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31.
Physical blends (PB) of high oleic sunflower oil and tristearin with 20 and 30% stearic acid and their interesterified (IE) products where 20 and 30% of the fatty acids are stearic acid at the sn-2 position crystallized without and with application of high intensity ultrasound (HIU). IE samples were crystallized at supercooling temperatures (ΔT) of 12, 9, 6, and 3 °C while PB were crystallized at ΔT = 12 °C. HIU induced crystallization in PB samples, but not in the IE ones. Induction in crystallization with HIU was also observed at ΔT = 6 and 3 °C for IE C18:0 20 and 30% and at ΔT = 9 °C only for the 30% samples. Smaller crystals were obtained in all sonicated samples. Melting profiles showed that HIU induced crystallization of low melting triacylglycerols (TAGs) and promoted co-crystallization of low and high melting TAGs. In general, HIU significantly changed the viscosity, G′, and G″ of the IE 20% samples except at ΔT = 12 °C. While G′ and G″ of IE 30% did not increase significantly, the viscosity increased significantly at ΔT = 9, 6, and 3 °C from 1526 ± 880 to 6818 ± 901 Pa.s at ΔT = 3 °C. The improved physical properties of the sonicated IE can make them good contenders for trans-fatty acids replacers.  相似文献   
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33.
While gait recognition is the mapping of a gait sequence to an identity known to the system, gait authentication refers to the problem of identifying whether a given gait sequence belongs to the claimed identity. A typical gait authentication system starts with a feature representation such as a gait template, then proceeds to extract its features, and a transformation is ultimately applied to obtain a discriminant feature set. Almost every authentication approach in literature favours the use of Euclidean distance as a threshold to mark the boundary between a legitimate subject and an impostor. This article proposes a method that uses the posterior probability of a Bayes' classifier in place of the Euclidean distance. The proposed framework is applied to template-based gait feature representations and is evaluated using the standard CASIA-B gait database. Our study experimentally demonstrates that the Bayesian posterior probability performs significantly better than the de facto Euclidean distance approach and the cosine distance which is established in research to be the current state of the art.   相似文献   
34.
Three synthesis routes are presented here that leads to carbon?Csilica composites. These were characterized by nitrogen physisorption, by thermogravimetric analysis and by dynamic toluene adsorption test similar to Ashrae standard I45.1. The carbon?Csilica composites possess high microporosity and mesoporosity as well as large surface areas. Furthermore, the control of the microporosity as well as pore size distribution is possible because they depend on the amount of carbon used and of the synthesis route. Following routes I and III a wide micro-mesoporous pore size (1?C32?nm) was obtained where as by route II narrow micro-mesoporous pore size (1?C4?nm) was observed. In addition, pore diameters center in the range of 1.13?C1.17?nm was observed when carbon content was 32 or 45?wt%. The dynamic adsorption of toluene was evaluated for carbon?Csilica composites obtained by three preparation routes at two different carbon contents, 32 and 45?wt% The results showed that a composite with 45?wt% carbon content and obtained via preparation route I gave the highest toluene adsorption capacity (27.6?wt% relative to carbon content). The large uptake capacity of this composite was attributed to the presence of high microporosity volume and a wide (1?C32?nm) bimodal pore system consisting of extensive mesopore channels (2?C32?nm) as well as large surface area. These capacity values of carbon?Csilica composites are by weight relative to carbon content and are competitive to, results obtained for commercial coconut activated carbon (31.1?wt%) and significantly better than a commercial alumina-carbon composite (9.5?wt%) at 0% efficiency.  相似文献   
35.
S. Shakya  C.M. Chin  G. Owusu 《Knowledge》2010,23(4):357-362
This paper describes an applied research work that looks at different ways to effectively manage resources. Particularly, it describes how revenue management techniques can be used to balance demand against capacity, and describes a system that uses different OR and AI techniques to intelligently price diverse products and services. This system can produce pricing policies for wide range of products and services regardless of the model of demand used. The system incorporates a model specification layer, which provides flexibility in defining the demand model for different products. It also incorporates an optimisation layer, which takes the specified model as an input and produces the pricing and production guidelines for the product. The system can be either used as a stand alone system or can be incorporated as a generic modelling and optimisation component within a larger revenue management system.  相似文献   
36.
This paper documents work on automating resource management in BT Retail. BT Retail manages BT’s access network and provides telecommunications services to its customers. BT Retail’s field engineers are allocated jobs via an information system known as Work Manager. In order to proactively position the engineers (i.e. resources) so as to service jobs in an optimal manner, resource managers are involved in analysing the profiles of engineers in the light of incoming jobs and ’selecting’ those profiles that will yield best quality of service and reduce operational costs. A profile is a set of attributes that define a resource’s capabilities (i.e. skills), capacity (i.e. availability), and location (i.e. area). Resource planning involves identifying an ‘optimal’ set of resource profiles. Accurate workload forecasting is sine qua non for optimal resource planning. To this end we have developed ARMS, Automated Resource Management System, a suite of components for workload forecasting and resource planning.  相似文献   
37.
The lipid components of three Cameroonian seed oils, ke tchock (Aframomum arundinaceum), njangsa (Ricinodendron heudelotii) and calabash nutmeg (Monodora myristica), have been investigated. Gas chromatography (GC)–mass spectrometry (MS) fatty acid (FA) analysis showed M. myristica seed oil to be dominated by linoleic (49.29%) and oleic (37.17%) acids; R. heudelotii was mainly linoleic (58.73%), followed by stearic (15.00%) and oleic (14.21%) acids; A. arundinaceum was predominantly oleic (65.76%) and palmitic (20.36%) acids. Electrospray ionization (ESI)-Fourier transform ion cyclotron resonance (FTICR)-MS analysis showed seven major triacylglycerol (TAG) classes for M. myristica, with C54:5, C54:4 and C54:6 dominating. R. heudelotii had eight major TAG classes with C54:8, C54:7 and C54:6 being most abundant. A. arundinaceum also had eight major TAG classes with C52:2, C54:3 and C50:2 dominating. 13C nuclear magnetic resonance (NMR) analysis of the TAGs showed that both sn-1,3 and sn-2 positions were predominantly occupied by linoleoyl and oleoyl chains. High-performance liquid chromatography (HPLC) fluorescence detector (FLD) analysis showed that M. myristica contained only α- and β-tocopherols (195.40 and 73.95 μg/g, respectively), R. heudelotii contained mainly γ-tocopherol (289.40 μg/g), and A. arundinaceum had mainly γ- and β-tocopherols (236.78 and 124.93 μg/g, respectively). GC–MS analysis of the unsaponifiable matter showed that β-sitosterol was the most abundant phytosterol in all three seed oils. The absolute amounts of 4-desmethylsterols were 196.15, 608.71 and 362.15 μg/g for M. myristica, R. heudelotii and A. arundinaceum seed oils, respectively. These compositional and structural studies provide justification for the use of all three seed oils in food products.  相似文献   
38.
Pattern Analysis and Applications - Nowadays, thermal cameras play a major role because of its temperature-based photography in many applications such as video surveillance, monitoring...  相似文献   
39.
The study aimed at biochar production from maize cob and its performance in improving water physiochemical attributes. Three feedstock masses (2, 2.5, 3 kg) were used for biochar production. Nine treatment combinations of T1L1, T1L2, T1L3, T2L1, T2L2, T2L3, T3L1, T3L2 and T3L3 in triplicate were used for biochar performance. Biochar yield of 50% was averagely achieved at slow pyrolysis conditions (300 to 600°C) and 120 min residence time. Biochar had 4.13% moisture content, 6.86% ash, 17.70% volatile matter, 71.28% fixed carbon, and a pH of 10.27. Odour, colour, and total hardness of the wastewater improved after filtration using biochar to acceptable levels for potable water use. Total hardness reduced by 51.9% in T2L2 and 44.4% in T3L2. Findings front maize cob biochar as a purification technology for domestic potable water use. There is need for maize cob biochar performance on heavy metals and when it is sandwiched with other materials.  相似文献   
40.
Pteromalus cerealellae (Ashmead) (Hymenoptera: Pteromalidae) is a generalist parasitoid of the larvae of many stored-product insects, including the cowpea seed beetle, Callosobruchus maculatus (F.) (Coleoptera: Bruchidae), which live endophytically in cowpea seeds. The role of host-related semiochemicals in the host location behavior of this parasitoid was investigated using electroantennogram (EAG) and behavioral (olfactometer) techniques. Responses of mated and unmated female P. cerealellae were tested to a variety of host-related chemical stimuli including hexane extracts of uninfested cowpea seeds, (bruchid)-infested cowpea seeds, bruchid larvae (whole body or WB), larval frass, adult female bruchids (WB), and adult male bruchids (WB). All of the tested stimuli elicited significant EAG responses in unmated and mated female P. cerealellae, with mated females exhibiting a greater EAG response than unmated females to some treatments. Results from Y-tube olfactometer bioassays demonstrated a significant response of mated female P. cerealellae to extracts of uninfested cowpea seeds, infested cowpea seeds, adult female bruchids, bruchid larvae, and larval frass, but no significant response was elicited by the extract of adult male bruchids. Pair-wise comparisons of the four most attractive stimuli (i.e. uninfested seeds, infested seeds, bruchid larvae, and larval frass) in a four-way olfactometer showed preference of mated female P. cerealellae for the extract of uninfested cowpea seeds compared to larval frass extract. No significant differences were recorded between other paired treatments. These results suggest the relative importance of volatile cues from seeds (host habitat) in mediating host location by P. cerealellae.  相似文献   
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