composite curve (CGCC) is a useful representation for energy targeting studies and may be generated from a converged simulation of a base-case column design. The calculation procedure for the CGCC involves determination of the net enthalpy deficit at each stage by generating envelopes from either the condenser end (top-down approach) or the reboiler end (bottom-up approach). However, the values calculated by the two approaches differ for stages with feeds because existing procedures for CGCC generation do not consider the enthalpy balances at the feed stages. In fact, the net enthalpy deficits at feed stages calculated by both approaches are erroneous even for the simplest case of binary distillation. A feed stage correction (FSC) that rigorously considers the mass and enthalpy balance equations at feed stages is proposed in this work to resolve the discrepancy. Instead of assuming that the compositions obtained from the converged simulation for a feed stage will remain unchanged at PNMTC, the pinched compositions for the feed are determined by the intersection of the equilibrium curve and the feed q-line. Rather than perform an additional flash calculation to establish the pinched feed compositions, a quadratic approximation is developed here for column targeting purposes by assuming the relative volatility obtained from the simulation to remain constant in the neighborhood of the feed stage. The proposed FSC ensures that the CGCC is identical whether the calculations are performed by the top-down approach or the bottom-up approach. The effect of the FSC on the targets for energy conservation by reflux modification, feed conditioning, and introduction of side reboilers/condensers is discussed. As the energy target for reflux modification is determined by the CGCC pinch which typically occurs at or close to the feed location, the significance of the FSC on the reflux modification target is highlighted through several case studies including a complex column featuring multiple feeds and consequently multiple pinch points. The CGCCs for these case studies are generated by a computer program based on the FSC and a single analytical equation for the calculation of the net enthalpy deficits that allows every stage to have a feed, liquid product, vapor product, and side exchanger. The studies show that the reflux modification targets may be erroneous in many cases, if the FSC is ignored. 相似文献
86.
Saikat Maitra Farooq Ahmad Ananta K. Das Santanu Das Binay K. Dutta 《Bulletin of Materials Science》2010,33(2):185-190
In the present work the reaction between fly ash and lime in fly ash-lime compacts under water curing and steam curing conditions
was studied thoroughly in relation to the processing conditions. Fly ash from different sources were collected, characterized,
mixed with lime in different ratios and compacted. The compacts were cured with water and steam separately. The reduction
in the free CaO content in these compacts was measured as a function of curing time and curing process. Role of two ionic
additives, FeCl3 and MgCl2, on the reaction between fly ash and lime was also investigated by measuring the free CaO content. Kinetics of these reactions
was studied by determining the reaction order and rate constants with respect to the free CaO content and it was observed
that the curing conditions and additives affected the reaction kinetics significantly. 相似文献
87.
Empirical studies in software engineering can involve a variety of organizations, each with their own set of policies and procedures geared at safeguarding the interests and responsibilities of the researchers, students, the collaborating company, the university, and possibly national funding agencies like the National Science Foundation and the National Institute of Health. Each of these organizations have differing goals for participating in these studies and bring widely different cultures and expectations to the table. While policies, procedures, contracts, and agreements set expectations, they by themselves cannot ensure ethical behavior. This position paper describes some of the common approaches to encourage ethical behavior and their limits for enforcing ethical behavior. 相似文献
88.
In the above-named work (see ibid., vol.38, p.51-7, April 1989), S. Lafiti and A. El-Amawy apply, in a straightforward manner, the method developed by A.D. Singh (1985) to calculate lower bounds for the yield of nonplanar interstitial redundancy topologies of processor arrays with spare processors. In their introduction, they claim that the models suggested by I. Koren and D.K. Pradhan (1987) are highly theoretical since the number of states in the Markov model might be very large and the determination of the transition rates might be intractable. They add that applying some empirical rules, as suggested by Koren and Pradhan (1987), can lead to unrealistic results and may require a large number of computations. They also claim that the model of Koren and Pradhan does not suggest an algorithm to replace faulty elements. They conclude that a simpler model, like the one proposed by Singh, is needed for calculating the yield of fault-tolerant processor arrays. In the present comment, Koren and Pradhan respond to the above comments and attempt to clarify the differences between their yield analysis and that of Singh 相似文献
89.
T. V. Narasaiah R. N. P. Choudhary A. K. Pradhan 《Journal of Materials Science》1987,22(10):3571-3575
The Raman and infrared spectra of polycrystalline samples TlH2AsO4, TlD2AsO4, TlH2PO4 and TlD2PO4 have been investigated at 300 K in the frequency ranges 0 to 4000 and 200 to 4000cm–1 respectively. The assignment of lattice, internal, and OH group vibrations has been approximated in terms of symmetry species. Although all the vibrations follow more or less the space group symmetry, the internal vibrations do not completely fulfill the requirements of the symmetry rule. The isotope effect was observed prominently on both compounds in Raman and infrared spectra. An attempt has been made to assign and explain the results. 相似文献
90.
This study examined the effects of procedural justice on state-dependent self-esteem using the group-value model and attribution theory to present competing theoretical perspectives. The group-value model predicts a positive relationship between self-esteem and fair procedures. In contrast, attribution theory suggests procedural fairness interacts with outcome favorability to influence self-esteem. Thus, fair procedures will result in higher self-esteem ratings than unfair procedures when the outcome is positive but will result in lower self-esteem ratings than unfair procedures when the outcome is negative. The results of a laboratory and field study provide converging evidence to support the attribution theory predictions. The results of a 2nd laboratory study suggest that self-esteem is influenced by outcome expectancies, not actual outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献