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91.
The focus of the current research was to develop real-time PCR assays with improved sensitivity and the capacity to simultaneously speciate the 3 most common mycoplasma mastitis agents: Mycoplasma bovis, Mycoplasma californicum, and Mycoplasma bovigenitalium. Real-time PCR was chosen because it provides rapid results. Partial 16S rRNA gene sequencing was used as the gold standard for evaluating candidate real-time PCR assays. To ascertain the real-time PCR assay specificity, reference strains of Mycoplasma species, Acholeplasma axanthum, and common gram-positive and gram-negative mastitis pathogens were tested. No cross-reactions were observed. Mycoplasma spp. isolated from bovine milk samples (n=228) and other organ sites (n=40) were tested by the real-time PCR assays and the partial 16S rRNA gene sequencing assay. Overall accuracy of this novel real-time PCR was 98.51%; 4 of 228 isolates identified as M. bovis by the partial 16S rRNA gene sequencing assay were identified as both M. bovis and M. californicum by real-time PCR. Subsequent amplicon sequencing suggested the presence of both M. bovis and M. californicum in these 4 samples. Using a cycle threshold of 37, the detection limits for real-time PCR were 10 copies of DNA template for both M. bovis and M. bovigenitalium, and 1 copy for M. californicum. This real-time PCR assay is a diagnostic technique that may be used as a screening tool or as a confirmation test for mycoplasma mastitis.  相似文献   
92.
This study was designed to evaluate the acoustic parameters of sleeping oronasal respiration as determined by the SNAP system, to identify those that might aid in identifying appropriate candidates for uvulopalatoplasty (UPP). Eighteen UPP patients who completed preoperative and postoperative SNAP testing and assessment interviews were analyzed. Significant multiparametric changes subsequent to UPP were identified. These parameters were then correlated with subjective outcomes and predictive parameters were defined that may aid in the identification of patients who would be the most appropriate candidates for UPP. Predictive correlation with relief of snoring was noted when the relative loudness of velum-like snoring was greater than 12 dB and the snoring distribution was dominated by low-frequency (velum-like) snoring (> 85%). Objective and more accurate UPP candidate selection may be possible using SNAP testing.  相似文献   
93.
A new method for the evaluation of the center-of-mass to laboratory co-ordinates system transformation matrix is developed, by which each element of the matrix is represented as a finite sum of terms depending on the mass number of the scattering nucleus. At present, the elastic transformation matrices given in the ENDF/B files are evaluated by the Amster method, by which each element of the transformation matrix is represented as an infinite sum of terms. A comparison is made between the values of the elements of the elastic transformation matrix of 6Li obtained by the new method and those given in the ENDF/B-V file, and some discrepancies are revealed.  相似文献   
94.
e-Business process interleaving: Managerial and technological implications*   总被引:1,自引:0,他引:1  
The emergence of Internet as the hub of e-business has made business process integration another important frontier of information management and technology. As a result, the management of inter-organizational business processes is now a major concern of corporate managers. We envision that the new and complex ways of interactions among business partners in a supply web will need to be managed effectively as the next generation of the Internet makes cross company workflow a reality. Consequently, business managers are confronted with new issues and new decisions in the strategic and operational aspects of process integration. To facilitate the understanding of these issues, we introduce a new paradigm of business computing referred to as E-business Process Interleaving, which emphasizes the complex and dynamic integration of e-business processes across company boundaries. In this paper, we outline various impacts of this new phenomenon on information management and technology and investigate the enabling technologies of e-business process interleaving. We believe that our work can help the development of the next generation of corporate information infrastructure that enables greater degree of e-business process integration.This research was partly supported by CITM grants including the DoD contract (2000–2001), N00244-00-C0108, and by the State of California NGI Program.  相似文献   
95.
Preface     

Preface

Preface  相似文献   
96.
Consistency of pupils' attributions regarding success and failure.   总被引:1,自引:0,他引:1  
191 6th graders attending schools in 3 socioeconomic areas were asked to attribute to causes their success or failure on examinations administered in 3 subjects in the course of a trimester. The extent of consistency was measured between attributional patterns obtained from 2 tests in the same subject and between two tests in different subjects. Results show consistency in Ss' attributional patterns. It was found that consistency of attributional patterns was significantly greater when Ss received the same outcomes on the 2 tests (success or failure) than when different outcomes were received (success–failure or failure–success). (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
Algorithms for solving partial differential equations which extend previous applications of the nonconforming Taylor discretization method (NTDM) are presented. In one modification the number of interrelated grid points is variable, thus enabling additional geometric flexibility. Another modification is the approximation of the governing differential equation using the method of weighted residuals. A simple one-dimensional test case with a known analytic solution is solved using this code. The results demonstrate that precision is enhanced when using the method of weighted residuals with an increased number of interrelated points. The algorithm is applied as a general purpose two-dimensional code for nonlinear steady state heat-conduction. Two-dimensional examples with complex geometry and boundary conditions are then solved both by the NTDM and by the finite elements method (FEM). The results obtained by the two methods are compared.  相似文献   
98.
Among the common features of advanced LWR concepts are the tightness of lattices and the symbiotic setting of different fuels. Such symbioses often come in the form of multilattices, whose numerically-repeated unit is a configuration of several pins, typically with one pin type at the center and pins of a second type surrounding the center pin. If this extended-cell (EC) unit is cylindricized, then a simple transport calculation of the unit will be possible. If the lattice of such units is tight, there is further an a priori reason to expect the cylindrization to introduce only a small distortion of the true neutron fluxes in the lattice. A strict numerical validation of the EC cylindrization approximation is impractical, but similar validations can be carried out for regular lattices, viewed as being made up of multicell units whose centers are moderators and whose peripheries are fuel pins. In these comparisons the EC cylindrization approximation gives good results.  相似文献   
99.
Cultured in vitro neuronal networks are known to exhibit synchronized bursting events (SBE), during which most of the neurons in the system spike within a time window of approximately 100 msec. Such phenomena can be obtained in model networks based on Markram-Tsodyks frequency-dependent synapses. In order to account correctly for the detailed behavior of SBEs, several modifications have to be implemented in such models. Random input currents have to be introduced to account for the rising profile of SBEs. Dynamic thresholds and inhomogeneity in the distribution of neuronal resistances enable us to describe the profile of activity within the SBE and the heavy-tailed distributions of interspike intervals and interevent intervals. Thus, we can account for the interesting appearance of Levy distributions in the data.  相似文献   
100.
Bellare, Boldyreva, and O’Neill (CRYPTO ’07) initiated the study of deterministic public-key encryption as an alternative in scenarios where randomized encryption has inherent drawbacks. The resulting line of research has so far guaranteed security only for adversarially chosen-plaintext distributions that are independent of the public key used by the scheme. In most scenarios, however, it is typically not realistic to assume that adversaries do not take the public key into account when attacking a scheme. We show that it is possible to guarantee meaningful security even for plaintext distributions that depend on the public key. We extend the previously proposed notions of security, allowing adversaries to adaptively choose plaintext distributions after seeing the public key, in an interactive manner. The only restrictions we make are that: (1) plaintext distributions are unpredictable (as is essential in deterministic public-key encryption), and (2) the number of plaintext distributions from which each adversary is allowed to adaptively choose is upper bounded by \(2^{p}\), where p can be any predetermined polynomial in the security parameter and plaintext length. For example, with \(p = 0\) we capture plaintext distributions that are independent of the public key, and with \(p = O(s \log s)\) we capture, in particular, all plaintext distributions that are samplable by circuits of size s. Within our framework we present both constructions in the random oracle model based on any public-key encryption scheme, and constructions in the standard model based on lossy trapdoor functions (thus, based on a variety of number-theoretic assumptions). Previously known constructions heavily relied on the independence between the plaintext distributions and the public key for the purposes of randomness extraction. In our setting, however, randomness extraction becomes significantly more challenging once the plaintext distributions and the public key are no longer independent. Our approach is inspired by research on randomness extraction from seed-dependent distributions. Underlying our approach is a new generalization of a method for such randomness extraction, originally introduced by Trevisan and Vadhan (FOCS ’00) and Dodis (Ph.D. Thesis, MIT, ’00).  相似文献   
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