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111.
Uncertain population behaviors in a regional emergency could potentially harm the performance of the region's transportation system and subsequent evacuation effort. The integration of behavioral survey data with travel demand modeling enables an assessment of transportation system performance and the identification of operational and public health countermeasures. This paper analyzes transportation system demand and system performance for emergency management in three disaster scenarios. A two-step methodology first estimates the number of trips evacuating the region, thereby capturing behavioral aspects in a scientifically defensible manner based on survey results, and second, assigns these trips to a regional highway network, using geographic information systems software, thereby making the methodology transferable to other locations. Performance measures are generated for each scenario including maps of volume-to-capacity ratios, geographic contours of evacuation time from the center of the region, and link-specific metrics such as weighted average speed and traffic volume.  相似文献   
112.
This paper presents fundamental aspects of MPLS over ATM method, IP over ATM method and multimedia application traffics with different quality of service (QoS) requirements. Using a simulation tool, the MPLS over ATM method providing ABR, CBR and VBR QoS support, and the IP over ATM method providing a primitive UBR QoS support for transferring data, voice and video traffics are modeled. Having simulated the models under varying offered loads, obtained simulation results are presented. Comparing the average end-to-end delay and delay variation graphs, not only does the MPLS over ATM method provide improved results for all of the multimedia traffics but also overcomes the worst disadvantage of the IP over ATM method producing similar and erratic results for the data, voice and video application traffics.  相似文献   
113.
The objectives of this work were to study the ultrasound- and ultraviolet light-induced inactivation kinetics of polyphenol oxidase extracted from different sources in a model system. The polyphenol oxidase crude extract was obtained from bananas, apples, quince, eggplants, plums, dill, and cultured mushrooms, which exhibited high enzyme activity. The polyphenol oxidase crude extract was treated with ultrasound and ultraviolet light at 40°C temperature for 40 min. The study showed that the polyphenol oxidase enzyme was inactivated between 12 and 100% during ultrasound only treatment; between 4 and 29% during ultraviolet light only treatment; and between 80 and 100% during simultaneous ultrasound and ultraviolet light treatment. Based on the measurements, an exponential decay model for determining polyphenol oxidase inactivation kinetics was developed. The model provides high determination coefficients (R2): 0.968–0.999 with ultrasound only treatment, 0.881–0.990 with ultraviolet only treatment, and 0.975–1.000 with simultaneous ultrasound and ultraviolet treatment. The polyphenol oxidase kinetics evaluation showed that different treatments provided different inactivation times, or D-values. The D-values were 7.0–656.1 min for ultrasound only treatment (DUS), 251–1887 min for ultraviolet only treatment (DUV), and 3.3–59.4 min for combined ultrasound and ultraviolet treatment (DUS+UV).  相似文献   
114.

Our recent research has been pioneering the generation of single solid particles with adjustable eccentricity. This new technique permits the production of particles in the range of 200 w m to 2 mm and an approximate eccentricity of 1:1.2 to 1:1.8 along an axis. Single droplets consisting of multiacrylate monomers were levitated by an ultrasonic levitator and were cured by UV illumination after adjusted eccentricity. For special applications we can produce particles that are attached to a stem (optical fiber), which allows a controlled orientation of the particle. One possible application for such particles is the investigation of light scattering on nonspherical particles.  相似文献   
115.
Automatic speaker verification (ASV) systems are highly vulnerable against spoofing attacks. Anti-spoofing, determining whether a speech signal is natural/genuine or spoofed, is very important for improving the reliability of the ASV systems. Spoofing attacks using the speech signals generated using speech synthesis and voice conversion have recently received great interest due to the 2015 edition of Automatic Speaker Verification Spoofing and Countermeasures Challenge (ASVspoof 2015). In this paper, we propose to use linear prediction (LP) residual based features for anti-spoofing. Three different features extracted from LP residual signal were compared using the ASVspoof 2015 database. Experimental results indicate that LP residual phase cepstral coefficients (LPRPC) and LP residual Hilbert envelope cepstral coefficients (LPRHEC) obtained from the analytic signal of the LP residual yield promising results for anti-spoofing. The proposed features are found to outperform standard Mel-frequency cepstral coefficients (MFCC) and Cosine Phase (CosPhase) features. LPRPC and LPRHEC features give the smallest equal error rates (EER) for eight spoofing methods out of ten spoofing attacks in comparison to MFCC and CosPhase features.  相似文献   
116.
Journal of Materials Science: Materials in Electronics - The illumination and voltage effects on the I-V measurements of the fabricated In/In2S3/p-Si photodiode were investigated in dark and under...  相似文献   
117.
118.
The experimental and theoretical study of methane adsorption on granular activated carbons is presented. The adsorption data are modeled by various isotherm equations. Toth equation is found to have the best fit. The isosteric heat decreases with loading and increases weakly with temperature, which is an indication of heterogeneity of the methane and granular activated carbon system. Using optimized parameters from Toth equation, a novel procedure is developed to calculate the integral heat of adsorption, which is the total amount of isosteric heat of adsorption at a given temperature and pressure during the adsorption process. © 2011 American Institute of Chemical Engineers AIChE J, 2012  相似文献   
119.
This study analyzes energy use and investigates influences of energy inputs and energy forms on output levels in Turkish agriculture during the period 1975–2000. The output level was calculated in the form of annual grain equivalent at aggregate level for 104 agricultural commodities except livestock products. Output level was specified as a function of total physical, fertilizer and seed energy, and ordinary least squares was employed to estimate equation parameters. The results show that total energy input has increased from 19.6 GJ/ha in 1975 to 45.7 GJ/ha in 2000, whereas total output energy has risen from 27.1 GJ/ha to a level of 39.1 GJ/ha. Energy efficiency indicators, input–output ratio, energy productivity and net energy have declined over the examined period. Total physical and fertilizer energy, particularly nitrogen, significantly contributed to output level with elasticities of 0.24 and 0.14, respectively. The results also revealed that non-renewable, direct and indirect energy forms had a positive impact on output level. Moreover, Turkish agriculture has experienced a substantial increase in non-renewable energy use. This inefficient energy use pattern in the Turkish agriculture can create some environmental problems such as increase in global warming, CO2 emissions, and non-sustainability. Thus, policy makers should undertake new policy tools to ensure sustainability and efficient energy use.  相似文献   
120.
A distributed power system consisting of two uninterrupted power supplies (UPS) is investigated in this paper. Parallel operation of the two sources increases the established power rating of the system. One of the sources can supply the system even when the other system is disconnected due to some faults, and this is an important feature. The control algorithm makes sure that the total load is shared between the supplies in accordance with their rated power levels, and the frequency of the supplies are restored to the rated values after the transitions. As the UPSs operate at an optimum power level, losses and faults due to overloading are prevented. The units safely operate without any means of communication between each other. The focus of the work is on the inverter stages of the UPSs. Simulations performed in Matlab Simulink environment have been verified with experimental work via DS1103 controller card.  相似文献   
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