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61.
Currently, the manufacturing domain is primarily characterized by the flexibility, adaptability and robustness of the production system. The manufacturing flow processes lead to shorter cycle times to efficiently meet customer needs. Mentioned features can be more easily achieved in a distributed system, such as holonic or multi-agent system, which becomes strongly influenced by the advancement of semantic technologies. In the majority of existing multi-agent based control systems, which are responsible for acting, sensing, computing and production planning, the ontology (necessary for knowledge bases and communication) is usually hard-coded directly in the agent code. In this case, the hard-coded system behavior can be hardly maintained??usually system reprogramming is needed from time to time to satisfy customer requirements. In this paper we discuss the necessity of explicit definition of both declarative and procedural knowledge and propose explicit procedural knowledge handling. Sharing and distribution of such knowledge is discussed and illustrated on an implemented transportation system example. We also introduce the utilization of discussed architecture for explicit specification of agent behavior in failures patterns handling and smart grid configuration scenario. Such a solution greatly increases the possibility of system integration, openness, flexibility, and extensibility, all without having to restart the running distributed system. The topic discussed in this paper shows the ability of the dynamic reconfigurable multi-agent system to participate in development of industrial control systems and solutions.  相似文献   
62.
Abstract

We analyse the dynamics of the q-deformed quantum harmonic oscillator initially prepared in the q-analogue of the coherent state. Non-trivial behaviour of the mean values of the q-position operator is observed. The squeezing of the second-order moments of this operator is studied.  相似文献   
63.
A novel approach to local anodic oxidation technique, which leads to approximately equal 50 nm wide line patterns, is described. The technique is utilized to prepare quantum point contact on a low-mobility semiconductor heterostructure. Transport measurements show quantized conductance in zero magnetic field at 4.2 K thanks to very short one-dimensional constriction. The technique is also used for the definition of low-to-room temperature sub-micrometer Hall probes to show its applicability for the room temperature applications. The magnetic-field resolution and the sensitivity of the probes are evaluated in dependence of the probe dimensions, bias current, and temperature. The 200-nm probe shows magnetic-field resolution of 47 microT/(Hz)(1/2) at 140 Hz and at 4.2 K, when it is driven by 5 microA bias current. The novel approach is promising for the development of the future nano-devices operated both at low and room temperatures. To our knowledge, local anodic oxidation technique applied directly to shallow semiconductor heterostructure has been successfully used for the room temperature application for the first time.  相似文献   
64.
Hason S  Vetterl V 《Analytical chemistry》2006,78(14):5179-5183
We present a simple, cost-effective design for amplifying oligodeoxynucleotide (ODN) sensing, in microliter ODN volumes containing copper ions, by solution streaming (bubbling). The inert gas streaming (bubbling) at a constant pressure of 0.04 bar drives the motion of a 30-microL ODN droplet containing a three-electrode circuit (inverted drop microcell), and in the presence of copper ions offers an approximately 50-times improvement in the detection of ODN samples. The detection of ODNs at the carbon paste electrode is based on the enhancement of the oxidation peaks of purine bases (adenine and guanine) by the anodic stripping of the electrochemically accumulated complex of Cu(I) with purine base residues of acid hydrolyzed ODN samples (Cu(I)-ahODN complex). We used the proposed method for (i) the determination of the percentage content of adenine and guanine units within analyzed ODN samples at subnanomolar concentrations (related to monomer content) and (ii) the detection of the (TTC)n triplet expansion using magnetic DNA hybridization with reporter probes containing guanine units (the TTC trinucleotide repeat expansion is associated with serious hereditary diseases, including Friedreich ataxia).  相似文献   
65.
β-Stabilized titanium (Ti) alloys containing non-toxic elements, particularly niobium (Nb), are promising materials for the construction of bone implants. Their biocompatibility can be further increased by oxidation of their surface. Therefore, in this study, the adhesion, growth and viability of human osteoblast-like MG 63 cells in cultures on oxidized surfaces of a β-TiNb alloy were investigated and compared with the cell behavior on thermally oxidized Ti, i.e. a metal commonly used for constructing bone implants. Four experimental groups of samples were prepared: Ti or TiNb samples annealed to 600 °C for 60 min in a stream of dry air, and Ti and TiNb samples treated in Piranha solution prior to annealing. We found that on all TiNb-based samples, the cell population densities on days 1, 3 and 7 after seeding were higher than on the corresponding Ti-based samples. As revealed by XPS and Raman spectroscopy, and also by isoelectric point measurements, these results can be attributed to the presence of T-Nb2O5 oxide phase in the surface of the alloy sample, which decreased its negative zeta (ζ)-potential in comparison with zeta (ζ)-potential of the Ti sample at physiological pH. This effect was tentatively explained by the presence of positively charged defects acting as Lewis sites of the surface Nb2O5 phase. Piranha treatment slightly decreases the biocompatibility of the samples, which for the alloy samples may be explained by a decrease in the number of defective sites with this treatment. Thus, the presence of Nb and thermal oxidation of β-stabilized Ti alloys play a significant role in the increased biocompatibility of TiNb alloys.  相似文献   
66.
67.
The paper refers to methods used for identification of linear and nonlinear systems. Deterministic and stochastic approaches are distinguished and specific features concerning parameters, structure and state estimation are briefly discussed from the point of view of possible advantages and difficulties for identification. Attention is paid to different final goals of identification with respect to the convenience of the methods in question. The most important trends in identification approaches are argued by unsolved problems of identification, by the complexity of numerical calculations and of practical applications. The significance of the uncertainty in structure, parameters or noise and the possible application of the a priori knowledge of the analysed system are taken into consideration.  相似文献   
68.
69.
The initial stage of free sintering of thoria (ThO2) has been investigated by means of emanation thermal analysis. Thoria powder (having surface area of 18 m2 g–1) was prepared from thorium oxalate (homogeneously labelled by228Th) by heating to 500 ° C. The release of220Rn was studied at various temperatures. The curves of radon diffusion release measured during isothermal heating of thoria powder at four temperatures (705, 735, 780 and 825 ° C) have been used for investigating the kinetics of the surface changes of thoria powder during the initial stage of sintering. The experimental data evaluated obey the kinetic law E p S eff = const ×t n , whereE p is the emanating power due to the diffusion of radon in intergranular space and open pores,S eff is the effective surface area,t is time andn equals 0.64. The effective surface areaS eff has been proposed as a new parameter characterizing the active surface of powdered solid and its changes during sintering.  相似文献   
70.
The paper presents a successful implementation of a flowsheeting package with many features of third generation simulators on a handy and cheap desk-top computer. This version is still powerful enough to solve industrial problems of reasonable size and it is especially suitable for operative calculation in places where it is difficult and/or expensive to reach a terminal network, i.e. branch offices or plants sites.  相似文献   
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