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71.
The vehicle impoundment sanction in Israel is applicable to several violations, and authorizes police officers to impound a vehicle for period of 30 days, in addition to license suspension. This study examined the effects of vehicle impoundment on traffic-violations and road accidents in Israel, using both subjective and objective measures. A telephone survey was administered to 378 impounded drivers, examining their knowledge and support of the impoundment penalty, as well as the impoundment's effect on their daily life and subsequent driving behaviors. Survey results indicated most impounded drivers did not recognize the violations to which impoundment applies. Respondents described the impoundment experience as one, which interfered with a variety of daily life aspects, and eventually lead them to the adoption of safer driving behaviors. Additionally, data analysis of police records was performed on 1549 impounded drivers and 1354 controls with matching violations performed prior to the application of the impoundment regulation, comparing accident and traffic-violations involvement in the subsequent year. Results indicated that impoundment failed to yield a significant effect over subsequent accident involvement, compared to previous sanctions. A comparison of subsequent traffic-violations indicated lower rates of violations following impoundment as compared with previous sanctions. Specifically, drivers whose vehicle was impounded were less likely to commit traffic violations in the following year than drivers subjected to other sanctions. The results are explained according to psychological behavioral theories of punishment effectiveness. These findings provide further support for impoundment as a deterrent for several traffic-violations. 相似文献
72.
73.
Psammomys obesus (sand rat) is an appropriate model to highlight the development of hyperinsulinemia, insulin resistance, obesity, and diabetes.
This animal species, with genetically predetermined diabetes, acquires non-insulin dependent diabetes mellitus when exposed
to energy-rich diets. In the present study, we explored the possibility that glycation of LDL may occur in diabetes-prone
P. obesus and affect platelet and macrophage functions. The glycation of LDL, isolated from diabetic animals, was significantly (P<0.05) higher (40%) than that of control animals. The incubation of platelets with glycated LDL enhanced the reactivity of
platelets by 32–44% depending on the aggregating agents (thrombin, collagen, ADP). Furthermore, LDL derived from diabetic
rats were chemotactic for normal monocytes and stimulated the incorporation of [14C]oleate into cellular cholesteryl esters. The enhancement of platelet aggregation and cholesterol esterification in monocytes
may contribute toward the accelerated development of atherosclerotic cardiovascular disease in diabetic P. obesus animals. This study also illustrates the relevance of studying atherosclerosis in the P. obesus animal model, as it shows an increased tendency to develop dietinduced diabetes, which is associated with cardiovascular
disorders. 相似文献
74.
Kahn SM Behar E Kinkhabwala A Savin DW 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2002,360(1798):1923-1933
We provide a qualitative review of key X-ray spectral diagnostics of astrophysical plasmas. We begin with a brief discussion of the two major types of equilibria, collisional ionization and photoionization, and then consider the behaviour of hydrogen-like, helium-like, iron L-shell and iron K-shell transitions for these separate cases. Where possible, we discuss explicit examples using high-resolution spectra acquired by the grating instruments on the Chandra and XMM-Newton observatories. 相似文献
75.
We present a system that tracks an articulated body performing 3D movement with occlusions using a combination of cameras
and mirrors. By integrating cameras and mirrors we get a simultaneous coverage of almost every point on the target and avoid
occlusions. The suggested setup is much simpler and easier to handle compared to the equivalent, camera-based setup. Our tracking
algorithm is model-based, and errors in the model are treated using the bundle adjustment procedure. In order to deal with
the problem of feature visibility, each feature is set to be valid or invalid based on the model and on its expected appearance;
this ensures that the system always tracks a set of distinguishable features. The proposed algorithm was able to track targets
in 3D using the Gauss–Newton method to minimize geometric errors. We tested our setup by tracking the chameleon’s eyes. Tracking
the eyes of a chameleon can be considered as the estimation of the 3D pose of an articulated body, where the head of the chameleon
is considered as a rigid body, and each of the two eyes has additional two degrees of freedom. The algorithm proposed can
be easily expanded to cope with more complex objects. 相似文献
76.
Ofir Avni Francesco Borrelli Gadi Katzir Ehud Rivlin Hector Rotstein 《Autonomous Robots》2008,24(3):285-302
This paper presents a framework for visual scanning and target tracking with a set of independent pan-tilt cameras. The approach
is systematic and based on Model Predictive Control (MPC), and was inspired by our understanding of the chameleon visual system.
We make use of the most advanced results in the MPC theory in order to design the scanning and tracking controllers. The scanning
algorithm combines information about the environment and a model for the motion of the target to perform optimal scanning
based on stochastic MPC. The target tracking controller is a switched control combining smooth pursuit and saccades. Min-Max
and minimum-time MPC theory is used for the design of the tracking control laws.
We make use of the observed chameleon’s behavior to guide the scanning and the tracking controller design procedures, the
way they are combined together and their tuning.
Finally, simulative and experimental validation of the approach on a robotic chameleon head composed of two independent Pan-Tilt
cameras is presented.
相似文献
Ehud RivlinEmail: |
77.
The feasibility of power flattening while maintaining a nearly constant keff over the core life is assessed for the Encapsulated Nuclear Heat Source (ENHS). A couple of approaches are considered — using different fuel dimensions and using different enrichment levels across the core. Three new cores with flattened power distribution are successfully designed: Design-I uses different fuel rod diameters but uniform fuel composition; Design-II uses different fuel enrichment in the radial direction but uniform fuel rod dimensions; Design-III is similar to Design-II but uses enrichment splitting also in the axial direction. Relative to the reference ENHS core, the BOL peak-to-average channel power ratio is reduced from 1.50 to 1.15, 1.22 and 1.15 and the average discharge burnup increases by 8.5%, 27.9% and 41.2% for, respectively, Design-I, -II and -III. The corresponding burnup reactivity swings over 20 years of full power operation are 0.37%, 0.52% and 0.60% relative to 0.22% of the reference design. Design-II and -III have a negative coolant expansion reactivity defect while in the reference design this defect is positive. The radial power flattening increases the reactivity worth of the peripheral absorbers of the three new designs while the central absorber reactivity worth is reduced but their sum is nearly maintained. The newly designed cores have slightly more positive coolant void reactivity worth than the reference ENHS core. 相似文献
78.
The morphology of fracture surfaces of unidirectional carbon fibre reinforced plastic composites has been studied to categorize the fractographic characteristics for several types of loading. Specimens were tested in compression and in tension, both in the axial and the transverse direction, in bending and in interlaminar shear. The influence of prior exposure to moisture and to elevated temperature on the fracture morphology of specimens tested at elevated temperature has also been studied. Optical and scanning electron microscopy were used for the fracture surface analyses. Fractographic features characteristic of each mode of stressing and directionality of specimen were identified. 相似文献
79.
Metaquery (metapattern) is a data mining tool which is useful for learning rules involving more than one relation in the database. The notion of a metaquery has been proposed as a template or a second-order proposition in a language that describes the type of pattern to be discovered. This tool has already been successfully applied to several real-world applications.In this paper we advance the state of the art in metaquery research in several ways. First, we argue that the notion of a support value for metaqueries, where a support value is intuitively some indication to the relevance of the rules to be discovered, is not adequately defined in the literature, and, hence, propose our own definition. Second, we analyze some of the related computational problems, classify them as NP-hard and point out some tractable cases. Third, we propose some efficient algorithms for computing support and present preliminary experimental results that indicate the usefulness of our algorithms. 相似文献
80.
Yuval?Bitan Joachim?MeyerEmail author David?Shinar Ehud?Zmora 《Cognition, Technology & Work》2004,6(4):239-246
Neonatal intensive care units (NICUs), like other intensive care units, are intended to provide immediate responses to any change in the patients condition. Patient-monitoring alarms and alarms from other medical equipment are very common in these units, and most alarms have no clinical significance. This study addresses the question of how alarms affect nurses actions by measuring the occurrence of alarms from different causes in a NICU, recording the nurses reactions, and analyzing the relationship between the alarms and the actions. The results show that nurses often do not respond directly to alarms, but, rather, use them as additional sources of information in their ongoing flow of actions. The probabilities for their responding to an alarm depend on the causes of the alarm, its duration, and the characteristics of the patient. These findings support the view that experienced nurses dynamically adjust their activities according to the information they receive from alarm systems and other sources, and that they combine their reactive actions with the periodic performance of routine tasks. 相似文献