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111.
Volcanic disasters can cause severe loss of human life and damage to property. The main damage is caused during an eruption and from subsequent erosion of deposited materials. Heavy rainfall in volcanic areas erodes volcanic deposits, mainly pyroclastic flows and ash fall deposits, which flow as lahar to the foothill of the mountain and cause drastic damage to economically important areas. This post-eruption disaster becomes complex due to the occurrence of stream captures and watershed breakouts that lead to devastating lahars. Continuous monitoring of such geomorphic and hydrologic changes is necessary to cope with changing hazard conditions. Therefore it is important to update the watershed boundaries in order to study current hazard conditions and develop mitigation plans for future disasters. Changes of geomorphic and watershed boundary have occurred in the Mayon Volcano in the Philippines mainly as a result of a major volcanic eruption of 1993, due to which mitigation structures were constructed and modified in the low lying areas. In this study interferometry was used to develop DEM from SAR data to delineate watershed boundaries. New lava flows, pyroclastic flows and lahar deposits in the watersheds were mapped using elevation changes, coherence and intensity derived from the SAR images. Updating geomorphic features of the watersheds and their boundaries using SAR provides a new weather independent alternative technique for monitoring the effect of volcanic activity. 相似文献
112.
Toshio Honda 《Sequential Analysis》2013,32(1):73-89
Let X1, X2... be i.i.d. observations with mean μ and variance σ2, and suppose that given a sample of size n one wishes to estimate μ by Xn, subject to the loss function Ln= A2(Xn-μ)2+n. When σ2 is unknown, the optimal sample size n0 for minimizing the risk Rn = E{Ln} cannotbe found. To resolve this problem, Robbins (1959) proposed a sequential procedure whenXi is normally distributed, and then the asymptotic properties have been extensively studied. In this paper, we apply Hall's three stage procedure to the problem without specifying the distribution of Xi and derive the second order asymptotic expansions of the expected sample size and the risk. 相似文献
113.
Toshio Honda 《Sequential Analysis》2013,32(3-4):239-251
Suppose that {Xn} is a strongly mixing process with unknow marginal density f(x) and that we estimate f(x) by a kernel estimator [fcirc]n(x|hn)and want to achive the MISE no larger than some preassigned postive number w. However,the appropriate sample size n*depends on a functional of the unknow density function. Therefore some sequential procedure is required and we adopt a fully sequential procedure. In this paper we investigate the asymptotic properties of the procedure and show that the producure is asymptotically efficient in a certain sense as w→0. The results are almost the same in the i.i.d. setting. our result extend a class of models to which the methodology can be applied. For example economic variable,experiments on a single subject in which obervation are not indepent, and so on. 相似文献
114.
Destruction of volatile organic compounds used in a semiconductorindustry by a capillary tube discharge reactor 总被引:1,自引:0,他引:1
Kohno H. Berezin A.A. Jen-Shih Chang Tamura M. Yamamoto T. Shibuya A. Honda S. 《Industry Applications, IEEE Transactions on》1998,34(5):953-966
Nonthermal plasma technologies offer an innovative approach to the problem of decomposing various volatile organic compounds (VOCs). The authors focused on DC capillary tube discharge plasma reactors to study the decomposition/destruction efficiency for toluene, EGM, trichloroethane and trichloroethylene at 50-2300 ppm levels in dry air. The effects of gas flow rate, VOC concentration and reactor operating conditions on decomposition and analysis of reactant conversion for each VOC were investigated. The results show that VOC destruction efficiency as high as 90% can be achieved, even under a short residence time (3.8 ms) with a destruction energy efficiency of up to 95 g (VOC)/kWh. Laboratory-scale plasma technology was successfully demonstrated for its potential application for VOC control in the semiconductor clean-room environment 相似文献
115.
To understand the cause of read/write error due to lube accumulation, a model to simulate the slider’s response to the contact impact, which can occur between a lubricant droplet on the disk and a slider, was developed. The contact impact model is based on the water-hammer pressure model with an additional damping force, where the wave-shock pressure is assumed to function as the contact pressure, and the damping force defines the damping characteristics of the impact which are due to the lubricant’s high viscosity and squeeze between the droplet and slider contact area along the slider local velocity direction. The transient contact impact is dependent on lube droplet density, disk velocity, pitch angle of the slider, and contact area between the droplet and the slider. The measured read/write signal jump due to lube pickup can be explained by the simulation results. This modeling and simulation are helpful to us in understanding the read/write signal loss due to a lube droplet at head disk interface. 相似文献
116.
117.
Keiichi Honda Nanao Hayashi Fumiko Abe Tatsuo Yamauchi 《Journal of chemical ecology》1997,23(7):1703-1713
A giant danaid butterfly, Idea leuconoe, specializes on apocynaceous plants such as Parsonsia laevigata, which has been reported to contain pyrrolizidine alkaloids. Females of I. leuconoe deposited eggs in response to methanolic extract of P. laevigata, and subsequent bioassay-guided fractionation of the extract revealed that phytochemicals crucial for host recognition by ovipositing females are Parsonsia-specific macrocyclic pyrrolizidine alkaloids including parsonsianine, parsonsianidine, and 17-methylparsonsianidine. Parsonine, another P. laevigata pyrrolizidine component with a keto-dihydropyrrolizine moiety that is closely related in structure to male pheromones of the butterfly, and several nonhost pyrrolizidine alkaloids were entirely inactive. We interpret these data as strong evidence for an ancestral association through herbivory between danaid butterflies and pyrrolizidine alkaloids. 相似文献
118.
The synergistic effect of methyltrioctylammonium chloride (QCI) on the extraction of Np(V) by 1-phenyl-3-methyl-4-benzoyl-pyrazolone(HP) in benzene is studied over the pH range 2-6. This system extracts Np(V) better than any previously reported. The interaction of the extractants and monomer-dimer equilibria affect the distribution behavior of Np(V) in a complicated manner. Analysis of the results suggests that NpO2 + (M+) is extracted as mixed dimers, (QMP2QCl)o and (QMP2QP)o. 相似文献
119.
K. Proke Th. Wand A.V. Andreev M. Meissner F. Honda V. Sechovský 《Journal of Alloys and Compounds》2008,460(1-2):47-53
Specific heat of a single crystalline URhSi was measured by a relaxation method in a temperature range 0.3–25 K in magnetic fields up to 8 T applied along the two of the principal axes. The low-temperature specific heat exponentially decays with magnetic field. The decay is much faster in fields applied along the easy magnetization direction (the c-axis) than for the hard axis (the a-axis) case. A strong upturn in cp/T versus T below 0.6 K that disappears with application of magnetic field is observed suggesting possible magnetic or superconducting phase transition at lower temperatures. The electrical resistivity in the vicinity of the ferromagnetic phase temperature is found to be reduced by more than 50% upon application of magnetic field of 8 T applied along the c-axis. URhSi represent an itinerant ferromagnetic system with influence of spin fluctuations. 相似文献
120.
This paper studies the following variant of the Vehicle Routing Problem that we call the Grasp and Delivery for Moving Objects (GDMO) problem, motivated by robot navigation: The input to the problem consists of n products, each of which moves on a predefined path with a fixed constant speed, and a robot arm of capacity one. In each
round, the robot arm grasps one product and then delivers it to the depot. The goal of the problem is to find a collection
of tours such that the robot arm grasps and delivers as many products as possible. In this paper we prove the following results:
(i) If the products move on broken lines with at least one bend, then the GDMO is MAXSNP-hard, and (ii) it can be approximated
with ratio 2. However, (iii) if we impose the “straight line without bend” restriction on the motion of every product, then
the GDMO becomes tractable.
Y. Asahiro’s research was supported in part by Grant-in-Aid for Young Scientists 15700021, and Research on Priority Areas
16092223.
E. Miyano’s research was supported in part by Grant-in-Aid for Research on Priority Areas 16092223.
Presently, S. Shimoirisa is with the Software Development Engineering Department, Products Development Center, Retail Information
Systems Company, Toshiba TEC Corporation. 相似文献