Abstract Over the last decades Internet traffic has grown dramatically. Besides the number of transfers, data sizes have risen as well. Traditional transfer protocols do not adapt to this evolution. Largescale computational applications running on expensive parallel computers produce large amounts of data which often have to be transferred to weaker machines at the clients’ premises. As parallel computers are frequently... Over the last decades Internet traffic has grown dramatically. Besides the number of transfers, data sizes have risen as well. Traditional transfer protocols do not adapt to this evolution. Largescale computational applications running on expensive parallel computers produce large amounts of data which often have to be transferred to weaker machines at the clients’ premises. As parallel computers are frequently charged by the minute, it is indispensable to minimize the transfer time after computation succeeded to keep down costs. Consequently, the economic focus lies on minimizing the time to move away all data from the parallel computer whereas the actual time to arrival remains less (but still) important. This paper describes the design and implementation of a new transfer protocol, the Fast Send Protocol (FSP), which employs striping to intermediate nodes in order to minimize sending time and to utilize the sender’s resources to a high extent. Read More Read Less

Abstract The Session Initiation Protocol (SIP) is a signaling protocol that controls communication sessions such as conferencing, telephony, and instant messaging in the Internet community (RFC2543). Before a user gets to use an SIP service provided by a server, an authendication process must be finished. However, there are some security problems with SIP authentication yet to... The Session Initiation Protocol (SIP) is a signaling protocol that controls communication sessions such as conferencing, telephony, and instant messaging in the Internet community (RFC2543). Before a user gets to use an SIP service provided by a server, an authendication process must be finished. However, there are some security problems with SIP authentication yet to be solved, such as server spoofing, off-line password gussing attacks, and the use of the password table. In this article, we shall propose a new authentication scheme for SIP that does not need the password table. Read More Read Less

Abstract Nowadays, efficient graph query processing method is coming more and more important along with the structured data accumalating. Given a graphs from the database that are subgraphs of the query graph. In this paper, an algorithm is processed,which is founded on a CFG(closed frequent subgraph) based index, to answer graph contaiment query. CFG is... Nowadays, efficient graph query processing method is coming more and more important along with the structured data accumalating. Given a graphs from the database that are subgraphs of the query graph. In this paper, an algorithm is processed,which is founded on a CFG(closed frequent subgraph) based index, to answer graph contaiment query. CFG is a set of special frequent subgraph of a graph database. When query processes through this index, it gets back a smaller candidate answer set than other methods which means much less subgraph isomorphism calculation. Both theritical analysis and experimental evaluation result shows that the proposed method not only efficiently prunes the search branches in the feature index, but also efficiently reduces the subgrapg isomorphism test between the query graph and the indexed features. Read More Read Less

Abstract This paper presents some fundamental knowledge of image recognition of partially occluded objects, and brings forward an improved set of curve moment invariants to recognize occluded objects in images. Occluded objects in an image are not rich in information, while the improved curve moment invariants can represent those objects in a unique ay. Therefore, he occluded objects can be... This paper presents some fundamental knowledge of image recognition of partially occluded objects, and brings forward an improved set of curve moment invariants to recognize occluded objects in images. Occluded objects in an image are not rich in information, while the improved curve moment invariants can represent those objects in a unique ay. Therefore, he occluded objects can be fficiently recognized through their shape representation by the set of curve moment invariants as their features. A number of model objects are predefined in the experiments to build the prior knowledge database for the sake of matching and recognizing unknown objects in future input images. Imagepre-processing is employed for both model objects and unknown input objects to obtain their boundary and partition it into subparts. Corner points along the boundary are detected after image pre-processing so that the objects can be described by the curve moment invariants of each subpart. Finally, the matching of curve moment invariants between model object and unknown object is carried on to recognize the unknown object in the input scene image. The results of experiments show that this method is robust and efficient to recognize partially occluded objects in 2D images; furthermore, the invariance to the affine transformation of objects in mages in images are also proved in the paper. Read More Read Less

Abstract This paper addresses two fundamental research problems in the domain of context aware autonomic systems: the development of a generic context model that can be used to represent general purpose contexts in a system interpretable way and the autonomic context model management. The proposed context model uses wo equivalent and synchronized ways of representing the context:... This paper addresses two fundamental research problems in the domain of context aware autonomic systems: the development of a generic context model that can be used to represent general purpose contexts in a system interpretable way and the autonomic context model management. The proposed context model uses wo equivalent and synchronized ways of representing the context: a set based representation and an ontology based representation. The set based representation is used to evaluate the conditions under which the self-* processes should be executed in order to enforce the autonomic properties. The ontology representation is used by context aware applications for reasoning and learning purposes. The increasing complexity of execution environments of the context aware systems and the difficults of their management have headed us towards the necessity of defining and integrating the self-configuring autonomic paradigm in the context model management process.the self - configuring property is enforced by monitering the real world context in order to detect context variations or conditions for which the context artifacts must be updated. Read More Read Less

Abstract In this paper, we present a new device brought online thanks to our Collaborative Remote Laboratories framework. Whereas previous devices integrated in our remote laboratory belongs to the domain of electronics, such as Vector Network Analyzers, the device at the concern in this paper is an antenna workbench. Because the middleware and framework for our environment were designed to be... In this paper, we present a new device brought online thanks to our Collaborative Remote Laboratories framework. Whereas previous devices integrated in our remote laboratory belongs to the domain of electronics, such as Vector Network Analyzers, the device at the concern in this paper is an antenna workbench. Because the middleware and framework for our environment were designed to be reusable, we wanted to illustrate these qualities by providing a completely new device in our Online Engineering catalog. After presenting the device to be put online, we will expose the software development efforts required in regards to the reusability of the solution. Read More Read Less

Abstract The paper shows the results of the evaluation of three remote labs implemented at the University of Deusto -WebLab-Deusto- as a learning tool. The paper presents the results of the surveys done by students since 2004. This survey consists of some questions and its main objective is to measure the acceptance, usability and usefulness of the remote laboratory developed at... The paper shows the results of the evaluation of three remote labs implemented at the University of Deusto -WebLab-Deusto- as a learning tool. The paper presents the results of the surveys done by students since 2004. This survey consists of some questions and its main objective is to measure the acceptance, usability and usefulness of the remote laboratory developed at University of Deusto. To the best of our knowledge, this survey is the largest one in terms of number of academic years and total number of students involved. Read More Read Less

Abstract The aim of this work is to develop a simultaneous multi user access system – READ (Remote ASIC Design and Test) that allows users to perform test and measurements remotely via clients running on mobile devices as well as on PCs. The system also facilitates the remote design of circuits with the PACDesigner The system is controlled by LabVIEW and... The aim of this work is to develop a simultaneous multi user access system – READ (Remote ASIC Design and Test) that allows users to perform test and measurements remotely via clients running on mobile devices as well as on PCs. The system also facilitates the remote design of circuits with the PACDesigner The system is controlled by LabVIEW and was implemented using a Data Acquisition Card from National instruments. Such systems are specially suited for manufacturing process monitoring and control. The performance of the simultaneous access was tested under load with a variable number of users. The server implements a queue that processes user’s commands upon request. Read More Read Less

Abstract In this paper, new strategies for prefetching and cache replacement are proposed. The proposed pre-fetching algorithm considers the geographical and semantic adjacency between queried items. The strategy is to pre-fetch the most probable secondary service as a by-product of the execution of a query to a primary service. Association rule mining is used for determining the secondary item that should... In this paper, new strategies for prefetching and cache replacement are proposed. The proposed pre-fetching algorithm considers the geographical and semantic adjacency between queried items. The strategy is to pre-fetch the most probable secondary service as a by-product of the execution of a query to a primary service. Association rule mining is used for determining the secondary item that should be pre-fetched. The latter part of the paper deals with a cache replacement algorithm PAID+ (Probability Area Inverse Distance +) which takes into account the access probability and distance between the mobile client and the service item which suits a pre-fetching environment. The experimental evaluations using synthetic datasets show the cache pre-fetch and replacement policy PAID+ are effective in improving the system performance in terms of the cache hit ratio of mobile clients. Read More Read Less