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91.
Citations are very important parameters and are used to take many important decisions like ranking of researchers, institutions, countries, and to measure the relationship between research papers. All of these require accurate counting of citations and their occurrence (in-text citation counts) within the citing papers. Citation anchors refer to the citation made within the full text of the citing paper for example: ‘[1]’, ‘(Afzal et al, 2015)’, ‘[Afzal, 2015]’ etc. Identification of citation-anchors from the plain-text is a very challenging task due to the various styles and formats of citations. Recently, Shahid et al. highlighted some of the problems such as commonality in content, wrong allotment, mathematical ambiguities, and string variations etc in automatically identifying the in-text citation frequencies. The paper proposes an algorithm, CAD, for identification of citation-anchors and its in-text citation frequency based on different rules. For a comprehensive analysis, the dataset of research papers is prepared: on both Journal of Universal Computer Science (J.UCS) and (2) CiteSeer digital libraries. In experimental study, we conducted two experiments. In the first experiment, the proposed approach is compared with state-of-the-art technique over both datasets. The J.UCS dataset consists of 1200 research papers with 16,000 citation strings or references while the CiteSeer dataset consists of 52 research papers with 1850 references. The total dataset size becomes 1252 citing documents and 17,850 references. The experiments showed that CAD algorithm improved F-score by 44% and 37% respectively on both J.UCS and CiteSeer dataset over the contemporary technique (Shahid et al. in Int J Arab Inf Technol 12:481–488, 2014). The average score is 41% on both datasets. In the second experiment, the proposed approach is further analyzed against the existing state-of-the-art tools: CERMINE and GROBID. According to our results, the proposed approach is best performing with F1 of 0.99, followed by GROBID (F1 0.89) and CERMINE (F1 0.82). 相似文献
92.
The strain-rate sensitivity of strength is a significant factor to evaluate the deformation mode of crystalline materials. The strain rate sensitivity of hardness is experimentally investigated here for hydroxyapatite coatings that are sputter deposited onto titanium-coated silicon wafers. These biocompatible HA coatings can provide a strong, dense interface between metal alloy implants and porous hydroxyapatite that can help in-growth of tissue. The interface to the metal alloy implant is important to transfer stress during loading. So, it is very important to know the behavior of the coating under different conditions of loading. Our dynamic test procedure now takes advantage of nanoscratch testing to measure the change in scratch hardness of the coating over a strain rate range that may well simulate the mechanical loading conditions found at the interface between implants and hydroxyapatite coatings. 相似文献
93.
Daniel L. Dietrich Vedha Nayagam Michael C. Hicks Paul V. Ferkul Frederick L. Dryer Tanvir Farouk Benjamin D. Shaw Hyun Kyu Suh Mun Y. Choi Yu Cheng Liu C. Thomas Avedisian Forman A. Williams 《Microgravity science and technology》2014,26(2):65-76
This paper summarizes the first results from isolated droplet combustion experiments performed on the International Space Station (ISS). The long durations of microgravity provided in the ISS enable the measurement of droplet and flame histories over an unprecedented range of conditions. The first experiments were with heptane and methanol as fuels, initial droplet droplet diameters between 1.5 and 5.0 m m, ambient oxygen mole fractions between 0.1 and 0.4, ambient pressures between 0.7 and 3.0 a t m and ambient environments containing oxygen and nitrogen diluted with both carbon dioxide and helium. The experiments show both radiative and diffusive extinction. For both fuels, the flames exhibited pre-extinction flame oscillations during radiative extinction with a frequency of approximately 1 H z. The results revealed that as the ambient oxygen mole fraction was reduced, the diffusive-extinction droplet diameter increased and the radiative-extinction droplet diameter decreased. In between these two limiting extinction conditions, quasi-steady combustion was observed. Another important measurement that is related to spacecraft fire safety is the limiting oxygen index (LOI), the oxygen concentration below which quasi-steady combustion cannot be supported. This is also the ambient oxygen mole fraction for which the radiative and diffusive extinction diameters become equal. For oxygen/nitrogen mixtures, the LOI is 0.12 and 0.15 for methanol and heptane, respectively. The LOI increases to approximately 0.14 (0.14 O 2/0.56 N 2/0.30 C O 2) and 0.17 (0.17 O 2/0.63 N 2/0.20 C O 2) for methanol and heptane, respectively, for ambient environments that simulated dispersing an inert-gas suppressant (carbon dioxide) into a nominally air (1.0 a t m) ambient environment. The LOI is approximately 0.14 and 0.15 for methanol and heptane, respectively, when helium is dispersed into air at 1 atm. The experiments also showed unique burning behavior for large heptane droplets. After the visible hot flame radiatively extinguished around a large heptane droplet, the droplet continued to burn with a cool flame. This phenomena was observed repeatably over a wide range of ambient conditions. These cool flames were invisible to the experiment imaging system but their behavior was inferred by the sustained quasi-steady burning after visible flame extinction. Verification of this new burning regime was established by both theoretical and numerical analysis of the experimental results. These innovative experiments have provided a wealth of new data for improving the understanding of droplet combustion and related aspects of fire safety, as well as offering important measurements that can be used to test sophisticated evolving computational models and theories of droplet combustion. 相似文献
94.
Scientometrics - Until the late 90’s, conventional bibliometric indices such as, publication count, citation count, and number of co-authors have extensively been employed by the scientific... 相似文献
95.
Tensile testing of porous silver membranes is used to assess the postulate that the onset of plasticity corresponds with a shear type of deformation. The filament size and porosity take the parametric roles of feature size and free volume that are used to characterize the strain rate sensitivity of strength in nanoscale metals as now adapted for porous membranes. Experimental measurements indicate the porous membranes stiffen under tensile loading as plastic deformation progresses, as evidenced by an increase in the elastic modulus from a value consistent with the C′ elastic constant towards the C44 elastic constant. 相似文献
96.
Engineering services provided by one of the writers to property owners, insurance companies, attorneys, and others have resulted in a compilation of case studies, based on more than 1,000 site inspections, suitable to generate a database regarding various aspects of building performance. The scope of those services typically included identifying the cause and origin of damage to residential and commercial structures, as well as an estimation of the magnitude of damage sustained by those structures. The majority of those damaged structures was located in proximity to a coastal region and experienced recent exposure to a storm or other weather event. Compilation of data from those case studies allowed identification and ranking of the occurrence of chronic building problems. It has become apparent that building-related deficiencies often exist as a common feature in similar structures. Some of those recurring deficiencies could be eliminated with alternate building design, better construction practices, or proper routine maintenance procedures. Where applicable, proposed remedial solutions are presented for specific building deficiencies or problems identified. 相似文献
97.
Dewan Tanvir Ahmed M. Anwar Hossain Shervin Shirmohammadi Abdullah AlGhamdi Pradeep K. Atrey Abdulmotaleb El Saddik 《Multimedia Tools and Applications》2014,73(1):219-240
Design and implementation of an effective surveillance system is a challenging task. In practice, a large number of CCTV cameras are installed to prevent illegal and unacceptable activities where a human operator observes different camera views and identifies various alarming cases. But reliance on the human operator for real-time response can be expensive as he may be unable to pay full attention to all camera views at the same time. Moreover, the complexity of a situation may not be easily perceivable by the operator for which he might require additional support in response to an adverse situation. In this paper, we present a Decision Support Engine (DSE) to select and schedule most appropriate camera views that can help the operator to take an informed decision. For this purpose, we devise a utility based approach where the utility value changes based on automatically detected events in different surveillance zones, event co-relation, and operator’s feedback. In addition to the selected camera views, we propose to synthetically embed extra information around the camera views such as event summary and suggested action plan to globally perceive the current situation. The experimental results show the usefulness of the proposed decision support system. 相似文献
98.
A simple "routine" beam on elastic foundation finite element using a polynomial displacement function has been developed which yields acceptably accurate deflection, shear and bending moment values for prismatic or non-prismatic beams of elastic material resting on foundations with varying or nonlinear subgrade reactions. Limited extension of the formulation to an "exact" finite element using the exact displacement function of a beam on elastic foundation has also been carried out. The subgrade is represented by a non-homogeneous solid medium to include nonlinear parameters if required. The iterative solution is extended to cases where the beam may uplift because the foundation is a no tension material. The model is also suitable for calculating the elastic deflections, membrane. and bending stress resultants for axisymmetrically loaded variable thickness shells of revolution. A computer program called FEBEF [finite element: beam on elastic foundation] incorporating the routine finite element has been prepared for the solution of beams on elastic foundations and axi symmetrically loaded shells of revolution. 相似文献
99.
Mirza Sajjad Hussain Mazhar Mehmood Jamil Ahmad M. Tauseef Tanvir A. Faheem Khan Turab Ali Arshad Mahmood 《Materials Chemistry and Physics》2013
Rutherford Backscattering Spectrometry (RBS) has been employed for studying inter-layer diffusion and mixing of TiO2 and germanium in the multi-layers grown on the soda lime glass substrate. TiO2 layers were grown by electron-beam evaporation of titanium in an oxygen atmosphere and Ge layers were grown by resistive heating. UV–visible and Raman spectroscopy were carried out for optical characterization. RBS spectra were analyzed by SIMNRA which confirmed the successful formation of alternate layers of TiO2 and Ge with a thickness of 20 nm and 15 nm, respectively. Annealing caused interface mixing. The approximate stoichiometry of interfaces was of GeTiO2. The thickness of these layers increased with annealing temperature. Two to five top Ge layers also underwent oxidation to form GeO and GeO2, depending on annealing temperature. Nuclear Reaction Analysis (NRA) signal of oxygen from top layers was also recorded to confirm the pick-up of oxygen from the annealing atmosphere. An increase in the transmission efficiency with blue shift of the absorption edge was also observed with annealing temperature, as associated with the decrease in the effective thickness of Ge layers. Shift of Raman peaks confirmed the stoichiometric changes as a result of annealing. 相似文献
100.