共查询到20条相似文献，搜索用时 202 毫秒
1.
郑欣欣 《内蒙古科技与经济》2018,(13)
介绍了基于二部图的个性化推荐算法,探讨了近年来对该算法局限性的各种改进思路,主要有结合优化算法的改进、资源流转加权、冷启动问题的处理等方面,期望通过进一步深入研究提高二部图网络算法个性化推荐的质量。 相似文献
2.
基于变长Turbo码的联合信源信道译码通过构造联合译码平面网格图,具有比比特级译码更好的性能.但平面网格图复杂,使变长Turbo码译码复杂度高.基于此,构造了一个空间网格图,提出基于变长Turbo码的低复杂度联合信源信道译码方法.仿真结果表明,该算法比平面网格图计算复杂度减少约3.8%,在SER(symbol error ratio)为10-4时,获得Eb/N0增益约为0.2dB. 相似文献
3.
本文运用因子图,对现在的军事通信方法中伪码捕获算法的高效迭代算法进行改进,将算法与AES和最新的加密算法基于信息论方法的绝密通信理论进行结合使其成功应用于军事通信中,对提高通信可靠性具有重要意义。 相似文献
4.
引入矢量量化器码书的特征变量，提出基于结构化码书的两级波形矢量量化器设计新算法。算法包括：合理构造初始码书、快速训练码书、快速量化输入矢量。通过计算机对语音信号矢量量化的模拟，结果表明新算法明显地缩短了复杂度和提高了矢量量化的速度。 相似文献
5.
本文针对传统的频率-码相位二维串行搜索捕获方法计算量大、且捕获时间长的缺点提出基于FFT的频域并行捕获PN码算法。该并行算法对频率搜索方法进行了改进,并提出了一种消除数据调制的方法。理论分析和仿真结果表明该方法能实现低信噪比、高动态性条件下PN码的快速捕获。 相似文献
6.
段文秀 《内蒙古科技与经济》2011,(24):78-79
给出了一个基于布尔矩阵的单属性依赖集候选码求解算法,该算法不用考虑N类属性、回路、子图等问题,能够非常容易的在计算机上编程实现,能十分有效地求出指定问题域中的所有候选码。同时,该算法也为复合属性依赖集的候选码求解方法提供了良好的基础。 相似文献
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8.
为了得到带有异常处理结构的切片,文章从传统控制流图到系统依赖图进行了层层改进,给出了构造系统依赖图的算法,并以此为基础得到精确的程序切片。该方法可以处理因为异常结构而引起的数据流和控制流的变化,有助于实现基于异常传播的程序依赖性分析的自动处理。 相似文献
9.
提出基于图的半监督学习算法,即类别传播算,结合K均值算法改进,用于网页分类。该K均值类别传播方法使用欧式距离的建立带权∈NN图。在这个图中,图节点表示已标记或未标记的网页,边上的权重表示节点的相似度,已标记节点的类别沿着边向邻居节点传播,从而将网页分类问题形式化为类别在图上的传播。结合K均值方法,提高了计算速度以及图方法的归纳能力,经UCI数据集测试,结果表明,此算法比类别传播算法有更好的性能,能够有效地用于半监督网页分类。 相似文献
10.
传统的自组织神经网络系统进行图像量化处理和编码中,算法对于码书初始值选择具有较强的敏感性,从而导致该量化编码算法对训练序列具有较大的依赖性。为此提出基于自组织神经映射网络系统的低失真敏感测量度图像编码图像量化编码方案,主要是针对初始码书的较强敏感性而改进的,以便改进码书的性能和训练效率。改进的方法中通过设置一个响应的频率计数器。由失真的敏感参数对失真测度进行调整,有效降低失真程度,从而减少了已被用作响应码氏的码氏再度成为响应码氏的概率,实现了对码书性能和数量之间的矛盾进行有效地平衡折中。训练效果和仿真结果表明,方法改进效果明显,其峰值信噪比相比提高了3.75 dB,图像还原效果真实有效,能有效适用于对图像向量量化和编码。 相似文献
11.
本文首先阐述了对分网络算法在社会化推荐中的应用,然后分析了社会化推荐的运作机理,构建了社会化推荐模型,最后从相似用户集构建、基于对分网络的用户偏好预测和算法评价3个方面,进行了基于对分网络的用户偏好预测实现研究。评价表明对分网络方法对用户偏好预测的效果较好。 相似文献
12.
《Journal of The Franklin Institute》2019,356(12):6591-6609
This paper investigates the bipartite leader-following consensus of second-order multi-agent systems with signed digraph topology. To significantly reduce the communication burden, an event-triggered control algorithm is proposed to solve the bipartite leader-following consensus problem, where a novel event-triggered function is designed. Under some mild assumptions on the network topology and node dynamics, a sufficient condition is derived using Lyapunov stability method and matrix theory to guarantee the bipartite consensus. In particular, it is shown that the continuous communication can be avoided and the Zeno-behavior can be excluded for the designed event-triggered algorithm. Numerical simulations are presented to illustrate the correctness of the theoretical analysis. 相似文献
13.
Fixed-time bipartite consensus of nonlinear multi-agent systems using event-triggered control design
《Journal of The Franklin Institute》2021,358(17):9178-9198
This paper focuses on designing a leader-following event-triggered control scheme for a category of multi-agent systems with nonlinear dynamics and signed graph topology. First, an event-triggered controller is proposed for each agent to achieve fixed-time bipartite consensus. Then, it is shown that the Zeno-behavior is rejected in the proposed algorithm. To avoid intensive chattering due to the discontinuous controller, the control protocol is improved by estimating the sign function. Moreover, a triggering function is proposed which avoids continuous communication in the event-based strategy. Finally, numerical simulations are given to show the accuracy of the theoretical results. 相似文献
14.
Though many compression methods are based on the use of variable length codes, there has recently been a trend to search for alternatives in which the lengths of the codewords are more restricted, which can have useful applications, such as easier processing and fast decoding. This paper explores the construction of variable-to-fixed length codes, which have been suggested long ago by Tunstall. Using new heuristics based on suffix trees, the performance of Tunstall codes can in some cases be improved by more than 40%. 相似文献
15.
The ability to ensure the desired performance of the cooperative-antagonistic multi-agent networks (MANs) in the presence of communication constraints is an important task in many applications of real systems. In this paper, under the proposed event-triggered condition (ETC), different types of consensus are obtained under different network topology. We concentrates on the event-based bipartite consensus. It is shown that under the proposed ETC (i) the addressed cooperative-antagonistic network with arbitrary communication delays reaches bipartite consensus provided that the network is balanced; (ii) the network model reaches zero if the network is unbalanced. Further, to avoid the continuously verifying the triggering condition, a self-triggered algorithm is proposed for realizing the bipartite consensus of the network model. A numerical example is given to illustrate the effectiveness of the theoretical results. 相似文献
16.
《Information processing & management》2022,59(3):102919
Similarity search with hashing has become one of the fundamental research topics in computer vision and multimedia. The current researches on semantic-preserving hashing mainly focus on exploring the semantic similarities between pointwise or pairwise samples in the visual space to generate discriminative hash codes. However, such learning schemes fail to explore the intrinsic latent features embedded in the high-dimensional feature space and they are difficult to capture the underlying topological structure of data, yielding low-quality hash codes for image retrieval. In this paper, we propose an ordinal-preserving latent graph hashing (OLGH) method, which derives the objective hash codes from the latent space and preserves the high-order locally topological structure of data into the learned hash codes. Specifically, we conceive a triplet constrained topology-preserving loss to uncover the ordinal-inferred local features in binary representation learning. By virtue of this, the learning system can implicitly capture the high-order similarities among samples during the feature learning process. Moreover, the well-designed latent subspace learning is built to acquire the noise-free latent features based on the sparse constrained supervised learning. As such, the latent under-explored characteristics of data are fully employed in subspace construction. Furthermore, the latent ordinal graph hashing is formulated by jointly exploiting latent space construction and ordinal graph learning. An efficient optimization algorithm is developed to solve the resulting problem to achieve the optimal solution. Extensive experiments conducted on diverse datasets show the effectiveness and superiority of the proposed method when compared to some advanced learning to hash algorithms for fast image retrieval. The source codes of this paper are available at https://github.com/DarrenZZhang/OLGH . 相似文献
17.
The leaderless, prescribed performance consensus problem for groups of agents with antagonistic interactions is addressed for the first time in this paper. We consider agents modeled by pure feedback nonlinear systems with unknown dynamics and an agent communication network described by a signed digraph with a directed spanning tree. A new proportional and integral (PI) variable transformation is proposed that enables the solution of the problem of leaderless bipartite consensus with prescribed performance by recasting it into a regulation problem with prescribed performance, which in turn we solve by a low complexity distributed control law. The algorithm guarantees uniform boundedness of all closed-loop signals and prescribed performance for the bipartite consensus error. Simulations verify the validity of our theoretical analysis. 相似文献
18.
主要研究基于VHDL的可编程逻辑器件虚拟实验平台的设计和实现方案。平台的主体是VHDL程序翻译模块和模拟调度模块。翻译模块的核心是VHDL编译器,它将用户编写的VHDL源程序翻译转换为等价的C++语言描述,最终生成若干C++程序文件;模拟调度模块通过改进传统的事件驱动模拟算法,对翻译模块得到的C++文件进行编译、连接和动态调度,实现对所描述的静态电路的动态行为的模拟。通过典型实验样例对平台进行了验证,结果表明该系统中进行实验的过程和结果与真实实验一致,达到预定设计要求。 相似文献
19.
《Information processing & management》2023,60(2):103255
In-depth exploration of the knowledge linkages between science and technology (S&T) is an essential prerequisite for accurately understanding the S&T innovation laws, promoting the transformation of scientific outcomes, and optimizing S&T innovation policies. A novel deep learning-based methodology is proposed to investigate S&T linkages, where papers and patents are applied to represent science and technology. In order to accurately and comprehensively reveal the linkages between science and technology topics, the proposed framework combines the information of knowledge structure with textual semantics. Furthermore, the exploration analysis is also conducted from the perspective of realizing the optimal matching between science and technology topics, which can realize combinatorial optimization of the S&T knowledge systems. Specifically, science and technology networks are constructed based on Node2Vec and BERT. Then, science and technology topics are identified based on the Fast Unfolding algorithm and Z-Score index. Finally, a science-technology bipartite graph is constructed, the S&T topic linkages identification task is successfully transferred into a bipartite matching problem, and the maximum-weight matching is identified using a Kuhn-Munkres bipartite algorithm. An experiment on natural language processing demonstrates the feasibility and reliability of the proposed methodology. 相似文献
20.
《Journal of The Franklin Institute》2023,360(2):1327-1343
This paper is concerned with the secure bipartite consensus of second-order multi-agent systems under denial-of-service (DoS) attacks. The communication network is an antagonistic network, in which there is cooperative or competitive relationship between neighboring agents. Meanwhile, information cannot be transmitted when the system is attacked. A novel event-triggered control algorithm based on sampled data is proposed to save limited resources and exclude the Zeno behavior. By applying the convergence of monotone sequences, graph theory as well as the discrete-time Lyapunov function method, some sufficient conditions on threshold parameters, frequency and duration of DoS attacks, and sampling period are derived to ensure the bipartite consensus under DoS attacks. Finally, the correctness and advantages of theoretical results are demonstrated by a numerical simulation. 相似文献