The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In flexible manufacturing systems (FMS), each job is formed of a set of operations that should be executed consecutive. Determining the sequence of operations and assigning proper machine to each operation are two important problems in scheduling FMS's. This is an NP-hard problem. Recently using heuristic methods, numerous algorithms are presented for solving this problem. In this paper for scheduling...
Service discovery is an important part of nodes communication and collaboration infrastructure in grid computing and the first stage of grid computing scheduling stages. Thus service discovery is very effective in performance and efficiency of grid. Ad hoc grid is one of the earlier distributed systems that combine capabilities of grid computing and flexibility of ad hoc network. Therefore service...
In this paper a new algorithm based on the centralized algorithm for mutual exclusion in distributed systems is proposed that instead of one coordinator uses two coordinator On separate sites (But every moment One of them as coordinator whole system).In our method, if for any reason main Coordinator crashes, until recovery it, secondary coordinator controls critical section versus Simultaneous accesses...
Power-aware routing, have been studied to avoid energy-scarce sensors and achieve network lifetime improvement but recently, it was noticed that sink mobility can also be used to improve network lifetime by avoiding excessive transmission overhead at nodes that are close to the location that would be occupied by a static sink. Also in many situations, a static sink may be unfeasible because of deployment...
One of the weaknesses and drawbacks of a computer compared to a human being is the creativity and intelligence of a human being in encountering with different problems and his power of deduction and reasoning. Therefore computer engineers have been trying to make computers more intelligent and inferential and reasonable in encountering with different problems. Thus in this article we have tried to...
This paper presents a new adaptive and dynamic routing algorithm called AAODV for mobile ad hoc networks inspired by Ant Colony Optimization algorithms. This algorithm is proposed by maintaining the nature of the Ad hoc On-demand Distance Vector (AODV) routing through the use of Ant Colony Optimization. AAODV maintains the on-demand nature of AODV but works in an adaptive manner. It does not send...
According to the growth of information sources in recent years along the Web, many of Web servers have been dedicated to the information sources storage. Until yet many methods are presented for storing and transforming information on the Web in the case of paralleling or processing. But one of the researcher's challenges in derivation and restoring data in data mining and information retrievals are...
Several position-based routing protocols have been developed for mobile ad hoc networks. Many of these protocols assume that a location service is available which provides location information on the nodes in the network. In this article, we apply fuzzy logic system to a better management of location update operation in hierarchical location services. Our methods are different in last step of location...
Quality-of-Service Multicast routing is a well-known NP-complete problem as constrained Steiner tree problem, which has various real-time multimedia applications in highspeed networks. The bandwidth-delay-constrained least-cost multicast routing algorithms based on Tabu Search are proposed in this paper. These algorithms can improve the search speed, and make a better solution by using one of the...
Multicast routing with quality-of-service constraints is one of the most important problems in computer networks as constrained Steiner tree problem. It is a well-known NP-complete problem, which has various real-time multimedia applications in high-speed networks. In this paper, we propose algorithms to solve the bandwidth-delay-constrained least-cost multicast routing problem based on Tabu search...
In the real world, teams use a set of primitive strategies to achieve goal that in fact consists of consecutions of the passes and the movementspsila manner of the players for achieving goal. By using case based reasoning, it is possible, along with using primitive strategies, to register a successful succession to achieve goal, or a shot on goal, in the case base; and in the similar cases these strategies...
As the packet/cell loss ratio (PLR/CLR) is counted as one of the major quality of service (QoS) requirements; in this paper we proposed a linear upper bound expression for the loss probability approximation in high-speed communication network technologies. These technologies can support multiple classes of traffic with different QoS requirements and diverse traffic characteristics, by the use of traffic...
The important problem of distributed database systems(DDBs) is "data allocation". There are many methods for this problem and there are two measures for compare these models: Minimal cost and performance. In this paper we use a new method for using genetic algorithm. At first we generate clusters based on the communication cost between the sites,then perform genetic algorithm on these clusters...
By omitting sensors which have incorrect action in a wireless sensor network, network is reorganized again and it causes the consumption of energy and may also cause that some parts of the network go out of the coverage. The functionality of the network will be lowered when a node is thrown out from the network, so designing a sensor network with low consumption of energy is one of the prominent trends...
Rumor routing is a classic routing algorithm based on agents’ random walk. This paper proposes a novel approach based on this routing algorithm. Here, we try to improve the latency and energy consumption of the traditional algorithm using propagation of query and event agents within straight lines, instead of using purely random walk paths. As can be seen in our results, this method improves the delivery...
Multicast routing with quality-of-service constraints is one of the most important problems in computer networks as constrained Steiner tree problem. It is a well-known NP-complete problem, which has various real-time multimedia applications in high-speed networks. In this paper, we propose algorithms to solve the bandwidth-delay-constrained least-cost multicast routing problem based on Tabu Search...
The severe energy constraints of wireless sensor networks (WSNs) require energy-efficient communication protocols in order to fulfill the objectives of the application. Cross-layer design is a technique which can potentially be used to improve the overall performance of WSNs by way of jointly optimizing and exploiting the interactions between various layers of the network protocol stack This paper...
In this paper, we present two new ldquospatiotemporal multicastrdquo protocols for supporting applications which require spatiotemporal coordination in sensor networks. The spatiotemporal character of mobicast relates to the obligation to deliver a message to all the nodes that will be present at time t in some geographic zone Z, where both the location and shape of the delivery zone are a function...
Uncoordinated checkpointing protocol is a simple protocol used in many distributed systems for fault tolerance. In this paper, we discuss on the size of rollback it has in the presence of failures. In order to determining the recovery line in checkpoint-based recovery, we first study to common approaches: dependency graph and checkpoint graph and provide some algorithms for these approaches. Then...
This paper presents a validation model for the DSR routing protocol that includes a specification of the protocol and a test scenario. The scenario tests the conformance of a system implementation. The specification has been performed using the SDL language that developed by ITU-T and the scenario has been generated from the specification in a tool like Cinderella SDL. The test generation method is...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.