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61.
62.
While recent building code advancements have reduced structural failures in residential buildings during hurricane events, water intrusion through the building envelope is a recurring problem. Water ingress poses a significant threat to the building interior and its contents. The interface between the window and the wall system has been identified as a significant source of this water ingress. The fenestration industry has made extensive efforts to develop installation methods to improve water tightness; however, the body of research needed to guide window installations in high-humidity, hurricane-prone areas is sparse. The goal of this research is to investigate the water penetration resistance of selected window installation options consistent with current construction practice of single-family homes when exposed to wind-driven rain.  相似文献   
63.
A novel method has been developed to reveal the possible existence of pore structure defects on the thin and ultra-thin separating layers of composite inorganic membranes. In this work the method is applied to sol–gel and CVD treated microporous membranes and involves a modified mercury porosimetry technique in which the only surface exposed for mercury intrusion is the one of the nanofiltration (NF) layer. The validity of the test method was verified by comparison with the outcome of gas phase permeability experiments. Defects of size above 5 nm are accurately and reliably detected. The size range from 3.6 nm to 5 nm, although “traceable” with normal mercury intrusion up to 60,000 psig, remains somewhat unexploited with the new technique. This is due to interferences induced by the elasticity properties (compression modulus and strength) of the material applied as a “plug” to membrane support. Continuity imperfections on the NF layer of a commercially available membrane were detected by application of the modified mercury intrusion technique. The area examined was about ∼7% of the total NF layer area exposed by the tube and the size of revealed defects was in the range between 20 nm and 100 nm. Furthermore sections of the defects bearing membrane were modified by chemical vapor deposition of SiO2 to examine the possibility of mending the existing cracks. Significant reduction of the defects size has been observed with the novel mercury intrusion technique.  相似文献   
64.
The interaction between cis- and trans- RuCl(2)(DMSO)(4) and human serum albumin have been investigated through UV-Vis, circular dichroism, fluorescence spectroscopy and inductively couplet plasma atomic emission spectroscopy (ICP(AES)) method Albumin can specifically bind 1 mole of cis-isomer and 2 moles of the trans-isomer RuCl(2)(DMSO)(4) complex. The interaction of RuCl(2)(DMSO)(4) with HSA causes: a conformational change with the loss of helical stability of protein; the strong quenching of the Trp 214 fluorescence indicating that the conformational change of the hydrophobic binding pocked in subdomain IIA takes place; a local perturbation of the warfarin binding site and induce some conformational changes at neighbour domains, a changing of the binding abilities towards heme.  相似文献   
65.
This work aims at facilitating the schedulability analysis of non-critical systems, in particular those that have soft real-time constraints, where worst-case execution times (WCETs) can be replaced by less stringent probabilistic bounds, which we call maximal execution times (METs). To this end, it is possible to obtain adequate probabilistic execution time models by separating the non-random dependency on input data from a modeling error that is purely random. The proposed approach first utilizes execution time multivariate measurements for building a multiple regression model and then uses the theory related to confidence bounds of coefficients, in order to estimate the upper bound of execution time. Although certainly our method cannot directly achieve extreme probability levels that are usually expected for WCETs, it is an attractive alternative for MET analysis, since it can arguably guarantee safe probabilistic bounds. The method’s effectiveness is demonstrated on a JPEG decoder running on an industrial SPARC V8 processor.  相似文献   
66.
Anti-SPIT policies counter the SPam over Internet Telephony (SPIT) by distinguishing bots launching unsolicited bulks of VoIP calls from human beings. We propose an Anti-SPIT Policy Management mechanism (aSPM) that detects spam calls and prevents VoIP session establishment by the Session Initiation Protocol (SIP). The SPIN model checker is used to formally model and analyze the robustness of the aSPM mechanism in execution scenarios with parallel SIP sessions. In case of a possible design flaw, the model checker provides a trace of the caught unexpected behavior (counterexample), that can be used for the revision of the mechanism’s design. Our SPIN model is parameterized, based on measurements from experiments with VoIP users. Non-determinism plays a key role in representing all possible anti-SPIT policy decisions, in terms of the SIP messages that may be exchanged. The model checking results provide evidence for the timeliness of the parallel SIP sessions, the absence of deadlocks or livelocks, and the fairness for the VoIP service users. These findings ensure robust anti-SPIT protection, meaning that the aSPM mechanism operates as expected, despite the occurrence of random SPIT calls and communication error messages. To the best of our knowledge, this is the first analysis for exhaustively searching security policy flaws, due to complex interactions between anti-SPIT measures and the SIP protocol services.  相似文献   
67.
A new method is developed to estimate daily turbulent air–sea fluxes over the global ocean on a 0.25° grid. The required surface wind speed (w 10) and specific air humidity (q 10) at 10 m height are both estimated from remotely sensed measurements. w 10 is obtained from the SeaWinds scatterometer on board the QuikSCAT satellite. A new empirical model relating brightness temperatures (T b) from the Special Sensor Microwave Imager (SSM/I) and q 10 is developed. It is an extension of the author's previous q 10 model. In addition to T b, the empirical model includes sea surface temperature (SST) and air–sea temperature difference data. The calibration of the new empirical q 10 model utilizes q 10 from the latest version of the National Oceanography Centre air–sea interaction gridded data set (NOCS2.0). Compared with mooring data, the new satellite q 10 exhibits better statistical results than previous estimates. For instance, the bias, the root mean square (RMS), and the correlation coefficient values estimated from comparisons between satellite and moorings in the northeast Atlantic and the Mediterranean Sea are –0.04 g kg?1, 0.87 g kg?1, and 0.95, respectively. The new satellite q 10 is used in combination with the newly reprocessed QuikSCAT V3, the latest version of SST analyses provided by the National Climatic Data Center (NCDC), and 10 m air temperature estimated from the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalyses (ERA-Interim), to determine three daily gridded turbulent quantities at 0.25° spatial resolution: surface wind stress, latent heat flux (LHF), and sensible heat flux (SHF). Validation of the resulting fields is performed through a comprehensive comparison with daily, in situ values of LHF and SHF from buoys. In the northeast Atlantic basin, the satellite-derived daily LHF has bias, RMS, and correlation of 5 W m?2, 27 W m?2, and 0.89, respectively. For SHF, the statistical parameters are –2 W m?2, 10 W m?2, and 0.94, respectively. At global scale, the new satellite LHF and SHF are compared to NOCS2.0 daily estimates. Both daily fluxes exhibit similar spatial and seasonal variability. The main departures are found at latitudes south of 40° S, where satellite latent and sensible heat fluxes are generally larger.  相似文献   
68.
ABSTRACT:  The effect of high hydrostatic pressure (HHP) (100 to 700 MPa) combined with temperature (20 to 40 °C) on the activity of 5 aminopeptidases (PepN, PepX, PepY, PepC, and PepA) of Lactobacillus delbrueckii ssp. bulgaricus ACA-DC 0105, used as starter culture for feta cheese production, was studied. Aminopeptidases PepN, PepX, and PepA were activated at pressures up to 200 MPa, at temperatures up to 40 °C. PepY and PepC appeared to be more sensitive to pressure and temperature treatment leading to inactivation for pressures above 100 and 200 MPa, respectively, combined with temperature above 30 °C. A multi-parameter equation was used for predicting the activation of PepN, PepX, and PepA aminopeptidases in the pressure and temperature domain. Overall, processing at 200 MPa and 20 °C may be selected as the optimum conditions for maximum activation of 4 out of 5 aminopeptidases of L. delbrueckii ssp. bulgaricus. A 20-min treatment at these conditions leads to an average 3-fold increase in activity, which could lead to better and faster maturation of white cheese.  相似文献   
69.
Semiconductor nanowires have been playing a crucial role in the development of nanoscale devices for the realization of spin qubits, Majorana fermions, single photon emitters, nanoprocessors, etc. The monolithic growth of site-controlled nanowires is a prerequisite toward the next generation of devices that will require addressability and scalability. Here, combining top-down nanofabrication and bottom-up self-assembly, the growth of Ge wires on prepatterned Si (001) substrates with controllable position, distance, length, and structure is reported. This is achieved by a novel growth process that uses a SiGe strain-relaxation template and can be potentially generalized to other material combinations. Transport measurements show an electrically tunable spin–orbit coupling, with a spin–orbit length similar to that of III–V materials. Also, charge sensing between quantum dots in closely spaced wires is observed, which underlines their potential for the realization of advanced quantum devices. The reported results open a path toward scalable qubit devices using nanowires on silicon.  相似文献   
70.
Keeping quality of fresh orange juice is highly dependent on pectinolytic enzyme activity and the growth of spoilage microorganisms. The inactivation kinetics of indigenous pectin methylesterase (PME) and of the two more pressure resistant species of spoilage lactic acid bacteria (LAB) Lactobacillus plantarum and L. brevis in freshly squeezed Valencia orange juice under high hydrostatic pressure (100–500 MPa) combined with moderate temperature (20–40 °C) was investigated. PME inactivation followed first order kinetics with a residual PME activity (15%) at all pressure–temperature combinations used. The values of activation energy and activation volume were estimated at each pressure and at each temperature, respectively. Values of 90 kJ/mol and ?30 mL/mol at reference pressure of 300 MPa and reference temperature of 35 °C were estimated respectively. The corresponding zT and zP values of LAB inactivation were also estimated at all conditions tested. Values of 19.5 °C and 95 MPa at reference pressure of 300 MPa and reference temperature of 30 °C were estimated respectively for L. plantarum, while the corresponding values for L. brevis were 40 °C and 82 MPa, respectively, at the same reference conditions. Pressure and temperature were found to act synergistically both for PME and LAB inactivation. The PME and LAB inactivation rate constants were expressed as functions of the temperature and pressure process conditions. These functions allow the determination of the pressure/temperature conditions that achieve the target enzyme and microbial inactivation at a selected processing time. The process conditions of 350 MPa at 35 °C for 2 min are proposed as effective for Valencia orange juice cold pasteurisation.  相似文献   
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