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81.
Web mining is the process of extracting useful information from Web resources. Handling outliers is one of the primary challenges of present Web mining techniques. The complex nature of the Web, by virtue of both data and users, makes it very difficult to mine the information and convert to knowledge base with little outlier values. In this paper, a framework for reducing outliers in regression analysis with the help of ordered weighted operators (OWA) as a multicriteria decision‐making problem is being formulated. First, a regression problem with a real‐time Web data set will be formulated followed by solving the same with the help of a variant of OWA operators. Results, thus obtained are able to prove that outliers can be reduced significantly with the help of proposed approach.  相似文献   
82.
A commonly held view is that emotional stimuli are processed independently of awareness. Here, the authors parametrically varied the duration of a fearful face target stimulus that was backward masked by a neutral face. The authors evaluated awareness by characterizing behavioral performance using receiver operating characteristic curves from signal detection theory. Their main finding was that no universal objective awareness threshold exists for fear perception. Although several subjects displayed a behavioral pattern consistent with previous reports (i.e., targets masked at 33 ms), a considerable percentage of their subjects (64%) were capable of reliably detecting 33-ms targets. Their findings suggest that considerable information is available even in briefly presented stimuli (possibly as short as 17 ms) to support masked fear detection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
Cancer is the second leading cause of death throughout the world. Nature-inspired anticancer agents (NAAs) that are a gift of nature to humanity have been extensively utilized in the alleviation/prevention of the disease due to their numerous pharmacological activities. While the oral route is an ideal and common way of drug administration, the application of NAAs through the oral pathway has been extremely limited owing to their inherent features, e.g., poor solubility, gastrointestinal (GI) instability, and low bioavailability. With the development of nano-driven encapsulation strategies, polymeric vehicles, especially those with natural origins, have demonstrated a potent platform, which can professionally shield versatile NAAs against GI barricades and safely deliver them to the site of action. In this review, the predicament of orally delivering NAAs and the encapsulation strategy solutions based on biopolymer matrices are summarized. Proof-of-concept in vitro/in vivo results are also discussed for oral delivery of these agents by various biopolymer vehicles, which can be found so far from the literature. Last but not the least, the challenges and new opportunities in the field are highlighted.  相似文献   
84.
Passive, stand-alone, direct methanol fuel cells require a pressure management system that releases CO2 produced in the anode chamber. However, this must be done without allowing the methanol fuel to escape. In this paper, two siloxane membranes are investigated and shown to selectively vent CO2 from the anode chamber. The addition of hydrophobic additives, 1,6-divinylperfluorohexane and 1,9-decadiene, improved the selectivity of the siloxane membranes. The best performing CO2 vent was obtained with 50:50 wt% poly(1-trimethyl silyl propyne) and 1,6-divinylperfluorohexane.  相似文献   
85.
Estuaries are among the most invaded ecosystems on the planet. Such invasions have led in part, to the formation of a massive $1 billion restoration effort in California's Sacramento–San Joaquin River Delta. However, invasions of weeds into riparian, floodplain, and aquatic habitats threaten the success of restoration efforts within the watershed and jeopardize economic activities. The doctrine of early detection and rapid response to invasions has been adopted by land and water resource managers, and remote sensing is the logical tool of choice for identification and detection. However meteorological, physical, and biological heterogeneity in this large system present unique challenges to successfully detecting invasive weeds. We present three hyperspectral case studies which illustrate the challenges, and potential solutions, to mapping invasive weeds in wetland systems: 1) Perennial pepperweed was mapped over one portion of the Delta using a logistic regression model to predict weed occurrence. 2) Water hyacinth and 3) submerged aquatic vegetation (SAV), primarily composed of Brazilian waterweed, were mapped over the entire Delta using a binary decision tree that incorporated spectral mixture analysis (SMA), spectral angle mapping (SAM), band indexes, and continuum removal products. Perennial pepperweed detection was moderately successful; phenological stage influenced detection rates. Water hyacinth was mapped with modest accuracies, and SAV was mapped with high accuracies. Perennial pepperweed and water hyacinth both exhibited significant spectral variation related to plant phenology. Such variation must be accounted for in order to optimally map these species, and this was done for the water hyacinth case study. Submerged aquatic vegetation was not mapped to the species level due to complex non-linear mixing problems between the water column and its constituents, which was beyond the scope of the current study. We discuss our study in the context of providing guidelines for future remote sensing studies of aquatic systems.  相似文献   
86.
This work is a systematic experimental and theoretical study of the in-plane dielectric functions of 2D gallium and indium films consisting of two or three atomic metal layers confined between silicon carbide and graphene with a corresponding bonding gradient from covalent to metallic to van der Waals type. k-space resolved free electron and bound electron contributions to the optical response are identified, with the latter pointing towards the existence of thickness dependent quantum confinement phenomena. The resonance energies in the dielectric functions and the observed epsilon near-zero behavior in the near infrared to visible spectral range, are dependent on the number of atomic metal layers and properties of the metal involved. A model-based spectroscopic ellipsometry approach is used to estimate the number of atomic metal layers, providing a convenient route over expensive invasive characterization techniques. A strong thickness and metal choice dependence of the light–matter interaction makes these half van der Waals 2D polar metals attractive for quantum engineered metal films, tunable (quantum-)plasmonics and nano-photonics.  相似文献   
87.

With advancements in technology, size and speed have been the important facet in VLSI interconnects. The channel length of the device reduces to tens of nanometers, as the technology is transferring to the deep submicron level. This leads to the requirement of long interconnects in VLSI chips. Interconnects are known as the basic building block that can vary from size to size. They provide a connection between two or more blocks and have scaling problems that an IC designer faces while designing. As scaling increases, the impact of interconnect in the VLSI circuits became even more important. It controls all the important electrical characteristics on the chip. With scale-down technology, interconnects not only become closer with each other but their dimensions also change which can directly impact the circuit parameters. Certain RC models have already been defined to control these parameters but in this paper, authors have proposed a new improved Elmore delay estimation model (RC) to reduce delay and power consumption in interconnect circuits. An optimized Elmore delay calculation was performed for uniform and non-uniform wires to reduce the time constant of the interconnect circuits. Further, the proposed model is estimated and verified theoretically. A new improved RC model is compared to the designed π-model that shows remarkable results. We also observed the linear relationship of power consumption and delay for both the RC models and found that in π-model, upon decreasing the length of wire the power first increases then decreases but in the proposed model, the power first increases then remain constant and then further increases upon increasing the length of wire. Our proposed model shows the remarkable values as the average percentage improvement of power is 75.167% and delay as 74.714% is achieved using a uniform distribution.

  相似文献   
88.
In this work, "isobutrin", an ecofriendly sensitizer that is extracted from Butea monosperma (commonly known as "Flame of the Forest") flowers, is introduced. It is a bright yellow pigment belonging to the chalcone class and is examined as a sensitizer for optoelectronic applications. It is observed that chelation of this dye with Ti ions results into a strong dye-TiO(2) charge transfer (DTCT) band in the visible region. This Ti-Isobutrin chelate is stable, irreversible and its formation is studied using Benesi-Hildebrand plot. The locations of HOMO-LUMO states of the Ti-isobutrin chelate and the corresponding band alignment with TiO(2) are obtained. Also, a thermal stability test revealed that isobutrin is stable above 100 °C.  相似文献   
89.
BACKGROUND: Fresh vegetable produce is abundant during the winter season in Punjab. It is an important source of vitamins and minerals in the Punjabi diet, but the availability of ascorbic acid and beta-carotene from the vegetables is altered to varying degrees when they are subjected to traditional household processing methods. OBJECTIVE: To determine the importance of traditional cooked vegetable dishes as sources of ascorbic acid and beta-carotene among urban and rural families during the winter. METHODS: Information about vegetable consumption, storage, and cooking practices was collected from 60 families, 30 each from urban and rural areas of Ludhiana District, Punjab, India. Samples of the common cooked vegetable dishes were prepared in the laboratory by methods ascertained from the survey and analyzed for ascorbic acid and beta-carotene. RESULTS: The average total daily per capita consumption of vegetables by urban and rural families was 411.7 and 365.9 g, respectively. Cooked vegetable dishes provided 68.7% of the total vegetable intake for urban families and 85.0% for rural families. On average, the edible portion constituted 78.9% of the weight of the vegetables. Ten cooked vegetable dishes that were most frequently consumed by the families (mustard saag, potato-spinach, potato-fenugreek, potato-brinjal, potato-cauliflower, potato-capsicum, potato-carrots, potato-beans, potato-peas, and cabbage-peas) were selected for preparation in the laboratory and nutritional analysis. The average concentrations of ascorbic acid and beta-carotene in the cooked vegetable dishes were 46.0 mg/100 g and 794.2 microg/100 g fresh weight, respectively. The percentage losses of ascorbic acid and beta-carotene during preparation and cooking were 26.1% and 25.9%, respectively. CONCLUSIONS: For adult Indian men and women, the recommended dietary allowance of ascorbic acid is 40 mg, and that of beta-carotene is 2,400 microg. Cooked vegetable dishes provided 269.9% and 77.5% of the recommended dietary allowances of ascorbic acid and beta-carotene, respectively, indicating that these dishes are good sources of these nutrients in the diets of both urban and rural families during the winter season.  相似文献   
90.
Multimedia Tools and Applications - In the present work, a hybrid hierarchical framework for classification of breast density using digitized film screen mammograms has been proposed. For designing...  相似文献   
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