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111.
Local and global mappings of topology representing networks 总被引:1,自引:0,他引:1
As data analysis tasks often have to deal with complex data structures, the nonlinear dimensionality reduction methods play an important role in exploratory data analysis. In the literature a number of nonlinear dimensionality reduction techniques have been proposed (e.g. Sammon mapping, Locally Linear Embedding). These techniques attempt to preserve either the local or the global geometry of the original data, and they perform metric or non-metric dimensionality reduction. Nevertheless, it is difficult to apply most of them to large data sets. There is a need for new algorithms that are able to combine vector quantisation and mapping methods in order to visualise the data structure in a low-dimensional vector space. In this paper we define a new class of algorithms to quantify and disclose the data structure, that are based on the topology representing networks and apply different mapping methods to the low-dimensional visualisation. Not only existing methods are combined for that purpose but also a novel group of mapping methods (Topology Representing Network Map) are introduced as a part of this class. Topology Representing Network Maps utilise the main benefits of the topology representing networks and of the multidimensional scaling methods to disclose the real structure of the data set under study. To determine the main properties of the topology representing network based mapping methods, a detailed analysis of classical benchmark examples (Wine and Optical Recognition of Handwritten Digits data set) is presented. 相似文献
112.
Simulation of thermal stress in reinforced concrete at early ages with a simplified model 总被引:3,自引:0,他引:3
Agnes Nagy 《Materials and Structures》1997,30(3):167-173
This paper is primarily concerned with stresses and cracking in reinforced concrete caused by restrained thermal deformations during the hydration process. Simulation of thermal stresses and crack occurrence is carried out with a simplified model. By validation against tests, it is shown that the simple, one-dimensional model gives a reasonable estimate of the thermal stress development. The model is based on a few input parameters like temperature history, stiffness development and tensile strength development. By means of a parametric investigation, the age-dependent stiffness of the concrete and the temperature history are identified as the decisive material characteristics regarding the thermal stress level. It is also found that the reinforcement has no effect prior to cracking but a clear crack redistributing role in the post-cracking state. 相似文献
113.
Intizar Hussain Deeptha Wijerathna Sigit S. Arif Murtiningrum Agnes Mawarni Suparmi 《Water Resources Management》2006,20(3):313-336
This paper analyzes irrigation-poverty linkages, and determines how and to what extent irrigation contributes to poverty alleviation,
and whether there are any spatial patterns in poverty in irrigation systems. It also identifies conditions under which irrigation
has greater anti-poverty impacts. The analysis is based on primary data collected during the 2000--2001 agricultural year,
from four selected irrigation systems and rainfed areas in Java. The results indicate that irrigation has significant poverty
reducing impacts. Poverty varies across irrigation systems and across locations within the systems. In general, crop productivity
is relatively higher and poverty is lower in middle parts of the systems compared to head and tail parts. Further, locational
differences in poverty are more pronounced in larger systems where locational inequities in water distribution and productivity
differences are also high. Crop productivity, the size of landholdings and location of households are important determinants
of poverty, in addition to demographic factors such as family size. The smaller the systems with well managed infrastructure,
relatively equitable water distribution and diversified cropping patterns supported with market infrastructure, the greater
the poverty reducing impacts of irrigation. Overall, the study findings suggest that improving the performance of irrigation
systems by enhancing land and water productivity, diversifying cropping patterns and improving water distribution across locations
would help reduce poverty in presently low productivity-high poverty parts of the systems. 相似文献
114.
Zschöck M Manhold-Maurer S Wescher A Merl K Khan I Lämmler C 《The Journal of dairy research》2005,72(3):333-337
Sixty-nine bovine mastitis streptococci belonging to the species Str. agalactiae (n = 13), Str. dysgalactiae (n = 16), Str. canis (n = 22), Str. uberis (n = 20) and Str. parauberis (n = 4) and six reference strains of the five streptococcal species were examined for their tRNA gene intergenic length polymorphism (tDNA-ILP) fingerprint pattern. Epidemiologically unrelated isolates from bovine mastitis cases were selected by macrorestriction analysis with pulsed-field gel electrophoresis (PFGE). Their results were compared with those obtained from biochemical and serological studies and with those obtained by PCR-mediated identification amplifying species-specific gene segments of the five streptococcal species. According to the present results tDNA-ILP allowed a correct identification of all Str. agalactiae, Str. uberis and Str. parauberis strains investigated also including the reference strains of each species showing species-specific banding pattern. However, all Str. dysgalactiae ssp. dysgalactiae and all Str. canis strains appeared with an undistinguishable pattern which did not allow an identification of the species. 相似文献
115.
116.
Peter Engelhart Nils‐Peter Harder Rainer Grischke Agnes Merkle Rüdiger Meyer Rolf Brendel 《Progress in Photovoltaics: Research and Applications》2007,15(3):237-243
We demonstrate mask‐free fabrication of a 22·0%‐efficient crystalline Si solar cell by applying laser ablation of Si and by laser ablation of protective coatings. The bulk absorber material is a p ‐type float zone silicon wafer and the designated cell area is 4 cm2. While the processing time of our laboratory‐type of laser system is far too slow for industrial processing, we estimate on the basis of our experiments that laser processing of 12·5 × 12·5 cm2‐sized solar cells in just a few seconds is feasible with commercially available equipment. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
117.
New Methods for Developing and Manufacturing Compliant Mechanisms Utilizing Bulk Metallic Glass 下载免费PDF全文
118.
The mycoflora of dried salted fish from Indonesia was studied, with emphasis on visibly spoiled fish and spoilage fungi. A total of 364 isolates from 74 fish were cultured and identified. The most prevalent fungus was a previously undescribed species, now named Polypaecilum pisce, which was isolated from 42% of the fish examined, in extreme cases appearing as conspicuous white growth over large areas of the fish surface. Other frequently isolated species were Eurotium rubrum (35%), E. repens (26%), E. amstelodami (22%), E. chevalieri (18%), Aspergillus niger (37%), A. flavus (27%), A. sydowii (23%), A. penicilloides (16%) and A. wentii (15%). A variety of Penicillium species and species from 17 other genera were isolated less frequently. 相似文献
119.
Florian Hägele Simone Nübling Ralf M. Schweiggert Svenja Baur Agnes Weiss Herbert Schmidt Alexander Menegat Roland Gerhards Reinhold Carle 《Food and Bioprocess Technology》2016,9(12):1979-1990
Superficial short-wavelength ultraviolet (UV-C) treatment (1.2 kJ/m2) of fresh-cut endive was combined with conventional cold (4 °C, 120 s) and innovative warm (45 °C, 120 s) water washing prior to and after irradiation in order to improve its microbial and sensory quality including physiological properties. UV-C doses applied exerted only minor physiological stress on the plant tissue, irrespective of the washing procedure as indicated by largely unaltered headspace gas compositions, chlorophyll fluorescence maximum quantum yields (F v/F m), and retention of chlorophylls and β-carotene. Independent of the washing procedure applied, phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO), and peroxidase (POD) activities were slightly inhibited by UV-C irradiation. As a result of UV-C irradiation, significantly improved microbiological and sensory quality was retained during the entire storage period, particularly, when applied after washing. Being applicable in organic fresh-cut production, UV-C represents a valuable alternative to chlorine application to washing water. The most efficient decontamination (2.1 log10 units) of fresh-cut endive was achieved by combining warm water washing with subsequent UV-C irradiation. Furthermore, when UV-C lamps were integrated into the water tank of a continuous industrial washing machine, the microbial loads of the process water were also significantly lowered. Accordingly, in-line UV-C decontamination of process water may be instrumental in minimizing both fresh water consumption and the risk of cross-contamination. 相似文献
120.
Clement Djameh Firibu Kwesi Saalia Emmanuel Sinayobye Agnes Budu Gloria Essilfie Henry Mensah‐Brown Samuel Sefa‐Dedeh 《Journal of the Institute of Brewing》2015,121(1):106-112
Pito is an alcoholic beverage obtained through a yeast (Saccharomyces cerevisiae) fermentation of wort extracted from sorghum (Sorghum bicolor L. Moench) malt. The malting conditions of sorghum are thought to influence the quality characteristics of the malt, and subsequently the quality of the pito obtained from it. Studies were carried out on a local sorghum cultivar grown in Ghana – chireh, to optimize the conditions for malting conditions for pito production in Ghana. A 33 full factorial experimental design was replicated with steeping times of 12, 16 and 22 h, germination times of 3, 4 and 5 days, and malt drying temperatures of 30, 40 and 50 °C as factors. Diastatic power, extract yield, attenuation limit and free amino nitrogen were determined. Germination duration significantly affected diastatic power and free amino nitrogen (p < 0.001). Extract yield was also significantly influenced by germination duration (p = 0.001). The germination time, steeping time and drying temperature had no significant effect on the attenuation limit. The optimal conditions for malting this specific cultivar grown in Ghana to obtain critical malt quality indices are 12.0–12.5 h steeping, 5 days of germination at 30 °C and drying at 40 °C. Free amino nitrogen levels in all treatments were higher than the minimum requirement for good yeast nutrition and fermentation. Copyright © 2015 The Institute of Brewing & Distilling 相似文献