Abstract

One of the newest technologies in the programming world is XAML-an XML language used to write applications on the Windows Presentation Foundation (WPF) and Windows workflow. In WPF, XAML is used as a user interface markup language to define UI elements, data binding, and other features. In WF, XAML is used to describe potentially long-running declarative logic, such as those created by process modeling tools and rules systems. XAML is deliberated as a more efficient method of developing application user interfaces. The specific advantage of XAML is that it is a completely declarative language. In a declarative programming, the designer describes the behavior and integration of components without the use of procedural programming. Because of XAMLs Object — Oriented nature, elements and attributes map to classes and properties in the underlying APIs. Anything that is created or implemented in XAML can be expressed using a more traditional .NET language, such as C# or Visual Basic .NET.

Abstract

Time synchronization is crucial for Wireless Sensor Network (WSNs) in performing a number of fundamental operations such as data co-ordination, Power management, Security and localization. The Pairwise Broadcast Synchronization (PBS) protocol was recently proposed to minimize the number of timing messages required for global network synchronization, which enables the design of highly energy-efficient WSNs. However, PBS requires all nodes in the network to lie within the communication ranges of two leader nodes, a condition which might not be available in some applications. This paper proposes an extension of PBS to the more general class of sensor networks. Based on the hierarchical structure of the network, an energy-efficient pair selection algorithm is proposed to select the best pairwise synchronization sequence to reduce the overall energy consumption. It is shown that in a multicluster networking environment, PBS requires a far less number of timing messages than other well-known synchronization protocols and incurs no loss in synchronization accuracy. Moreover, the proposed scheme presents significant energy savings for densely deployed WSNs.

Abstract

There are many computer, communication and manufacturing systems which give rise to models where a system bounded or unbounded queue evolves in an environment that changes state from time to time. Multi server system models are important because of their extensive applications in modeling multiprocessors, transaction processing systems, nodes in communication networks. In this paper the performance measures of heterogeneous multiprocessors system with various repair strategies, serving a stream of arriving jobs is considered. The queuing capacity can be bounded or unbounded. Particular attention is paid on development of such systems and solved for exact performability measures.

Abstract

A Mobile Ad Hoc Network (MANET) is a temporary infrastructureless network, formed by a set of mobile hosts that dynamically establish their own network without relying on any central administration. Mobile ad hoc networking works properly only if the participating nodes cooperate in routing and forwarding. However, performing network functions consumes energy and other resources. To save its energy a node may behave selfishly and uses the forwarding service of other nodes without correctly forwarding packets for them. These nodes must be identified and excluded from the cooperative part of the network, as they only consume resources and don’t contribute to the infrastructure. In MANET’s routing misbehavior can severely degrade the performance at the routing layer. Specifically, nodes may participate in the route discovery and maintenance process but refuse to forward data packets.

This paper surveys the most important selfishness detection and prevention methods that have been introduced, providing a comprehensive comparison between the different proposed schemes.

Abstract

In this paper we provide a framework and analysis that enables the rapid development of applications using non-standard input and datum from various devices, and making the data from the device available on a web server in XML format and then accessing the data from a flash based widget in creating data visualizations.

The discussion will take into account a special case of construction of “FlashGraph” in a yahoo based widget format that uses the XML data generated by the sensor devices installed for monitoring domestic electricity consumption. Flash is chosen as programming language since it can be used for quickly assembling web applications and creating widget. We overcome the difficulties of Flash to access external devices and process the data generated by introducing a very generic concept:

The XML information generated by input devices is transferred to a PC where a program collects them, interprets them and makes them available on a web server. The flash widget component can now access the data that is stored in XML format and directly use it in the application.

Abstract

Fingerprints are today the most widely used biometric features for personal identification. With the increasing usage of biometric systems the question arises naturally how to store and handle the acquired sensor data. In this context, the compression of these data may become imperative under certain circumstances due to the large amounts of data involved. In distributed biometric systems, the data acquisition stage is often dislocated from the feature extraction and matching stage. In such environment the sensor data have to be transferred via a network link to the respective location, often over wireless channels with low bandwidth and high latency. Therefore, a minimization of the amount of data to be transferred is highly desirable, which is achieved by compressing the data before transmission. When a typical fingerprint card is scanned at 500 dpi, with 8 bits/pixel, it results in about 10Mb of data. For 200 million cards, the total size of the digitized collection would be more than 2000 terabytes. Fingerprint images are routinely sent between law enforcement agencies. Overnight delivery of the actual card is too slow and risky, and sending 10 Mb of data through a 9600 baud modem takes about three hours.

Standard methods for still noise-free, image coding are applied in various domains. Spatial image coding technique is basic method as applied in the pixel-domain of the image. Fourier transform methods, is widely used in practice. Today the best known image compression techniques are the JPEG2000 and the SPIHT algorithms. The fractal transform was viewed in the signal processing community as a computationally expensive and limited technique that only works when the image exhibits a high degree of self-similarity. In this paper, a novel approach that reduces the computational complexity of the standard fractal transform. We propose a fast no-search fractal image coding algorithm based on a modified gray-level transform. To improve the possibility of successful matching for a range block and a domain block, we introduce a modified gray level transform with more transform parameters to encode the blocks. In this work we are using two gray-level transforms, one for the parent blocks and other for the child blocks to speed up the encoding time.

Abstract

This paper presents a robust image watermarking scheme for multimedia copyright protection. We propose a watermarking algorithm for digital image based on DWT and SVD by choosing a region of interest and embedding the watermark in the same. The region for choosing a region of interest is an area which contains important information and should be sent through media with out any distortions and attacks. Image quality is checked out with a number of widely used metrics such as PSNR, Normalized correlation. The work is based on this algorithm, demonstrates that the watermarking is robust to the common signal processing techniques including JPEG compressing noise, median filter, Gaussian Blur and Gaussian noise. Experimental results show that the DWT-SVD watermarking scheme is more robust than the DWT method.

Abstract

The authors of this paper consider the problem of conserving energy in a single node in a wireless sensor network by turning off the node's radio for periods of a fixed time length. While packets may continue to arrive at the node's buffer during the sleep periods, the node cannot transmit them until it wakes up. The objective is to design sleep control laws that minimize the expected value of a cost function representing both energy consumption costs and holding costs for backlogged packets. We consider a discrete time system with a Bernoulli arrival process. In this setting, we characterize optimal control laws under the finite horizon expected cost and infinite horizon expected average cost criteria.

Abstract

A real-time operating system (RTOS) supports applications that must meet deadlines in addition to providing logically correct results. This paper reviews pre-requisites for a real-time scheduler in RTOS to be POSIX 1003.1b compliant and scheduling in RTOS. A comparison of the schedulers is presented. We survey the prominent research oriented schedulers and outline steps in system implementation of parametric scheduler for RTOS.

Workstations and personal computers are increasingly being used for applications with real-time characteristics such as speech understanding and synthesis, media computations and I/O, and animation, often concurrently executed with traditional non-real-time workloads. This paper also presents a system that can schedule multiple independent activities. Activities can obtain minimum guaranteed execution rates with application-specified reservation granularities via CPU Reservations. We conclude by discussing the results of the survey and suggest future research directions in the field of scheduler for RTOS.