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This paper presents the conventional and multiband Orthogonal Frequency Division Multiplexing (OFDM) simulation software named Signal Modulation Simulator (SiMiSIM). A simulation system was built with a Graphical User Interface (GUI) to provide a more user friendly interface than contemporary or command line interfaces. Three basic frequency modulation techniques were made available in SiMiSIM: Binary Phase Shift Keying (BPSK), Quadrature Phase-Shift Keying (QPSK) and Quadrature Amplitude Modulation (QAM). Each of the signals had to face Forward Error Correction (FEC) encoder to enhance the signal robustness at the receiver end. The simulation was able to simulate Bit Error Rate (BER) and Power Spectral Density (PSD) for research purposes as well as educational purposes.

In the environment of Mobile Ad-hoc Networks (MANETs), devices can collaborate under the service-oriented architecture (SOA). However, as MANETs are infrastructureless, devices may move randomly and join and leave the network at any time which leads to a permanently changing topology of the network. What adds to the unpredictability of the network is the limited resource of the nodes, including battery power, processing capacity and memory limit which are common problems for mobile devices. All these features pose a potential risk of failure to the process of service execution. Therefore, service recovery is indispensable to guarantee the success rate when the service execution plan cannot be conducted as the user expects. In this paper, we proposed a novel strategy of service execution and service recovery. By employing additional control messages, the point of fault can be quickly acknowledged by the closest device which will then take charge of service recovery. Using the distributed service cache maintained by each node in the network, a back-up service execution plan will be elected promptly. The simulation shows that our strategy can effectively reduce the response time and increase the success rate of service execution.

With the rapid development in Web 2.0 application services, tags are used as useful metadata in social collaborative annotation systems. In this paper, we propose a collaborative approach for expanding tag neighbours and investigate the use of a spectral clustering algorithm to deal with issues of ambiguity and redundancy of tags. The algorithm could effectively filter out noisy tag neighbours, and thus obtain more appropriate recommendations for users. Experiments have been conducted on two real world datasets: “MovieLens” and “M-Eco system”, to compare our proposed approach with the traditional collaborative filtering approaches and naive tag neighbours expansion approaches in terms of precision. The results showed the effectiveness and superiority of our proposed method against the traditional approaches, which demonstrate that our approach could considerably improve the performance of recommendation.

This paper is presenting an idea of applying the Scrum framework in the IT service support domain. Scrum framework is mainly used with conjunction of other agile methods in software development domain, but almost, no reporting for its usage in the support of that software, except in few cases. Scrum framework can be applied at small, medium, and as well as large organizations, and companies. We expect that Scrum can change the IT service support from cost center into revenue and more value added center. We also expect that Scrum framework can change some companies’ profiles. The results achieved in a reallife example are prosperous and fruitful, as we will present in this paper a reported real-life example of applying the Scrum framework in the IT Service Support along with the results achieved. In the case study we present here in the previous work section the framework was applied in a horizontal fashion. We will propose a vertical way of the framework application, and another new idea of dynamic Sprint planning along some of the expected results. As this idea is newly applied to that domain, so the horizontal, the vertical framework application ways, or the dynamic sprint planning idea will need more experimenting, and documenting in order to reach a solid conclusions, and results. We will recommend some of the future work that need to be done in that domain, and scope in order to document

BPMN is widely used in Model Drive Architectures (MDA) for enterprise-scale solutions. In this paper, we shall realise an executional platform for MDA frameworks using BPMN. We transform BPMN into an executional framework using Orc [1]. Orc is a web orchestration language that provides uniform access to computational services, including distributed communication and data manipulation. The interesting features of Orc are its capability to cleanly specify patterns like multimerge, discriminator, arbitrary cycles and several multiple instances, etc.. It supports the realisation of the MapReduce paradigm for distributed computing, and thus provides a powerful MDA approach for business analysts to express their solutions. The framework enables the creation/simulation of mock scenarios and the use of verification/validation/debugging in an integrated way. In this paper, we describe a transformation of BPMN core elements to Orc. We use a graph-based approach where a Business Process Diagram (BPD) diagram is validated and then converted into a set of Orc computation structures. We describe the transformations along with an implementation and illustrate the process with an example.