全文获取类型
收费全文 | 2840篇 |
免费 | 180篇 |
国内免费 | 8篇 |
专业分类
电工技术 | 27篇 |
综合类 | 2篇 |
化学工业 | 656篇 |
金属工艺 | 76篇 |
机械仪表 | 47篇 |
建筑科学 | 103篇 |
矿业工程 | 2篇 |
能源动力 | 94篇 |
轻工业 | 314篇 |
水利工程 | 11篇 |
石油天然气 | 5篇 |
无线电 | 257篇 |
一般工业技术 | 519篇 |
冶金工业 | 340篇 |
原子能技术 | 42篇 |
自动化技术 | 533篇 |
出版年
2023年 | 22篇 |
2022年 | 50篇 |
2021年 | 79篇 |
2020年 | 54篇 |
2019年 | 50篇 |
2018年 | 73篇 |
2017年 | 80篇 |
2016年 | 77篇 |
2015年 | 90篇 |
2014年 | 120篇 |
2013年 | 217篇 |
2012年 | 170篇 |
2011年 | 241篇 |
2010年 | 167篇 |
2009年 | 162篇 |
2008年 | 152篇 |
2007年 | 115篇 |
2006年 | 109篇 |
2005年 | 112篇 |
2004年 | 76篇 |
2003年 | 87篇 |
2002年 | 63篇 |
2001年 | 34篇 |
2000年 | 34篇 |
1999年 | 43篇 |
1998年 | 108篇 |
1997年 | 59篇 |
1996年 | 64篇 |
1995年 | 27篇 |
1994年 | 36篇 |
1993年 | 33篇 |
1992年 | 17篇 |
1991年 | 12篇 |
1990年 | 10篇 |
1989年 | 12篇 |
1987年 | 10篇 |
1986年 | 8篇 |
1985年 | 19篇 |
1984年 | 14篇 |
1983年 | 17篇 |
1982年 | 13篇 |
1981年 | 6篇 |
1980年 | 8篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1977年 | 14篇 |
1976年 | 17篇 |
1975年 | 4篇 |
1974年 | 8篇 |
1973年 | 4篇 |
排序方式: 共有3028条查询结果,搜索用时 31 毫秒
71.
Pierre-Etienne Moreau Christophe Ringeissen Marian Vittek 《Electronic Notes in Theoretical Computer Science》2001,44(2)
Implementation of a rule-based transformation engine consists of several tasks with various abstraction levels. We present a new tool called mtom for the efficient implementation of rule-based transformations. This engine should help to bridge the gap between rewriting implementations and practical applications. It aims at implementing well-identified parts of complex applications where the use of rewriting is natural or crucial. These parts are specified using rewrite rules and integrated with the rest of the application, which is kept in a classical imperative language such as C, C++ or Java. Our tool, which can be viewed as a Yacc-like pre-processor, does not depend on a given term representation, rather it accepts implementation of terms (or term like data-types) of yet existing applications and it permits to define and execute rewrite rules upon those types. From our experiences, this system is well-suited for industrial use as well as for implementations of rule-based languages. The paper introduces several features supported by mtom. 相似文献
72.
Johan Montagnat Ákos Frohner Daniel Jouvenot Christophe Pera Peter Kunszt Birger Koblitz Nuno Santos Charles Loomis Romain Texier Diane Lingrand Patrick Guio Ricardo Brito Da Rocha Antonio Sobreira de Almeida Zoltán Farkas 《Journal of Grid Computing》2008,6(1):45-59
The medical community is producing and manipulating a tremendous volume of digital data for which computerized archiving,
processing and analysis is needed. Grid infrastructures are promising for dealing with challenges arising in computerized
medicine but the manipulation of medical data on such infrastructures faces both the problem of interconnecting medical information
systems to Grid middlewares and of preserving patients’ privacy in a wide and distributed multi-user system. These constraints
are often limiting the use of Grids for manipulating sensitive medical data. This paper describes our design of a medical
data management system taking advantage of the advanced gLite data management services, developed in the context of the EGEE
project, to fulfill the stringent needs of the medical community. It ensures medical data protection through strict data access
control, anonymization and encryption. The multi-level access control provides the flexibility needed for implementing complex
medical use-cases. Data anonymization prevents the exposure of most sensitive data to unauthorized users, and data encryption
guarantees data protection even when it is stored at remote sites. Moreover, the developed prototype provides a Grid storage
resource manager (SRM) interface to standard medical DICOM servers thereby enabling transparent access to medical data without
interfering with medical practice. 相似文献
73.
Nawal Guermouche Olivier Perrin Christophe Ringeissen 《Electronic Notes in Theoretical Computer Science》2008,200(3):155
Web services are becoming one of the main technologies for designing and building complex inter-enterprise business applications. Usually, a business application cannot be fulfilled by one Web service but by coordinating a set of them. In particular, to perform a coordination, one of the important investigations is the compatibility analysis. Two Web services are said compatible if they can interact correctly. In the literature, the proposed frameworks for the services compatibility checking rely on the supported sequences of messages. The interaction of services depends also on other properties, such that the exchanged data flow. Thus, considering only supported sequences of messages seems to be insufficient. Other properties on which the services interaction can rely on, are the temporal constraints. In this paper, we focus our interest on the compatibility analysis of Web services regarding their (1) supported sequences of messages, (2) the exchanged data flow, (3) constraints related to the exchanged data flow and (4) the temporal requirements. Based on these properties, we study three compatibility classes: (i) absolute compatibility, (ii) likely compatibility and (iii) absolute incompatibility. 相似文献
74.
Eiman Kanjo Steve Benford Mark Paxton Alan Chamberlain Danae Stanton Fraser Dawn Woodgate David Crellin Adrain Woolard 《Personal and Ubiquitous Computing》2008,12(8):599-607
Mobile sensing and mapping applications are becoming more prevalent because sensing hardware is becoming more portable and
more affordable. However, most of the hardware uses small numbers of fixed sensors that report and share multiple sets of
environmental data which raises privacy concerns. Instead, these systems can be decentralized and managed by individuals in
their public and private spaces. This paper describes a robust system called MobGeoSens which enables individuals to monitor
their local environment (e.g. pollution and temperature) and their private spaces (e.g. activities and health) by using mobile
phones in their day to day life. The MobGeoSen is a combination of software components that facilitates the phone’s internal
sensing devices (e.g. microphone and camera) and external wireless sensors (e.g. data loggers and GPS receivers) for data
collection. It also adds a new dimension of spatial localization to the data collection process and provides the user with
both textual and spatial cartographic displays. While collecting the data, individuals can interactively add annotations and
photos which are automatically added and integrated in the visualization file/log. This makes it easy to visualize the data,
photos and annotations on a spatial and temporal visualization tool. In addition, the paper will present ways in which mobile
phones can be used as noise sensors using an on-device microphone. Finally, we present our experiences with school children
using the above mentioned system to measure their exposure to environmental pollution.
相似文献
Adrain WoolardEmail: |
75.
Lamarque M Tastet C Poncet J Demettre E Jouin P Vial H Dubremetz JF 《Proteomics. Clinical applications》2008,2(9):1361-1374
The Plasmodium falciparum food vacuole (FV) is a lysosome-like organelle where erythrocyte hemoglobin digestion occurs. It is a favorite target in the development of antimalarials. We have used a tandem mass spectrometry approach to investigate the proteome of an FV-enriched fraction and identified 116 proteins. The electron microscopy analysis and the Western blot data showed that the major component of the fraction was the FV and, as expected, the majority of previously known FV markers were recovered. Of particular interest, several proteins involved in vesicle-mediated trafficking were identified, which are likely to play a key role in FV biogenesis and/or FV protein trafficking. Recovery of parasite surface proteins lends support to the cytostomal pathway of hemoglobin ingestion as a FV trafficking route. We have identified 32 proteins described as hypothetical in the databases. This insight into FV protein content provides new clues towards understanding the biological function of this organelle in P. falciparum. 相似文献
76.
Christophe Prieur 《Mathematics of Control, Signals, and Systems (MCSS)》2001,14(2):143-172
We consider control systems for which we know two stabilizing controllers. One is globally asymptotically stabilizing, the
other one is only locally asymptotically stabilizing but for some reason we insist on using it in a neighborhood of the origin.
We look for a uniting control law being equal to the local feedback on a neighborhood of the origin, equal to the global one
outside of a larger neighborhood and being a globally stabilizing controller. We study several solutions based on continuous,
discontinuous, hybrid, time-varying controllers. One criterion of the selection of a controller is the robustness of the stability
to vanishing noise. This leads us in particular to consider a kind of generalization of Krasovskii trajectories for hybrid
systems.
Date received: November 29, 1999. Date revised: August 7, 2000. 相似文献
77.
78.
79.
Granular neural networks for numerical-linguistic data fusion andknowledge discovery 总被引:1,自引:0,他引:1
Yan-Qing Zhang Fraser M.D. Gagliano R.A. Kandel A. 《Neural Networks, IEEE Transactions on》2000,11(3):658-667
We present a neural-networks-based knowledge discovery and data mining (KDDM) methodology based on granular computing, neural computing, fuzzy computing, linguistic computing, and pattern recognition. The major issues include 1) how to make neural networks process both numerical and linguistic data in a database, 2) how to convert fuzzy linguistic data into related numerical features, 3) how to use neural networks to do numerical-linguistic data fusion, 4) how to use neural networks to discover granular knowledge from numerical-linguistic databases, and 5) how to use discovered granular knowledge to predict missing data. In order to answer the above concerns, a granular neural network (GNN) is designed to deal with numerical-linguistic data fusion and granular knowledge discovery in numerical-linguistic databases. From a data granulation point of view the GNN can process granular data in a database. From a data fusion point of view, the GNN makes decisions based on different kinds of granular data. From a KDDM point of view the GNN is able to learn internal granular relations between numerical-linguistic inputs and outputs, and predict new relations in a database. The GNN is also capable of greatly compressing low-level granular data to high-level granular knowledge with some compression error and a data compression rate. To do KDDM in huge databases, parallel GNN and distributed GNN will be investigated in the future. 相似文献
80.
Soham Uday Mehta Ravi Ramamoorthi Mark Meyer Christophe Hery 《Computer Graphics Forum》2012,31(4):1501-1508
Environment‐mapped rendering of Lambertian isotropic surfaces is common, and a popular technique is to use a quadratic spherical harmonic expansion. This compact irradiance map representation is widely adopted in interactive applications like video games. However, many materials are anisotropic, and shading is determined by the local tangent direction, rather than the surface normal. Even for visualization and illustration, it is increasingly common to define a tangent vector field, and use anisotropic shading. In this paper, we extend spherical harmonic irradiance maps to anisotropic surfaces, replacing Lambertian reflectance with the diffuse term of the popular Kajiya‐Kay model. We show that there is a direct analogy, with the surface normal replaced by the tangent. Our main contribution is an analytic formula for the diffuse Kajiya‐Kay BRDF in terms of spherical harmonics; this derivation is more complicated than for the standard diffuse lobe. We show that the terms decay even more rapidly than for Lambertian reflectance, going as l–3, where l is the spherical harmonic order, and with only 6 terms (l = 0 and l = 2) capturing 99.8% of the energy. Existing code for irradiance environment maps can be trivially adapted for real‐time rendering with tangent irradiance maps. We also demonstrate an application to offline rendering of the diffuse component of fibers, using our formula as a control variate for Monte Carlo sampling. 相似文献