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141.
Energy-efficient smart retail system design is a challenging research area. In this paper, we propose an automated retail system using a femtolet-based fog network. A femtolet is an indoor base station providing computation and storage. Femtolets in our system work as indoor base stations and maintain databases of the products located in their respective coverage areas. The femtolets switch to active or idle mode according to the user's presence in its coverage. A smart trolley is proposed for our retailing system, which guides the user to the particular product type selected by the user. The user, after entering the shopping mall, carries the smart trolley. The customer selects and purchases products using this trolley. On the basis of product purchasing, the respective databases maintained inside the femtolets are updated. An Android application for the proposed retailing is developed. We compare the power consumption and delay of the proposed retail system with the existing retail system. Simulation analyses illustrate that the proposed approach reduces power by approximately 89% and 94%, respectively, in comparison to the local cloud server–based and remote cloud server–based retail systems. Thus, we refer to the proposed system as a green retail system. The performance of the proposed system through experimental analysis is also evaluated.  相似文献   
142.
In this Article, we describe a microfluidic enzyme-linked immunosorbent assay (ELISA) method whose sensitivity can be substantially enhanced through preconcentration of the target analyte around a semipermeable membrane. The reported preconcentration has been accomplished in our current work via electrokinetic means allowing a significant increase in the amount of captured analyte relative to nonspecific binding in the trapping/detection zone. Upon introduction of an enzyme substrate into this region, the rate of generation of the ELISA reaction product (resorufin) was observed to increase by over a factor of 200 for the sample and 2 for the corresponding blank compared to similar assays without analyte trapping. Interestingly, in spite of nonuniformities in the amount of captured analyte along the surface of our analysis channel, the measured fluorescence signal in the preconcentration zone increased linearly with time over an enzyme reaction period of 30 min and at a rate that was proportional to the analyte concentration in the bulk sample. In our current study, the reported technique has been shown to reduce the smallest detectable concentration of the tumor marker CA 19-9 and Blue Tongue Viral antibody by over 2 orders of magnitude compared to immunoassays without analyte preconcentration. When compared to microwell based ELISAs, the reported microfluidic approach not only yielded a similar improvement in the smallest detectable analyte concentration but also reduced the sample consumption in the assay by a factor of 20 (5 μL versus 100 μL).  相似文献   
143.
Wireless Sensor Networks are a fast-growing class of systems. They offer many new design challenges, due to stringent requirements like tight energy budgets, low-cost components, limited processing resources, and small footprint devices. Such strict design goals call for technologies like nanometer-scale semiconductor design and low-power wireless communication to be used. But using them would also make the sensor data more vulnerable to errors, within both the sensor nodes' hardware and the wireless communication links. Assuring the reliability of the data is going to be one of the major design challenges of future sensor networks. Traditional methods for reliability cannot always be used, because they introduce overheads at different levels, from hardware complexity to amount of data transmitted. This paper presents a new method that makes use of the properties of sensor data to enable reliable data collection. The approach consists of creating predictive models based on the temporal correlation in the data and using them for real-time error correction. This method handles multiple sources of errors together without imposing additional complexity or resource overhead at the sensor nodes. We demonstrate the ability to correct transient errors arising in sensor node hardware and wireless communication channels through simulation results on real sensor data.  相似文献   
144.
Hati  Sourav  Dey  Prasanjit  De  Debashis 《Microsystem Technologies》2019,25(5):1599-1612

The rapid growth of new technologies resulted in a new city model, known as the famous “Smart City”. The main aim in this paper is to create a paradigm for building an energy efficient smart city. Wireless local area network (WLAN) controller that will be used by the city will be constructed in such a manner that when there will be no request from any node to the access point (AP), the AP will be send from active mode to sleep mode. In Qualnet7.2, with the help of three types of energy model generic, mica z and mica motes the energy consumption in three modes transmit, receive and sleep mode is analysed, where it is seen that energy consumption in sleep mode is much less than in any other modes. In this paper, we propose an algorithm where it is shown that the energy consumption in sleep mode is less than in any other modes.

  相似文献   
145.
Phototherapy represents an attractive route for treating a range of challenging dermatological diseases. Existing skin phototherapy modalities rely on direct UV illumination, although with limited efficacy in addressing disorders of deeper tissue and with requirements for specialized illumination equipment and masks to shield unaffected regions of the skin. This work introduces a skin-integrated optoelectronic device that incorporates an array of UVA (360 nm) light emitting diodes in layouts that match those of typical lesional plaques and in designs that couple to biocompatible, penetrating polymer microneedle light waveguides to provide optical access to deep skin. Monte Carlo simulations and experimental results in phantom skin suggest that these waveguides significantly enhance light delivery to deep skin, with a >4-fold increase for depths of >500 µm. In ex vivo human skin, the devices show reduced measures of phototoxicity compared to direct illumination and enhanced modulation of gene expression relevant to sclerosing skin diseases. These systems are also compatible with design principles in soft, skin-compatible electronics and battery-powered wireless operation. Collectively, the favorable mechanical and light delivery properties of these devices expand possibilities in targeting of deep skin lesions beyond those attainable with clinical-standard UV light therapy approaches.  相似文献   
146.
Due to rapid development of Web 2.0 Technology social networking have gained explosive growth. This paper proposes a comparatively new approach to build a trust based social network named Trust Based Friend Net (TBFN) for smartphone users. In TBFN, call log and sms log extracted from user’s smartphone are outsourced into the corresponding social network cloud. Analyzing those real datasets the cloud service provider determines trust values of different direct and indirect friends of smartphone users. Global analysis of everyone’s data results in forming a trusted global social network that is free from fake profiles and that minimizes unscrupulous activities.  相似文献   
147.
High-throughput gene expression technologies such as microarrays have been utilized in a variety of scientific applications. In this article, we develop multivariate techniques for visualizing gene regulatory networks using independent components analysis (ICA) techniques. A desirable feature of the ICA method is that it approximates a biological model for the gene expression. The methods are outlined and illustrated with application to yeast gene expression data.  相似文献   
148.
A unified decomposition scheme for two very important cyclic nitramines used as primary explosives – RDX and HMX – has been constructed using ab initio Density Functional Theory (DFT) calculations. Molecular parameters such as vibrational frequencies and moments of inertia corresponding to the computed potential energy profile of unimolecular decomposition of these nitramines were then used to obtain the thermochemistry of all identified species and reaction rate constants of each individual channel. These primary decomposition reactions were then combined with: (i) important secondary reactions of the key reactive radical intermediates, such as CH2NNO2 (Methylene Nitramine MN), CH2N, NO, NO2, OH, etc.; (ii) existing nitramie reaction networks [33]. We have developed an improved mechanism for the detailed chemistry of nitramines which can be applied to combustion and detonation phenomena of this class of energetic materials. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
149.
Copper(I) thiocyanate (CuSCN) is rising to prominence as a hole‐transporting semiconductor in various opto/electronic applications. Its unique combination of good hole mobility, high optical transparency, and solution‐processability renders it a promising hole‐transport layer for solar cells and p‐type channel in thin‐film transistors. CuSCN is typically deposited from sulfide‐based solutions with diethyl sulfide (DES) being the most widely used. However, little is known regarding the effects of DES on CuSCN films despite the fact that DES can coordinate with Cu(I) and result in a different coordination polymer having a distinct crystal structure when fully coordinated. Herein, the coordination of DES in CuSCN films is thoroughly investigated with a suite of characterization techniques as well as density functional theory. This study reveals that DES directly affects the microstructure of CuSCN by stabilizing the polar crystalline surfaces via the formation of strong coordination bonds. Furthermore, a simple antisolvent treatment is demonstrated to be effective at modifying the microstructure and morphology of CuSCN films. The treatment with tetrahydrofuran or acetone leads to uniform films consisting of CuSCN crystallites with high crystallinity and their surfaces passivated by DES molecules, resulting in an increase in the hole mobility from 0.01 to 0.05 cm2 V?1 s?1.  相似文献   
150.
Fermentation and drying process in tea production are two important processes which play a crucial role in producing good quality tea. Tea colour and flavour are formed in the fermentation and enzyme reactions are terminated and moisture contents are reduced from the leaf particles in the drying process. Ambient temperature and relative humidity (RH) are two major factors for the fermentation process. Firing temperature of dryer is also responsible for the final quality of tea. This paper presents an instrument comprising of sensor network to monitor temperature and RH for the fermentation process and firing temperature of the dryer. For dryer temperature monitoring a thermocouple based measuring system is developed. For fermentation an RH to voltage converter and temperature to voltage converter type sensor is used to develop the RH and temperature monitoring sensor node. The sensor nodes for different stages are connected in RS 485 network. Data are logged into the hard drive of a personal computer using the developed data acquisition software. The instrument will be helpful for recording these parameters and so that their influence can be determined and final quality can be improved.  相似文献   
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