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111.
The impact of removing the rind from fresh‐cut watermelon slices was assessed on the quality of the product during storage at 4 °C for 9 days. Flesh lycopene declined from 55.4 to 47.9 mg kg?1 f.w. and colour lightness (L*) increased from 43.2 to 45.8 after 2 days of storage. Initial heart and placental flesh firmness increased from 7.3 and 9.8 N, respectively, to 9.5 and 12.8 N after 9 days, but were unaffected by rind processing. Electrolyte leakage from placental tissue was unaffected by storage and rind. Rind presence limited juice run‐off by 47.2% and maintained mean total soluble sugar concentration in the slices at 86.0 mg mL?1 as opposed to 76.8 mg mL?1 in rind‐less slices. Change in the quality was most pronounced between 0 and 2 day of storage. Removing the rind accelerated senescence and off‐flavour production, while the presence of rind improved the overall storage stability of fresh‐cut watermelon slices.  相似文献   
112.
From the mechanical point of view, the particularity of masonry structures stems from the fact that the structural system is hard to be modeled by the classical Continuum Mechanics approach. The problem gets more complicated when imperfections, such as cracks are present. An example of a single multi-drum column, with fractured drums, is studied herein, using the Distinct Element Method (DEM). The purpose of the research is the investigation of the impact of the fractures to the overall stability of the structure. The 3D DEM numerical results are explained on the basis of simple 2D analytical considerations. The shear and normal crack deformation is monitored and the minimum required strength of the crack interface is quantified. An experimental program of direct shear tests is set in order to estimate the strength of the marble–cement interface. The experimental values are compared to the minimum required from the numerical analysis.  相似文献   
113.
Changes in urokinase-plasminogen activator (u-PA) and u-PA receptor (u-PAR) expression at the protein and mRNA level in resting neutrophils and in neutrophils activated by phorbol myristate acetate (PMA) were examined. Low amounts of u-PA were found intracellularly or membrane-bound in resting neutrophils. However, incubation of resting neutrophils with purified exogenous u-PA (10 IU/ml) revealed extensive binding of u-PA to cell membranes. Excess amino-terminal fragment of the u-PA molecule, a proteolytically inactive fragment of u-PA (amino acids 1-135) blocked binding of exogenous u-PA to the cell membrane. These results, collectively, indicate that the binding of u-PA is specific and that resting neutrophils have unoccupied u-PA receptors on their cell membrane. Addition of PMA led to an increase (P < 0.01) in total cell-associated, membrane-bound u-PA activity and u-PA mRNA expression by bovine neutrophils. In contrast. PMA increased u-PAR mRNA levels but this was accompanied by a decrease (2.5-fold; P < 0.01) in free, unoccupied u-PA binding sites. No significant effects on total cell-associated or membrane-bound u-PA were found when neutrophils were treated with 4-phorbol 12,13 didecanoate, a phorbol ester that does not activate protein kinase C (PKC). Furthermore, addition of 1-(5-isoquinolinesylphonyl)-2-methlylpiperazine dihydrochloride (H-7), a potent PKC inhibitor, blocked the effect of PMA on total cell-associated u-PA activity. Thus, PKC plays a role in the modulation of u-PA and u-PAR by PMA in bovine neutrophils.  相似文献   
114.
This paper focuses on various coevolutionary robotic experiments where all parameters except for the fitness function remain the same. Initially an attempt to categorize coevolutionary experiments is made and subsequently three experiments of competitive coevolution (hunt, battle and mating) are presented. The experiment concerning implicit competition of two species (mating) is given special attention as it shows emergence of compromise and collaboration through a competitive environment. The co-evolution progress monitoring is evaluated through fitness graphs, CIAO and Hamming maps and the results are interpreted for each experimental setup. The paper concludes that despite the alteration of fitness functions, several evasion–pursuit elements emerge. Furthermore, conciliatory strategies can emerge in implicit competitional cases.  相似文献   
115.
116.
We present an efficient parameterized algorithm for the (k,t)-set packing problem, in which we are looking for a collection of k disjoint sets whose union consists of t elements. The complexity of the algorithm is O(2O(t)nNlogN). For the special case of sets of bounded size, this improves the O(k(ck)n) algorithm of Jia et al. [J. Algorithms 50 (1) (2004) 106].  相似文献   
117.
The prediction of ground level ozone for air quality monitoring and assessment is simulated through an integrated system of gridded models (meteorological, photochemical), where the atmosphere is represented with a three-dimensional grid that may include thousands of grid cells. The continuity equation solved by the Photochemical Air Quality Model (PAQM) reproduces the atmospheric processes (dynamical, physical, chemical and radiative), such as moving and mixing air parcels from one grid cell to another, calculating chemical reactions, injecting new emissions. The whole modeling procedure includes several sources of uncertainty, especially in the large data sets that describe the status of the domain (boundary conditions, emissions, chemical reaction rates and several others). The robustness of the photochemical simulation is addressed in this work through the deterministic approach of sensitivity analysis. The automatic differentiation tool ADIFOR is applied on the 3D PAQM CAMx and augments its Fortran 77 code by introducing new lines of code that additionally calculate, in only one run, the gradient of the solution vector with respect to its input parameters. The applicability of the approach is evaluated through a sensitivity study of the modeled concentrations to perturbations at the boundary conditions and the emissions, for three essentially dissimilar European Metropolises of the Auto-Oil II programme (Athens, Milan, and London).  相似文献   
118.
This paper presents the detailed performance analysis for a colour photometric stereo system proposed recently. The system recovers surface colour and surface normal for each surface patch separately, in the presence of highlights and shadows. The error analysis presented concerns every step of the algorithm, and it is based on the assumptions that errors may arise due to Gaussian image noise and errors in the accuracy with which the geometry of the illuminating set-up is known. The analysis is confirmed by experiments. The implications of this sensitivity analysis to the design of such a rig and the choice of threshold values for the algorithm are also discussed and recommendations to a designer are given.  相似文献   
119.
从明暗恢复形状是计算机视觉领域中的经典病态问题,传统方法是通过引入光滑约束等条件来获得问题的解,但传统方法存在因过平滑而失真的缺点。针对传统方法恢复结果的局限性,提出了一种基于分形约束的从明暗恢复形状的新算法,该方法首先给出分形约束条件,之后结合反射图线性化与最小能量法来计算出曲面高度。该方法不仅克服了传统算法因基于光滑假设所造成的恢复结果过分平滑而失真的缺点,且不需要可积性的约束条件,也不需要对边界条件的假设,实验结果表明,该方法用于自然景物的三维表面重构,可获得比传统方法更好的恢复效果。  相似文献   
120.
Occlusion Culling Algorithms: A Comprehensive Survey   总被引:1,自引:0,他引:1  
In this paper, occlusion culling techniques that appeared in the last decade are reviewed. Occlusion culling techniques are responsible for reducing the polygons rendered by the graphics hardware with the target of achieving real-time rendering. The various techniques are discussed in detail and a synopsis table with their main characteristics is given.  相似文献   
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