Priority dropping mechanism (PDM) to random early detection (RED) algorithm to protect the video layers selectivity from performance and throughput deterioration was applied. A receiver oriented multicast congestion c...
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Priority dropping mechanism (PDM) to random early detection (RED) algorithm to protect the video layers selectivity from performance and throughput deterioration was applied. A receiver oriented multicast congestion control algorithm SPLIT was introduced. A packet classification scheme (PCS) implemented in SPLIT makes all lost packets concentrated in video layers of lower priority. It was shown that with varying queue length packet loss in the Base high layer less when compared to the remaining enhancement high layers.
The nearly three dozen core technologies of computing sit in a simple framework defined by great principles and by computing practices. The great principles are of two kinds, mechanics and design. computing mechanics ...
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ISBN:
(纸本)1581137982
The nearly three dozen core technologies of computing sit in a simple framework defined by great principles and by computing practices. The great principles are of two kinds, mechanics and design. computing mechanics comprises computation, communication, coordination, recollection, and automation. Design principles address concerns for complexity, resilience, performance, evolvability, and security. Practices comprise programming, systems, modeling, innovating, and applying. This framework opens many new possibilities for teaching computer science, including new approaches to programming. The new CS curriculum at the Naval Postgraduate School is based on the framework presented here.
We study the homology of a filtered d-dimensional simplicial complex K as a single algebraic entity and establish a correspondence that provides a simple description over fields. Our analysis enables us to derive a na...
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We study the homology of a filtered d-dimensional simplicial complex K as a single algebraic entity and establish a correspondence that provides a simple description over fields. Our analysis enables us to derive a natural algorithm for computing persistent homology over an arbitrary field in any dimension. Our study also implies the lack of a simple classification over non-fields. Instead, we give an algorithm for computing individual persistent homology groups over an arbitrary PIDs in any dimension.
Collaborative Virtual Environments (CVE) are a form of telecommunication technology that bring together co-located or remote, participants within a spatial social and information context. Collaboration occurs between ...
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ISBN:
(纸本)0769522327
Collaborative Virtual Environments (CVE) are a form of telecommunication technology that bring together co-located or remote, participants within a spatial social and information context. Collaboration occurs between people and often around shared objects. Fruitful cooperation is helped by natural and intuitive ways of communicating and sharing, for which responsiveness and consistency are leading factors. Many CVEs maximise local responsiveness through a process of localisation and database replication, increasing responsiveness at the cost of lowering consistency. This is acceptable provided the application does not require the shared manipulation of objects. Those that do, require consistency control that provide sufficient synchronisation, ordering and update control, whilst maximising concurrence and thus the responsiveness of the system. This paper describes the major issues and principles of consistency control and demonstrates how we have applied many of these principles in three CVEs.
A number of recent research studies have explored ways to improve TCP throughput in IEEE 802.11 mobile ad hoc networks. In particular, hidden terminal effects caused by interference have been shown to degrade TCP perf...
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ISBN:
(纸本)1581139535
A number of recent research studies have explored ways to improve TCP throughput in IEEE 802.11 mobile ad hoc networks. In particular, hidden terminal effects caused by interference have been shown to degrade TCP performance and have been dealt with, in previous work, by restricting the maximum congestion window size. We have pursued an alternative approach and have developed a TCP variant which adjusts the sending rate increase to achieve competitive goodput for TCP connections. In this paper, we demonstrate that a slower sending rate increase during the congestion avoidance phase of TCP leads to improved performance for TCP Reno while eliminating the negative effects inherent in restricting the maximum congestion window size. A performance comparison against existing solutions under various mobility conditions is also included. Copyright 2004acm.
Genetic Algorithms (GAs) have long been applied to tackling scheduling problems, particularly JSP, with varying degrees of success. However despite advances in GA theory, GAs remain a computationally expensive method ...
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ISBN:
(纸本)0780385152
Genetic Algorithms (GAs) have long been applied to tackling scheduling problems, particularly JSP, with varying degrees of success. However despite advances in GA theory, GAs remain a computationally expensive method of approaching scheduling problems [1]. In particular for practical scheduling problems, such as those outlined in [2] & [3], GAs require extensive resources. We propose a grid based high-throughput computing framework that utilises spare computing capacity, which is distributed across a network, to address real scheduling problems. We use web-services as a gateway to this high-throughput computing environment.
Automotive applications are mostly designed to low costs. Efforts to reduce noise, increase efficiency and expand duty cycles call for optimised machine designs. Sophisticated machine designs require long FEA computin...
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Automotive applications are mostly designed to low costs. Efforts to reduce noise, increase efficiency and expand duty cycles call for optimised machine designs. Sophisticated machine designs require long FEA computing times for the optimisation process. Combinations of calculation approaches decrease the total computing time and therefore costs significantly. A combined analytical and numerical calculation approach is presented, using analytical means for pre-design to match power requirements (torque, speed, current) and FE calculation for magnetic verification. The method is applied to a six-phase claw-pole alternator design.
Literature on women in computing points out that computer science is not being effective at attracting and retaining women. Introduction to Media Computation is a new CS1 aimed especially at non-majors which was desig...
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ISBN:
(纸本)1581137982
Literature on women in computing points out that computer science is not being effective at attracting and retaining women. Introduction to Media Computation is a new CS1 aimed especially at non-majors which was designed explicitly to address the concerns of women in computer science, such as the lack of relevance and creativity. The course is contextualized around the theme of manipulating and creating media. Of the 121 students who took the course (2/3 female), only three students dropped (all male), and 89% completed the course with a grade C or better. This paper presents data from interviews with women in the Media Computation class, then contrasts with interviews in a more traditional CS1. Copyright 2004acm.
Quantum spin models describe quantum magnetism in Solid-State systems. Even when some of these models were proposed at the very beginning of quantum mechanics, their study is hindered by the fact that they are very di...
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ISBN:
(纸本)0819458279
Quantum spin models describe quantum magnetism in Solid-State systems. Even when some of these models were proposed at the very beginning of quantum mechanics, their study is hindered by the fact that they are very difficult to be studied numerically. Quantum computers could allow us to solve this problem, because they can be used for the efficient simulation of many-body quantum systems. In our work we propose an alternative that is easier than quantum computation. By means of lasers, a set of trapped ions can simulate the physics of interacting spins in such a way, that the range and the sign of the interactions can be tuned by the choice of lasers and trapping conditions. Our proposal can be applied to the simulation of Ising, XY and Heisenberg models.
The paradigm of grid computing has been successfully applied in the domain of computationally-intensive applications supporting scientific research using server-class computers interconnected by wired network The user...
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ISBN:
(纸本)0769521088
The paradigm of grid computing has been successfully applied in the domain of computationally-intensive applications supporting scientific research using server-class computers interconnected by wired network The users of the existing and growing number of wireless mobile devices often demand more computational power than their devices can currently provide. We propose using the computational grid paradigm to build a problem-solving environment for wireless mobile devices.
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