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1.
This report concerns an ambitious project which created a functionally independent team of young people with physical disabilities who had no previous experience of employment. The aim of the project was to expand the training opportunities for people with disabilities through the provision of team-building. The team was brought together in order to run a self-financing office bureau business in Athens, providing services to the local community. This project intended to find an innovative alternative to sheltered workshops, which are not found in Greece. A systemic and developmental approach to team-building was explored. The approach consisted of work-hardening, education, experiential learning, and providing the physical structures necessary for self-employment. The paper describes the approach with examples, and includes an evaluation by the trainees. The paper also identifies the importance of including a team-building approach within vocational rehabilitation.  相似文献   
2.
Relatively uniform polymeric microspheres, the coefficients of variation being close to 10%, were obtained by the BPO-initiated suspension polymerization of styrenic monomers. Unlike the conventional stirred-tank system, a particular microporous glass membrane (SPG) provided uniform monomer droplets continuously when monomer was allowed to permeate through the micropores. The monomer droplets were suspended in an aqueous solution containing the stabilizing agents, transferred to a stirred vessel, and polymerized. Up to 10μm spheres, of a far narrower size distribution than those obtained by conventional microsuspension polymerization spheres, were obtained. The initial droplet size and distribution were retained with the successful suppression of secondary particle nucleation by the addition of hydroquinone in the aueous phase. Crosslinked polystyrene spheres were also synthesized in the presence of various low-molecular-weight diluents. While a good solvent, toluene, was not so effective; poor solvents, n-heptane and n-heptane, easily yielded the microporous structure, the specific surface area being as high as 160 m2/g. © 1994 John Wiley & Sons, Inc.  相似文献   
3.
采用电子衍射方法对Fe-1.83C马氏体室温时效时产生的有序相结构进行研究,确定其结构为偏离化学计量成分Fe_4C的γ′-Fe_4结构,称为γ′-Fe_xC(Ⅰ)(x=4-11)。碳原子位于单胞的1/2,1/2,1/2位置。该有序相单胞尺寸为:(a_M,c_M分别为马氏体单胞的a和c轴长度),它与母相完全共格,位向关系为(001)_Ⅰ∥(001)_M,[100]_Ⅰ∥[110]_M。根据γ′-Fe_xC(Ⅰ)晶体结构计算出的有序相衍射花样与实验得到的衍射花样全部吻合。  相似文献   
4.
The temperature dependence of Young's modulus and internal friction (Q−1)in alumina, silicon nitride, and partially stabilized zirconia (Y-PSZ) ceramics was studied. Little change in Q−1 was found for alumina, whereas Q−1 for silicon nitride ceramics increased above 700°C. The Q−1 of Y-PSZ increased markedly with increasing temperature up to a peak at ∼200°C.  相似文献   
5.
We present a method to control the phase of an optical lattice according to an external trigger signal. The method has a latency of less than 30 μs. Two phase locked digital synthesizers provide the driving signal for two acousto-optic modulators which control the frequency and phase of the counter-propagating beams which form a standing wave (optical lattice). A micro-controller with an external interrupt function is connected to the desired external signal, and updates the phase register of one of the synthesizers when the external signal changes. The standing wave (period λ/2 = 390 nm) can be moved by units of 49 nm with a mean jitter of 28 nm. The phase change is well known due to the digital nature of the synthesizer, and does not need calibration. The uses of the scheme include coherent control of atomic matter-wave dynamics.  相似文献   
6.
7.
This paper presents an extension to the existing dynamic relaxation method to include equality constraint conditions in the process. The existing dynamic relaxation method is presented as a general, gradient‐based, minimization technique. This representation allows for the introduction of the projected gradient, discrete parallel transportation and pull back operators that enable the formulation of the geodesic dynamic relaxation method, a method that accounts for equality constraint conditions. The characteristics of both the existing and geodesic dynamic relaxation methods are discussed in terms of the system's conservation of energy, damping (viscous, kinetic, and drift), and geometry generation. Particular attention is drawn to the introduction of a novel damping approach named drift damping. This technique is essentially a combination of viscous and kinetic damping. It allows for a smooth and fast convergence rate in both the existing and geodesic dynamic relaxation processes. The case study was performed on the form‐finding of an iconic, ridge‐and‐valley, pre‐stressed membrane system, which is supported by masts. The study shows the potential of the proposed method to account for specified (total) length requirements. The geodesic dynamic relaxation technique is widely applicable to the form‐finding of force‐modeled systems (including mechanically and pressurized pre‐stressed membranes) where equality constraint control is desired. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
8.
This paper proposes a system identification method for linear systems with time delay and unknown order. We hypothesize a number of candidate models, which have different order, because system order is unknown. In each model, we estimate the model parameters based on the maximum likelihood method by using nonlinear optimization technique. Then both local optimization technique and global search method are used because the estimated parameters may fall into a local minimum. After all candidate model's parameters are estimated, one model is selected among these models to estimate the system order by using a posteriori probability based on Bayes's theorem. Finally, the validity of the proposed method is demonstrated by numerical examples. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 145(3): 61–68, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10166  相似文献   
9.
Measured skin potential activity under waking conditions in 2 experiments with a total of 60 rats, 21 cats, 40 nonhuman primates, and 87 normal adult humans. In agreement with findings of previous researchers, skin potential response waveform was always monophasic negative in rats and cats, but in humans it took 3 forms. By contrast, it was always monophasic positive in simian nonhuman primates, although prosimiae gave monophasic negative waves. A relationship between skin potential level and skin potential response could not be observed in any S except humans. From these results, an attempt was made to relate skin potential activity to the peripheral mechanism involved in these species based on a phylogenetic viewpoint. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
We present here the analysis of the early and late multiwavelength afterglow emission, as observed by Swift a small robotic telescope and very large telescope (VLT). We compare early observations with late afterglow observations obtained with Swift and the VLT and we observe an intense rebrightening in the optical band at about 1 day after the burst, which is not present in the X-ray band. The lack of detection in X-ray of such a strong rebrightening at lower energies may be described with a variable external density profile. In such a scenario, the combined X-ray and optical observations allow us to derive that the matter density located at approximately 1017 cm from the burst is approximately a factor of 10 higher than in the inner region. This is the first time in which a rebrightening has been observed in the optical afterglow of a gamma-ray burst that is clearly absent in the X-ray afterglow.  相似文献   
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