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101.
This paper reflects on 20 years of behavioural research in telecommunications published in BIT. The past 20 years have seen major changes in telecommunications technology and applications. They have also seen the deregulation of telecommunications markets and the pervasive penetration of the working environment by networked systems. Papers published in BIT have reflected these changes. Some research topics have attracted continuing interest throughout this period, and two are reviewed briefly: the effect of network delays on users and the relative effectiveness of different media and user choices between them. In addition many new technical and theoretical developments have been reported. Two major theoretical trends have been the convergence between behavioural research in telecommunications and computing, and the rise in social-science-based research. The question whether published behavioural research has been able to influence the development of the technologies studied is considered. Finally, the paper speculates on future topics for research.  相似文献   
102.
Textured silicon wafers used in silicon solar cell manufacturing offer superior light trapping, which is a critical enabler for high-performance photovoltaics. A similar optical benefit can be obtained in monolithic perovskite/silicon tandem solar cells, enhancing the current output of the silicon bottom cell. Yet, such complex silicon surfaces may affect the structural and optoelectronic properties of the overlying perovskite films. Here, through extensive characterization based on optical and microstructural spectroscopy, it is found that the main effect of such substrate morphology lies in an altering of the photoluminescence response of the perovskite, which is associated with thickness variations of the perovskite, rather than lattice strain or compositional changes. With this understanding, the design of high-performance perovskite/silicon tandems is rationalized, yielding certified power conversion efficiencies of >28%.  相似文献   
103.
We propose a new approach to interactive design of metallic and pearlescent coatings, such as automotive paints and plastic finishes of electronic appliances. This approach includes solving the inverse problem, that is, finding pigment composition of a paint from its bidirectional reflectance distribution function (BRDF) based on a simple paint model. The inverse problem is solved by two consecutive optimizations calculated in real-time on a contemporary PC. Such reverse engineering can serve as a starting point for subsequent design of new paints in terms of appearance attributes that are directly connected to the physical parameters of our model. This allows the user to have a paint composition in parallel with the appearance being designed.  相似文献   
104.
The problem of finding a spanning forest of a graph in a distributed-processing environment is studied. If an input graph is weighted, then the goal is to find a minimum-weight spanning forest. The processors communicate by broadcasting. The output consists of the edges that make a spanning forest and have been broadcast on the network. Input edges are distributed among the processors, with each edge held by one processor. The underlying broadcast network is implemented as a multiple-access channel. If exactly one processor attempts to perform a broadcast, then the broadcast is successful. A message broadcast successfully is delivered to all the processors in one step. If more than one processors broadcast simultaneously, then the messages interfere with each other and no processor can receive any of them. Optimality of algorithmic solutions is investigated, by way of comparing deterministic with randomized algorithms, and adaptive with oblivious ones. Lower bounds are proved that either justify the optimality of specific algorithms or show that the optimal performance depends on a class of algorithms.  相似文献   
105.
The impact of new and emerging therapies on the microenvironment of primary cutaneous lymphomas (PCLs) has been recently raised in the literature. Concomitantly, novel treatments are already used or registered (dupilumab, upadacitinib) and others seem to be added to the armamentarium against atopic dermatitis. Our aim was to review the literature on interleukins 4, 13, 22, and 31, and JAK/STAT pathways in PCLs to elucidate the safety of using biologics (dupilumab, tralokinumab, fezakinumab, nemolizumab) and small molecule inhibitors (upadacitinib, baricitinib, abrocitinib, ruxolitinib, tofacitinib) in the treatment of atopic dermatitis. We summarized the current state of knowledge on this topic based on the search of the PubMed database and related references published before 21 October 2021. Our analysis suggests that some of the mentioned agents (dupilumab, ruxolitinib) and others may have a direct impact on the progression of cutaneous lymphomas. This issue requires further study and meticulous monitoring of patients receiving these drugs to ensure their safety, especially in light of the FDA warning on tofacitinib. In conclusion, in the case of the rapid progression of atopic dermatitis/eczema, especially in patients older than 40 years old, there is a necessity to perform a biopsy followed by a very careful pathological examination.  相似文献   
106.
Background: Dissemination of breast cancer (BC) cells through the hematogenous or lymphogenous vessels leads to metastatic disease in one-third of BC patients. Therefore, we investigated the new prognostic features for invasion and metastasis. Methods: We evaluated the expression of miRNAs and epithelial-to-mesenchymal transition (EMT) genes in relation to CDH1/E-cadherin changes in samples from 31 patients with invasive ductal BC including tumor centrum (TU-C), tumor invasive front (TU-IF), lymph node metastasis (LNM), and CD45-depleted blood (CD45-DB). Expression of miRNA and mRNA was quantified by RT-PCR arrays and associations with clinico-pathological characteristics were statistically evaluated by univariate and multivariate analysis. Results: We did not verify CDH1 regulating associations previously described in cell lines. However, we did detect extremely high ZEB1 expression in LNMs from patients with distant metastasis, but without regulation by miR-205-5p. Considering the ZEB1 functions, this overexpression indicates enhancement of metastatic potential of lymphogenously disseminated BC cells. In CD45-DB samples, downregulated miR-205-5p was found in those expressing epithelial and/or mesenchymal markers (CTC+) that could contribute to insusceptibility and survival of hematogenously disseminated BC cells mediated by increased expression of several targets including ZEB1. Conclusions: miR-205-5p and potentially ZEB1 gene are promising candidates for markers of metastatic potential in ductal BC.  相似文献   
107.
The standard site method was used to measure antenna factor. Based on calculation of antenna factor uncertainty, ways of more precise estimation of uncertainty, leading to uncertainty reduction, are presented. Using uncertainty standards together with known approaches to radiated emission measurement uncertainty calculation, a model of antenna factor measurement and an equation for calculation of its uncertainty were derived. Possible steps to reduce resultant measurement uncertainty are described, including an analysis of correlation, and acknowledgment of frequency dependence. The uncertainty was calculated in 25 frequency points in the range from 30 MHz to 1000 MHz. Furthermore, various calculations of uncertainty are executed to examine the suggested effects on the uncertainty value.  相似文献   
108.
Comments on A. Sugarman and A. Wilson, J. F. Murray, F. Busch, Sugarman, J. L. Bachant et al, and Wilson (see PA, Vol 82:33123; 33115; 34118; 33122; 33102; and 33124, respectively), authors of the special section on contemporary structural and relational analysis, and finds little constructive dialog. Marshall states that these articles are characterized by overbroad generalizations, preemptive judgments, and premature conclusions. Marshall also states that many of the articles put relational ideas through the filter of structural psychoanalysis, in the process changing them beyond recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
The main goal of this paper is to present results of comparison study for the level set and direct Lagrangian methods for computing evolution of the Willmore flow of embedded planar curves. To perform such a study we construct new numerical approximation schemes for both Lagrangian as well as level set methods based on semi-implicit in time and finite/complementary volume in space discretizations. The Lagrangian scheme is stabilized in tangential direction by the asymptotically uniform grid point redistribution. Both methods are experimentally second order accurate. Moreover, we show precise coincidence of both approaches in case of various elastic curve evolutions provided that solving the linear systems in semi-implicit level set method is done in a precise way, redistancing is performed occasionally and the influence of boundary conditions on the level set function is eliminated. The authors were partly supported by the following projects and grants: the project HPC-EUROPA(RII3-CT-2003-506079), the NCMM project LC06052, VEGA 1/3321/06 grant, the project MSM 6840770010 and APVV-0247-06, APVV-RPEU-0004-06 grants.  相似文献   
110.
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