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.
Programming with atomic sections is a promising alternative to locks since it raises the abstraction and removes deadlocks at the programmer level. However, implementations of atomic sections using software transactional memory (STM) support have significant bookkeeping overheads. Additionally, because of the speculative nature of transactions, aborts can be frequent greatly lowering application performance...
We propose two scheduling protocols which are applicable to two-hop relay networks based on mobile WiMAX system: the first protocol adopts a persistent scheduling (PS) scheme in both hops, called the PS-PS protocol, while the second protocol adopts the PS scheme only in the first hop and the dynamic scheduling (DS) scheme in the second hop, called the PS-DS protocol. We optimize the above two protocols...
Streaming services have been gaining much popularity in the Internet. The widespread adoption of broadband residential access enables individual users to use new bandwidth demanding services. Peer-to-Peer (P2P) multicasting approach using an overlay network to provide communication between peers is a valuable proposal for streaming since it provides rapid deployment at relatively low cost. Most of...
Bacterial foraging optimization (BFO) algorithm is one of the newest nature inspired optimization algorithm, based on social foraging behavior of Escherichia coli. However, this swarm-based algorithm is computationally expensive due to the slow nature of the collective intelligence of bacterial swarm. This paper presents a novel way to accelerate BFO. The novel bacterial foraging oriented by differential...
Enhanced Biogeography-Based Optimization (EBBO) technique is an improved version of BBO. BBO mainly uses the idea of probabilistically sharing features (Migration operator) among solutions based on the fitness values. The exploitation ability of BBO is good in comparison to many optimization techniques due to efficient sharing of information among solutions. However, migration operator creates similar...
A two-stage filtering approach based on implicit semantics of web service description and WordNet is proposed to identify candidate services during semantic service discovery using semantic reasoners. In the first stage, the candidate services relevant to the given service query are identified after filtering out irrelevant services. In the second stage, the trust score of each candidate service is...
A cooperative ratio-based scheduling scheme with minimal signaling to enhance network throughput and fairness in wireless ad hoc network is presented in this paper. Throughput and fairness maximization problem in a finite horizon (short term) is formulated as a novel multi-window optimization problem. Through analysis users' thresholds are shown to be time variant to achieve throughput maximization...
This paper studies the joint design of transmit beamformers, receive combiners, and linear relaying matrix for a two-way amplify-and-forward (AF) relay system equipped with multiple-antennas at sources and relay. A single data stream is transmitted by each source. Due to the non-convexity of the optimization problem, finding a solution that maximizes the sum-rate appears to be intractable. Hence,...
A deployment strategy of hierarchical structure wireless sensor network. (HSWSN) is studied, HSWSN are composed basic station (BS), relay devices (RNs) and sensors (SNs). In this paper, the mode of system and energy consumption are proposed, the deployment strategy especial relay devices is proposed, and some important such that energy consumption density (ECD), distribution probability of RN consumption...
The generalized assignment problem is a well-known NP-complete problem whose objective is to find a minimum cost assignment of a set of jobs to a set of agents by considering the resource constraints. Dynamic instances of the generalized assignment problem can be created by changing the resource consumptions, capacity constraints and costs of jobs. Memory-based approaches are among a set of evolutionary...
Multicast support is critical and a desirable feature of multi-radio wireless mesh networks. However, the nature of wireless network, i.e. broadcasting and interference, makes it a challenge to efficiently support multicast services. In this paper, we study how to build a multicast structure with maximum average throughput in terms of minimum transmission time and channel interference in a multi-radio...
We present a service resource selection and scheduling approach capable of maximizing the resource utilization rate (RUT) and the requirement satisfaction degree (RSD) by bundling multiple customer requirements (CRs). In traditional approaches, each CR is optimally satisfied by independently selecting a set of candidate service resources. This possibly leads to a low RUT and low RSD. In our approach,...
The Ant Colony Optimization algorithms (ACO) are computational models inspired by the collective foraging behavior of ants. By looking at the strengths of ACO, they are the most appropriate for scheduling of tasks in soft real-time systems. In this paper, ACO based scheduling algorithm for real-time operating systems (RTOS) has been proposed. During simulation, results are obtained with periodic tasks,...
We consider the problem of cognitive code-division channelization (simultaneous power and code-channel allocation) for secondary transmission links co-existing with an unknown primary code-division multiple-access (CDMA) system. We first develop a blind primary-user identification scheme to detect the binary code sequences (signatures) utilized by primary users. To create a secondary link we propose...
Microgrids can be defined as entities which include low voltage networks, loads, energy storage systems, and several small modular generation systems. Various uncertainties exist in microgrids. They are caused by load and the intermittent output power of some distribution generation units. In a spinning reserve estimation problem, all uncertainties are rounded. In this paper, how the various uncertainties...
In this paper we study the problem of relay-enhanced cell (REC) coverage for which relay location is optimized to maximize the achievable REC radius. The problem is investigated for both Rayleigh and Rician relay fading channels, under a pre-determined user's outage probability constraint. We propose a statistical approach to formulate the problem and develop an optimization algorithm for it. The...
Efficiency of parallel branch and bound algorithms depends on the selection strategy. The influence to the performance of parallel MPI branch and bound algorithm with simplicial partitions and aggregate Lipschitz bound using different selection strategy is evaluated experimentally. The experiments have been performed solving a number of multidimensional test problems for global optimization.
Based on dynamic berth allocation problem (BAP) in container terminal (CT), a schedule reliability problem (SRP) optimization model is proposed. The model focuses on the minimum average schedule missed hours of ships between the ship schedule departure time and the actual departure time to enhance the schedule reliability (SR) of ships in CT, and the quay crane allocation is considered in this model...
This paper proposes an alternative approach to efficient solving of nonlinear constrained optimization problems using evolutionary algorithms. It is assumed that the separate-ness of the feasible regions, which imposes big difficulties for evolutionary search, is partially resulted from the complexity of the nonlinear constraint functions. Based on this hypothesis, an approximate model is built for...
IP multicast has proved to be the best approach for large scale multimedia communications enhancing video transmissions for applications like IPTV, video conferencing or other best-effort real-time audio/video applications. IP multicast connectivity, unfortunately, relays on certain network technologies and protocols and is present only in some areas of the Internet, while the majority of hosts lack...
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.