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41.
艾冲 《沈阳工程学院学报(自然科学版)》2015,(1):47-49
针对循环流化床锅炉冷态启动用油量较大的问题,采用两台相邻锅炉一次热风风道联络的方法,实践中利用邻炉一次热风进行锅炉冷态启动,以煤代油缩短锅炉点火投油时间。结果表明:此方法使锅炉冷态启动时的用油量大幅下降,达到了显著的节能效果,并在此基础上展望了一次热风联络技术在锅炉防腐保养、冬季防冻等方面的应用前景。 相似文献
42.
Adel Al Rai Elena Stojanovska Yasin Akgul Mohammad Mansoob Khan Ali Kilic Safak Yilmaz 《应用聚合物科学杂志》2021,138(7):49835
Highly porous free-standing co-poly(vinylidene fluoride)/modacrylic/SiO2 nanofibrous membrane was developed using electrically-assisted solution blow spinning method. The performance and the potential of the membrane as a lithium-ion battery separator were investigated. The addition of modacrylic enhanced the solution spinnability that resulted in defect-free membranes. Moreover, the presence of modacrylic enhanced the dimensional and thermal stabilities, while the addition of hydrophilic SiO2 nanoparticle enhanced both mechanical property and ionic conductivity. Combustion test results illustrated that the presence of modacrylic provide flame retarding property over a set of different polymeric-based membranes. Electrochemical performance results showed that the developed membrane can increase the battery capacity compared with the commercial separator. 相似文献
43.
In this paper, the robust input covariance constraint (ICC) control problem with polytopic uncertainty is solved using convex optimization with linear matrix inequality (LMI) approach. The ICC control problem is an optimal control problem that optimizes the output performance subjected to multiple constraints on the input covariance matrices. This control problem has significant practical implications when hard constraints need to be satisfied on control actuators. The contribution of this paper is the characterization of the control synthesis LMIs used to solve the robust ICC control problem for polytopic uncertain systems. Both continuous‐ and discrete‐time systems are considered. Parameter‐dependent and independent Lyapunov functions have been used for robust ICC controller synthesis. Numerical design examples are presented to illustrate the effectiveness of the proposed approach. 相似文献
44.
The game problem of pursuit is studied for dynamic processes evolving under uncertainty and counteraction. The terminal set is supposed to be a cylindrical set-valued mapping. The method of resolving functions is used to establish the sufficient conditions for the game termination in the class of quasi- and stroboscopic strategies for various schemes of the method. The guaranteed times are compared. The results are illustrated using the model with integral control unit and game problems with simple motion. 相似文献
45.
Moftah Elzobi Ayoub Al-Hamadi Zaher Al Aghbari Laslo Dings 《International Journal on Document Analysis and Recognition》2013,16(3):295-308
Even though a lot of researches have been conducted in order to solve the problem of unconstrained handwriting recognition, an effective solution is still a serious challenge. In this article, we address two Arabic handwriting recognition-related issues. Firstly, we present IESK-arDB, a new multi-propose off-line Arabic handwritten database. It is publicly available and contains more than 4,000 word images, each equipped with binary version, thinned version as well as a ground truth information stored in separate XML file. Additionally, it contains around 6,000 character images segmented from the database. A letter frequency analysis showed that the database exhibits letter frequencies similar to that of large corpora of digital text, which proof the database usefulness. Secondly, we proposed a multi-phase segmentation approach that starts by detecting and resolving sub-word overlaps, then hypothesizing a large number of segmentation points that are later reduced by a set of heuristic rules. The proposed approach has been successfully tested on IESK-arDB. The results were very promising, indicating the efficiency of the suggested approach. 相似文献
46.
In this paper, a fuzzy logic controller (FLC) based variable structure control (VSC) is presented. The main objective is to obtain an improved performance of highly non‐linear unstable systems. New functions for chattering reduction and error convergence without sacrificing invariant properties are proposed. The main feature of the proposed method is that the switching function is added as an additional fuzzy variable and will be introduced in the premise part of the fuzzy rules; together with the state variables. In this work, a tuning of the well known weighting parameters approach is proposed to optimize local and global approximation and modelling capability of the Takagi‐Sugeno (T‐S) fuzzy model to improve the choice of the performance index and minimize it. The main problem encountered is that the T‐S identification method can not be applied when the membership functions are overlapped by pairs. This in turn restricts the application of the T‐S method because this type of membership function has been widely used in control applications. The approach developed here can be considered as a generalized version of the T‐S method. An inverted pendulum mounted on a cart is chosen to evaluate the robustness, effectiveness, accuracy and remarkable performance of the proposed estimation approach in comparison with the original T‐S model. Simulation results indicate the potential, simplicity and generality of the estimation method and the robustness of the chattering reduction algorithm. In this paper, we prove that the proposed estimation algorithm converge the very fast, thereby making it very practical to use. The application of the proposed FLC‐VSC shows that both alleviation of chattering and robust performance are achieved. 相似文献
47.
Mark Liffiton Maher Mneimneh Inês Lynce Zaher Andraus João Marques-Silva Karem Sakallah 《Constraints》2009,14(4):415-442
Explaining the causes of infeasibility of Boolean formulas has practical applications in numerous fields, such as artificial
intelligence (repairing inconsistent knowledge bases), formal verification (abstraction refinement and unbounded model checking),
and electronic design (diagnosing and correcting infeasibility). Minimal unsatisfiable subformulas (MUSes) provide useful
insights into the causes of infeasibility. An unsatisfiable formula often has many MUSes. Based on the application domain,
however, MUSes with specific properties might be of interest. In this paper, we tackle the problem of finding a smallest-cardinality
MUS (SMUS) of a given formula. An SMUS provides a succinct explanation of infeasibility and is valuable for applications that
are heavily affected by the size of the explanation. We present (1) a baseline algorithm for finding an SMUS, founded on earlier
work for finding all MUSes, and (2) a new branch-and-bound algorithm called Digger that computes a strong lower bound on the size of an SMUS and splits the problem into more tractable subformulas in a recursive
search tree. Using two benchmark suites, we experimentally compare Digger to the baseline algorithm and to an existing incomplete genetic algorithm approach. Digger is shown to be faster in nearly all cases. It is also able to solve far more instances within a given runtime limit than
either of the other approaches. 相似文献
48.
Mesfer Al Duhayyim Heba G. Mohamed Fadwa Alrowais Fahd N. Al-Wesabi Anwer Mustafa Hilal Abdelwahed Motwakel 《计算机系统科学与工程》2023,46(2):1293-1310
The Internet of Things (IoT) has gained more popularity in research because of its large-scale challenges and implementation. But security was the main concern when witnessing the fast development in its applications and size. It was a dreary task to independently set security systems in every IoT gadget and upgrade them according to the newer threats. Additionally, machine learning (ML) techniques optimally use a colossal volume of data generated by IoT devices. Deep Learning (DL) related systems were modelled for attack detection in IoT. But the current security systems address restricted attacks and can be utilized outdated datasets for evaluations. This study develops an Artificial Algae Optimization Algorithm with Optimal Deep Belief Network (AAA-ODBN) Enabled Ransomware Detection in an IoT environment. The presented AAA-ODBN technique mainly intends to recognize and categorize ransomware in the IoT environment. The presented AAA-ODBN technique follows a three-stage process: feature selection, classification, and parameter tuning. In the first stage, the AAA-ODBN technique uses AAA based feature selection (AAA-FS) technique to elect feature subsets. Secondly, the AAA-ODBN technique employs the DBN model for ransomware detection. At last, the dragonfly algorithm (DFA) is utilized for the hyperparameter tuning of the DBN technique. A sequence of simulations is implemented to demonstrate the improved performance of the AAA-ODBN algorithm. The experimental values indicate the significant outcome of the AAA-ODBN model over other models. 相似文献
49.
Khaled M. Alalayah Fatma S. Alrayes Jaber S. Alzahrani Khadija M. Alaidarous Ibrahim M. Alwayle Heba Mohsen Ibrahim Abdulrab Ahmed Mesfer Al Duhayyim 《计算机系统科学与工程》2023,46(3):3121-3139
With the increased advancements of smart industries, cybersecurity has become a vital growth factor in the success of industrial transformation. The Industrial Internet of Things (IIoT) or Industry 4.0 has revolutionized the concepts of manufacturing and production altogether. In industry 4.0, powerful Intrusion Detection Systems (IDS) play a significant role in ensuring network security. Though various intrusion detection techniques have been developed so far, it is challenging to protect the intricate data of networks. This is because conventional Machine Learning (ML) approaches are inadequate and insufficient to address the demands of dynamic IIoT networks. Further, the existing Deep Learning (DL) can be employed to identify anonymous intrusions. Therefore, the current study proposes a Hunger Games Search Optimization with Deep Learning-Driven Intrusion Detection (HGSODL-ID) model for the IIoT environment. The presented HGSODL-ID model exploits the linear normalization approach to transform the input data into a useful format. The HGSO algorithm is employed for Feature Selection (HGSO-FS) to reduce the curse of dimensionality. Moreover, Sparrow Search Optimization (SSO) is utilized with a Graph Convolutional Network (GCN) to classify and identify intrusions in the network. Finally, the SSO technique is exploited to fine-tune the hyper-parameters involved in the GCN model. The proposed HGSODL-ID model was experimentally validated using a benchmark dataset, and the results confirmed the superiority of the proposed HGSODL-ID method over recent approaches. 相似文献
50.
Abdelhamied A. Ateya Amel Ali Alhussan Hanaa A. Abdallah Mona A. Al duailij Abdukodir Khakimov Ammar Muthanna 《计算机系统科学与工程》2023,45(2):1775-1787
Next-generation cellular networks are expected to provide users with innovative gigabits and terabits per second speeds and achieve ultra-high reliability, availability, and ultra-low latency. The requirements of such networks are the main challenges that can be handled using a range of recent technologies, including multi-access edge computing (MEC), artificial intelligence (AI), millimeter-wave communications (mmWave), and software-defined networking. Many aspects and design challenges associated with the MEC-based 5G/6G networks should be solved to ensure the required quality of service (QoS). This article considers developing a complex MEC structure for fifth and sixth-generation (5G/6G) cellular networks. Furthermore, we propose a seamless migration technique for complex edge computing structures. The developed migration scheme enables services to adapt to the required load on the radio channels. The proposed algorithm is analyzed for various use cases, and a test bench has been developed to emulate the operator’s infrastructure. The obtained results are introduced and discussed. 相似文献