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51.
In today's competitive business environment, it is important that customers are able to obtain their preferred items in the shops they visit, particularly for convenience store chains such as 7–Eleven where popular items are expected to be readily available on the shelves of the stores for buyers. To minimize the cost of running such store chains, it is essential that stocks be kept to a minimum and at the same time large varieties of popular items are available for customers. In this respect, the replenishment system needs to be able to cope with the taxing demands of minimal inventory but at the same time keeping large varieties of needed items. This paper proposes a replenishment system which is able to respond to the fluctuating demands of customers and provide a timely supply of needed items in a cost–effective way. The proposed system embraces the principle of fuzzy logic which is able to deal with uncertainties by virtue of its fuzzy rules reasoning mechanism, thereby leveraging the responsiveness of the entire replenishment system for the chain stores. To validate the feasibility of the approach, a case study has been conducted in an emulated environment with promising results.  相似文献   
52.
Ant routing is a method for network routing in agent technology. Although its effectiveness and efficiency have been demonstrated and reported in the literature, its properties have not yet been well studied. This paper presents some preliminary analysis on an ant algorithm in regard to its population growing property and jumping behavior. Results conclude that as long as the value max, {i/spl Omega//sub j/|} is known, the practitioner is able to design the algorithm parameters, such as the number of agents being created for each request, k, and the maximum allowable number of jumps of an agent, in order to meet the network constraint.  相似文献   
53.
On agent-mediated electronic commerce   总被引:4,自引:0,他引:4  
This paper surveys and analyzes the state of the art of agent-mediated electronic commerce (e-commerce), concentrating particularly on the business-to-consumer (B2C) and business-to-business (B2B) aspects. From the consumer buying behavior perspective, agents are being used in the following activities: need identification, product brokering, buyer coalition formation, merchant brokering, and negotiation. The roles of agents in B2B e-commerce are discussed through the business-to-business transaction model that identifies agents as being employed in partnership formation, brokering, and negotiation. Having identified the roles for agents in B2C and B2B e-commerce, some of the key underpinning technologies of this vision are highlighted. Finally, we conclude by discussing the future directions and potential impediments to the wide-scale adoption of agent-mediated e-commerce.  相似文献   
54.
The optimization problem corresponding to the design of a presteered broadband processor with maximally flat second-order spatial response in the look direction is discussed. The constraints corresponding to necessary and sufficient conditions for second-order flatness are presented. The nonlinearly constrained optimization approach is unable to consistently locate the global minimum. An approach to solving this problem that essentially converts the nonconvex optimization problem into a parameterized set of convex problems is presented. In the case of 2-D scenarios, the global optimum is determined by finding the roots of a cubic function. The characteristics of the constraints, including the minimum number required and the dependence on the choice of coordinate systems, are examined  相似文献   
55.
56.
To evaluate the diagnostic validity of new assays for bone-specific alkaline phosphatase (BAP), we compared measurements of total alkaline phosphatase (TAP) in serum with results for three different assays of serum BAP in healthy adults (n = 119), patients with chronic nonskeletal disorders (n = 123), and patients with metabolic bone diseases (n = 113). Serum TAP was determined by a standard colorimetric assay, BAP by the methods of lectin precipitation (L-BAP), enzyme immunoassay (E-BAP), and immunoradiometric assay (I-BAP). Impairment of liver function resulted in significant increases of all alkaline phosphatase (AP) measurements, with the smallest changes being exhibited by E-BAP. Compared with the results by TAP, diagnostic sensitivity (i.e., of values exceeding the reference interval) was not improved by BAP, but receiver-operating characteristic (ROC) curve analyses revealed improved discrimination for primary hyperparathyroidism by E-BAP. These results indicate that, in the presence of liver disease, the specificity of AP measurements is improved by measuring BAP. In most other clinical situations, serum TAP appears to provide sufficient clinical information; however, the cross-sectional study design used here allows no statement about the usefulness of BAP in serial measurements.  相似文献   
57.
58.
Ng  H.C. Leung  S.H. Tsang  C.W. 《Electronics letters》1998,34(10):961-963
A new form of line spectral frequency (LSF), bounded line spectral frequency, is presented. It is shown that the new representation is more efficient than the direct line spectral frequency and the differential line spectral frequency (DLSF). By using a vector measure, the scalar quantisation of tenth-order linear predictive coding (LPC) parameters can be coded at 28 bit/frame with a transparent quantisation quality  相似文献   
59.
An experiment was conducted to investigate the effects of immune responsiveness on excretion of oocysts after E. acervulina infection and subsequent effects on production characteristics of broilers (Gallus domesticus). These effects were determined in broilers repeatedly infected with 2.85 x 10(3) oocysts of E. acervulina and treated with various dosages of corticosterone in the diet (0, 10, 20 and 30 p.p.m.). Corticosterone treatment did not have an effect on the peak oocyst excretion, although it was administered from 4 days before initial infection. The number of oocysts excreted shortly after the peak and the length of the excretion period were increased in corticosterone-treated groups. The absence of a difference in peak oocyst excretion was ascribed to the existence of a time-lag between first contact with the parasite and rate of development of protective immunity. In a recently developed computer simulation model this period was assumed to be 5 days. Assuming that immunosuppression, through corticosterone, is only effective when protective immunity is in operation, the results indicate a time-lag of at least a few days, which supports the inclusion of such a time-lag in the computer simulation model. General immunosuppressive effects of the corticosterone treatment, monitored by antibodies and mitogen-induced lymphocyte stimulation confirmed that immunosuppression occurred shortly after medication started. Infection did not have a significant influence on production characteristics in animals without dietary corticosterone. However, with increasing corticosterone levels the negative effects of infection on production also increased.  相似文献   
60.
Extracellular amyloid beta-peptide (A beta) deposition is a pathological feature of Alzheimer's disease and the aging brain. Intracellular A beta accumulation is observed in the human muscle disease, inclusion body myositis. A beta has been reported to be toxic to neurons through disruption of normal calcium homeostasis. The pathogenic role of A beta in inclusion body myositis is not as clear. Elevation of intracellular calcium following application of calcium ionophore increases the generation of A beta from its precursor protein (betaAPP). A receptor-based mechanism for the increase in A beta production has not been reported to our knowledge. Here, we use caffeine to stimulate ryanodine receptor (RYR)-regulated intracellular calcium release channels and show that internal calcium stores also participate in the genesis of A beta. In cultured HEK293 cells transfected with betaAPP cDNA, caffeine (5-10 mM) significantly increased the release of A beta fourfold compared with control. These actions of caffeine were saturable, modulated by ryanodine, and inhibited by the RYR antagonists ruthenium red and procaine. The calcium reuptake inhibitors thapsigargin and cyclopiazonic acid potentiated caffeine-stimulated A beta release. NH4Cl and monensin, agents that alter acidic gradients in intracellular vesicles, abolished both the caffeine and ionophore effects. Immunocytochemical studies showed some correspondence between the distribution patterns of RYR and cellular betaAPP immunoreactivities. The relevance of these findings to Alzheimer's disease and inclusion body myositis is discussed.  相似文献   
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