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121.
Wireless body sensor networks (WBSNs) enable a broad range of applications for continuous and real‐time health monitoring and medical assistance. Programming WBSN applications is a complex task especially due to the limitation of resources of typical hardware platforms and to the lack of suitable software abstractions. In this paper, SPINE (signal processing in‐node environment), a domain‐specific framework for rapid prototyping of WBSN applications, which is lightweight and flexible enough to be easily customized to fit particular application‐specific needs, is presented. The architecture of SPINE has two main components: one implemented on the node coordinating the WBSN and one on the nodes with sensors. The former is based on a Java application, which allows to configure and manage the network and implements the classification functions that are too heavy to be implemented on the sensor nodes. The latter supports sensing, computing and data transmission operations through a set of libraries, protocols and utility functions that are currently implemented for TinyOS platforms. SPINE allows evaluating different architectural choices and deciding how to distribute signal processing and classification functions over the nodes of the network. Finally, this paper describes an activity monitoring application and presents the benefits of using the SPINE framework. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
122.
Robotics has recently been introduced in surgery to improve intervention accuracy, to reduce invasiveness and to allow new surgical procedures. In this framework, the ROBOCAST system is an optically surveyed multi-robot chain aimed at enhancing the accuracy of surgical probe insertion during keyhole neurosurgery procedures. The system encompasses three robots, connected as a multiple kinematic chain (serial and parallel), totalling 13 degrees of freedom, and it is used to automatically align the probe onto a desired planned trajectory. The probe is then inserted in the brain, towards the planned target, by means of a haptic interface. This paper presents a new iterative targeting approach to be used in surgical robotic navigation, where the multi-robot chain is used to align the surgical probe to the planned pose, and an external sensor is used to decrease the alignment errors. The iterative targeting was tested in an operating room environment using a skull phantom, and the targets were selected on magnetic resonance images. The proposed targeting procedure allows about 0.3 mm to be obtained as the residual median Euclidean distance between the planned and the desired targets, thus satisfying the surgical accuracy requirements (1 mm), due to the resolution of the diffused medical images. The performances proved to be independent of the robot optical sensor calibration accuracy.  相似文献   
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124.
Scientometrics - The quantitative evaluation of Social Science and Humanities (SSH) and the investigation of the existing similarities between SSH and Life and Hard Sciences (LHS) represent the...  相似文献   
125.
The deformation of wood is analyzed using the finite element method to quantify the phenomena in wood cells and cell walls. The deformation curves of computed microstructures are compared to experimental observations in two different loading cases: compression and combination of shear and compression. Simulated and experimental shapes of deformation curves match qualitatively and the deformation shapes exhibit a similar response to change in the loading mode. We quantify the intra-cell-wall stresses to understand the effects of the different layers during the deformation. The results benefit the development of energy efficient mechanical and chemo-mechanical pulping processes for pulp, board, and composite manufacture. In addition, the aspects of cell deformation can be exploited to dismantle the wood to accelerate chemical reactions in biorefinery.  相似文献   
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127.
Glucosinolates in different ecotypes of Brassica rapa L. subsp. sylvestris L. Janch. var. esculenta Hort. widely distributed in Southern Italy and locally known as “friariello” and “cima di rapa”, were characterized and their glucosinolate composition was compared with that of broccoli (Brassica oleracea L. var. italica).  相似文献   
128.
This work proposes a simple model to simulate the dynamics of the market related to COTS software products, when there are no new entrants. The model takes in explicit account the interactions between products. The model uses a set of random variables, as the initial condition, to simulate the time evolution. The results of the simulations predict the emergence of monopolies, when the interactions between products are significant, and of open markets, when they are limited. The model is validated, by comparing the results of the simulation with the well established observations related to software markets and by comparing the resulting distribution of COTS software products with real data on the software market, which was provided by PC Data Inc.  相似文献   
129.
Our era is witnessing an increasing impact of globalization on self and identity and at the same time a growing uncertainty. The experience of uncertainty motivates individuals and groups to find local niches for identity construction. This article's central tenet is that the processes of globalization and localization, as globalization's counterforce, require a dialogical conceptualization of self and identity in which global and local voices are involved in continuous interchanges and negotiations. This tenet is elaborated along 2 lines of argument. First, 3 factors are described as crucial to understanding the processes of globalization and localization on the individual level: the increasing number of voices and countervoices, the role of social power, and the role of emotions. Second, the authors argue that the apparent tension between the widening horizons of globalization and the need for local niches requires acknowledgment of the pervasive influence of biologically based needs for stability, safety, and security. Finally, the authors propose studying self and identity on 3 levels--individual, local, and global--and some lines of research at the interface of these levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
130.
Juniper (Juniperus oxycedrus) is used in European cuisine for its distinguishing flavour. J. oxycedrus ssp. oxycedrus berry and wood essential oils were tentatively identified by GC and GC/MS. Fifty compounds were identified in the berry oil and 23 compounds were identified in the wood oil. The J. oxycedrus ssp. oxycedrus berry oil was characterised by high contents of α-pinene (27.4%) and β-myrcene (18.9%). Other important compounds were α-phellandrene (7.1%), limonene (6.7%), epi-bicyclosesquiphellandrene (2.3%) and δ-cadinene (2.2%) while, in the wood oil, δ-cadinene (14.5%) is a major main component, together with cis-thujopsene (9.2%) and α-muurolene (4.9%). In vitro evaluation of antioxidant activity by the DPPH method showed a significant activity for both oils with IC50 values of 1.45 μl/ml for wood and 7.42 μl/ml for berries. Hypoglycaemic activity was investigated through the inhibition of α-amylase. The results revealed that oil obtained by hydrodistillation from J. oxycedrus ssp. oxycedrus wood exhibits an interesting activity with IC50 of 3.49 μl/ml.  相似文献   
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