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This paper describes approaches used by web search tools to communicate with users. With respect to different kinds of information resources, we examine interactive interfaces that use textual queries, tag-focused navigation, hyperlink navigation, visual features, etc. Among others, we introduce the design vision and describe the implementation of a visual-interface based on concepts of query token network and the WordNet ontology.

KineSpell2, a digital game-based learning application, is developed to maximise the learning of spelling. It provides an enjoyable environment that motivates students to learn. The purpose of this research is to establish the acceptability of the Wii Remote as a wireless controller of KineSpell2 through the Controller's Learnability, User Satisfaction and Ease of Use. The acceptability test result suggests that using the Wii Remote as a game controller in an educational context can provide an enjoyable environment with a high acceptability rating.

The limited amount of energy in wireless sensor networks has always been a key topic. In most previous studies regarding multi-sink wireless sensor networks, the network loading is usually regulated by periodically or dynamically redirecting the data flow to different sinks in order to extend the overall life-time of the network and enhance network availability or data delivery. Since sending data to a distant sink consumes much more overall energy, the gain of data delivery should be evaluated against the sacrifice of energy consumption. In this paper, a quantised model is proposed to evaluate the tradeoff between energy consumption and data delivery under non-uniform events triggered by the network. The tradeoff between network availability and energy consumption is to be analysed, and the corresponding results of the simulation will be included.

Nowadays, searching is the most common task performed on the Web. However, the Web searching is especially difficult for beginners when they try to utilise keyword query language. Subsequently, beginners usually try to find information with ambiguous queries. Users then receive non-relevant information in response to such queries. Our goal is to make the search process more convenient for them. We assume that the top ranked pages returned are relevant to the user’s query. On these pages, we find the most important synonyms and hypernyms for the terms of the user query, utilising Japanese WordNet. We combine the aforementioned terms together and a new expanded query is then submitted to the search engine. These operations are done automatically by our prototype. This makes the Web searching process easier for beginners. The experimental results showed that our query expansion technique can improve search performance and has also advantages over what – traditional methods of searching

Extensible dependency grammar (XDG) is a modern formalism for declaring dependency relations between lexical entries, generally used to construct natural language parsers. This work discusses how XDG can be used to build computer-assisted language learning instruments, such as a context-sensitive dictionary, a cases and prepositions learning tool, and a grammar checking module. The paper outlines several ideas currently being researched by the author and his colleagues, and some of the current experiments.

This paper proposes a distributed, lightweight and efficient method for the detection of attacks against data traffic flow. It was designed for wireless sensor networks (WSNs), which contain a large number of static sensor nodes that periodically transmit the sensed data. The intrusion detection scheme is based on analysis of the incoming traffic and a fuzzy inference system. During the first stage, a lightweight thresholding technique is applied to the selected traffic attributes – the packet reception rate (PRR) and packet inter-arrival time (IAT) – in a time window of a given length. Then, the fuzzy inference system derives its final conclusion on the basis of both criteria, deciding whether an attack is taking place. The proposed method does not require installation of any additional hardware or extra communication costs. Its computational requirements are negligible, since it is based on lightweight statistical methods. The proposed scheme may be applied to both hierarchical and flat WSNs. The proposed technique was evaluated in Castalia simulator for WSNs, and demonstrated better accuracy in comparison with common algorithms. It may serve as a component of a complex intrusion detection system (IDS).

Ad hoc networks are collections of wireless mobile devices with limited broadcast range and resources, and with no fixed infrastructure. A routing issue is one of the most basic networking issues in ad hoc networks. An adversary can easily palsy the network by attacking the routing protocol. There are some secure routing protocols that have been proposed for ad hoc networking. This paper discusses the critical flaws of a so called Ariadne ad hoc routing protocol. Showing that the security aspects of the Ariadne route discovery algorithm is faulty and vulnerable to attacks, we propose an enhanced route discovery algorithm to overcome these shortages and drawbacks. The proposed method in this paper adds the ability of malicious node detections with this protocol.

Degradation in images is usually undesirable but unavoidable. The most common cause of this is motion. Given only the image degraded by motion blur, blind restoration aims to determine the original unblurred image and the blurring function. This paper proposes an approach to simultaneously determine these two quantities by utilising a reference point spread function (RPSF) as a learning basis in the alternating minimisation cycle. Based on the behaviour of maxima in the presence of blurs and assuming a blurring function support size, RPSF can be extracted from the given degraded image. This implies that learning is not dependent on estimated values and as a result it will not vary as restoration iteration progresses. The cost function is formulated such that spurious colour artefacts can be avoided, and the contour of the piecewise blurring function is also accounted for. Experimental results show that the proposed method is capable of determining an RPSF that closely resembles the actual blur despite the presence of noise and a small image size. Reconstruction with the proposed cost function resulted in better image quality in contrast to other methods.

A knowledge of protein functions is crucial for the development of new drugs, better crops and synthetic biochemicals. To understand the structure-to-function relationship, life-sciences researchers and biologists need to retrieve similar structures from protein databases and classify them into the same protein fold. With technological development the number of determined protein structures increases rapidly, so retrieving structurally similar proteins using current structural alignment algorithms may take hours or even days. Therefore, improving the efficiency of the protein structure retrieval and classification becomes an important research issue. In this paper we present two HMMs (Hidden Markov Models) which provide faster classification of protein structures. Our first method considers secondary structures, while our second method builds a profile of the tertiary structures of protein molecules. We have made a comparison of these two algorithms, and the results showed that by considering the information contained in the protein tertiary structure, a higher precision is achieved. Additionally, we have compared our HMM method based on tertiary structures against an existing method named 3D HMM. This analysis showed that our method is more accurate than 3D HMM.

Software reliability has always been a concern for both software producers and consumers. Because of their role in binary code generation, compilers have a significant impact on software performance. Although many works have been conducted on compilers, little has been done to study their impact on software reliability. Thus, people often face a void of useful knowledge when deciding which compiler to use when developing software to meet a specific reliability target. This paper tries to provide some guidance in compiler selection for users by performing a cross-comparison study on popular C compilers: GCC, Intel, Sun, PGI, LLVM, and Visual Studio. We use Fedora, Mac OS x86, and Windows as our platforms and SPEC CPU2006 benchmark suite as our test set. Our results show that on average, the GCC C compiler is the best for Linux environment, and PGI C compiler is superior to Intel on UNIX based OSs. However Intel shows better performance and VS shows a higher efficiency on Windows OS. Additionally this result is consistent with the user experience based on our survey feedback.

In hierarchical scheduling, a system is organised as a tree of nodes, where each node schedules its child nodes. A node contains tasks and/or subsystems, where a subsystem is typically produced by a development team. Given a system where each part is subcontracted to different developers, they can benefit from hierarchical scheduling by parallel development and simplified integration of subsystems. Each team should have the possibility to test their system before integration. Hence, we show how a node in a hierarchical scheduling tree can be analysed by the Times tool by replacing all interference from nodes with a small set of higher priority tasks. We show an algorithm that can generate these tasks, including their parameters. Furthermore, we use the Times code-generator, in combination with operating system extensions, to generate source code that emulates the scheduling environment for a subsystem at an arbitrary level in the tree. Our experiments include two example systems. In the first case we generate source code for an industrial oriented platform (VxWorks) and conduct a performance evaluation. In the second example we generate source code that emulates the scheduling environment for a video application, running in Linux, and we perform a frame-rate evaluation.

Implementing an algorithm into hardware platforms is generally not an easy task. The algorithm, typically described in a high-level specification language, must be translated into a low-level HDL language. The difference between models of computation (sequential versus fine-grained parallel) limits the efficiency of automatic translation. On the other hand, manual implementation is time-consuming, because the designer must take care of low-level details, and write test benches to test the implementation’s behaviour. This paper presents a global design method, from high level description to implementation. The first step consists of the description of an algorithm as a dataflow program using RVC-CAL language. The next step is the functional verification of this description using a software framework. The final step consists of an automatic generation of an efficient hardware implementation from the dataflow program. The objective is to spend the greater part of the conception time in an open source software platform. We use this method to quickly prototype and generate hardware implementation of a baseline part of the LAR coder, from an RVC-CAL description.

Typically, when a user wishes to minimise the energy consumption for an application running on a handheld device, he/she may choose to set the processor speed to its slowest level. However, our study indicated that due to the processes involved in memory accesses, decreasing the CPU frequency may not always reduce the energy consumption. A critical speed has been defined as the CPU frequency, at which energy consumption can be minimised for a program. It can be used when the user wants to maximise energy saving for the device if performance is a less important issue. In this paper, an energy conservation DVFS algorithm is proposed to achieve this goal. It predicts and applies the critical speed as the target CPU frequency during the program’s execution time. The algorithm relies on a prediction equation that is constructed based on the correlation between the critical speed and the memory access rate. We have implemented the algorithm on the Android operating system. Our results show that both the energy consumption and the performance can be improved than the situation of simply selecting the lowest frequency.

In this paper, Policing Traffic Management (PTM) is applied to improve the Quality of Service (QoS) over an Inter- Vehicular Communications System (IVCS). In Bangkok, Thailand’s capital city, there is a convergence of networks such as Mobile Ad Hoc Networks (MANET), FleetNET, CARNET, BTSNET and other electronic devices. Each network has unique data traffic characteristics. In MANET, most of the traffic comprises of video and voice traffic, BTSNET traffic is data, while CARNET contains both data and video traffic and FleetNET traffic focusses on voice and data. BTSNET can be implemented as regular traffic patterns in order to assist other networks to support traffic delivery by employing these intermediate nodes. However, some particular nodes are congested and the number of packet-drops is rising. This will apparently degrade the QoS of multimedia traffic. The proposed algorithm, PTM, is an extension of the Adaptive Rate Control algorithm (ARC) which mainly improves the QoS performance by adjusting transmission rates based upon traffic priority. Voice will be set as highest, video as medium and data as the lowest priority. The numbers of packet-drop, traffic rate and mean delay time will be collected. The proposed PTM will hold some dropped packets to further retransmit based upon the prearranged priority. NS2 and EZsim Simulations are utilised under both normal and congested situations. Results are outperformed when compared to previous research which is exclusive of the policing scheme.

The IEEE 802.11 based wireless LAN (WLAN) is most widely used for the multimedia and real time communication such as video streaming, Voice over IP (VOIP) video conferencing and other multimedia communications. A Mobile Node (MN) may move from one network to the other network performing a vertical handoff. The problem arises in the continuous data (multimedia traffic) transmission in the existing ISP mesh while frequently handover take place. To maintain the connectivity of an established multimedia traffic between two different networks using mobility management we propose an efficient algorithm which maintain the real time connection as well as preventing the data loss during transition from WLAN to EVDO. We experiment on our proposed algorithm by using a redundant buffer which stores the multimedia data in transition mode and transmits the data of alternate data samples extracted from the original analogous multimedia traffic. When the connection is re-established with the network, the sequential data stored and transmitted from the buffer will keep the communication i.e. multimedia streaming in the real time protocol mode and filtering out the delay caused by inter-frame gap (IFG) enhances the data extraction process.