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1.
Regarding the recent information technology improvement, the fog computing (FC) emergence increases the ability of computational equipment and supplies modern solutions for traditional industrial applications. In the fog environment, Internet of Things (IoT) applications are completed by computing nodes that are intermediate in the fog, and the physical servers in data centers of the cloud. From the other side, because of resource constraints, dynamic nature, resource heterogeneity, and volatility of fog environment, resource management problems must be considered as one of the challenging issues of fog. The resource managing problem is an NP‐hard issue, so, in the current article, a powerful hybrid algorithm for managing resources in FC‐based IoT is proposed using an ant colony optimization (ACO) and a genetic algorithm (GA). GAs are computationally costly because of some problems such as the lack of guarantee for obtaining optimal solutions. Then, the precision and speed of convergence can be optimized by the ACO algorithm. Therefore, the powerful affirmative feedback pros of ACO on the convergence rate is considered. The algorithm uses GA's universal investigation power, and then it is transformed into ACO primary pheromone. This algorithm outperforms ACO and GA under equal conditions, as the simulation experiments showed.  相似文献   

2.
一种基于蚁群优化的显著边缘检测算法   总被引:2,自引:0,他引:2  
该文提出一种基于蚁群优化的显著边缘检测算法。该算法利用相位编组方法计算支持区面积作为描述图像边缘梯度方向一致性的指标,将梯度幅度和支持区面积结合起来形成启发信息和信息素增量的计算方法,采用线性加权方法将信息素、梯度幅度、支持区面积3种信息综合起来得到蚂蚁转移概率,通过引入禁忌表增大蚂蚁的活动范围。实验结果表明:该文提出的算法能够有效检测图像中的显著边缘特征,对多类图像都有良好的适应性,而且收敛速度较快。  相似文献   

3.
廖伟志  夏小云  贾小军 《电子学报》2020,48(7):1330-1342
为了提高多路径覆盖测试数据的生成效率,研究了一种基于蚁群算法的多路径覆盖测试数据生成方法.首先给出蚁群算法的一种改进方法,该算法以蚂蚁对生成测试数据的重要性作为蚂蚁状态转移和蚂蚁路径变异的依据,以引导更多蚂蚁穿越小概率节点,提高测试数据生成效率.其次,根据改进的蚁群算法分别提出了基于单信息素表和多信息素表的多路径覆盖测试数据生成方法.在基于多信息素表的方法中,每条目标路径的信息素表均被用于其它路径测试数据的求解,而且蚁群算法运行一次即可求解多条目标路径的覆盖测试数据.最后对所提出方法的有效性和复杂度进行了理论分析.实验结果表明,与其它方法相比,基于多信息素表的测试数据生成方法能够有效地生成多路径覆盖测试数据.  相似文献   

4.
Ant colony optimization (ACO) is typically used to search paths through graphs. The concept is based on simulating the behavior of ants in finding paths from the colony to food. Its searching mechanism is applicable for optimizing electric circuits with components, like resistors and capacitors, available in discrete values. However, power electronic circuits (PECs) generally consist of components, like inductors, manufactured in continuous values. Therefore, the traditional ACO algorithm cannot be applied directly. In this paper, an extended ACO (eACO) that can search the optimal values of components manufactured in discrete and continuous values is presented. The idea is based on using the orthogonal design method (ODM) to dynamically update the database of the components available with continuous values, so that these components will have pseudo-discrete values in the search space. To speed up the optimization process, the ODM performs local search of the best combination around the best ant. The eACO also takes the component tolerances into account in evaluating the fitness value of each ant. The proposed algorithm has been successfully used to optimize the design of a buck regulator. The predicted results have been compared with the published results available in the literature and verified with experimental measurements.   相似文献   

5.
基于信息素扩散的蚁群算法   总被引:41,自引:1,他引:41       下载免费PDF全文
蚁群算法是一种新型的搜索算法,其模拟的是蚁群依赖信息素进行通信而表现出的社会性行为.在基本蚁群算法中,蚂蚁之间协作不足,存在滞后的缺陷.本文在分析这一算法的基础上,提出了一种新的更加忠实了真实蚁群信息系统的蚁群算法.该算法通过建立信息素扩散模型,使相距较近的蚂蚁之间能更好地进行协作.TSP问题的仿真结果表明了该算法的有效性.  相似文献   

6.
Eyes are important organs-at-risk (OARs) that should be protected during the radiation treatment of those head tumors. Correct delineation of the eyes on CT images is one of important issues for treatment planning to protect the eyes as much as possible. In this paper, we propose a new method, named ant colony optimization (ACO), to delineate the eyes automatically. In the proposed algorithm, each ant tries to find a closed path, and some pheromone is deposited on the visited path when the ant fmds a path. After all ants fmish a circle, the best ant will lay some pheromone to enforce the best path. The proposed algorithm is verified on several CT images, and the preliminary results demonstrate the feasibility of ACO for the delineation problem.  相似文献   

7.

In the Internet of Things (IoT), the number of devices connected to the internet, and they can collect and exchange information at any time. IoT is helpful for the progress of a smart city and different applications. Software-Defined Network (SDN) offers programmability and flexibility in the IoT network. Nevertheless, the adoption of the number of gadgets will increase the transmission delay and this will lead the network to heavy loaded. To overcome this issue, an efficient load balancing technique has to be presented in the SDN network. By considering this solution as an aim, spider monkey optimization algorithm based load balancing (LB-SMOA) is presented in this paper. Using this technique, the controller with minimum load is selected and this selected controller balances the load of the heavily loaded controller. Simulation results show that the performance of the proposed LB-SMOA outperforms the existing load balancing techniques in terms of average response time, packet loss rate, and throughput.

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8.
Many ant colony routing (ACR) algorithms have been presented in recent years, but few have studied the problem that ants will get stuck with probability in any terminal host when they are searching paths to route packets around a network. The problem has to be faced when designing and implementing the ACR algorithm. This article analyzes in detail the differences between the ACR and the ant colony optimization (ACO). Besides, particular restrictions on the ACR are pointed out and the three causes of ant being-stuck problem are obtained. Furthermore, this article proposes a new ant searching mechanism through dual path-checking and online routing loop removing by every intermediate node an ant visited and the destination host respectively, to solve the problem of ant being stuck and routing loop simultaneously. The result of numerical simulation is abstracted from one real network. Compared with existing two typical ACR algorithms, it shows that the proposed algorithm can settle the problem of ant being stuck and achieve more effective searching outcome for optimization path.  相似文献   

9.
The Internet of Things (IoT) means connecting everything with every other thing through the Internet. In IoT, millions of devices communicate to exchange data and information with each other. During communication, security and privacy issues arise which need to be addressed. To protect information about users’ location, an efficient technique should be devised. Several techniques have already been proposed for preserving location privacy in IoT. However, the existing research lags in preserving location privacy in IoT and has highlighted several issues such as being specific or being restricted to a certain location. In this paper, we propose a new location privacy technique called the enhanced semantic obfuscation technique (ESOT) to preserve the location information of a user. Experimental results show that ESOT achieves improved location privacy and service utility when compared with a well-known existing approach, the semantic obfuscation technique.  相似文献   

10.
蚁群算法中系统初始化及系统参数的研究   总被引:25,自引:4,他引:21       下载免费PDF全文
吴春明  陈治  姜明 《电子学报》2006,34(8):1530-1533
蚁群算法作为近年来一种新的模拟进化算法具有较强的发现解的能力,但同时也有收敛慢、耗费时间的缺点.本文针对各种不同规模的TSP问题,通过实验对各参数的设置做了研究,并对蚂蚁初始化提出了新的算法,并进行了实验验证.  相似文献   

11.
With the increasing number of sensors in the Internet of Things (IoT), network nodes are prone to load imbalance, which seriously affects the reliability and scalability of the IoT. In this paper, a method of load balancing is proposed to reduce the pressure of switches in IoT and improve the efficiency of switch. The method is based on software defined network (SDN) technology using dynamic traffic scheduling of server cluster (DTSSC) model. It obtains the traffic and load matrices for each server and achieves load balancing on each of them. This method has high efficiency and low overhead and is easy to deploy. The validity of this method is verified through experiments; ie, the load ratio of each server is balanced.  相似文献   

12.
改进蚁群算法在QoS路由中的应用与研究   总被引:1,自引:0,他引:1  
在分析传统蚁群算法缺陷及其在QoS路由中的应用的基础上,提出了一种与真实蚁群系统更加相符的基于双向寻路和信息素扩散的蚁群算法,采用来自源节点和目的节点两个方向的蚂蚁探路的同时进行信息扩散.仿真结果表明,该改进蚁群算法在网络规模较大的条件下仍能快速找到满足QoS路由性能指标的路由,节省了QoS路由搜索时间,提高了网络服务能力.  相似文献   

13.
The emergence of Internet of Things (IoT) is empowered by the availability of the high volume of smart sensors, Radio Frequency Identification, a suitable communication technologies and protocols. In the near future, the Internet will be full of heterogeneous connected devices. In recent years, the IoT has drawn significant attention as it can solve difficult problems. However, the heterogeneity of devices and the large scale networks expose the IoT to many challenges that must be addressed; otherwise, the systems performance will deteriorate. As an attempt to identify these challenges, this paper comprehensibly cites the main IoT concepts, the serious IoT challenges and the quality of services presented in the recent literature. It also investigates the corresponding main research directions and the proposed solutions. This paper can increase the knowledge of the reader since it is the first IoT survey that presents load balancing algorithms utilized in solving the extreme data storage challenge.  相似文献   

14.
Advances in hardware, software, communication, embedding computing technologies along with their decreasing costs and increasing performance have led to the emergence of the Internet of Things (IoT) paradigm. Today, several billions of Internet‐connected devices are part of the IoT ecosystem. IoT devices have become an integral part of the information and communication technology (ICT) infrastructure that supports many of our daily activities. The security of these IoT devices has been receiving a lot of attention in recent years. Another major recent trend is the amount of data that is being produced every day which has reignited interest in technologies such as machine learning and artificial intelligence. We investigate the potential of machine learning techniques in enhancing the security of IoT devices. We focus on the deployment of supervised, unsupervised learning techniques, and reinforcement learning for both host‐based and network‐based security solutions in the IoT environment. Finally, we discuss some of the challenges of machine learning techniques that need to be addressed in order to effectively implement and deploy them so that they can better protect IoT devices.  相似文献   

15.
Grid computing is increasingly considered as a promising next-generation computational platform that supports wide-area parallel and distributed computing. In grid environments, applications are always regarded as workflows. The problem of scheduling workflows in terms of certain quality of service (QoS) requirements is challenging and it significantly influences the performance of grids. By now, there have been some algorithms for grid workflow scheduling, but most of them can only tackle the problems with a single QoS parameter or with small-scale workflows. In this frame, this paper aims at proposing an ant colony optimization (ACO) algorithm to schedule large-scale workflows with various QoS parameters. This algorithm enables users to specify their QoS preferences as well as define the minimum QoS thresholds for a certain application. The objective of this algorithm is to find a solution that meets all QoS constraints and optimizes the user-preferred QoS parameter. Based on the characteristics of workflow scheduling, we design seven new heuristics for the ACO approach and propose an adaptive scheme that allows artificial ants to select heuristics based on pheromone values. Experiments are done in ten workflow applications with at most 120 tasks, and the results demonstrate the effectiveness of the proposed algorithm.  相似文献   

16.
一种基于改进蚁群算法的选播路由算法   总被引:4,自引:0,他引:4  
为了在网络负载较大的情况下实现多目标多路径的选播路由,该文根据蚂蚁寻径与选播路由的相似性,提出了一种基于改进蚁群算法的选播路由算法。在运用数据包传输的历史信息来模拟路径信息素的基础上,增加了目标地址泛洪负载信息来模拟食物气味散发的过程,使得各个节点可以获得服务器和链路的最新信息。节点根据路径上的信息素、食物的气味以及链路的可见度等综合生成概率表,作为后继蚂蚁路径选择的依据。运用NS-2对该算法进行仿真,测试结果表明它可以减少传输时延,降低服务器负载的波动幅度,实现链路的负载均衡,增加网络的容量,提高选播服务的可扩展性。  相似文献   

17.
Multiple-valued logic (MVL) synthesis is a problem that has attracted increased interest in recent years. The MVL synthesis problem is more involved compared to its binary counterpart. The search space for finding optimal MVL functional synthesis is enormous. Conventional deterministic methods for MVL functional synthesis are prohibitively expensive, indicating an eminent need for the use of iterative heuristic-based synthesis techniques. In this paper, an ant colony optimization (ACO) based heuristic algorithm for synthesis of MVL functions is proposed. The algorithm mimics the ants' behaviour in the real world. Real ants are found to be able to select the shortest path between their nest and food sources in the existence of alternate paths, or even hurdles between the two. The proposed ACO algorithm uses some of the known real ant techniques in finding the shortest paths to the (near) optimal number of product terms that can cover the minterms of a given MVL function. The proposed algorithm is tested using 50 000 randomly generated 2-variable 4-valued functions. The results obtained using the proposed approach show that the proposed approach outperforms existing direct cover (DC) techniques in terms of the average number of product terms (implicants) required to synthesize a given MVL function.  相似文献   

18.

In Internet of Things (IoT), the massive connectivity of devices and enormous data on the air have made information susceptible to different type of attacks. Cryptographic algorithms are used to provide confidentiality and maintain the integrity of the information. But small size, limited computational capability, limited memory, and power resources of the devices make it difficult to use the resource intensive traditional cryptographic algorithms for information security. In this scenario it becomes impertinent to develop lightweight security schemes for IoT. A thorough study on the lightweight cryptography as a solution to the security problem of resource-constrained devices in IoT has been presented in this work. This paper is a comprehensive attempt to provide an in-depth and state of the art survey of available lightweight cryptographic primitives till 2019. In this paper 21 lightweight block ciphers, 19 lightweight stream ciphers, 9 lightweight hash functions and 5 variants of elliptic curve cryptography (ECC) has been discussed i.e. in total 54 LWC primitives are compared in their respective classes. The comparison of the ciphers has been carried out in terms of chip area, energy and power, hardware and software efficiency, throughput, latency and figure of merit (FoM). Based on the findings it can be observed that AES and ECC are the most suitable for used lightweight cryptographic primitives. Several open research problems in the field of lightweight cryptography have also been identified.

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19.
为解决基于蚁群优化的图像边缘检测算法中信息素的作用不明显,难以获得全局最优解,从而降低目标边缘的检测精确度与效率等问题,提出一种基于细菌趋化性(BC)耦合蚁群优化(ACO)的边缘检测算法.通过细菌趋化性找到最佳解决方案,用于产生信息素的初值;将BC得到的信息素初值作为ACO的初始信息素,计算每只蚂蚁的行走概率,从而选择...  相似文献   

20.
Internet of Things (IoT) and its relevant technologies have been attracting the attention of researchers from academia, industry, and government in recent years. However, since the requirements of the IoT are quite different from what the Internet today can offer, several innovative techniques have been gradually developed and incorporated into IoT, which is referred to as the Future Internet of Things (FIoT). Among them, how to extract “data” and transfer them into “knowledge” from sensing layer to application layer has become a vital issue. This paper begins with an overview of IoT and FIoT, followed by discussions on how to apply data mining and computational intelligence to FIoT. An intelligent data management framework inspired by swarm optimization will then given. Finally, open issues and future trends of this field will be addressed.  相似文献   

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