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91.
92.
In today’s smart city transportation, traffic congestion is a vexing issue, and vehicles seeking parking spaces have been identified as one of the causes leading to approximately 40% of traffic congestion. Identifying parking spaces alone is insufficient because an identified available parking space may have been taken by another vehicle when it arrives, resulting in the driver’s frustration and aggravating traffic jams while searching for another parking space. This explains the need to predict the availability of parking spaces. Recently, deep learning (DL) has been shown to facilitate drivers to find parking spaces efficiently, leading to a promising performance enhancement in parking identification and prediction systems. However, no work reviews DL approaches applied to solve parking identification and prediction problems. Inspired by this gap, the purpose of this work is to investigate, highlight, and report on recent advances in DL approaches applied to predict and identify the availability of parking spaces. A taxonomy of DL-based parking identification and prediction systems is established as a methodology by classifying and categorizing existing literature, and by doing so, the salient and supportive features of different DL techniques for providing parking solutions are presented. Moreover, several open research challenges are outlined. This work identifies that there are various DL architectures, datasets, and performance measures used to address parking identification and prediction problems. Moreover, there are some open-source implementations available that can be used directly either to extend existing works or explore a new domain. This is the first short survey article that focuses on the use of DL-based techniques in parking identification and prediction systems for smart cities. This study concludes that although the deployment of DL in parking identification and prediction systems provides various benefits, the convergence of these two types of systems and DL brings about new issues that must be resolved in the near future.  相似文献   
93.
Abstract— Overdrive is commonly used to reduce the liquid‐crystal response time and motion blur in liquid‐crystal displays (LCDs). However, overdrive requires a large frame memory in order to store the previous frame for reference. In this paper, a lapped transform‐based codec (LTC) is proposed to reduce the frame memory needed for LCD overdrive. In the latest literature, a directional prediction‐based codec (DPC) employs eight directional predictions, which takes up a large percentage of the computational complexity of the codec and does not consider the de‐correlation of the inter‐blocks. Therefore, the LTC first uses the lapped transform to decompose the correlation of the inter‐blocks in the YUV color space. A hadamard transform is then used for energy compaction. The reordered coefficients are pre‐quantized and encoded using the proposed adaptive bit‐plane coding (ABPC) method for a simple hardware implementation. The simulation results show that the proposed LTC significantly improves the DPC in both subjective and objective performance and outperforms the block truncation coding (BTC) and adaptive multi‐level BTC (AM‐BTC), which have been described in the literature.  相似文献   
94.
A New Approach for Multi-Document Update Summarization   总被引:1,自引:1,他引:0       下载免费PDF全文
1958(2)
  • Manifold-ranking based topic-focused multi-document summarization 2007
  • An Introduction to Kolmogorov Complexity and Its Applications 1997
  • The use of MMR,diversity-based reranking for reordering documents and producing summaries 1998
  • Centroid-based summarization of multiple documents 2004(6)
  • A trainable document summarizer 1995
  • Impact of linguistic analysis on the semantic graph coverage and learning of document extracts 2005
  • Document summarization using conditional random fields 2007
  • Adasum:An adaptive model for summarization 2008
  • Lexpagerank:Prestige in multidocument text summarization 2004
  • Mihalcea R.Taran P Textrank-Bring order into texts 2004
  • Mihalcea R.Tarau P A language independent algorithm for single and multiple document summarization 2005
  • Wan X.Yang J.Xiao J Towards an iterative reinforcement approach for simultaneous document summarization and keyword extraction 2007
  • Wan X An exploration of document impact on graph-based multi-document summarization 2008
  • Bennett C H.Gács P.Li M.Vitányi P M,Zurek W H Information distance 1998(4)
  • Li M.Badger J H.Chen X.Kwong S,Kearney P,Zhang H An information-based sequence distance and its application to whole mitochondrial genome phylogeny 2001(2)
  • Li M.Chen X.Li X.Ma B Vitányi P M The similarity metric 2004(12)
  • Long C.Zhu X.Li M.Ma B Information shared by many objects 2008
  • Benedetto D.Caglioti E.Loreto V Language trees and zipping 2002(4)
  • Bennett C H.Li M.Ma B Chain letters and evolutionary histories 2003(6)
  • Cilibrasi R L.Vitányi P M The Google similarity distance 2007(3)
  • Zhang X.Hao Y.Zhu X.Li M Information distance from a question to an answer 2007
  • Ziv J.Lempel A A universal algorithm for sequential data compression 1977(3)
  • Lin C Y.Hovy E Automatic evaluation of summaries using n-gram co-occurrence statistics 2003
  • Nenkova A.Passonneau R.Mckeown K The pyramid method:Incorporating human content selection variation in summarization evaluation 2007(2)
  • >>更多...  相似文献   

    95.
    SVC在无线信道传输中的非均衡差错保护   总被引:1,自引:0,他引:1  
    针对H.264的可伸缩视频编码扩展标准(SVC)在噪声信道中的传输,采用低密度奇偶校验码(LDPC)提出一种非均衡差错保护的方案。在所提的方案中,根据时间、分辨率和质量把原视频序列按重要性分成不同的层。由于不同层的数据对错误的敏感性不同,对其进行不同码率的LDPC信道编码,实现非均衡差错保护。根据视频流中每一帧不同层的PSNR增量不同,和不同信道码率下正确解码的概率不同,反复计算每一帧所有码率组合的PSNR增量值并找出最大组,从而进行信道编码并传输。实验表明,在相同的平均码率条件下,提出的方案相比其他方案的PSNR值增加了2.8 dB,更适合无线信道的传输。  相似文献   
    96.
    This paper presents a passive control scheme for a force reflecting bilateral teleoperation system with a varying time communication delay. To improve the stability and performance of the system, the master and slave must be coupled dynamically via a transmission network through which the force and velocity are communicated bilaterally. However, the time delay caused by various factors, such as the transmission distance, network congestion, and communication bandwidth, is a long-standing impediment to bilateral control that can destabilize the system. In this study, we investigated how a varying time delay affects the stability of a teleoperation system. A new optimal adaptive approach based on a passive control scheme was designed bilaterally for both the master and slave sites. Extra variables were transmitted together with the wave variables in the scattering system. The proposed scheme achieved both passive control, and an acceptable tracking performance. The tracking performance was demonstrated using a computer simulation of varying time delays in a bilateral teleoperation system.  相似文献   
    97.
    Support vector machines (SVM) are an emerging data classification technique with many diverse applications. The feature subset selection, along with the parameter setting in the SVM training procedure significantly influences the classification accuracy. In this paper, the asymptotic behaviors of support vector machines are fused with genetic algorithm (GA) and the feature chromosomes are generated, which thereby directs the search of genetic algorithm to the straight line of optimal generalization error in the superparameter space. On this basis, a new approach based on genetic algorithm with feature chromosomes, termed GA with feature chromosomes, is proposed to simultaneously optimize the feature subset and the parameters for SVM.To evaluate the proposed approach, the experiment adopts several real world datasets from the UCI database and from the Benchmark database. Compared with the GA without feature chromosomes, the grid search, and other approaches, the proposed approach not only has higher classification accuracy and smaller feature subsets, but also has fewer processing time.  相似文献   
    98.
    In financial service industry, service improvement should be considered from process viewpoint and customer viewpoint because the value creation is ultimately linked with internal business processes on the back office and customers are involved as a co-producer of value. In this perspective, customer complaints through call centers are adequate to support the analysis for service improvement in financial service industry. In this study, we propose a web-based decision support system for business process management employing customer complaints, namely Voice of the Customer (VOC), and its handling data for service improvement. It involves VOC conversion for data enrichment and includes analysis of summarization, exception and comparison. The proposed system is evaluated on a major credit card company in South Korea.  相似文献   
    99.
    基于遥感的长沙市城市热岛效应时空分析   总被引:1,自引:0,他引:1  
    利用TM/ETM+数据,以长沙市为例,反演了地表温度,并针对不同时相的遥感数据,利用城市热岛强度来反映热岛效应强弱的变化。结果表明,长沙市的热岛空间分布与城市建成区的轮廓相吻合。城市热岛的范围随着城市建设、新建开发区以及道路交通网的发展不断增大,且在东南方向为主要增长方向。根据热岛强度鉴别并提取了强热岛区与正常区,发现长沙市强热岛区的面积已经从1993年的13.18km2扩大至2008年的68.16km2。最后,对长沙市热岛未来的发展趋势进行了预测。  相似文献   
    100.
    This paper presents the design and control of a novel assistive robotic walker that we call “JAIST active robotic walker (JARoW)”. JARoW is developed to provide potential users with sufficient ambulatory capability in an efficient, cost-effective way. Specifically, our focus is placed on how to allow easier maneuverability by creating a natural interface between the user and JARoW. For the purpose, we develop a rotating infrared sensor to detect the user’s lower limb movement. The implementation details of the JARoW control algorithms based on the sensor measurements are explained, and the effectiveness of the proposed algorithms is verified through experiments. Our results confirmed that JARoW can autonomously adjust its motion direction and velocity according to the user’s walking behavior without requiring any additional user effort.  相似文献   
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