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101.
Females of the inbred mouse RR strain have a limited ability to nurture their offspring, and frequently the young die during rearing. Quantitative trait locus analysis was carried out on the F2 progeny produced from a genetic cross between RR and KK, a strain of normal nurturing ability, to elucidate the putative genetic basis governing certain aspects of the inferior nurturing ability in the RR strain. One hundred and ninety-two F2 female mice were mated with C57BL/6J males. After the number of newborns was adjusted to six per dam, nurturing ability was evaluated on the basis of litter weight at days 7, 12 and 21 after parturition. The results showed that 147 of the 192 F2 dams were able to rear all six pups, although the litter weight varied considerably among litters. Significant evidence for linkage was identified on chromosome 5 near the microsatellite marker of D5Mit161 for litter weight at 12 days after parturition. The R allele (RR strain) at this locus was recessive to the K allele (KK strain), and reduced the litter weight. It is suggested that this locus is one of the heritable components that determine the inferior nurturing ability of RR mice.  相似文献   
102.
Information systems have to be consistent and secure in presence of multiple conflicting transactions. The role-based access control (RBAC) model is widely used to keep information systems consistent and secure. A role shows a job function in an enterprise and is a set of access rights (permissions). Here, a subject s is allowed to issue a method op to an object o only if an access right 〈o, op〉 is included in the roles granted to the subject s. A subject is granted one or more than one role and issues a transaction to multiple objects. The transaction is assigned with some roles of the subject which is referred to as purpose. Even if every access request issued by every subject is authorized in the roles, illegal information flow might occur as well known confinement problem. In this paper, we define a legal information flow (LIF) relation (R1 ?I R2) among a pair of role families R1 and R2 to prevent illegal information flow. Here, an LIF relation R1 ?I R2 shows that no illegal information flow occur if a transaction T1 with a role family R1 is performed prior to another transaction T2 with a role family R2. In addition, it is significant to discuss which transaction to be performed prior to another transaction if the both transactions manipulate the same object in a conflicting way. In this paper, we define a significantly precedent relation R1 ?s R2 among role families R1 and R2 which implies that the role family R2 is more significant than R1. Suppose a pair of transactions T1 and T2 with role families R1 and R2 issue conflicting methods op1 and op2, respectively, to an object o. If R1 ?s R2, op2 is performed on the object o prior to op1. The more significant a transaction is, the more prior it is performed. We discuss a legal information flow (LIF) scheduler to synchronize transactions so as to prevent illegal information flow and to serialize conflicting methods from multiple transactions in terms of significancy and information flow relation of roles families. We evaluate the LIF scheduler in terms of how much illegal information flow can be prevented compared with the other scheduler.  相似文献   
103.
We investigate the topological structure of an image and the hierarchical relationship between local and global structures provided by spatial gradients at different levels of scale. The gradient field curves link stationary points of the image including a local minimum at infinity, and construct the topological structure of the image. The evolution of the topological structure with respect to scale is analysed using pseudograph representation. The hierarchical relationships among the structures at different scales are expressed as trajectories of the stationary points in the scale space, which we call stationary curves. Each toppoint of the local extremum curve generically has a specific gradient field curve, which we call the antidirectional figure-flow curve. The antidirectional figure-flow curve connects between the toppoint and another local extremum to which the toppoint is subordinate. A point at infinity can also be connected to the toppoints of local minimum curves. These hierarchical relationships among the stationary points are expressed as a tree. As an application, we present the temporal segmentation of an image sequence based on the transition of the hierarchical structure.
Atsushi ImiyaEmail:
  相似文献   
104.
The question of whether processing three-dimensional digital patterns is much more difficult than two-dimensional ones is of great interest from both theoretical and practical standpoints. Recently, owing to advances in many application areas, such as computer vision, robotics, and so forth, it has become increasingly apparent that the study of three-dimensional pattern processing is of crucial importance. Thus, the study of three-dimensional automata as a computational model of three-dimensional pattern processing has become meaningful. This article introduces a cooperating system of three-dimensional finite automata as one model of three-dimensional automata. A cooperating system of three-dimensional finite automata consists of a finite number of three-dimensional finite automata and a three-dimensional input tape where these finite automata work independently (in parallel). Those finite automata whose input heads scan the same cell of the input tape can communicate with each other, i.e., every finite automaton is allowed to know the internal states of other finite automata on the cell it is scanning at the moment. In this article, we continue the study of cooperating systems of three-dimensional finite automata, and mainly investigate hierarchies based on the number of their cooperating systems.  相似文献   
105.
We have measured the superfluid density ρ s of 4He films adsorbed on the porous material HMM-2 by a torsional oscillator. The substrate has pores of 27 Å in diameter with ordered three-dimensional connectivity. ρ s increases as T decreases, without any feature of the universal jump and the associated dissipation peak characteristic of the two-dimensional Kosterlitz–Thouless transition. We also observed resonances of the standing wave modes, from which we can estimate the sound velocity. Assuming linear dependence on (ρ s/ρ s(0))1/2 and ignoring refractions, the sound velocities are extrapolated to about 20 m/s at T=0.  相似文献   
106.
The calculation of neutron penetration through a thick shield was performed with a three-dimensional multi-layer technique using the MARS14(02) Monte Carlo code to compare with the experimental shielding data in 1998 at the ISIS spallation neutron source facility of Rutherford Appleton Laboratory. In this calculation, secondary particles from a tantalum target bombarded by 800-MeV protons were transmitted through a bulk shield of approximately 3-m-thick iron and 1-m-thick concrete. To accomplish this deep-penetration calculation, a three-dimensional multi-layer technique and energy cut-off method were used considering a spatial statistical balance. Finally, the energy spectra of neutrons behind the very thick shield could be calculated down to the thermal energy with good statistics, and the calculated results typically agree well within a factor of two with the experimental data over a broad energy range. The 12C(n,2n)11C reaction rates behind the bulk shield were also calculated, which agree with the experimental data typically within 60%. These results are quite impressive in calculation accuracy for deep-penetration problem.  相似文献   
107.
Acoustic resonance phenomena at the front and back surfaces of a plate coated with thin layers were successfully observed in the amplitude spectrum of the back surface echo. The amplitude ratio of spectra with and without layers takes its maximum and minimum values at the resonant frequencies of the front and back coatings and both frequencies can clearly be distinguished from each other. As an application, the thicknesses of the front and back coatings on a steel plate were measured simultaneously using their resonant frequencies, thus verifying the validity of the principle.  相似文献   
108.
The synthesis of a new coil–rod–coil ABA triblock copolymers comprised of regioregular poly(3-hexylthiopene) (P3HT) and poly(methyl methacrylate) (PMMA) segments has been demonstrated by the combination of quasi-living Grignard metathesis (GRIM) polymerization and living anionic polymerization based on 1,1-diphenylethylene (DPE) chemistry. The method involves simple reaction steps, an in situ introduction of DPE moieties at the α,ω-ends of P3HT and the lithiation with sec-butyl lithium (sec-BuLi) to generate a macroinitiator bearing 1,1-diphenylalkyl anions, followed by cross-over to MMA. The selective α,ω-ends di-functionalization is a key step to achieve the ABA structure. The structural homogeneity of the precursor and block copolymer has been confirmed by gel permeation chromatography (GPC), GPC-right angle laser light scattering (RALLS), and nuclear magnetic resonance (NMR). The block copolymer has been fully characterized by differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), Ultra-violet–visible (UV–vis) and photo luminescent (PL) spectroscopies, and atom force microscopy (AFM).  相似文献   
109.
We successfully developed zeolite membranes with hydrophilic character, by choosing appropriate zeolites in terms of hydrophilicity and high acid tolerance. We evaluated thus developed membranes by their pervaporation (PV) performance, dehydration from acidic organic solvent. The zeolite membranes we developed, based on merlinoite (MER), chabazite (CHA) or phillipsite (PHI), are shown to exhibit stable dehydration performance, respectively. We successfully applied the membranes to the selective removal of water in an ester condensation reaction starting from a stoichiometric mixture of a carboxylic acid and an alcohol. The availability of pervaporation-assisted ester condensation reaction was validated by various kinds of combinations of carboxylic acid and alcohols, which implies the general availability of pervaporation-assisted process intensification by zeolite membranes. This paper was presented at the 11th Korea-Japan Symposium on Catatysis held at Seoul, Korea, May 21–24, 2007.  相似文献   
110.
The effects of pre-ozonation and subsequent biological treatment on the decrease in dissolved organic carbon (DOC) and color from dyeing wastewater were investigated. Moreover, the compositions of organic compounds in raw wastewater (RW) and the respective treated waters were estimated, and microscopic observations of the mixed liquor were conducted. The amount of ozone required to remove 1 mg of DOC and the DOC removal rate brought about by pre-ozonation ranged from 6.6 to 13.2 mgO3/mgC and 12 to 15%, respectively. The total amount of DOC removed was increased by the combined use of pre-ozonation and subsequent biological treatment, and pre-ozonation did not necessarily lead to an increase in the amount of DOC removed by biological treatment. However, this combined method was effective in decreasing color and adsorbable organic halide formation potential (AOXFP). The rates of the dyestuff in RW and the respective treated waters were less than 10% of total DOC, and those of the other non-biodegradable compounds were much higher than those of the dyestuff. The morphological difference was observed in the predominant bacteria in RW with and without pre-ozonation.  相似文献   
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