16320573
A Routing Protocol for Hierarchical LEO/MEO Satellite IP Networks
The rapid growth of Internet-based applications pushes broadband satellite networks to carry on IP traffic. In previously proposed connectionless routing schemes in satellite networks, the metrics used to calculate the paths do not reflect the total delay a packet may experience. In this paper, a new Satellite Grouping and Routing Protocol (SGRP) is developed. In each snapshot period, SGRP divides Low Earth Orbit (LEO) satellites into groups according to the footprint area of the Medium Earth Orbit (MEO) satellites. Based on the delay reports sent by LEO satellites, MEO satellite managers compute the minimum-delay paths for their LEO members. Since the signaling traffic is physically separated from the data traffic, link congestion does not affect the responsiveness of delay reporting and routing table calculation. The snapshot and group formation methods as well as fast reacting mechanisms to address link congestion and satellite failures are described in detail. The performance of SGRP is evaluated through simulations and analysis.
15960465
InterPlaNetary Internet: state-of-the-art and research challenges
The developments in the space technologies are enabling the realization of deep space scientific missions such as Mars exploration. InterPlaNetary (IPN) Internet is expected to be the next step in the design and development of deep space networks as the Internet of the deep space planetary networks. However, there exist significant challenges to be addressed for the realization of this objective. Many researchers and several international organizations are currently engaged in defining and addressing these challenges and developing the required technologies for the realization of the InterPlaNetary Internet. In this paper, the current status of the research efforts to realize the InterPlaNetary Internet objective is captured. The communication architecture is presented, and the challenges posed by the several aspects of the InterPlaNetary Internet are introduced. The existing algorithms and protocols developed for each layer and the other related work are explored, and their shortcomings are pointed out along with the open research issues for the realization of the InterPlaNetary Internet. The objective of this survey is to motivate the researchers around the world to tackle these challenging problems and help to realize the InterPlaNetary Internet.
206109439
How did university departments interweave the Web: A study of connectivity and underlying factors
This paper presents two studies of the use of the WWW in Scottish universities and American land-grant universities. First, we investigated the relationship between the organisational profile of a university department in Scotland and its structural connectivity on the WWW. A Spearman rank order correlation analysis revealed a number of strong correlation relationships between structural connectivity measures and the organisational profile based on research assessment exercise ratings, teaching quality assessments, student‐staff ratios and funding levels. Linkage patterns from 13 Scottish academic sites to commercial sites in Britain and America highlighted the impact of culture and the appropriateness of information technologies on the acceptance of the WWW. The second study is a content survey of WWW-based education activities in American land-grant universities to investigate successful applications of these enabling techniques in education. The two studies together highlighted cultural, political and technological interactions in the use of the WWW. q 1998 Elsevier Science B.V. All rights reserved
205000421
A Simple Approach to Implementing Multiplication with Small Tables
Abstract A new approach for implementing multiplication with a small table is presented. This approach is much simpler and thus easier to be implemented.
43110
A study of self-adjusting quality of service control schemes
We report simulation methods and results for analyzing a self-adjusting quality of service (QoS) control scheme for multimedia/telecommunication systems based on resource reservation. We study the case in which high priority clients' QoS requirement is not changed throughout the service period, while low priority clients' QoS may be adjusted by the system between the maximum and minimum QoS levels specified in order to adapt to the load of the system. The goal of the system design is to optimize the system reward as a result of servicing clients with different QoS and reward/penalty requirements. A QoS manager in these systems can do a table lookup operation using the simulation result reported to optimize the system total reward dynamically in response to changing workloads during the run time. The simulation result is particularly applicable to multimedia and telecommunication systems in which dynamic QoS negotiation/renegotiation is used as a mechanism to optimize the overall system performance.
12972622
DIKNN: An Itinerary-based KNN Query Processing Algorithm for Mobile Sensor Networks
Current approaches to k nearest neighbor (KNN) search in mobile sensor networks require certain kind of indexing support. This index could be either a centralized spatial index or an in-network data structure that is distributed over the sensor nodes. Creation and maintenance of these index structures, to reflect the network dynamics due to sensor node mobility, may result in long query response time and low battery efficiency, thus limiting their practical use. In this paper, we propose a maintenance-free, itinerary-based approach called density-aware itinerary KNN query processing (DIKNN). The DIKNN divides the search area into multiple cone-shape areas centered at the query point. It then performs a query dissemination and response collection itinerary in each of the cone-shape areas in parallel. The design of the DIKNN scheme also takes into account challenging issues such as the the dynamic adjustment of the search radius (in terms of number of hops) according to spatial irregularity or mobility of sensor nodes. The simulation results show that DIKNN yields substantially better performance and scalability over previous work, both as k increases and as the sensor node mobility increases. It outperforms the second runner with up to 50% saving in energy consumption and up to 40% reduction in query response time, while rendering the same level of query result accuracy.
2888098
Evolutionary interactive music composition
This paper proposes the CFE framework---Composition, Feedback, and Evolution---and presents an interactive music composition system. The system composes short, manageable pieces of music by interacting with users. The most important features of the system include creating customized music according to the user preference and providing the facilities specifically designed for producing large amounts of music. We present the structure as well as the implementation of the system and the auxiliary functionalities that enhance the system. We also introduce the auto-feedback test with which we verify and evaluate the interactive music composition system.