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101.
Huaizhong Zhang Chunbo Luo Qi Wang Matthew Kitchin Andrew Parmley Jesus Monge-Alvarez Pablo Casaseca-de-la-Higuera 《Multimedia Tools and Applications》2018,77(20):26657-26676
This paper presents a new, practical infrared video based surveillance system, consisting of a resolution-enhanced, automatic target detection/recognition (ATD/R) system that is widely applicable in civilian and military applications. To deal with the issue of small numbers of pixel on target in the developed ATD/R system, as are encountered in long range imagery, a super-resolution method is employed to increase target signature resolution and optimise the baseline quality of inputs for object recognition. To tackle the challenge of detecting extremely low-resolution targets, we train a sophisticated and powerful convolutional neural network (CNN) based faster-RCNN using long wave infrared imagery datasets that were prepared and marked in-house. The system was tested under different weather conditions, using two datasets featuring target types comprising pedestrians and 6 different types of ground vehicles. The developed ATD/R system can detect extremely low-resolution targets with superior performance by effectively addressing the low small number of pixels on target, encountered in long range applications. A comparison with traditional methods confirms this superiority both qualitatively and quantitatively. 相似文献
102.
Jose Portillo-Portillo Roberto Leyva Victor Sanchez Gabriel Sanchez-Perez Hector Perez-Meana Jesus Olivares-Mercado Karina Toscano-Medina Mariko Nakano-Miyatake 《Applied Intelligence》2018,48(5):1200-1217
This paper proposes a view-invariant gait recognition algorithm, which builds a unique view invariant model taking advantage of the dimensionality reduction provided by the Direct Linear Discriminant Analysis (DLDA). Proposed scheme is able to reduce the under-sampling problem (USP) that appears usually when the number of training samples is much smaller than the dimension of the feature space. Proposed approach uses the Gait Energy Images (GEIs) and DLDA to create a view invariant model that is able to determine with high accuracy the identity of the person under analysis independently of incoming angles. Evaluation results show that the proposed scheme provides a recognition performance quite independent of the view angles and higher accuracy compared with other previously proposed gait recognition methods, in terms of computational complexity and recognition accuracy. 相似文献
103.
104.
Tatiana Lopes Fialho Evandro Martins Arlan Caldas Pereira Silveira Carolina Rodrigues de Jesus Silva Pierre Schuck 《Drying Technology》2018,36(8):922-931
Industrial production of lactose hydrolyzed milk powder (LHMP) remains challenging. Due to the presence of the monosaccharides glucose and galactose, lactose-free powders tend to suffer stickiness, caking, and browning during drying and storage. We sought to find ideal conditions spray dryer inlet air temperature (θair,in) and concentrated milk flow rate (mCM) for LHMP production. We tested θair,in settings of 115–160°C and mCM of 0.3–1.5?kg?·?h?1, and also applied mass and energetic balances. LHMP generally exhibited higher mass and energetic losses than the control (milk powder containing lactose), as a consequence of the relatively low dryability of LHMP. For a lab scale spray dryer, the ideal conditions settings for LHMP production were θair,in?=?145?±?2°C and mCM?=?1.0?kg?·?h?1, taking into account the mass yield and energetic cost (kJ?·?kg?1 of powder) of the process. These ideal conditions are a potential tool for the industrial development of lactose-free dairy powders. 相似文献
105.
J.R. Jesus R.J.S. Lima K.O. Moura J.G.S. Duque C.T. Meneses 《Ceramics International》2018,44(4):3585-3589
In this work, we report on the anisotropic growth of -Fe2O3 nanoslabs which are produced by co-precipitation method with the addition of sucrose. In our previous work, we have argued that such behavior can be related with the chelating agent. Experiments of X-ray diffraction (XRD), high-resolution transmission electronic microscopy (HRTEM) and magnetic measurements as a function of temperature and an applied magnetic field are used to characterize the samples. The HRTEM image of the sample prepared with 10 mmol/l of sucrose consists of faceted-like nanoslabs while that prepared without sucrose exhibits particles with a non-uniform shape. In this way, we can state that both the HRTEM images and the analysis of the XRD patterns show clearly a preferential growth of the [110] crystallographic direction. To strengthen our supposition, besides T- and field-dependence of magnetization are consistent with a superparamagnetic behavior the fit of the (Zero Field Cooling and Field Cooling) ZFC-FC curve for sample grown with 10 mmol/l of sucrose presents a strong increase of the effective anisotropy constant, , which can be related with the increasing of the shape magnetic anisotropy. 相似文献
106.
Jesus Iñarrea 《Journal of Electronic Materials》2017,46(7):3862-3866
In this work, we investigated the magnetotransport under terahertz radiation in high-mobility two-dimensional electron systems, focusing on irradiation by bichromatic and multichromatic terahertz sources. We observed strong modulation of the Shubnikov-de Haas oscillations at sufficient terahertz radiation power. We determined that the origin of the modulation was the interference between the average distance advanced by the scattered electrons between irradiated Landau states and the available initial density of states at a certain magnetic field. In the case of multifrequency illumination, we found that with the appropriate frequencies, the irradiated magnetoresistance could reach an almost zero-resistance state regime even at moderate radiation power. 相似文献
107.
The oxidation of protocatechuic acid with ozone in aqueous solution has been studied varying the temperature, pH, ozone partial pressure and initial acid concentration. A stoichiometric ratio of 2 mol of ozone consumed per mol of protocatechuic acid reacted is deduced from homogeneous experiments in a discontinuous tank reactor.In the ozonation experiments, the influence of the operating variables was established and the kinetic regime of ozone absorption was shown to be fast and pseudo m-order with respect to ozone, except at pH 2, when the reaction develops in the moderate kinetic regime. After applying a mass transfer with chemical reaction model, the reaction orders are deduced and the kinetic rate constants are determined as a function of pH and temperature. A modified Arrhenius expression is proposed to correlate them. 相似文献
108.
Comparative B‐mode and Doppler renal ultrasonography with histopathological findings in dogs positive for canine visceral leishmaniasis 下载免费PDF全文
Pollyana Irene Baltazar Laecio Da Silva Moura Gerson Tavares Pessoa Renan Paraguassu De Sá Rodrigues Marina Pinto Sanches Anaemilia Das Neves Diniz Francisco Das Chagas Araújo Sousa Porfírio Candanedo Guerra Willams Costa Neves Robson Fortes Giglio Jacyara De Jesus Rosa Pereira Alves Francisco De Assis Leite Souza Juliana Fortes Vilarinho Braga Flávio Ribeiro Alves 《Microscopy research and technique》2016,79(7):637-645
Morphological parameters and renal flow were assessed and measured in six clinically healthy dogs with negative serological and parasitological examinations for canine visceral leishmaniasis (CVL) and six dogs with CVL‐positive serological and parasitological tests and asymptomatic condition of the disease. Kidney length and diameter were measured and compared with the aorta/kidney ratio. Alterations in flow were measured using the flow velocity (cm/s) and resistance index (RI). Renal function was assessed by serum biochemical examination (urea, creatine, total proteins, albumin, and globulin) and urinalysis. CVL‐positive animals presented heterogeneous kidney echotexture, reduced vascular flow, hypoperfusion, lesser visualization of the arcuate arteries, high RI values (1.06 ± 0.28 for the right kidney and 1.10 ± 0.30 for the left kidney), reduced diastolic flow, and high systolic peak. They also presented positive creatine/RI correlation and between the renal artery vascular flow and kidney diameter. Histopathological analysis of CVL‐positive animals was compatible and confirmed hemodynamic changes observed by Doppler ultrasound. The findings in the present study showed that Doppler ultrasonography is a valid method to assess and detect alterations in flow in renal pathological processes with kidney vascular damage, as in the case of leishmaniasis, and can help in the diagnosis of animals with this infection. Microsc. Res. Tech. 79:637–645, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
109.
Luis Esteva Orlando Javier Díaz-López Alberto Vásquez Jesus Alberto León 《Structure and Infrastructure Engineering》2016,12(7):848-860
Seismic reliability and expected performance functions of structural systems are sensitive to the process of damage accumulation associated with the random sequences of ground motion excitations that those systems may experience. Optimum life cycle-based engineering decisions must examine the influence of concepts related to both the target safety level of the initial system and the eventual repair and maintenance actions that may be undertaken during the life of the system. This study includes an overview of the general framework supporting these decisions as well as some available results about (a) the influence of damage accumulation of the seismic vulnerability functions of building structures, (b) approximate estimates of accumulated damage and (c) optimum damage threshold values for repair of structural frames or replacement of energy dissipating devices. Some comments are presented concerning desirable studies about life cycle optimisation of systems exposed to different types of excitations. 相似文献
110.
Jesus E. Molinar-Solis Felipe Gomez-Castaneda Jose A. Moreno-Cadenas Victor H. Ponce-Ponce 《The Journal of VLSI Signal Processing》2007,49(1):207-216
At present, the Cellular Neural Network (CNN) is a potential parallel structure able to perform image processing tasks in
real-time when is effectively implemented in CMOS technology. The CNN silicon integration success is due mainly to the local
connectivity of processing cells. In this work, an alternative design based on floating-gate MOS inverters is presented, which
uses unipolar signals for solving binary tasks. The approach brings a fast response in a reduced silicon area, as shown through
electrical simulations. A prototype cell in CMOS technology (AMI, 1.2 micron) was fabricated and tested for eight image processing
tasks.
相似文献
Victor H. Ponce-Ponce |