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21.
Triacylglycerols of Finnish winter butterfat containing one saturated and two monoenoic fatty acyl residues were studied.
With silver ion high-performance liquid chromatography (HPLC), molecules were separated according to the difference in the
configuration of one fatty acyl moiety. The distribution of the saturatedcis,trans-dimonoenoic and saturatedcis,cis-dimonoenoic triacylglycerols according to their acyl carbon numbers was compared by means of reversed-phase HPLC and tandem
mass spectrometry. Furthermore, two examples of the fatty acid composition of a specified molecular weight species were shown.
The fatty acid compositions of corresponding saturatedcis,trans-dimonoenoic and saturatedcis,cis-dimonoenoic triacylglycerols were similar; however, there may be differences in the proportions of different fatty acid combinations
or in the distribution of fatty acids between primary and secondary glycerol positions. 相似文献
22.
The aim of the present study was to replicate the distinction between errors, lapses and violations, and to identify aggressive violations from normal or highway code violations. Furthermore, the relationship of these behaviours with road traffic accidents was examined. A total number of 1126 Finnish drivers completed a questionnaire containing the Driver Behaviour Questionnaire (DBQ) with extended violations scale, and questions regarding background information, such as age, gender and mileage. Also, questions about previous accidents and fines were asked. Factor analysis showed that a four-factor structure seemed more appropriate than the earlier established three-factor structure. The four factors were errors, lapses, speeding violations and interpersonal violations. The two types of violations result from different motives, and seem to be associated with different kinds of affect. Both interpersonal and speeding violations were reported most by young males, which was consistent with earlier findings. Logistic regression analyses indicated that errors predicted active accident involvement after partialling out the effects of demographic variables, whereas interpersonal violations were positively related to involvement in passive accidents. This was presumably due to different reporting tendencies of respondents. Speeding tickets were predicted by speeding and interpersonal violations and lapses and penalties for speeding by both kinds of violations and errors. Penalties for speeding, parking and other offences were predicted by interpersonal violations. The implications of these results are discussed. 相似文献
23.
Jensen OC Sørensen JF Kaerlev L Canals ML Nikolic N Saarni H 《Accident; analysis and prevention》2004,36(3):405-413
International surveys of occupational injuries among seafarers have so far been missing. It was the aim to test the method of self-report of injuries and length of time at risk during the latest duty period and second to study the injury incidence rate among seafarers by use of the method. A pilot study was conducted (n = 1068) in Finland, Denmark, the Philippines, Croatia and Spain using self-completed questionnaires with questions about the person, the ship, the duration of latest duty period and injuries. The duration of the self-reporting duty period was in the Danish part compared with information from the crew register of the Maritime Authority. For seafarers from merchant ships in the Danish sub-study there was acceptable correspondence between the information from the seafarers and the Maritime Authority, but not when referring to ferries and non-specified types of ship. Unadjusted and adjusted injury incidence rates-ratios (IRRs) based on number of injuries per number of work hours were calculated. Adjusted IRRs for ordinary seamen/officers: IRR = 2.43 (95% CI: 1.25-4.72); for age < 35/35+ years: IRR = 1.97 (1.02-3.81); length of tour: 117 days or longer compared with < 117 days: IRR = 0.46 (95% CI: 0.22-0.95); 57-70 working hours per week compared with < 57 h: IRR = 1.26 (0.48-3.29), 71+h compared with < 57 h: IRR = 2.12 (0.84-5.36). Non-significant IRRs >1.00 were found for ships under 10,000 GT compared with larger ships and for own flagged ships compared with ships under flag of convenience. In conclusion, more than 70 h of work per week was related to a higher rate of injuries for seafarers on merchant ships, but the result was not statistically significant. Self-report of the duration of the latest tour of duty is useful for seafarers from merchant ships with short-term employments, but not for ferries and other, non-specified types of ship with other or permanent employment. 相似文献
24.
A gas chromatographic method for the determination of tyrosol and tryptophol in wines and beers has been developed. The aromatic fusel alcohols are extracted with ether or ethyl acetate from a sample made alkaline with Na2CO3 and saturated with NaCl. In beer determinations the extraction is performed with ethyl acetate in order to avoid complications caused by emulsion. Most of the solvent is removed by distillation and the rest is cautiously allowed to evaporate. The gas chromatographic determination of tyrosol and tryptophol is performed in a 0·5-m. Apiezon M-DEGS column at 190°C. According to the infra-red spectra, both components are eluted without being decomposed at this temperature. In the grape wines investigated, tyrosol was found in amounts of 10–40 mg. per litre, in two Finnish berry wines 10–15 mg. per litre and in two different types of pale lager beers 5–10 mg. per litre. The same samples contained about 1–4 mg. tryptophol per litre. The two white grape wines and one red berry wine were exceptional, with only 0·2–0·3 mg. tryptophol per litre. 相似文献
25.
An average “real” process is determined from 55 processes automated by an automation system. This a first step in developing realistic benchmark processes for making objective evaluation tests between the performance of different automation systems. The most important properties of the average process that are independent of the automation system used and that are important performance indicators are presented in the paper.The real process, representing the statistical mean of the process data best, is a papermachine with a pulp making department. The process has 141 analog inputs, 50 binary inputs, 90 analog outputs, 63 binary outputs, 77 motor controls, 8 motor value controls, 308 process interfaces, and 165 displays. 相似文献
26.
Development of color density concept with color difference formulas in respect to human vision system 总被引:1,自引:0,他引:1
Arto Kaarna Wei Liu Heikki K?lvi?inen 《Frontiers of Electrical and Electronic Engineering in China》2011,6(2):381-387
The aims of this study are to develop the color density concept and to propose the color density based color difference formulas. The color density is defined using the metric coefficients that are based on the discrimination ellipses and the locations of the colors in the color space. The ellipse sets are the MacAdam ellipses in the CIE 1931 xy-chromaticity diagram and the chromaticity-discrimination ellipses in the CIELAB space. The latter set was originally used to develop the CIEDE2000 color difference formula. The color difference can be calculated from the color density for the two colors under consideration. As a result, the color density represents the perceived color difference more accurately, and it could be used to characterize a color by a quantity attribute matching better to the perceived color difference from this color. Resulting from this, the color density concept provides simply a correction term for the estimation of the color differences. In the experiments, the line element formula and the CIEDE2000 color difference formula performed better than the color density based difference measures. The reason behind this is in the current modeling of the color density concept. The discrimination ellipses are typically described with three-dimensional data consisting of two axes, the major and the minor, and the inclination angle. The proposed color density is only a one-dimensional corrector for color differences; thus, it cannot capture all the details of the ellipse information. Still, the color density gives clearly more correct estimations to perceived color differences than Euclidean distances using directly the coordinates of the color space. 相似文献
27.
Aqueous solutions of poly(vinyl pyrrolidone)-fullerene complexes (PVP-C70) have been studied using static and dynamic light scattering methods. Two diffusive processes were detected. The slow diffusion was interpreted as dynamics of large intermolecular PVP-C70 complexes while the fast diffusion was associated with the presence of individual PVP molecules in solution. It was also shown that the molecular weights and dimensions of PVP-C70 complexes are smaller than for PVP-C60 by a factor of 2.5-3. In aqueous solutions of PVP-C70 complex the depolarization and dissymmetry of scattered light were observed in contrast to PVP-C60 solutions. It reveals the existence of anisotropic structures in PVP-C70 solutions. Intermolecular interactions within PVP-C70 complexes are weak and a hydrodynamic field can destroy complexes. 相似文献
28.
Jiaxi Fang Juha Kangasluoma Michel Attoui Heikki Junninen Markku Kulmala 《Aerosol science and technology》2018,52(3):277-286
The ability to properly scale the synthesis of advanced materials through combustion synthesis routes is limited by our lack of knowledge regarding the initial stages of particle formation. In flame aerosol reactors, the high temperatures, fast reaction rates, and flame chemistry can all play a critical role in determining the properties of the resulting nanomaterials. In particular, multicomponent systems pose a unique challenge as most studies rely on empirical approaches toward designing advanced composite materials. The lack of predictive capabilities can be attributed to a lack of data on particle inception and growth below 2 nm. Measurements for the initial stages of particle formation during the combustion synthesis of SiO2 and composite SiO2/TiO2 using an atmospheric pressure inlet time-of-flight mass spectrometer are presented. Both positively and negatively charged clusters can be measured and results show the presence of silicic acid species which grow through dehydration, hydrogen abstraction, and interactions with hydroxyl radicals. In the case of composite SiO2/TiO2 particle formation, new molecular species containing Ti atoms emerge. Tandem differential mobility analysis-mass spectrometry (DMA-MS) provided further insight into the size-resolved chemistry of particle formation to reveal that at each cluster size, further hydroxyl-driven reactions take place. From this we can conclude that previous assumptions on collisional growth from simple monomer species of SiO2 and TiO2 do not sufficiently describe the collisional growth mechanisms for particle growth below 2 nm.
Copyright © 2018 American Association for Aerosol Research 相似文献
29.
DSP software development has been tied down by extreme computational requirements. Furthermore, the DSP development tools available today are less advanced than in other embedded software design. This has lead to DSP software architectures that have not taken into account future expansion needs. Therefore, DSP software architectures have been inherently closed. Now, as system complexity increases, this design methodology becomes more of a burden, since it does not support component-based DSP software development that requires open interfaces.
In this paper, mobile-communications DSP software architectures are studied as cases, and key areas for improvements towards more open DSP software development are identified. Proposed solutions are judged against the limited resources of mobile communication terminals and the characteristics of communication DSPs. 相似文献
30.
Nataliya Strokina Aki Mankki Tuomas Eerola Lasse Lensu Jari Käyhkö Heikki Kälviäinen 《Machine Vision and Applications》2013,24(4):869-881
One important aspect of assessing the quality in pulp and papermaking is dirt particle counting and classification. Knowing the number and types of dirt particles present in pulp is useful for detecting problems in the production process as early as possible and for fixing them. Since manual quality control is a time-consuming and laborious task, the problem calls for an automated solution using machine vision techniques. However, the ground truth required to train an automated system is difficult to ascertain, since all of the dirt particles should be manually segmented and classified based on image information. This paper proposes a framework for developing and tuning dirt particle detection and classification systems. To avoid manual annotation, dry pulp sheets with a single dirt type in each were exploited to generate semisynthetic images with the ground truth information. To classify the dirt particles, a set of features were computed for each image segment. Sequential feature selection was employed to determine a close-to-optimal set of features to be used in classification. The framework was tested both with semisynthetically generated images based on real pulp sheets and with independent original real pulp sheets without any generation. The results of the experiments show that the semisynthetic procedure does not significantly change the properties of images and has little effect on the particle segmentation. The feature selection proved to be important when the number of dirt classes changes since it allows to improve the classification results. Using the standard classification methods, it is possible to obtain satisfactory results, although the methods modeling the data, such as the Bayesian classifier using the Gaussian Mixture Model, show better performance. 相似文献