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31.
This paper considers a multiobjective linear programming problem involving fuzzy random variable coefficients. A new fuzzy random programming model is proposed by extending the ideas of level set-based optimality and a stochastic programming model. The original problem involving fuzzy random variables is transformed into a deterministic equivalent problem through the proposed model. An interactive algorithm is provided to obtain a satisficing solution for a decision maker from among a set of newly defined Pareto optimal solutions. It is shown that an optimal solution of the problem to be solved iteratively in the interactive algorithm is analytically obtained by a combination of the bisection method and the simplex method. 相似文献
32.
The statistical information processing can be characterized by the likelihood function defined by giving an explicit form
for an approximation to the true distribution. This mathematical representation, which is usually called a model, is built
based on not only the current data but also prior knowledge on the object and the objective of the analysis. Akaike2,3) showed that the log-likelihood can be considered as an estimate of the Kullback-Leibler (K-L) information which measures
the similarity between the predictive distribution of the model and the true distribution. Akaike information criterion (AIC)
is an estimate of the K-L information and makes it possible to evaluate and compare the goodness of many models objectively.
In consequence, the minimum AIC procedure allows us to develop automatic modeling and signal extraction procedures. In this
article, we give a simple explanation of statistical modeling based on the AIC and demonstrate four examples of applying the
minimum AIC procedure to an automatic transaction of signals observed in the earth sciences.
Genshiro, Kitagawa, Ph.D.: He is a Professor in the Department of Prediction and Control at the Institute of Statistical Mathematics. He is currently
Deputy Director of the Institute of Statistical Mathematics and Professor of Statistical Science at the Graduate University
for Advanced Study. He obtained his Ph.D. from the Kyushu University in 1983. His primary research interests are in time series
analysis, non-Gaussian nonlinear filtering, and statistical modeling. He has published over 50 research papers. He was awarded
the 2nd Japan Statistical Society Prize in 1997.
Tomoyuki Higuchi, Ph.D.: He is an Associate Professor in the Department of Prediction and Control at the Institute of Statistical Mathematics. He
is currently an Associate Professor of Statistical Science at the Graduate University for Advanced Study. He obtained his
Ph.D. from the University of Tokyo in 1989. His research interests are in statistical modeling of space-time data, stochastic
optimization techniques, and data mining. He has published over 30 research papers. 相似文献
33.
This paper deals with model following control of a model helicopter with three degree-of-freedom. Since the decoupling matrix
is singular, a nonlinear structure algorithm is used to design the controller. Furthermore, since the model dynamics are described
linearly by unknown system parameters, a well-known parameter estimation technique is introduced. The integral type of estimation
model is proposed here since the use of the derivative type of model cannot obtain the desired estimation result. The experimental
results show the effectiveness of the proposed method.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
34.
Khairul Salleh Hiroaki Seki Yoshitsugu Kamiya Masatoshi Hikizu 《Artificial Life and Robotics》2008,12(1-2):142-147
Manipulating deformable objects like clothes, plastic, and paper by a robot is very challenging. This paper focuses on clothes
manipulation as an example. A tracing manipulation method is used here to find a corner of the clothes. In this paper, tracing
refers to tracing the clothes’ edge, with the robot’s movement based on feedback from sensors. One difficulty during this
edge tracing is to make the robot trace smoothly and speedily without dropping the clothes in the process. This is due to
the fact that deformable objects are sensitive to contact forces. A solution to this problem is to design a special robot
gripper that can trace the clothes without having to worry about the clothes slipping away. In this paper, the development
of inchworm-type grippers is proposed. Two sets of grippers inside a robot hand will allow the robot to trace the clothes
more freely because there will always be a gripper firmly holding the clothes at any time. A unique tracing method for towel
spreading using the inchworm grippers is also discussed. Experimental results have demonstrated the effectiveness of both
the proposed grippers and also the algorithm.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
35.
Because functional diseases of the brain can cause disabilities related to human movement control, a compensation method was
developed for improving the performance of hand movements. The compensation for human hand movements can be carried out by
adding an assistant force that is generated from artificial equipment attached to a human arm. From the experiment on visual
target tracking, it was found that the tracking trajectory was adequately represented by a dynamic model of the motion of
an articulated industrial robot arm, and the different abilities for movement control among healthy people and patients were
classified by different model parameters as position loop gain, velocity loop gain, and response delay. Dynamic force compensation
was approached by considering the different control features of the patients. The effectiveness of the proposed compensation
method was verified in a simulation study on an actual industrial robot arm. A human-machine interface, e.g., a brain-computer
interface (BCI), for realizing the control of artificial equipment to compensate for human hand movements is also presented
and discussed. 相似文献
36.
Effect of heparin on high glucose induced proliferation and expression of matrix metalloproteinases in normal human mesangial cells 总被引:1,自引:0,他引:1
Zhou Qiao-ling Yasumoto Yuichiro Tsukamoto Masatoshi Nozaki Tsuyoshi Sogabe Atsushi Harada Kouji Zhang Yi-xiang Lin Xiao-yan Zhang Yang-de Arima Terukatsu 《中南工业大学学报(英文版)》2005,12(1):359-364
Background The pathogenesis of diabetic nephropathy (DN) is a complex pathophysiological process. Its precise mechanism is not fully
known. In recent years it has been recognized that synthesis of various extracelluar matrix (ECM) components may increase,
and that degradation of ECM may decrease in DN. It was reported heparin could inhibit mesangial cells proliferation in vitro.
The main aim of this study is to explore whether heparin inhibits proliferation of mesangial cells grown in high glucose concentration
and to measure the effect of heparin on matrix metalloproteinases (MMPs) expression in mesangial cells. Methods The medium contained either low glucose (5 mmol/L) or high glucose (25 mmol/L). The concentrations of heparin in the culture
medium were 0, 25, 50, 100, 200 or 400 μg/mL. A metabolic (WST-1) assay was used to measure mesangial cell proliferation and
Western blot analysis was used to measure MMPs expression of mesangial cells. Results Normal human mesangial cell (NHMC) proliferation was higher in high glucose (HG) medium than in low glucose (LG) medium.
They showed a 1.93 fold expansion after 72 h in high glucose in contrast to a 1.63 fold expansion in low glucose. In the presence
of heparin, mesangial cells proliferation was inhibited, which was more obvious at high glucose concentrations than at low
glucose concentrations. In high glucose, with heparin concentration of 50, 100, 200 and 400 μg/mL, the mesangial cells showed
a 0.61 fold, 0.52 fold, 0.52 fold and 0.41 fold reductions in cell number compared to cells grown without heparin. In low
glucose, only concentrations of 200 μg/mL and 400 μg/mL showed reduction in cell number, namely 0.54 fold and 0.45 fold, when
compared to cells grown without heparin. In Western blot analysis, MMP1, MMP2, MMP3 and MMP9 was expressed by mesangial cells expressed in both high and low glucose concentrations, which was more prominent in high
glucose medium. Incubation of heparin further increased expression of MMP1, MMP2, MMP3 and MMP9. Conclusions This study suggests that glucose can accelerate mesangial cell proliferation while heparin can reduce proliferation, being
more obvious at high glucose concentrations. Higher glucose concentrations led to increased MMP expression, which may take
part in the regulation of mesangial matrix synthesis and degradation. Addition of heparin resulted in a corresponding increase
in MMP expression, most notably at high glucose concentrations, indicating a potentially renoprotective role in DN.
Foundation item: Project (30370663) supported by the National Natural Science Foundation of China 相似文献
37.
It has been said that nuclear energy is an important option for especially developing countries to satisfy their increasing energy demand. However, it will be difficult to deploy first of a kind nuclear power plant in developing countries because extensive safety demonstration has to be conducted in industrialized countries. On the other hand, it will be essential to present rigid proof of reliable operational experience to develop proper understanding of the safety features of new reactor systems among the people around the demonstration plant sites. One of the ways to solve the issue is to integrate existing technologies supported by a great deal of data and experience into a new reactor design. Based on the consideration, a small-sized district heating reactor system based on the pressurized water reactor (PWR) technologies combined with the fuel concept of high temperature gas cooled reactors (HTGRs) has been studied. The purpose of the combination of these two existing concepts is to take the best advantages of both excellent operational experience of PWRs and the integrity of HTGR fuel, coated particle fuel, against fission products release even at high temperature. We expect that this approach will help create a breakthrough to the current stagnation of nuclear power deployment. 相似文献
38.
Koichi Uozumi Masatoshi Iizuka Tadashi Inoue Takashi Iwai 《Journal of Nuclear Materials》2004,325(1):34-43
Experiments were conducted on simultaneous recovery of uranium and plutonium electrochemically into laboratory scale liquid cadmium cathodes (LCCs) at different U/Pu ratios in the salt phase, and the influence of the salt composition on the recovered amounts of uranium and plutonium, the morphologies of uranium and plutonium in the LCC, and the behavior of americium, which is present as a decay product of plutonium-241, were examined. As a result, it was shown that there is a threshold in the U/Pu ratio in the salt phase between 1/4.3 and 1/1.73 for the successful simultaneous recovery of uranium and plutonium up to 10 wt% in the LCC at high current efficiencies. In the LCC, uranium and plutonium existed in the forms of intermetallic compounds, (U, Pu)Cd6 and (U, Pu)Cd11, and also pure uranium metal. It was also revealed that americium associates with plutonium according to the separation factor during the LCC operation. 相似文献
39.
Estimations have been made, resulting in a general method for the prediction of the incubation time for cavitation erosion using various cavitating conditions and materials. From a single erosion test, the incubation time can be estimated for various conditions and materials by plotting the mass loss as a function of exposure time to cavitation on a log–log scale. 相似文献
40.