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21.
Wireless Body Area Sensor Networks (WBASN) are an emerging technology enabling the design of natural human–computer interfaces (HCI). Automatic recognition of human motion, gestures, and activities is studied in several contexts. For example, mobile computing technology is being considered as a replacement of traditional input systems. Moreover, body posture and activity monitoring can be used for entertainment and health-care applications. However, until now, little work has been done to develop flexible and efficient WBASN solutions suitable for a wide range of applications. Their requirements pose new challenges for sensor network designs, such as optimizing traditional solutions for use as environmental monitoring-like applications and developing on-the-field stress tests. In this paper, we demonstrate the flexibility of a custom-designed WBASN called WiMoCA with respect to a wide range of posture and activity recognition applications by means of practical implementation and on-the-field testing. Nodes of the network mounted on different parts of the human body exploit tri-axial accelerometers to detect its movements. The advanced digital Micro-electro-mechanical system (MEMS) based inertial sensor has been chosen for WiMoCA because it demonstrated high flexibility of use in many different situations, providing the chance to exploit both static and dynamic acceleration components for different purposes. Furthermore, the sensibility and accuracy of the sensing element is perfectly adequate for monitoring human movement, while keeping cost low and size compact, thus meeting our requirements. We implemented three types of applications, stressing the WBASN in many aspects. In fact, they are characterized by different requirements in terms of accuracy, timeliness, and computation distributed on sensing nodes. For each application, we describe its implementation, and we discuss results about performance and power consumption.
Andrea AcquavivaEmail:
  相似文献   
22.
Reptiles represent an interesting animal model to investigate the influence of temperature on molecular circadian clocks. The ruin lizard Podarcis sicula lives in a continental climate and it is subjected to wide range of environmental temperatures during the course of the year. As consequence, ruin lizard daily activity pattern includes either the hibernation or periods of inactivity determined by hypothermia. Here we showed the rhythmic expression of two clock genes, lPer2 and lClock, in the liver of active lizards exposed to summer photo-thermoperiodic conditions. Interestingly, the exposition of lizards to hypothermic conditions, typical of winter season, induced a strong dampening of clock genes mRNA rhythmicity with a coincident decrease of levels. We also examined the qualitative and quantitative distribution of lPER2 and lCLOCK protein in different cellular compartments during the 24-h cycle. In the liver of active lizards both proteins showed a rhythmic expression profile in all cellular compartments. After 3 days at 6 degrees C, some temporal fluctuations of the lCLOCK and lPER2 are still detectable, although, with some marked modifications in respect to the values detected in the liver of active lizards. Besides demonstrating the influence of low temperature on the lizard liver circadian oscillators, present results could provide new essential information for comparative studies on the influence of temperature on the circadian system across vertebrate classes.  相似文献   
23.
This article examines the use of output-based aid and payment for environmental services to reduce water pollution in Brazil. Two nationwide initiatives are reviewed. First, the output-based aid concept of the River Basin Clean-up Programme (PRODES) to tackle the problem of sanitation deficit in urban areas is presented. Second, the payment for environmental services scheme supported by Brazil’s National Water Agency (ANA) through the Water Producer Programme to promote water conservation on rural properties is discussed. Both programmes are evaluated not only as financing mechanisms for water conservation but also as strategies for implementing Brazil’s water policy.  相似文献   
24.
In this paper we investigate on the existence of the stabilizing solution of the algebraic Riccati equation (ARE) related to the filtering problem with a prescribed attenuation level γ. It is well known that such a solution exists and is positive definite for γ larger than a certain γF and it does not exist for γ smaller than a certain γ0. We consider the intermediate case γ(γ0F] and show that in this interval the stabilizing solution does exist, except for a finite number of values of γ. We show how the solution of the ARE may be employed to obtain a minimum-phase J-spectral factor of the J-spectrum associated with the filtering problem.  相似文献   
25.
The aim of this study was to show that abundant and inexpensive plant oils can be biotransformed to increase biological activity (antioxidant, antimicrobial and cytotoxicity) through hydrolysis reaction catalysed by lipases. We tested homemade and commercial lipases through the biotransformation of nine different plant oils in forty different combinations. First, the chemical composition of the samples was investigated. Thereafter, biological tests were conducted to assess the antioxidant and antimicrobial activity of the sampled biotransformation products, as well as analyzed their influence on the viability of healthy and cancer cells. Summarising, sunflower, corn and olive oils modified by orange waste-obtained lipases presented the most promising results, reaching up to 90% of antioxidant activity increase and significant growth inhibition of bacteria colonies belonging to genera Escherichia, Listeria, Staphylococcus, Pseudomonas and Salmonella. In addition, those compounds affected human oral squamous carcinoma cells. The bioconversion of plant oils through lipases improves their biological properties and might be an option for biotechnological application.  相似文献   
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Research on performance management (PM) of networks and radical innovation has largely developed along two isolated paths. On the one hand, a growing body of knowledge addresses the use of performance management systems in the context of networks (notably for production and incremental innovation). On the other hand, radical innovation scholars have shown how innovation initiatives that are more uncertain demand the use of new approaches (e.g., new project management routines or different evaluative tools for portfolios). Some scholars even suggest that traditional PM may suppress radical innovation. Our study takes a different approach. It aims to bridge radical innovation and network performance management through a systematic review of the literature. Here, we adopt a hybrid approach that combines bibliometrics with content analysis. Whereas the literature often separates the issues of network performance management and radical innovation, our contribution expands the theory of network management and radical innovation by developing a conceptual framework based on these concepts, thus combining them. We also offer suggestions for further research on this approach. Our framework suggests that overall, the performance management of radical innovation networks presents different features (e.g., recursive rather than linear) and constructs (e.g., openness and unintended performance) from those of innovation network management.  相似文献   
28.
The objective of our study was to investigate the associative effects of feeding Ca salts of palm fatty acids (FA) and corn grain-processing method on production, nutrient digestibility, energy balance, and carryover effects of early-lactation dairy cows grazing a tropical pasture. Treatment diets were offered from 3 to 16 wk postpartum (treatment period), in which all cows grazed elephant grass (Pennisetum purpureum L. Cameroon) and treatments were added to a concentrate supplement. Treatments were flint corn grain-processing method either as fine ground (FGC) or steam-flaked (SFC) associated with Ca salts of palm FA supplementation either not supplemented or supplemented (CSPO). From 17 to 40 wk postpartum (carryover period) all cows received a common diet fed as total mixed ration. During the treatment period, a tendency for an interaction between CSPO and corn grain-processing method were observed for milk yield, milk fat yield, and energy-corrected milk (ECM), as CSPO caused them to increased to a greater extent in the FGC diet compared with the SFC diet. Furthermore, a tendency for an interaction between CSPO and corn grain-processing method was observed for body weight change, because CSPO increased body weight loss in the FGC diet but not in the SFC diet. The CSPO increased milk yield, milk fat yield, 3.5% fat-corrected milk, ECM, and cumulative milk yield compared with not supplemented. Also, CSPO increased energy intake, milk energy output, and energy partitioning toward milk, whereas reduced energy was allocated to body reserves. The SFC increased milk yield, ECM, milk protein yield, milk casein yield, and cumulative milk yield, and decreased milk urea N compared with FGC. The SFC compared with FGC also increased body condition score and body weight change, and increased energy partitioning toward body reserves. During the carryover period, an interaction between CSPO and corn grain-processing method was observed for milk yield, which occurred because CSPO maintained higher milk yield in the FGC diet but not in the SFC diet. Therefore, in the carryover period, the additive effect between SFC and CSPO that occurred in the treatment period was not maintained throughout the carryover period. However, CSPO increased yields of milk fat, protein, casein as well as fat-corrected milk and ECM. In conclusion, corn grain-processing method interacts with CSPO supplementation on production responses and carryover effects of grazing cows. When CSPO was fed in the FGC diet, milk production increased to a greater extent than when fed in the SFC diet, but also caused greater mobilization of reserves at early lactation. This suggests an interaction between fat supplementation and corn grain-processing method on energy partitioning of dairy cows. Also, both supplementation with CSPO and SFC were effective strategies to increase energy intake and yields of milk and milk solids. The carryover effect on milk production was greater for CSPO supplementation than corn grain-processing method, whereas feeding SFC diets had lower mobilization of reserves and less body weight and body condition score variation throughout lactation.  相似文献   
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30.
A highly hydrophobic silica mesostructure was synthesized by a modification on the conventional co-condensation procedure that involved the partial substitution of hexadecytltrimethylammonium, used as mesostructure directing agent, by hexadecyltrimethoxysilane. That modification allowed the production of a highly ordered hexagonal silica mesostructure with the mesopores partially filled with high amounts of hexadecyl chains, covalently bonded to inorganic framework. After extracting the reminiscent template molecules, ibuprofen was loaded into the mesostructure in order to evaluate its drug release properties. The drug loading amount (21 wt%) was comparable to the one reported for MCM-41 with grafted propylamine groups (25 wt%), indicating that C16-chains were not fully compacted occluding the pores. A slow ibuprofen release was observed in simulated body fluid (pH 7.2) by a process controlled by an anomalous transport with contribution of diffusional and relaxational components, according to the Korsmeyer-Peppas kinetics model. That hydrophobic mesostructure produced has the potential of being use as a carrier for low water soluble drugs with an extended delivery effect, but without the disadvantages of co-releasing toxic surfactant molecules or the need of non-toxic specific templates to be prepared.  相似文献   
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