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This paper presents summaries of initiatives and demonstration programs developed by professional and patient care organizations to improve care at the end of life.  相似文献   
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It is usually assumed that chlorinated solvent nonaqueous-phase liquids (NAPLs) are nonwetting with respect to water-saturated porous media. The focus of this work was to examine whether this supposition is appropriate for used trichloroethylene (TCE) samples. In this work, the term "used" indicates that the sample has been employed industrially and therefore contains solutes and breakdown products related to its previous use. The data obtained in this study indicate that exposure of initially water wet quartz slides to industrially used solvents can cause a contact angle change, measured through the aqueous phase, of 100 degrees with a maximum stable contact angle of 170 degrees (indicative of strong NAPL wetting characteristics) being recorded. The work on quartz slides was complemented by the use of sandstone cores. Wettability was measured using the Amott test. Used TCE again proved able to alter the wetting properties of sandstone to neutral wetting. The complexity of the industrially used samples precluded any realistic attempt to examine the agents causing these wetting changes. The data captured in these experiments were compared with laboratory grade TCE, and some attempts were made to synthesize known mixtures in order to replicate wetting changes. These experiments resulted in contact angle changes but did not alter the overall wettability of the quartz slides or sandstone cores. Finally the work reported here also demonstrates that increasing the duration of exposure to solvent has an important impact upon measured contact angle.  相似文献   
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Abstract— The wide‐viewing freedom often requested by users of autostereoscopic displays can be delivered by spatial multiplexing of multiple views in which a sequence of images is directed into respective directions by a suitable autostereoscopic optical system. This gives rise to two important design considerations — the optical efficiency and the resolution efficiency of the device. Optical efficiency is particularly important in portable devices such as cell phones. A comparison is given between lens and barrier systems for various spatial multiplexing arrangements. Parallax‐barrier displays suffer from reduced optical efficiency as the number of views presented increases whereas throughput efficiency is independent of the number of views for lens displays. An autostereoscopic optical system is presented for the emerging class of highly efficient polarizer‐free displays. Resolution efficiency can be evaluated by investigating quantitative and subjective comparisons of resolution losses and pixel appearance in each 3‐D image. Specifically, 2.2‐in.‐diagonal 2‐D/3‐D panel performance has been assessed using Nyquist boundaries, human‐visual contrast‐sensitivity models, and autostereoscopic‐display optical output simulations. Four‐view vertical Polarization‐Activated Microlens technology with either QVGA mosaic or VGA striped pixel arrangements is a strong candidate for an optimum compromise between display brightness, viewing angle, and 3‐D pixel appearance.  相似文献   
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Risk is inherent in distributed, large-scale systems. The paper explores the challenges of risk modeling in such systems, and suggests a risk modeling approach that is responsive to the requirements of complex, distributed, large-scale systems. An example of the use of the approach in the marine transportation system is given. The paper concludes with a discussion of limitations of the approach and of future work  相似文献   
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A hybrid functional-electrical stimulation (FES) gait system that incorporates a computer-controlled orthosis system has been developed to address the problems of rapid muscle fatigue and poor movement control that are characteristic of FES-aided gait. The orthosis is a long-leg brace that contains controllable friction brakes at both hip and knee joints. The system achieves desirable limb trajectories by utilizing the stimulated muscles as a source of unregulated power and regulating the power at each joint by computer control of the friction brakes. Muscle fatigue is reduced by locking the controllable brakes to provide the isometric joint torques necessary during stance. The hybrid gait system was evaluated and compared to conventional four channel FES-aided gait using four subjects with paraplegia. The results demonstrated significant reduction in muscle fatigue and improvement in trajectory control when using the orthosis combined with FES compared to using FES alone. Results for distance and speed improvements varied across subjects. Considerable work remains in the design of the hardware before the system is feasible for use outside the laboratory.  相似文献   
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In 3 experiments, adult male Long-Evans rats were castrated and treated daily with an anabolic-androgenic steroid (AAS) compound (either stanozolol, oxymetholone, or testosterone cypionate) for 6 weeks. Subjects were assigned to 5 groups that received injections of a high, medium, or low dose of the AAS, testosterone propionate, or the oil vehicle. Stanozolol failed to maintain ejaculation at any dose tested. Although some subjects receiving the low dose of oxymetholone ejaculated, oxymetholone generally failed to stimulate ejaculation above the levels of the oil group. Testosterone cypionate sustained ejaculation at all doses tested. The relative potency of the medium dose of each AAS in the sex accessory tissues was (from most potent to least potent): testosterone cypionate?>?stanozolol?=?oxymetholone?=?oil. Thus, these 3 AAS compounds produced a range of behavioral and endocrine responses in castrated male rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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To study the effects of complex environmental media on silver nanoparticle (AgNP) toxicity, AgNPs were added to microcosms with freshwater sediments and two species of aquatic plants (Potamogeton diversifolius and Egeria densa), followed by toxicity testing with microcosm surface water. Microcosms were designed with four environmental matrices in order to determine the contribution of each environmental compartment to changes in toxicity: water only (W), water + sediment (WS), water + plants (WP), and water + plants + sediment (WPS). Silver treatments included AgNPs with two different coatings, gum arabic (GA-AgNPs) or polyvinylpyrollidone (PVP-AgNPs), as well as AgNO(3). Water samples taken from the microcosms at 24 h postdosing were used in acute toxicity tests with two standard model organisms, early life stage zebrafish (Danio rerio) and Daphnia magna. Speciation of Ag in these samples was analyzed using Ag L3-edge X-ray absorption near edge spectroscopy (XANES). Silver speciation patterns for the nanoparticle treatments varied significantly by coating type. While PVP-AgNPs were quite stable and resisted transformation across all matrices (>92.4% Ag(0)), GA-AgNP speciation patterns suggest significantly higher transformation rates, especially in treatments with plants (<69.2% and <58.8% Ag(0) in WP and WPS, respectively) and moderately increased transformation with sediments (<85.6% Ag(0)). Additionally, the presence of plants in the microcosms (with and without sediments) reduced both the concentration of Ag in the water column and toxicity for all Ag treatments. Reductions in toxicity may have been related to decreased water column concentrations as well as changes in the surface chemistry of the particles induced by organic substances released from the plants.  相似文献   
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Interprocedural data flow information is useful for many software testing and analysis techniques, including data flow testing, regression testing, program slicing and impact analysis. For programs with aliases, these testing and analysis techniques can yield invalid results, unless the data flow information accounts for aliasing effects. Recent research provides algorithms for performing interprocedural data flow analysis in the presence of aliases; however, these algorithms are expensive, and achieve precise results only on complete programs. This paper presents an algorithm for performing alias analysis on incomplete programs that lets individual software components such as library routines, subroutines or subsystems be independently analyzed. The paper also presents an algorithm for reusing the results of this separate analysis when the individual software components are linked with calling modules. Our algorithms let us analyze frequently used software components, such as library routines or classes, independently, and reuse the results of that analysis when analyzing calling programs, without incurring the expense of completely reanalyzing each calling program. Our algorithms also provide a way to analyze large systems incrementally  相似文献   
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