Search results for "Computer network"
showing 10 items of 1634 documents
Understanding 802.11e contention-based prioritization mechanisms and their coexistence with legacy 802.11 stations
2005
The IEEE 802.11e task group has reached a stable consensus on two basic contention-based priority mechanisms to promote for standardization: usage of different arbitration interframe spaces and usage of different minimum/maximum contention windows. The goal of this article is to provide a thorough understanding of the principles behind their operation. To this purpose, rather than limit our investigation to high-level (e.g. throughput and delay) performance figures, we take a closer look at their detailed operation, also in terms of low-level performance metrics (e.g., the probability of accessing specific channel slots). Our investigation on one hand confirms that AIFS differentiation prov…
The impact on port competition of the integration of port and inland transport services
2015
The performance of the transport chain is important for the efficiency and competitiveness of an economy. In the context of port competition, there has been an increasing cooperation between firms involved in the intermodal transport chain including seaport services. This paper examines the economic incentives and welfare implications to the integration of port activities with inland transport services under inter-ports competition. Although ports find it advantageous to engage in such integration process it may be detrimental to welfare, since shippers’ aggregate surplus decreases – noting that farther away users benefit at the expense of those closer to the ports. Several scenarios not le…
Benchmarking the port services: a customer oriented proposal
2004
In recent years, ports have experienced a period of significant growth and development along with intense inter‐port rivalry as a consequence of intermodality and hinterland development. It is therefore vital that port management bodies define and implement suitable strategies. This paper aims to adapt the benchmarking technique to the sphere of ports. Compares the activity of a port with that of its competitors, which is considered to be excellent. This is a strategic approach where consideration of the needs of the client, shipping lines and export‐import companies is the axis of the benchmarking process.
Using QSPS in Developing and Realization of a Production Line in Automotive Industry
2010
<p>Using the QSPS (Quality System for the production software) for industrial projects and not only therefore, has led to accurate running of the production line from beginning of the SOP (Start of Production). This paper presents the application way of the QSPS at one of the strongest European automotive company. By using of this system several significant costs savings and quality improvement can be observed.<br /> The content of this paper will show step by step how to use QSPS for the integration of a production line in the traceability system from a big company in automotive industry.<br /> The production line involved contains 56 production equipments, which have to …
A Conclusive Analysis of the Finite-Time Behavior of the Discretized Pursuit Learning Automaton
2019
Author's accepted version (post-print). © 20XX IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Available from 20/03/2021. This paper deals with the finite-time analysis (FTA) of learning automata (LA), which is a topic for which very little work has been reported in the literature. This is as opposed to the asymptotic steady-state analysis for which there are, probabl…
Neural network approach to solving fuzzy nonlinear equations using Z-numbers
2020
In this article, the fuzzy property is described by means of the Z-number as the coefficients and variables of the fuzzy equations. This alteration for the fuzzy equation is appropriate for system modeling with Z-number parameters. In this article, the fuzzy equation with Z-number coefficients and variables is tended to be used as the models for the uncertain systems. The modeling issue related to the uncertain system is to obtain the Z-number coefficients and variables of the fuzzy equation. Nevertheless, it is extremely hard to get the Z-number coefficients of the fuzzy equations. In this article, in order to model the uncertain nonlinear systems, a novel structure of the multilayer neura…
Extracting similar sub-graphs across PPI Networks
2009
Singling out conserved modules (corresponding to connected sub-graphs) throughout protein-protein interaction networks of different organisms is a main issue in bioinformatics because of its potential applications in biology. This paper presents a method to discover highly matching sub-graphs in such networks. Sub-graph extraction is carried out by taking into account, on the one side, both protein sequence and network structure similarities and, on the other side, both quantitative and reliability information possibly available about interactions. The method is conceived as a generalization of a known technique, able to discover functional orthologs in interaction networks. Some preliminar…
An Internet-Based Self-Help Program for the Treatment of Fear of Public Speaking: A Case Study
2008
ABSTRACT This article discusses the development of the first totally self-administered online CBT program for the treatment of a specific social phobia (fear of public speaking) called talk to me. The online program includes three parts. The assessment protocol gives the patient information about the problem, including impairment, severity, and the degree of fear and avoidance regarding the main feared situations. The structured treatment protocol ensures that the patient does not skip any steps in the treatment. The treatment protocol is a CBT program that provides exposure to the feared situation using videos of real audiences. Finally, the control protocol assesses treatment efficacy, no…
An efficient distributed approach for dynamic multicast trees
2005
In this paper we present a distributed algorithm for constructing efficient multicast trees in large networks. The algorithm allows the set up of effective distribution trees using a coordination protocol among the network nodes. The algorithm has been implemented and extensively tested both in simulation, and on experimental networks. Performance evaluation indicates that our approach outperforms the state-of-the-art distributed algorithms for multicast tree setup, providing good levels of convergence time and communication complexity. Furthermore, we introduce a distributed technique for dynamically updating the multicast tree. The approach monitors the accumulated damage as nodes join or…
Research Direction for Developing an Infrastructure for Mobile & Wireless Systems: Consensus Report of the NSF Workshop Held on October 15, 2001 …
2002
The recent NSF Workshop on Infrastructure for Mobile and Wireless Systems, held on Oct. 15, 2001 in Phoenix had a goal of defining and establishing a common infrastructure for the discipline of mobile wireless networking. This consensus-based paper is the outcome of that workshop. The paper provides a foundation for implementation, standardization, and further research and discussion on the issues of what should constitute such an infrastructure. Workshop participants came from many different wireless communities, including those of communications, operating systems, core networking, mobility, databases, and middleware. The workshop presented various research directions in the field and inc…