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121.
One of the drastically growing and emerging research areas used in most information technology industries is Bigdata analytics. Bigdata is created from social websites like Facebook, WhatsApp, Twitter, etc. Opinions about products, persons, initiatives, political issues, research achievements, and entertainment are discussed on social websites. The unique data analytics method cannot be applied to various social websites since the data formats are different. Several approaches, techniques, and tools have been used for big data analytics, opinion mining, or sentiment analysis, but the accuracy is yet to be improved. The proposed work is motivated to do sentiment analysis on Twitter data for cloth products using Simulated Annealing incorporated with the Multiclass Support Vector Machine (SA-MSVM) approach. SA-MSVM is a hybrid heuristic approach for selecting and classifying text-based sentimental words following the Natural Language Processing (NLP) process applied on tweets extracted from the Twitter dataset. A simulated annealing algorithm searches for relevant features and selects and identifies sentimental terms that customers criticize. SA-MSVM is implemented, experimented with MATLAB, and the results are verified. The results concluded that SA-MSVM has more potential in sentiment analysis and classification than the existing Support Vector Machine (SVM) approach. SA-MSVM has obtained 96.34% accuracy in classifying the product review compared with the existing systems.  相似文献   
122.
To achieve high performance distributed data access and computing in Grid environment, monitoring of resource and network performance is vital. Our proposed Grid network monitoring architecture is modeled by the Grid scheduler. The proposed Grid network monitoring retrieves network metrics using sensors as network monitoring tools. The mobile agents are migrated to start the sensors to measure the network metrics in all Grid Resources from the Resource Broker. The raw data provided by the monitoring tools is used to produce a high level view of the Grid through the set of internal cost functions. The network cost function is formed by combining various network metrics such as bandwidth, Round Trip Time, jitter and packet loss to measure the network performance. This paper presents the Grid Resource Brokering strategy which analyzes the network metrics along with the resource metrics for the selection of the Grid resource to submit the job and the proposed approach is integrated with CARE Resource Broker (CRB) for job submission. The experimental results are evident for the minimization of job completion time for the submitted job. The simulation results also prove that the more number of jobs are completed with the proposed strategy which influences the better utilization of the Grid resources.  相似文献   
123.
The morphology and ultrastructure of the Malpighian tubules of Dolycoris baccarum were analyzed by scanning (SEM) and transmission (TEM) electron microscopy in order to determine their functional organization. The Malpighian tubules are compared with similar structures of other insects based on cell structure and functional organization. The Malpighian tubules of D. baccarum extend from the midgut–hindgut region of the digestive tract. The Malpighian tubules are divided into two regions: the proximal segment is short and flattened and the distal segment is long, stringy in shape and free in hemolymph. The tubules are generally long and narrow. There is a large number of trachea around the tubules. They consist of a single layer of epithelial cells. It is observed in the TEM observation that the epithelial cells have numerous microvilli at the apical side of the cells. At the basal side of the cells, there is a great number of membrane foldings and mitochondria among them. Besides some spherites, mitochondria, lysosome‐like bodies, and large or small granules can be distinguished in the cells. With this study, we aimed to demonstrate the ultrastructure of the Malpighian tubules of D. baccarum and differences or similarities with other species.  相似文献   
124.
The autocatalytic (electroless) deposition of Ni-P based alloys is a well-known commercial process that has found numerous applications because of their excellent anticorrosive, wear, magnetic, solderable properties, etc. It is a barrier coating, protecting the substrate by sealing it off from the corrosive environments, rather than by sacrificial action. The corrosion resistance varies with the phosphorus content of the deposit: relatively high for a high-phosphorus electroless nickel deposit but low for a low-phosphorus electroless nickel deposit. In the present investigation ternary Ni-W-P alloy films were prepared using alkaline citrate-based bath. Quaternary Ni-W-Cu-P films were deposited by the addition of 3 mM copper ions in ternary Ni-W-P bath. X-ray diffraction (XRD) studies indicated that all the deposits were nanocrystalline, i.e. 1.2, 2.1 and 6.0 nm, respectively, for binary, ternary and quaternary alloys. Corrosion resistance of the films was evaluated in 3.5% sodium chloride solution in non-deaerated and deaerated conditions by potentiodynamic polarization and electrochemical impedance (EIS) methods. Lower corrosion current density values were obtained for the coatings tested in deaerated condition. EIS studies showed that higher charge transfer resistance values were obtained for binary Ni-P coatings compared to ternary or quaternary coatings. For all the coatings a gradual increase in the anodic current density had been observed beyond 740 mV. In deaerated condition all the reported coatings exhibited a narrow passive region and all the values of Ep, Etp and ipass were very close showing no major changes in the electrochemical behavior. In the non-deaerated conditions no passivation behavior had been observed for all these coatings.  相似文献   
125.
The synthetic applications of aroyl- and nitro-substituted D-A cyclopropanes probed in the authors’ laboratory are reviewed. These cyclopropanes, though looking similar, exhibit markedly different reactivity patterns. Lewis acid-mediated transformations of these cyclopropanes (in the presence or absence of a reaction partner) afford a variety of carbocycles and heterocycles. Mechanistic aspects of the reactions are discussed for clear understanding of the transformations.  相似文献   
126.
In this study, an isolated three-level DC-DC converter is proposed for high power and high conversion ratio applications such as fuel cells. The proposed system consists of a single phase three-level inverter, a medium frequency transformer and a diode rectifier unit. In the proposed system, a DC supply voltage is converted to a medium frequency AC voltage via a three-level inverter instead of the conventional two-level inverter. Since the three-level inverter generates an AC waveform with multiple steps, lower voltage harmonics and lower EMI levels than conventional two-level inverter are achieved. Thus, the three-level inverter provides higher efficiency value. The medium frequency transformer enables high voltage conversion ratio and provides galvanic isolation as well. The output voltage of the medium frequency transformer is converted to the DC voltage and thus the DC-DC conversion is achieved. According to simulation and experimental results, it is seen that the proposed DC-DC converter structure provides higher power density and higher efficiency values than conventional system.  相似文献   
127.
In this study, montmorillonite (MMT) clay was modified with different acids to be used as support material. The modified MMT clay was used to obtain hydrogen in the hydrolysis reactions of NaBH4 (NaBH4-HR) as a support material for the Co–B and Co–Fe–B catalyst. During the activation of MMT clay, the effects of different acids, phosphoric acid (H3PO4) concentration, and impregnation time with H3PO4 were investigated. During the hydrogen generation from the NaBH4-HR, effects of Co loading, Fe loading, NaBH4 concentration, temperature and, catalyst durability were investigated. The maximum HGRs for MMT-H3PO4–CoB and MMT-H3PO4–Co–Fe–B treated with 5 M H3PO4 for 7 days were 1869 and 4536 mL/min/gcatalyst, respectively. The activation energies for MMT-H3PO4–CoB and MMT-H3PO4–Co–Fe–B catalyst samples were 49.5 and 38.90 kJ/mol.  相似文献   
128.
129.
Nanomedicine is an interdisciplinary approach that involves toxicology and other medicinal applications. Gold nanoparticles (AuNPs) may serve as a promising model to address the size and shape‐dependent biological response because they show good biocompatibility. This study is to prepare phytosynthesis AuNPs from ten different Cassia sp. Among them, the aqueous leaf extract of C. roxburghii produced greater efficient and stable AuNPs. The AuNPs were optimised for different physicochemical conditions. Highly stable AuNPs were synthesised at pH 7.0, 37°C, 1.0 ml of C. roxburghii leaf extract and 1.0 mM concentration of HAuCl4 with the particle size of ∼50 nm and these AuNPs were stable up to 12 months. To determine the safety profile of AuNPs in‐vivo, the nanoparticles were injected intravenously into male Wistar albino rats in varying dosages. The authors noticed no significant difference in body weights, haematological and biochemical parameters and the histopathological sections of all vital organs. Highest accumulation was seen in spleen and least in brain. The authors’ results show that the AuNPs were biocompatible and did not produce any adverse or abnormalities in‐vivo. The implications of the bioaccumulation of AuNPs need to be further studied to rule out any adverse effects on long‐term exposure.Inspec keywords: blood, nanoparticles, cellular biophysics, pH, nanomedicine, particle size, nanofabrication, gold, biomedical materialsOther keywords: in‐vivo biocompatibility evaluation, phytogenic gold nanoparticles, phytosynthesis AuNPs, physicochemical conditions, Wistar albino male rats, nanomedicine, Cassia sp., aqueous leaf extract, C. roxburghii leaf extract, particle size, bioaccumulation, temperature 37.0 degC, Au  相似文献   
130.
Broadcasting is one of the major emergency services of Vehicular ad hoc network, since the number of vehicles increases every day. Because of the high density of the vehicles, it is necessary to broadcast emergency messages to all the vehicles to avoid traffic jam and vehicle accidents. Reliable broadcasting of messages in self-organizing Ad hoc networks is a promising research field. In this paper a cluster based emergency message broadcasting algorithm is proposed. In this regard we have proposed cluster based architecture for emergency message dissemination and collision avoidance in VANET. In this paper, first the formation of cluster is done in such a way that it avoids any kind of collision. Once cluster head is selected it takes the responsibility of intra cluster management to avoid interference between the clusters. To increase the reliability during emergency message dissemination two MAC layer broadcasts protocol is used. This assures that message is delivered on time without any hazards. The proposed model is simulated for DSDV, AODV, and DSR protocols with the standards 802.11 and 802.11p in SHWM, Manhattan and freeway mobility models.  相似文献   
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