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1.
Both planning and design phase of large infrastructural project require analysis, modelling, visualization, and numerical analysis. To perform these tasks, different tools such as Building Information Modelling (BIM) and numerical analysis software are commonly employed. However, in current tunnel engineering practice, there are no systematic solutions for the exchange between design and analysis models, and these tasks usually involve manual and error-prone model generation, setup and update. In this paper, focussing on tunnelling engineering, we demonstrate a systematic and versatile approach to efficiently generate a tunnel design and analyse the lining in different practical scenarios. To this end, a BIM-based approach is developed, which connects a user-friendly industry-standard BIM software with effective simulation tools for high-performance computing. A fully automatized design-through-analysis workflow solution for segmented tunnel lining is developed based on a fully parametric design model and an isogeometric analysis software, connected through an interface implemented with a Revit plugin. The IGA-Revit interface implements a reconstruction algorithm based on sweeping teachnique to construct trivariate NURBS lining segment geometry, which avoids the burden to deal with trimmed geometries. 相似文献
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Workflow management technologies have been dramatically improving their deployment architectures and systems along with the evolution and proliferation of cloud distributed computing environments. Especially, such cloud computing environments ought to be providing a suitable distributed computing paradigm to deploy very large-scale workflow processes and applications with scalable on-demand services. In this paper, we focus on the distribution paradigm and its deployment formalism for such very large-scale workflow applications being deployed and enacted across the multiple and heterogeneous cloud computing environments. We propose a formal approach to vertically as well as horizontally fragment very large-scale workflow processes and their applications and to deploy the workflow process and application fragments over three types of cloud deployment models and architectures. To concretize the formal approach, we firstly devise a series of operational situations fragmenting into cloud workflow process and application components and deploying onto three different types of cloud deployment models and architectures. These concrete approaches are called the deployment-driven fragmentation mechanism to be applied to such very large-scale workflow process and applications as an implementing component for cloud workflow management systems. Finally, we strongly believe that our approach with the fragmentation formalisms becomes a theoretical basis of designing and implementing very large-scale and maximally distributed workflow processes and applications to be deployed on cloud deployment models and architectural computing environments as well. 相似文献
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Knitted composites are textile composite materials that consist of knitted textile reinforcement and polymer matrix. Knitted composites exhibit great design flexibility by allowing the customization of shapes, textures, and material properties. These features facilitate the optimization of buildings’ material systems and the creation of buildings with light weight and high material efficiency.To achieve such a lightweight, material-efficient building structure with knitted composites, this research investigates the material properties of knitted composites and proposes a design process for building-scale knitted composite systems. In the material study, this research examines certain mechanical properties of the material and the effects of additional design elements. In the design exploration, this research explores the design workflow of the structural form, element arrangement, and knit distribution of the material system at the macro-, meso-, and microscales. The project of MeiTing serves as proof of the concept and the design workflow. 相似文献
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图像可逆信息隐藏作为信息隐藏的重要分支,发展至今已近三十年,因其独有的图像无损恢复能力,一直备受医学、司法、军事等重点领域的青睐。然而现有可逆信息隐藏研究成果繁多,迁移知识广泛,本文简要梳理可逆信息隐藏的发展脉络,在回顾经典算法的基础上,加以简化、注释,总结成功经验,展望潜在应用,以期为研究者提供一个按图索骥的探索路径。本文主要包括3个部分,分别为位图(Bitmap,BMP)图像的可逆信息隐藏(适用于空域嵌入操作)、JPEG (Joint Photographic Experts Group)图像的可逆信息隐藏(适用于频域和编码域嵌入操作)和鲁棒可逆水印(适用于扩展性研究)。通过近百篇高影响力文献的梳理可知,可逆研究的受众广泛、基础深厚,其严谨的数学定义和简明的机理论证是深受研究者推崇和坚持的重要原因。“干净、简明”的特点也是其能够与现实应用有效结合的强力抓手。增加可逆算法对于载体多样性的普适性研究,引入新的评价指标来导引算法与现实应用的融合,将是未来可开拓的方向。可逆信息隐藏技术能够恢复图像初始状态,其独特之处在于图像本身就是一个复杂语义的信息表达。这既要求可逆嵌入操作所施加的影响不能改变图像所表达的主要语义,又要求该操作是可消除的,保留溯源能力,将内容的信息表达权始终交由图像本身。这一特点不仅为敏感领域信息处理所亟需,也是其他常见领域并不排斥的。严格来说,一定程度上的复原本就是事物发展到一定阶段后的必然追求。据此,本文认为推广可逆研究与多学科融合解决更难、更广泛的问题,实现长远发展,是完全必要且可行的。 相似文献
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2002年全国暖通空调制冷学术年会综述 总被引:13,自引:2,他引:13
综述了年会盛况,着重报道了有关供热计量收费、用于分户热计量的设计技术方法、不同供热方式,室内空气品质、新风量、置换通风、防排烟,热泵应用、户式中央空调、冰蓄冷与低温送风等热点问题在17个专题讨论会上得出的主要意见。 相似文献
7.
JingLanru FengXiating 《岩石力学与工程学报》2003,22(10):1704-1715
The coupled thermo-hydro-mechanical and chemical (THMC) processes of stress/deformation, fluid flow, temperature and geochemical reactions of the geological media, namely fractured rocks and soils, play an important role in design, construction,operation and environmental impact assessments of rock and soil engineering works such as underground nuclear waste repositories,oil/gas production and storage, geothermal energy extraction, landslides and slope stability, hydropower and water conservancy complexes, etc. This paper presents an overview of the international and Chinese experiences in numerical modeling of the coupled THMC processes for both the state-of-the-knowledge, remaining challenges and vossible future vrosvects. 相似文献
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作为一种兼顾环保、节能的制冷剂,R290与R22的标准沸点、凝固点、临界点等基本物理性质非常接近,具备替代R22的基本条件,拥有广阔的应用前景和市场价值。但由于其与空气混合能形成易燃易爆混合物,存在重大安全隐患,抑制了R290制冷产品的推广和应用。本文通过总结国内外学者对改善R290制冷系统所做的研究,分析了R290替代R22存在的弊端,对提高R290系统安全性的解决方案进行综述,并根据最新研究,分别从减少制冷剂灌注量、间接使用R290以及加入阻燃剂方面对今后的研究方向作出展望,以期推广R290在制冷产品中的使用。 相似文献
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Irene Vanni Simona Coco Anna Truini Marta Rusmini Maria Giovanna Dal Bello Angela Alama Barbara Banelli Marco Mora Erika Rijavec Giulia Barletta Carlo Genova Federica Biello Claudia Maggioni Francesco Grossi 《International journal of molecular sciences》2015,16(12):28765-28782
Next-generation sequencing (NGS) is a cost-effective technology capable of screening several genes simultaneously; however, its application in a clinical context requires an established workflow to acquire reliable sequencing results. Here, we report an optimized NGS workflow analyzing 22 lung cancer-related genes to sequence critical samples such as DNA from formalin-fixed paraffin-embedded (FFPE) blocks and circulating free DNA (cfDNA). Snap frozen and matched FFPE gDNA from 12 non-small cell lung cancer (NSCLC) patients, whose gDNA fragmentation status was previously evaluated using a multiplex PCR-based quality control, were successfully sequenced with Ion Torrent PGM™. The robust bioinformatic pipeline allowed us to correctly call both Single Nucleotide Variants (SNVs) and indels with a detection limit of 5%, achieving 100% specificity and 96% sensitivity. This workflow was also validated in 13 FFPE NSCLC biopsies. Furthermore, a specific protocol for low input gDNA capable of producing good sequencing data with high coverage, high uniformity, and a low error rate was also optimized. In conclusion, we demonstrate the feasibility of obtaining gDNA from FFPE samples suitable for NGS by performing appropriate quality controls. The optimized workflow, capable of screening low input gDNA, highlights NGS as a potential tool in the detection, disease monitoring, and treatment of NSCLC. 相似文献