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71.
Thomas Anung Basuki Antonio Cerone Andreas Griesmayer Rudolf Schlatte 《Formal Aspects of Computing》2009,21(6):571-588
This article describes a framework to formally model and analyse human behaviour. This is shown by a simple case study of
a chocolate vending machine, which represents many aspects of human behaviour. The case study is modelled and analysed using
the Maude rewrite system. This work extends a previous work by Basuki which attempts to model interactions between human and
machine and analyse the possibility of errors occurring in the interactions. By redesigning the interface, it can be shown
that certain kinds of error can be avoided for some users. This article overcomes the limitation of Basuki’s approach by incorporating
many aspects of user behaviour into a single user model, and introduces a more natural approach to model human–computer interaction. 相似文献
72.
Rudolf Herzog 《?sterreichische Wasser- und Abfallwirtschaft》2009,61(11-12):a30-a33
73.
Population data and apparent prevalence data from the Salmonella surveillance and control program in pigs (NSSCP) from 1998 and 1999 were used in a simulation model to evaluate the efficacy of the program. The model consists of three parts: modelling of individual prevalence at the abattoir (abattoir part), modelling of the number of sampled herds of different sizes when carcasses are randomly sampled at the abattoir (sampling strategy part) and finally, modelling of the within herd prevalence (within herd part). A total of 136,550 sows and 2,866,550 finishing pigs slaughtered, 4446 herds and 11 herds positive for Salmonella in 1994/1995-2000 were included in the abattoir part, sampling strategy part and the within herd part of the model, respectively. The abattoir part showed an average estimated prevalence of Salmonella in sows and finishing pigs of (median) 0.4% (5-95 percentiles = 0.03-2%) and 0.1% (0.04-0.2%) respectively. The estimated number of infected sow carcasses that entered the market was 502 (37-2157) while the estimated number of finishing pig carcasses was 2919 (1218-5771). The probability of being sampled for the 10% smallest herds was (mean) 1.9% (1.6-2.2), to 25% (24.7-26.5%) for the 10% largest herds. The within herd prevalence was estimated to be from 1% to 4% for Norwegian pig herds. The conclusions drawn from this evaluation are that the NSSCP does not have any significant consumer protection effect, and that the documentation could be done more effectively using the herd rather than the individual animal as the unit of sampling. Sampling should focus on the larger herds supplying most of the meat on the market and on herds that produce breeding sows and piglets and thus can contribute to the spread of Salmonella among herds. 相似文献
74.
Lütke-Eversloh T Fischer A Remminghorst U Kawada J Marchessault RH Bögershausen A Kalwei M Eckert H Reichelt R Liu SJ Steinbüchel A 《Nature materials》2002,1(4):236-240
The development of non-petrochemical sources for the plastics industry continues to progress as large multinationals focus on renewable resources to replace fossil carbon. Many bacteria are known to accumulate polyoxoesters as water-insoluble granules in the cytoplasm. The thermoplastic and/or elastomeric behaviour of these biodegradable polymers holds promise for the development of various technological applications. Here, we report the synthesis and characterization of microbial polythioesters (PTEs), a novel class of biopolymers of general technological relevance. Biosynthesis of PTE homopolymers was achieved using a recombinant strain of Escherichia coli that expressed a non-natural pathway consisting of a butyrate kinase, a phosphotransbutyrylase, and a PHA synthase. Different homopolymers were produced, consisting of either 3-mercaptopropionate, 3-mercaptobutyrate, or 3-mercaptovalerate repeating units, if the respective mercaptoalkanoic acids were provided as precursor substrates to the fermentative process. The PTEs contributed up to 30% (w/w) of the cellular dry weight and were identified as hydrophobic inclusions in the cytoplasm. The chemical and stereochemical homogeneity of the purified PTEs were identified by different methods, and the estimated physical properties were compared to the oxypolyester equivalents, revealing low crystalline order and, for the poly(3-mercaptopropionate) improved thermal stability. The ability to produce PTEs through a biosynthetic route opens up new avenues in the field of biomaterials. 相似文献
75.
Blom H Johansson M Gösch M Sigmundsson T Holm J Hård S Rigler R 《Applied optics》2002,41(31):6614-6620
We have developed a multifocal optical fluorescence correlation spectroscopy system for parallel flow analyses. Multifocal excitation was made possible through a 4 x 1 diffractive optical fan-out element, which produces uniform intensity in all four foci. Autocorrelation flow analyses inside a 20 microm x 20 microm square microchannel, with the 4 x 1 fan-out foci perpendicular to the flow direction, made it possible to monitor different flows in all four foci simultaneously. We were able to perform cross-correlation flow analyses by turning the microstructure, thereby having all four foci parallel to the direction of flow. Transport effects of the diffusion as a function of flow and distance could then also be studied. 相似文献
76.
The transportable setup of the Cologne Tuneable Heterodyne Infrared Spectrometer (THIS) is presented. Frequency tuneability over a wide range provided by the use of tuneable diode lasers as local oscillators (LO) allows a variety of molecules in the mid-infrared to be observed. Longtime integration, which is essential for astronomical observations, is possible owing to tight frequency control of the LO with optical feedback from an external cavity. THIS is developed to fly on the Stratospheric Observatory for Infrared Astronomy beginning in 2006 but can also be used on different types of ground-based telescopes. 相似文献
77.
Brennan Penny L.; Schutte Kathleen K.; Moos Rudolf H. 《Canadian Metallurgical Quarterly》2006,13(3):253
At 1 year, 4 years, and 10 years after baseline, late-middle-aged adults reported whether they had successfully resolved their most important stressor of the past year. Compared to individuals who never resolved focal stressors over the 10-year interval, those who always did consistently showed less negative stressor appraisal, less reliance on avoidance coping, and less use of exploratory relative to directed coping responses, independent of type and severity of focal stressor. Less use of exploratory relative to directed coping and having more social resources, fewer health problems, and fewer depressive symptoms at baseline predicted more stressor resolution over the next 10 years. These predictors are promising foci for prospective efforts to optimize ways in which aging adults manage late-life stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
We define three operations on strings and languages suggested by the process of gene assembly in hypotrichous ciliates. This
process is considered to be a prine example of DNA computing in vivo. This paper is devoted to some computational aspects
of these operations from a formal language point of view. The closure of the classes of regular and context-free languages
under these operations is settled. Then, we consider theld-macronuclear language of a given languageL, which consists of allld-macronuclear strings obtained from the strings ofL by iteratively applying the loop-direct repeat-excision. Finally, we discuss some open problems and further directions of
research.
Rudolf Freund: He received his master and doctor degree in computer science from the Vienna University of Technology, Austria, in 1980
and 1982, respectively. In 1986, he received his master degree in mathematics and physics from the University Vienna, Austria.
In 1988 he joined the Vienna University of Technology in Austria, where he became an Associate Professor in September 1995.
He has given various lectures in theoretical computer science, especially on formal languages and automata. His research interests
include array and graph grammars, regulated rewritung, infinite words, syntactic pattern recognition, neural networks, and
especially models and systems for biological computing. In these fields he is author of more than sixty scientific papers.
Carlos Martín-Vide: He is Professor and Head of the Research Group on Mathematical Linguistics at Rovira i Virgili University, Tarragona, Spain.
His specialities are formal language theory and mathematical linguistics. His last volume edited is Where Mathematics, Computer
Science, Linguistics and Biology Meet (Kluwer, 2001, with V. Mitrana). He published 150 papers in conference proceedings and
journals such as: Acta Informatica, BioSystems. Computational Linguistics, Computers and Artificial Intelligence, Information
Processing Letters, Information Sciences, International Journal of Computer Mathematics, New Generation Computing, Publicationes
Mathematicae Debrecen, and Theoretical Computer Science. He is the editor-in-chief of the journal Grammars (Kluwer), and the
chairman of the 1st International PhD School in Formal Languages and Applications (2001–2003).
Victor Mitrana, Ph.D.: He is Professor of Computer Science at the Faculty of Mathematics, University of Bucharest. He received his MSc and PhD
from the University of Bucharest in 1986 and 1993, respectively. In 1999 he was awarded with the “Gheorghe Lazar” Prize for
Mathematics of the Romanian Academy. His research interests include: formal language theory and applications, combinatorics
on words, computational models inspired from biology, mathematical linguistics. In these areas, he published three books,
more than 100 papers, and edited two books. He is an associate editor of “The Korean Journal of Computational and Applied
Mathematics” and an editor of “Journal of Universal Computer Science”. 相似文献
79.
Rudolf F. Stark 《Computer-Aided Civil and Infrastructure Engineering》1992,7(2):161-175
Abstract: A local database manager (LDBM) is presented. It is a software development tool consisting of a set of easy-to-use in-core data management subroutines written in FORTRAN 77. One of the main motivations for the development of this LDBM was to enhance the eflcient use of core memory which seems to be obvious with respect to a PC programming environment. However, even on virtual machines, high performance achieved by minimizing page faults is strongly based on a sophisticated database management system (DBMS). In order to accomplish this objective, the LDBM allows the use of different data types according to the requirements of the actual situation and to the existing programming environment. Integer, short integer, real, double precision, complex, double complex and character data can be handled. Moreover, a two-level hierarchical data structure is used which groups related data in a different and more economic way rather than by means of increasing the number of levels in the DIMENSION statement. Of course, old, no longer used data may be deleted, leaving room for the allocation of new data. Using a technique of 'flexible garbage collection', i.e. the ensuing gap after the deletion of a data block is not automatically closed, the time consumed by the LDBM during a deletion operation is actually not affected by the length of data blocks. 相似文献
80.
T Jiang G Sweeney MT Rudolf A Klip A Traynor-Kaplan RY Tsien 《Canadian Metallurgical Quarterly》1998,273(18):11017-11024
Phosphoinositide 3-OH kinases and their products, D-3 phosphorylated phosphoinositides, are increasingly recognized as crucial elements in many signaling cascades. A reliable means to introduce these lipids into intact cells would be of great value for showing the physiological roles of this pathway and for testing the specificity of pharmacological inhibitors of the kinases. We have stereospecifically synthesized di-C8-PIP3/AM and di-C12-PIP3/AM, the heptakis(acetoxymethyl) esters of dioctanoyl- and dilauroylphosphatidylinositol 3,4,5-trisphosphate, in 14 steps from myo-inositol. The ability of these uncharged lipophilic derivatives to deliver phosphatidylinositol 3,4,5-trisphosphate across cell membranes was demonstrated on 3T3-L1 adipocytes and T84 colon carcinoma monolayers. Insulin stimulation of hexose uptake into adipocytes was inhibited by the kinase inhibitor wortmannin and was largely restored by di-C8-PIP3/AM, which had no effect in the absence of insulin. Thus phosphatidylinositol 3,4,5-trisphosphate or a metabolite was necessary but not sufficient for stimulation of hexose transport. In T84 epithelial monolayers, di-C12-PIP3/AM mimicked epidermal growth factor in inhibiting chloride secretion and potassium efflux, suggesting that phosphatidylinositol 3,4, 5-trisphosphate was sufficient to modulate these fluxes and mediate epidermal growth factor's action. 相似文献