Iman Almomani Software Technology Research Laboratory (STRL), De Montfort University

Wireless Mobile Ad hoc NETwork (WMANET) is a group of independent wireless (Mobile/ Semi Mobile) nodes communicating on a peer-to-peer basis with no pre- established infrastructure. The unique characteristics of WMANET make such networks highly vulnerable to security attacks when compared with wired networks or infrastructure-based wire less networks. This paper proposes a novel security algorithm for managing digital certificates when all WMANET nodes are Full y Managed (FM) by other heterogeneous infrastructure-based wireless networks such as WLANs and cellular systems. The new security algorithm, which is called FM-WMANET, examines the integration of heterogeneous wireless networks to enhance the performance of WMANETs from the security perspectives. FM-WMANET presents a novel integrated key mana gement system that is based on the hierarchal trust models used by the Public Key Infrastructures (PKIs) of extant heterogeneous wireless networks. FM-WMANET is still fully distributed and provides a high level of securi ty, availability, flexibility and efficiency key management services for WMANETs. Graph theory a nd network simulator NS-2 are used to represent the security system proposed by FM-WMANET, study its performance and demonstrate its effectiveness.

Kaustubh Patil LIACC-NIAAD, University of Porto, R. Ceuta, 118–6o Researcher, Porto Researcher, 4050- Researcher, Portugal Researcher

We present a graph theoretic technique for automatic text summarization aimed at producing extractive summaries of a single document. In our system, called as SumGraph, text is represented as a graph with sentences as nodes while weights on the links represent intra-sentence dissim ilarity. Novelty of our approach lies in the use of Pathfinder Network Scaling (PFnet) technique representing conceptual organization of the text which in turn is used to compute importance of a sentence in the text. Importance of a sentence is defined using its centrality in the PFnet. Use of Latent Semantic Analysis (LSA) is also investigated. PFnet and LSA have been shown to model human aspects of semantic memory and linguistic acquisition respectively. The system is empirically evaluated on DUC2001 and DUC2002 datasets using ROUGE measure. Re sults show that SumGraph perform s better than other systems, including a commercial summarizer. Use of LSA did not show any improvement in ROUGE score. We also show that SumGraph is statis tically different than other methods using a non-parametric statistical test.

Jun Miyazaki Graduate School of Information Science, Nara Institute of Science, Technology Researcher

In this paper, we describe heuristic rules for choos ing an appropriate access path for a given query in main memory databases using a functional memory system. We have asserted that conventional cache- based memory access is not suitable for query processing in main memory databases. To cope with this problem, we have proposed three hardware-supporte d memory access scheme s. If we select an appropriate memory acce ss scheme from the three proposed sche mes and the cache-based access, the execution time of query processing can be reduced. In this paper, we derive heuristic rules on which access path should be selected and show its impact on execution time through experimentation.

Hilko Donker Dresden University of Technology, Department of Computer Science, Helmholtzstr. Researcher

Hyper videos introduce the possibilities of navigating and controlling the flow of information in a non- linear information structure to videos as we know th em from hyper texts. In this paper we are going to analyze the design of links in hyper videos by show ing the possibility of representing links in and the design options in a linkage scenario. In a linkage scenario links can be presented by means of effects or as explorative links. Links by means of effects can be represented by frames, by contrast in color, by three-dimensional objects or by illumination effects. E xplorative links have to be discovered by the user in a scene. Explorative links can be represented by words on objects, by signs on objects, by striking objects and by doors. A usability test has been designe d to evaluate the usability of explorative links in hyper videos. We are going to present the results of this usability test in this paper.

Calle Lejdfors Department of Computer Science, Lund University, PO Box, Lund, Sweden Researcher

Image processing is an area with many computat ionally demanding algorithms. When implementing an algorithm the programmer has to make the choice of either using a high-level language, thereby gaining rapid development at the expense of run-time pe rformance. Or, using a lower level language, having higher run-time performance but also a higher implementation cost. In th is paper we present PyGPU, an embedded language that enables image processing al gorithms to be written in the high-level, object- oriented language Python. PyGPU functions are comp iled to execute on the graphics processing unit (GPU) present on modern graphics cards, a streaming processor capable of speeds more than a magnitude higher than those of current generation CPUs. We demonstrate a number of common image processing algorithms, showing how th ese can be implemented succinctly and clearly using high-level abstractions, while at the same time achieving performance close to theoretical peak figures.

Sarah Powell, Frank Keenan, Kevin McDaid Dundalk Institute of Technology, Ireland Researcher

The importance of good Requirements Engineering (RE) is repeatedly highlighted with many reports indicating how failure in this area contributes greatly to overall project failure. Agile Methods (AMs) have emerged as an alternative to traditional methods for software development. AMs recognize the failure rates of previous projects and promote increas ed collaboration with the customer as one of its main values throughout development. However, probl ems have been reported with the use of the most popular AMs in the area of requireme nts elicitation particularly with an over reliance on a customer and lack of elicitation guidelines. This paper describes a development pr ocess that combines personas, as used in Interaction Design, w ith eXtreme Programming (XP), the most popular AM, to overcome the problem. To investigate the value of this process a case study was conducted in which this process was used in the development of an internet application by a small team. The main findings are that the process used provided benefits but also threw up one or two other problems of its own.

Huihai Lu, John C. Woods, Mohammed Ghanbari Department of Electronic

In this paper, we present a novel region-based imag e analysis platform. With a human in the loop, it provides an efficient method for object extraction, image segmentation, and filtering. The region space is organised into a Binary Partition Tree represen tation where small homogenous regions are successively merged. The hindsight of the merging process is th erefore stored within the tree structure and the evolutions from the seed to root nodes are studied. By analysing these evolutions, discontinuities caused by the merging of heterogeneous regions are identified and the corresponding tree nodes short listed. These nodes indicate salient details within the image and from them tree simplification and region based filtering becomes possible. Given a simpler version of the original tree, manually assisted object extraction and image segmentation can be easily achiev ed and the experimental results show that our method facilitates the extraction of semantic content from the image.

Pedro Isaías

Editorial preface for Volume 2, Issue 1 of the IADIS International Journal on Computer Science and Information Systems (IJCSIS). This issue brings together peer-reviewed original research contributions covering the wide spectrum of Information Systems, Artificial Intelligence, Software Engineering, and Digital Transformation.