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51.
In this paper, we present a mathematical background for a new approach for performances modeling of interconnection networks, based on analyzing the packet blocking and waiting time spent in each channel passing through all possible paths in the channel dependency graph. We have proposed a new, simple and very accurate analytical model for deterministic routing in wormhole networks, which is general in terms of the network topology and traffic distribution. An accurate calculation of the variance of the service time has been developed, which overcomes the rough approximation used, as a rule, in the existing models. The model supports two-dimensional mesh topologies, widely used in network-on-chip architectures, and multidimensional topologies, popular in multicomputer architectures. It is applicable even for irregular topologies and arbitrary application-specific traffic. Results obtained through simulation show that the model achieves a high degree of accuracy.  相似文献   
52.
The drying of microcapsules causes agglomeration and oversized agglomerates disturb fiber melt spinning. In this study, three parameters in co-current spray drying were studied and their influence on agglomeration was established with a morphological analysis, granulometric analysis, differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). The results showed that the inlet temperature, feed rate, and dry matter content have a significant influence on agglomeration; thus, their optimal combination was determined. In these conditions, the microcapsules were dried and applied in fibers.  相似文献   
53.
The intermetallic compound Hf2Ni was the subject of investigations by several methods. The relative stability was checked by calculating its enthalpy and cohesive properties, using the augmented plane wave plus local orbitals (APW + lo) method of ab initio calculations. The kinetics of hydrogen absorption in this compound was investigated in the temperature range from 573 to 823 K, under the constant hydrogen pressure of 1 bar. The obtained rate constants, k (s?1), and hydriding capacities (H/M) are as follows: 0.00038 (0.69), 0.00131 (0.95), 0.00246 (1.13) and 0.0042 (0.92) for temperatures 573, 673, 723 and 823 K, respectively. The changes in crystal structure and morphology caused by multiple hydriding/dehydriding cycles were followed by XRD and SEM.  相似文献   
54.
This paper describes a new numerical procedure for analysing earthing grids buried in horizontally stratified multilayer earth. The procedure is very efficient and general. The total number of layers and the total number of metallically disconnected earthing grids are completely arbitrary. A single earthing grid can be positioned in several layers. The procedure is based on an integral equation formulation. Earthing grid conductors are subdivided into segments and the average potential method is used. Efficiency and generality of the computation procedure are based on the successful application of numerical approximations of two kernel functions of the integral expression for the potential distribution within a single layer which is caused by a point current source. Each kernel function of the observed layer is approximated using a linear combination of 15 exponential functions. Extension from the point source to a segment of the earthing grid conductor is done by integrating the potential contribution due to a line of point current sources along the segment axis. This computational procedure gives highly accurate results in a short execution time. © 1998 John Wiley & Sons, Ltd.  相似文献   
55.
The phase evolution, microstructure, and electrical properties of WO3‐doped ZnO–Bi2O3‐based varistors were investigated for different amounts x (0 ≤  1.60 mol%) of the dopant. When x was less than 0.40, the dissolved W6+ in the β‐Bi2O3 acted as a donor in the grain boundaries and reduced the electrical properties of the ZnO varistors. However, when x was 0.40 mol%, which meant an amount of WO3 equal to that of Bi2O3, the electrical properties dramatically increased, which means the W6+ donor effect is removed at the grain boundaries because a new Bi2WO6 phase was formed in the grain‐boundary regions. The Bi2WO6 phase has high oxygen conductivity at high temperatures; it transfers more oxygen to the grain boundaries in order to further enhance the electrical properties. For x values higher than 0.40 (i.e., an addition of WO3 that is greater than the content of Bi2O3), the electrical properties were steadily reduced in comparison to the composition with = 0.40. This could be explained by the reduced amount of Co, Mn, and Al at the grain boundaries and in the ZnO grains as a result of their incorporation into the ZnWO4 phase. The electrical properties of the ZnO grains and the grain boundaries were in agreement with the results of the impedance spectroscopy analysis.  相似文献   
56.
In this work, we investigated the influence of Al doping on the structure of the (ZnO)5In2O3 homologous phase and the thermoelectric characteristics of (ZnO)5(In1?xAlx)2O3 ceramics for x=0, 0.01, 0.03, 0.05, 0.1, and 0.2, prepared using a classic ceramic procedure and sintering at 1500°C for 2 hours. The Al substituted for In on both the primary sites in the Zn5(In1?xAlx)2O8 homologous phase, the octahedral sites in the basal‐plane inversion boundaries and the trigonal bi‐pyramidal sites in the zig‐zag inversion boundaries, which resulted in a uniformly increased shrinkage of the unit cell with the additions of Al. The a and c parameters were reduced for x=0.2 by a maximum 0.8%. All the samples had similar microstructures, so the differences in the TE characteristics mainly resulted from the effects of the substitution of Al for In, decreasing the charge‐carrier concentration and affecting their mobility. Slightly improved TE characteristics were only observed for Al additions with x=0.01‐0.05, while larger additions of Al only resulted in a reduced electrical conductivity and decreased ZT values in comparison to the un‐doped composition.  相似文献   
57.
Applied Intelligence - The selection of transshipment and handling machinery in container terminals is a complex and responsible task due to a number of daily operations required. Accordingly,...  相似文献   
58.
This study determines the effectiveness of business objectives and key performance indicators (KPIs) of the identified business objectives for different types of enterprise. The evaluations of the relative importance of KPIs are called a fuzzy group‐decision‐making problem. The KPI weights are determined using the fuzzy analytic hierarchical process. The effectiveness of business objectives and KPIs is determined using the adopted Balanced Scorecard Designer Pro. Determination of the KPI rank with respect to each enterprise type is on the basis of Pareto analysis. The priority of management initiatives of the improvement strategy corresponds to the calculated rank, and it has a critical effect on the competitive advantage of any enterprise. The results discuss manufacturing, public and service enterprises, which exist in central Serbia. The proposed approach can also be adapted to different businesses.  相似文献   
59.
The European Commission has adopted Directive 2004/8/EC on the promotion of cogeneration, which the EU Member States, as well as candidates including Croatia, were obliged to accept. Among other terms and conditions, the Directive requires certain support mechanisms, such as feed-in tariff prices and premiums added to market electricity prices. In this paper, the cost effectiveness of selling electricity at the feed-in tariff prices in the selected EU Member States is compared to selling it on the European electricity market, with or without premiums. The results of this comparison will indicate whether correction of the Croatian feed-in tariff price to a higher value would be justified. The cost effectiveness ratio of a cogeneration unit upgraded with mean reverting and jump diffusion processes is used for comparison. At the end of this paper, a method is suggested for the correction of feed-in tariff prices, with examples of corrected prices for the years 2008 and 2009. Such corrections have been proven to be justified and are compared to the feed-in tariff prices in most of the selected EU Member States.  相似文献   
60.
Strokes within pediatric populations are considered to be the 10th leading cause of death in the United States of America, with over half of such events occurring in children younger than one year of life. The multifactorial etiopathology that has an influence on stroke development and occurrence signify the importance of the timely recognition of both modifiable and non-modifiable factors for adequate diagnostic and treatment approaches. The early recognition of a stroke and stroke risk in children has the potential to advance the application of neuroprotective, thrombolytic, and antithrombotic interventions and rehabilitation strategies to the earliest possible timepoints after the onset of a stroke, improving the outcomes and quality of life for affected children and their families. The recent development of molecular genetic methods has greatly facilitated the analysis and diagnosis of single-gene disorders. In this review, the most significant single gene disorders associated with pediatric stroke are presented, along with specific therapeutic options whenever they exist. Besides monogenic disorders that may present with stroke as a first symptom, genetic polymorphisms may contribute to the risk of pediatric and perinatal stroke. The most frequently studied genetic risk factors are several common polymorphisms in genes associated with thrombophilia; these genes code for proteins that are part of the coagulation cascade, fibrolysis, homocystein metabolism, lipid metabolism, or platelets. Single polymorphism frequencies may not be sufficient to completely explain the stroke causality and an analysis of several genotype combinations is a more promising approach. The recent steps forward in our understanding of the disorders underlying strokes has given us a next generation of therapeutics and therapeutic targets by which to improve stroke survival, protect or rebuild neuronal connections in the brain, and enhance neural function. Advances in DNA sequencing and the development of new tools to correct human gene mutations have brought genetic analysis and gene therapy into the focus of investigations for new therapeutic options for stroke patients.  相似文献   
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