全文获取类型
收费全文 | 150篇 |
免费 | 5篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 20篇 |
金属工艺 | 4篇 |
机械仪表 | 1篇 |
建筑科学 | 9篇 |
能源动力 | 14篇 |
轻工业 | 9篇 |
水利工程 | 1篇 |
无线电 | 10篇 |
一般工业技术 | 58篇 |
冶金工业 | 3篇 |
自动化技术 | 23篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 5篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 8篇 |
2015年 | 5篇 |
2014年 | 7篇 |
2013年 | 15篇 |
2012年 | 10篇 |
2011年 | 13篇 |
2010年 | 10篇 |
2009年 | 13篇 |
2008年 | 5篇 |
2007年 | 10篇 |
2006年 | 4篇 |
2004年 | 1篇 |
2003年 | 5篇 |
2002年 | 1篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1996年 | 4篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 2篇 |
排序方式: 共有156条查询结果,搜索用时 31 毫秒
51.
Sallai Ben-Oumrane Tounsi Abedlouahed Mechab Ismail Bachir Bouiadjra Mohamed Meradjah Mustapha Adda Bedia El Abbas 《Computational Materials Science》2009,44(4):1344-1350
In this paper, an elastic, rectangular, and simply supported, sigmoid functionally graded material (S-FGM) beam of thick thickness subjected to uniformly distributed transverse loading has been investigated. The S-FGM system consists of ceramic (Al2O3) and metal (Al) phases varying through the thickness of beam. Major classes of representative theories such as classical laminate beam theory (CLBT), first-order shear deformation theory (FSDT) and high-order theories (HOTs) have been considered and a unified kinematic formulation is then proposed. The Poisson’s ratio of the thick S-FGM beam is assumed to be constant, but their Young’s moduli vary continuously throughout the thickness direction according to the volume fraction of constituents defined by sigmoid function. The numerical illustrations concern bending response of S-FGM rectangular beams. Qualitative and quantitative assessments of displacement and stress fields have been presented and discussed. 相似文献
52.
B. Mechab B. Serier B. Bachir Bouiadjra K. Kaddouri X. Feaugas 《International Journal of Pressure Vessels and Piping》2011
In this paper, the J integral was calculated for semi-elliptical surface cracks in pipes under bending using three-dimensional finite element analysis. The computations were performed for elastic and elastic-plastic behaviours. For the elastic case, the numerical results allowed the extrapolation of shape functions for analytical determination of the J integral. The results are in a good agreement with those in the literature if the ratio between the radius and the thickness of the pipe (R/t) is from 1 to 10. The analysis was extended to values of the ratio R/t higher than 10. For the elastic-plastic, the numerical results are in good agreement with the analytical solution found in the literature for thick pipes (R/t ≥ 10). The effect of the ratio R/t becomes sensible when the ratio of the applied moment to the moment of reference (M/Mor) exceeds 0.9. 相似文献
53.
Damir Cavka Basma Harrat Dragan Poljak Bachir Nekhoul Kamal Kerroum Khalil El Khamlichi Drissi 《Engineering Analysis with Boundary Elements》2011,35(10):1101-1108
The paper deals with transient analysis of grounding grids using two different approaches, wire antenna theory and modified transmission line model. The Pocklington integro-differential equations, in frequency domain, arising from the wire antenna theory are numerically handled via the Galerkin–Bubnov variant of indirect Boundary Element Method (GB-IBEM), while the transient response was obtained using inverse Fourier transform. The modified transmission line equations are treated using the finite difference time domain (FDTD) method. Some illustrative numerical results are presented and discussed in the paper. 相似文献
54.
Bachir Dadda Saïd Abboudi Rida Zarrit Abderrahmane Ghezal 《International Journal of Hydrogen Energy》2014
Water transport in the membrane of a PEM fuel cell is provided essentially by a convective force, resulting from a pressure gradient, an osmotic force, due to a concentration gradient and an electric force caused by the protons migration from the anode to the cathode. Through these three types of force the two-dimensional behavior of electric potential has been studied in this paper. The adopted model in this work is based on the assumption of single phase and multi-species flow, supposed two-dimensional and transient in a porous medium. The species conservation equation is coupled with the energy equation through the diffusion coefficient of water and the heat convective flux. The set of governing equations in the form of convection–diffusion problem has been solved numerically using the finite volume method. The obtained results show the transient two-dimensional effect of heat and mass transfer on the voltage variation within the membrane. 相似文献
55.
In this study, a new approach is applied to compare the performances of single sided and double-sided symmetric composite patch with circular shape for repairing cracked aircraft structures. This is an approach that consists to evaluate the mass gain eventually obtained by the use of double symmetric composite patch if the two patch configurations give the same stress intensity factor at the crack tip. The three-dimensional finite elements method is used to compute the stress intensity factor. The obtained results show that the use of the double patch technique leads to a significant reduction of the stress intensity at the crack tip. The mass gain eventually given by the double patch technique can be very significant and this gain depends on the patch shape and the adhesive properties. 相似文献
56.
A. Benhamena L. Aminallah B. Bachir Bouiadjra M. Benguediab A. Amrouche N. Benseddiq 《Materials & Design》2011
The goal of this work is to analyse the severity of semi-elliptical crack defects and to study the degree of damage in the poly-ethylene pipe in bending during the crack propagation. The semi-elliptical cracks are considered in this work located in different position in the wall of the pipe. The three finite element method based on the computation of the J integral was used to analyse the fracture behaviour of these structures. The effect of the position, shape and size of the crack on the J integral values was highlighted. The effects of strain rate and the temperature on the J integral values were also examined. The obtained results show that the strain rates have a strong influence on the J integral values especially for circumferential crack at higher bending moment. However, the energy for circumferential crack is more important compared to axial crack. The effect of the depth of the crack becomes important when the ratio (a/t) reaches a critical value of 0.6 (a/t = 0.6), especially when the ratio a/c is weak (semi-elliptical crack, a/c = 0.2) where the J integral values becomes independently of the crack depth, this conclusion is opposite to the above for the poly-ethylene pipe subjected to internal pressure. We recall finally, that the temperature effect on circumferential cracks behaviour is more important compared to the axial cracks at critical crack size (a/c = 0.2 and a/t = 0.6). It is also shown that in the wall of pipe, the internal cracks are more dangerous than the external cracks. 相似文献
57.
Ground liquorice roots were exposed to various doses (0, 5, 10, 15 and 20 kGy) of gamma radiation from a 60Co source. Irradiated and non‐irradiated samples were stored at room temperature. Microbial population, viscosity, concentrations of some minerals and the sensory properties of the extracts were evaluated after 0 and 12 months of storage. Tests carried out immediately after irradiation showed that the microbial count had been reduced and that the dose required to reduce the count by 1 log cycle (D10) was about 2 kGy. No effect was observed on the total dissolved solids in extracts of liquorice roots. Glycyrrhizinic acid concentration in the extracts and the viscosities of suspensions produced from irradiated roots were lower than those from non‐irradiated ones. Sensory evaluation indicated that there were no significant differences (P < 0.05) in colour, taste or flavour between extracts produced from irradiated and non‐irradiated roots. However, after 12 months of storage, some mineral ion (Na+, Ca2+ and K+) concentrations in extracts produced from irradiated roots were lower than in those from non‐irradiated ones; no significant differences (P < 0.05) in viscosity were found between suspensions of irradiated and non‐irradiated roots. © 2002 Society of Chemical Industry 相似文献
58.
This paper presents a unified framework for expressing and solving the different functional verification problems of the circuit designers. This approach is based on the synchronous data flow language Lustre that was originally designed for programming real-time systems. Lustre can be used to describe digital circuits at different abstraction levels and their environments, as well as to express the properties about the behavior of these circuits. Then, the verification tool Lesar associated with the language Lustre automatically handles the different verifications. 相似文献
59.
Sabrina Mezoued Senaa Kaouche Bachir Nekhoul Kamal Kerroum Khalil El Khamlichi Drissi Françoise Paladian 《电信纪事》2006,61(5-6):721-747
In this paper we propose a new formalism for the analysis of electromagnetic coupling between the lightning wave and a network of lines or cables. This approach allows obtaining currents and induced voltages directly on the set of lines or cables extremities. For this objective we use the current generators representation of the lightning wave. Then by a mathematical formulation based on the topological analysis of the network, we deduce a linear equation system which resolution leads directly to the currents and induced voltages. In order to confirm our theoretical work, we present a set of applications that allows validating this formalism. 相似文献
60.
M. Belhouari S. Gouasmi B. Bachir bouiadjra K. Kaddouri B. Serier 《Computational Materials Science》2008,43(4):924-929
In the present work the finite element method is used to analyze the effect of interaction between an interfacial crack and a microcrack in ceramic/aluminum bi-materials. The behaviour is analyzed by the determination of the J integral, the plastic zone at the tips of the interfacial crack and the microcrack. The effects of longitudinal and transversal distance between the tips of the two cracks and the rotation of the microcrack are examined. The obtained results allow us to deduce a correlation between the position of the microcrack and the J integral and the plastic zone.The obtained results shows that the J integral at the interfacial crack tip reaches a maximum value when the microcrack is moved in the vicinity of the interfacial crack. With this distance the effect of interaction is marked more; the stress field at the microcrack tip and that of the interfacial crack generates only one plastic zone at the interfacial crack tip. The maximum size of the plastic zone is localised at the interfacial crack tip. Those of the two tips of the microcrack are very weak and even negligible in front of the zone plasticized at the interfacial crack tip. 相似文献