bluuebunny/crossref_metadata_2025 huggingface dataset:
Ensuring Serializability for Mobile-Client Data Caching
Authors: Parker Shin , Chen Zhengxin
Published: May 2011

Data management in mobile computing has emerged as a major research area, and it has found many applications. This research has produced interesting results in areas such as data dissemination over limited bandwidth channels, location-dependent querying of data, and advanced interfaces for mobile computers (Barbara, 1999). However, handling multimedia objects in mobile environments faces numerous challenges. Traditional methods developed for transaction processing (Silberschatz, Korth & Sudarshan, 2001) such as concurrency control and recovery mechanisms may no longer work correctly in mobile environments. To illustrate the important aspects that need to be considered and provide a solution for these important yet “tricky” issues in this article, we focus on an important topic of data management in mobile computing, which is concerned with how to ensure serializability for mobile-client data caching. New solutions are needed in dealing with caching multimedia data for mobile clients, for example, a cooperative cache architecture was proposed in Lau, Kumar, and Vankatesh (2002). The particular aspect considered in this article is that when managing a large number of multimedia objects within mobile client-server computing environments, there may be multiple physical copies of the same data object in client caches with the server as the primary owner of all data objects. Invalid-access prevention policy protocols developed in traditional DBMS environment will not work correctly in the new environment, thus, have to be extended to ensure that the serializability involving data updates is achieved in mobile environments. The research by Parker and Chen (2004) performed the analysis, proposed three extended protocols, and conducted experimental studies under the invalid-access prevention policy in mobile environments to meet the serializability requirement in a mobile client/server environment that deals with multimedia objects. These three protocols, referred to as extended server-based two-phase locking (ES2PL), extended call back locking (ECBL), and extended optimistic two-phase locking (EO2PL) protocols, have included additional attributes to ensure multimedia object serializability in mobile client/server computing environments. In this article, we examine this issue, present key ideas behind the solution, and discuss related issues in a broader context.
Extended Entity Relationship Modeling
Authors: Bagui Sikha
Published: May 2011

With the rising complexity of database applications, the basic concepts of Entity-Relationship (ER) modeling (as originally developed by Chen, 1976) were no longer sufficient. So the basic ER model was extended to include generalizations and specializations (Bagui & Earp, 2003; Elmasri & Navathe, 2003) and the concept of categories (Elmasri, Weeldreyer & Hevner, 1985). An ER model which includes all the concepts of the original ER model and the additional concepts of generalizations/specializations and categories is often referred to as the Extended ER (EER) model (Elmasri & Navathe, 2003). In this short paper, we shed some light on these relationship concepts, concepts that database designers often find difficult to model directly (Engels et al., 1992/1993). We also discuss the mapping rules for generalizations/specializations and categories. Important contributions in this area are also reported in (Elmasri et al., 1985; Markowitz & Shoshani, 1992; Dey, Storey & Barron, 1999; Wiederhold & Elmasri, 1980). Song, Evans, and Park (1995) also give a good comparative analysis of other types of ER diagrams and their notations.
Metric Databases
Authors: Chávez Edgar , Navarro Gonzalo
Published: May 2011

The advent of the digital age creates an increasing interest to search for information in large, unstructured repositories containing textual and multimedia data. Retrieval from those repositories requires more powerful query languages, which exceed the querying capabilities of traditional database technologies. The metric space model, described herein, is an extension of the exact searching paradigm aiming to cope with the new requirements.
Modeling and Querying Temporal Data
Authors: Tansel Abdullah Uz
Published: May 2011

Databases in general store current data. However, the capability to maintain temporal data is a crucial requirement for many organizations and provides the base for organizational intelligence. A temporal database has a time dimension and maintains time-varying data (i.e., past, present, and future data). In this article, we focus on the relational data model and address the subtle issues in modeling temporal data, such as comparing database states at two different time points, capturing the periods for concurrent events, and accessing to times beyond these periods, handling multivalued attributes, coalescing, and restructuring temporal data (Gadia 1988, Tansel & Tin, 1997). Many extensions to the relational data model have been proposed for handling temporal data.
Multimedia Databases
Authors: Hentea Mariana
Published: May 2011

The Internet and technologies such as high-capacity storage devices, broadband telecommunications systems, and multimedia development software systems have accelerated the development of new applications based on the use of multimedia database systems. A multimedia database is a repository of different data objects (text, numeric values, Boolean values, dates, graphical images, video clips, and sound files). Examples of applications based on multimedia databases include news and stock market information on demand; movies on demand; home shopping; medical systems; trademark, patent, and copyright databases; geographic information systems (GIS); weather forecasting; Computer Aided Design (CAD) systems; architectural design; fabric and fashion design; interior design; photographic libraries; art gallery and museum management; law enforcement; criminal investigations; military reconnaissance and surveillance; scientific experiments; and educational systems.
Natural Language Front-End for a Database
Authors: Galitsky Boris
Published: May 2011

Whatever knowledge a database contains, one of the essential questions in its design and usability is how its users will interact with it. If these users are human agents, the most ordinary way to query a database would be in the natural language (Gazdar, 1999; Popescu, Etzioni, & Kautz, 2003; Sabourin, 1994). Natural language question answering (NL Q/A), wherein questions are posed in a plain language, may be considered the most universal but not always the best (i.e., fastest) way to provide the information access to a database. One should be aware that approaches to data access, such as visualization, menus and multiple choice, FAQ lists, and so forth, have been successfully employed long before the NL Q/A systems came into play. In the following, I discuss situations in which a particular information access approach is optimal.
Open Source Software and Information Systems on the Web
Authors: Cartelli Antonio
Published: May 2011

Databases and systems for their management are today more and more important for individual and corporate applications. Furthermore the spreading of the Internet has made possible the achievement of centralized information systems, accessible from everywhere on the Net, both for querying data and for managing them.
Optimization of Continual Queries
Authors: Khan Sharifullah
Published: May 2011

Recent advances in the technologies have made it possible to access information from Internet-scale distributed data sources (Florescu, Levy & Mendelzon, 1998). However, finding the right information at the right time is difficult. Update monitoring (Seligman et al., 2000) is a technology that gathers relevant information and forwards it to users in a timely way. Continual queries (CQs) (Chen et al., 2000; Khan & Mott, 2002a; Liu, Pu & Tang, 1999, 2000) provide a significant toolkit for update monitoring. They are persistent queries that are issued once and then are run at regular intervals or when data change until a termination condition is satisfied. They are then removed from the system. They relieve users from having to revisit Web sites or other data sources and reissue their queries frequently to obtain new information that match their queries. A CQ is a typical SQL query having additional triggering and termination conditions. CQs are of two types: change-based and time-based. An example of a CQ is “notify me in the next six months whenever the Microsoft stock price drops by more than 5% from today level.”
Path-Oriented Queries and Tree Inclusion Problem
Authors: Chen Yangjun
Published: May 2011

With the rapid advance of the Internet, management of structured documents such as XML documents has become more and more important (Marchiori, 1998). As a simplified version of SGML, XML is recommended by W3C (World Wide Web Consortium, 1998a; World Wide Web Consortium, 1998b) as a document description meta-language to exchange and manipulate data and documents on the WWW. It has been used to code various types of data in a wide range of application domains, including a Chemical Markup Language for exchanging data about molecules, the Open Financial Exchange for swapping financial data between banks and banks and customers, as well as a Geographical Markup Language for searching geographical information (Bosak, 1997; Zhang & Gruenwald, 2001). Also, a growing number of legacy systems are adapted to output data in the form of XML documents.
Preferred Repairs for Inconsistent Databases
Authors: Greco Sergio , Sirangelo Cristina , Trubitsyna Irina , Zumpano Ester
Published: May 2011

The objective of this article is to investigate the problems related to the extensional integration of information sources. In particular, we propose an approach for managing inconsistent databases, that is, databases violating integrity constraints. The problem of dealing with inconsistent information has recently assumed additional relevance as it plays a key role in all the areas in which duplicate information or conflicting information is likely to occur (Agarwal et al., 1995; Arenas, Bertossi & Chomicki, 1999; Bry, 1997; Dung, 1996; Lin & Mendelzon, 1999; Subrahmanian, 1994).
Query Processing for RDF Data
Authors: Stuckenschmidt Heiner
Published: May 2011

The World Wide Web today is a huge network of information resources which was built in order to broadcast information for human users. Consequently, most of the information on the Web is designed to be suitable for human consumption: the structuring principles are weak, many different kinds of information co-exist, and most of the information is represented as free text.
Replication Mechanisms Over a Set of Distributed UDDI Registries
Authors: Maamar Zakaria
Published: May 2011

This paper presents a research initiative, which aims at developing replication mechanisms for the dynamic management of the content of several Universal Description, Discovery, and Integration (UDDI) registries (Curbera et al., 2003). These replication mechanisms are intended to be deployed in an environment of Web services (Papazoglou & Georgakopoulos, 2003). By content of an UDDI registry, we mean the announcements of Web services that providers post on the UDDI registry.
Replication Methods and Their Properties
Authors: Frank Lars
Published: May 2011

The most important evaluation criteria for replication methods are availability, performance, consistency, and costs. Performance and response time may be improved by substituting remote data accesses with local data accesses to replicated data. The availability of the system can be increased by using replicated data in case a local failure or disaster should occur. The major disadvantages of data replication are the additional costs of updating replicated data and the problems related to managing the consistency of the replicated data. Tables 1 and 2 give an overview of the evaluation of the replication methods described in this article. Frank (1999) described how such replication overviews may be used to optimize databases in practice. This article evaluates many more replication methods and therefore, it is possible to optimize even more. However, the evaluation criteria previously described have to be subdivided to illustrate the different properties of the different replication methods.
Service Mechanism Quality for Enhanced Mobile Multimedia Database Query Processing
Authors: Zhang Yanpu , Chen Zhengxin
Published: May 2011

Among the challenges of multimedia and mobile computing, providing a mechanism for data retrieval in multimedia databases under wireless mobile environments is one of the most difficult issues (Shih, 2001). Up to now, the fundamental technologies that are specialized for wireless mobile, multimedia environments are not mature in object-oriented, object-relational, as well as relational databases (Hillborg, 2002; Ramakrishnan & Gehrke, 2003; Watson, 2004). An important issue is how to ensure quick query response for the users. If a user found out that the retrieved multimedia object is neither interesting nor useful after it is displayed, then the time and bandwidth used for transmitting the multimedia objects have already been wasted. In order to save precious time and expensive bandwidth, it could be a good idea to let users browse objects at an acceptable resolution without paying much attention to the details or at the limited device display capability. This article presents a novel concept to deal with this problem by making use the concept of quality of service (QoS) to achieve adaptive query processing. In general, traditional QoS management is defined as the necessary supervision and control to ensure that the desired quality of service properties are attained and sustained, which applies both to continuous media interactions and to discrete interactions (Chalmers & Sloman, 1999). QoS thus consists of a set of specific requirements for a particular service provided by a network to users. However, little work has been done in extending QoS principles to multimedia data management in wireless network environments.
Set Valued Attributes
Authors: Ramasamy Karthikeyan , Deshpande Prasad M.
Published: May 2011

About three decades ago, when Codd (1970) invented the relational database model, it took the database world by storm. The enterprises that adapted it early won a large competitive edge. The past two decades have witnessed tremendous growth of relational database systems, and today the relational model is by far the dominant data model and is the foundation for leading DBMS products, including IBM DB2, Informix, Oracle, Sybase, and Microsoft SQL server. Relational databases have become a multibillion-dollar industry.
Similarity Search in Time Series Databases
Authors: Kontaki Maria , Papadopoulos Apostolos N. , Manolopoulos Yannis
Published: May 2011

In many application domains, data can be represented as a series of values (time series). Examples include stocks, seismic signals, audio, and many more. Similarity search in time series databases is an important research direction. Several methods have been proposed in order to provide algorithms for efficient query processing in the case of static time series of fixed length. Research in this field has focused on the development of effective transformation techniques, the application of dimensionality reduction methods, and the design of efficient indexing schemes. These tools enable the process of similarity queries in time series databases. In the case where time series are continuously updated with new values (streaming time series), the similarity problem becomes even more difficult to solve, since we must take into consideration the new values of the series. The dynamic nature of streaming time series makes the methods proposed for the static case inappropriate. To attack the problem, significant research has been performed towards the development of effective and efficient methods for streaming time series processing. In this paper, we introduce the most important issues concerning similarity search in static and streaming time series databases, presenting fundamental concepts and techniques that have been proposed by the research community.
Spatio-Temporal Indexing Techniques
Authors: Vassilakopoulos Michael , Corral Antonio
Published: May 2011

Time and space are ubiquitous aspects of reality. Temporal and spatial information appear together in many everyday activities, and many information systems of modern life should be able to handle such information. For example, information systems for traffic control, fleet management, environmental management, military applications, local and public administration, and academic institutions need to manage information with spatial characteristics that change over time, or in other words, spatio-temporal information. The need for spatio-temporal applications has been strengthened by recent developments in mobile telephony technology, mobile computing, positioning technology, and the evolution of the World Wide Web.
Symbolic Objects and Symbolic Data Analysis
Authors: Nigro Héctor Oscar , González Císaro Sandra Elizabeth
Published: May 2011

Today’s technology allows storing vast quantities of information from different sources in nature. This information has missing values, nulls, internal variation, taxonomies, and rules. We need a new type of data that allow us to represent the complexity of reality, maintaining the internal variation and structure (Bock & Diday, 2000; Diday, 2002, 2003).
Syntactical and Semantical Correctness of Pictorial Queries for GIS
Authors: Ferri Fernando , Rafanelli Maurizio
Published: May 2011

One of the main topics in geographical information systems (GIS) research concerns the definition of high level visual query languages (Chrisman, 2002; Laurini & Thompson, 1992). This arises from the need to provide the user with a visual interactive tool for data manipulation and retrieval that is independent of the data’s physical organization. The use of standard query languages for spatial data handling (Rigaux, Scholl, & Voisard, 2001; Shekhar et al. 1999) has been hindered by the lack of appropriate language support. In fact, in visual query languages for GIS, a query can lead to multiple interpretations (Favetta & Aufaure-Portier, 2000).
Transactional Support for Mobile Databases
Authors: Leong Hong Va
Published: May 2011

With the widespread deployment of wireless communication infrastructure in the past decade, accessing information online while a client is on the move becomes a concrete possibility. Such a computing environment is often referred to as a mobile environment (Imielinski & Badrinath, 1994). A typical group of applications that deserve strong support under the mobile environment would be database access. Database systems that support operations initiated from mobile clients are referred to as mobile databases (Leong & Si, 1997). We have witnessed a tremendous growth in mobile database research in the past ten years. Yet only the most primitive results have been incorporated in real applications. This is due to the additional dimensions of complexity that the mobile environment has introduced, beyond standard client/server computing environment.
Agent Frameworks
Authors: Zwitserloot Reinier , Pantic Maja
Published: May 2011

Software agent technology generally is defined as the area that deals with writing software in such a way that it is autonomous. In this definition, the word autonomous indicates that the software has the ability to react to changes in its environment in a way that it can continue to perform its intended job. Specifically, changes in its input channels, its output channels, and the changes in or the addition or removal of other agent software should cause the agent to change its own behavior in order to function properly in the new environment. In other words, the term software agent refers to the fact that a certain piece of software likely will be able to run more reliably without user intervention in a changing environment compared to similar software designed without the software agent paradigm in mind. This definition is quite broad; for example, an alarm clock that automatically accounts for daylight savings time could be said to be autonomous in this property; a change in its environment (namely, the arrival of daylight savings time) causes the software running the clock to adjust the time it displays to the user by one hour, preserving, in the process, its intended function—displaying the current time. A more detailed description of agent technology is available from Russel and Norvig (2003).
Application Service Providers
Authors: Morabito Vincenzo , Provera Bernardino
Published: May 2011

Until recently, the development of information systems has been ruled by the traditional “make or buy” paradigm (Williamson, 1975). In other words, firms could choose whether to develop particular applications within their organizational structure or to acquire infrastructures and competences from specialized operators. Nevertheless, the Internet’s thorough diffusion has extended the opportunities that firms can rely upon, making it possible to develop a “make, buy, or rent” paradigm. Application service providers represent the agents enabling this radical change in the IS scenario, providing clients with the possibility to rent specifically-tailored applications (Morabito, 2001; Pasini, 2002).
Content Repurposing for Small Devices
Authors: Rowe Neil C.
Published: May 2011

Content repurposing is the reorganizing of data for presentation on different display hardware (Singh, 2004). It has been particularly important recently with the growth of handheld devices such as personal digital assistants (PDAs), sophisticated telephones, and other small specialized devices. Unfortunately, such devices pose serious problems for multimedia delivery. With their tiny screens (150 by 150 for a basic Palm PDA or 240 by 320 for a more modern one, vs. 640 by 480 for standard computer screens), one cannot display much information (i.e., most of a Web page); with their low bandwidths, one cannot display video and audio transmissions from a server (i.e., streaming) with much quality; and with their small storage capabilities, large media files cannot be stored for later playback. Furthermore, new devices and old ones with new characteristics have been appearing at a high rate, so software vendors are having difficulty keeping pace. So some real-time, systematic, and automated planning could be helpful in figuring how to show desired data, especially multimedia, on a broad range of devices.
Designing Web-Based Hypermedia Systems
Authors: Lang Michael
Published: May 2011

Although its conceptual origins can be traced back a few decades (Bush, 1945), it is only recently that hypermedia has become popularized, principally through its ubiquitous incarnation as the World Wide Web (WWW). In its earlier forms, the Web could only properly be regarded a primitive, constrained hypermedia implementation (Bieber & Vitali, 1997). Through the emergence in recent years of standards such as eXtensible Markup Language (XML), XLink, Document Object Model (DOM), Synchronized Multimedia Integration Language (SMIL) and WebDAV, as well as additional functionality provided by the Common Gateway Interface (CGI), Java, plug-ins and middleware applications, the Web is now moving closer to an idealized hypermedia environment. Of course, not all hypermedia systems are Web based, nor can all Web-based systems be classified as hypermedia (see Figure 1). See the terms and definitions at the end of this article for clarification of intended meanings. The focus here shall be on hypermedia systems that are delivered and used via the platform of the WWW; that is, Web-based hypermedia systems.
Distance Education Delivery
Authors: Wright Carol
Published: May 2011

The term distance education is used to describe educational initiatives designed to compensate for and diminish distance in geography or distance in time. The introduction of technology to distance education has fundamentally changed the delivery, scope, expectations, and potential of distance education practices. Distance education programs are offered at all levels, including primary, secondary, higher, and professional education. The earliest antecedents of distance education at all levels are found worldwide in programs described most commonly as correspondence study, a print-dependent approach prolific in geographic areas where distance was a formidable obstacle to education. As each new technology over the last century became more commonly available, it was adopted by educational practitioners eager to improve communication and remove barriers between students and teachers.
E-Commerce and Usability
Authors: Singh Shawren
Published: May 2011

The term “Electronic Commerce” (EC) conjures various interpretations. Figure 1.1 shows some of the different types of EC, of which there are many, such as Business-to-Business (B2B); Business-to-Consumer (B2C); Consumer-to-Business (C2B); Consumer-to-Consumer (C2C); People-to-People (P2P); non-business EC; intrabusiness (organisational) EC; business-to-employees (B2E); government-to-citizen (G2C); exchange-to-exchange (E2E); collaborative commerce; ultimate commerce (u-commerce) and mobile commerce (m-commerce).
Ethernet Passive Optical Networks
Authors: Freire Mário M. , Monteiro Paulo P. , da Silva Henrique J.A. , Ruela Jose
Published: May 2011

Recently, Ethernet Passive Optical Networks (EPONs) have received a great deal of interest as a promising cost-effective solution for next-generation high-speed access networks. This is confirmed by the formation of several fora and working groups that contribute to their development; namely, the EPON Forum (http://www.ieeecommunities.org/epon), the Ethernet in the First Mile Alliance (http://www.efmalliance.org), and the IEEE 802.3ah working group (http://www.ieee802.org/3/efm), which is responsible for the standardization process. EPONs are a simple, inexpensive, and scalable solution for high-speed residential access, capable of delivering voice, high-speed data, and multimedia services to end users (Kramer, Mukherjee &Maislos, 2003; Kramer & Pesavento, 2002; Lorenz, Rodrigues & Freire, 2004; Pesavento, 2003; McGarry, Maier & Reisslein, 2004). An EPON combines the transport of IEEE 802.3 Ethernet frames over a low-cost and broadband point-to-multipoint passive optical fiber infrastructure connecting the Optical Line Terminal (OLT) located at the central office to Optical Network Units (ONUs), usually located at the subscriber premises. In the downstream direction, the EPON behaves as a broadcast and select shared medium, with Ethernet frames transmitted by the OLT reaching every ONU. In the upstream direction, Ethernet frames transmitted by each ONU will only reach the OLT, but an arbitration mechanism is required to avoid collisions.
From Communities to Mobile Communities of Values
Authors: McManus Patricia , Standing Craig
Published: May 2011

The discussion around the impact of information communication technologies in human social interaction has been the centre of many studies and discussions. From 1960 until 1990, researchers, academics, business writers, and futurist novelists have tried to anticipate the impact of these technologies in society, in particular, in cities and urban centres (Graham, 2004). The views during these three decades, although different in many aspects, share in common a deterministic view of the impact of ICT on cities and urban centres. They all see ICT influence as a dooming factor to the existence of cities. These authors have often seen ICT as a leading factor in the disappearance of urban centres and/or cities (Graham; Marvin, 1997; Negroponte, 1995). According to Graham, these views tend to portray ICT impact without taking into consideration the fact that old technologies are not always replaced by newer ones; they can also superimpose and combine into to something else. These views also have generally assumed that the impact of ICT would be the same in all places and have not accounted for geographic differences that could affect the use of information communication technologies.
Information Systems Strategic Alignment in Small Firms
Authors: Cragg Paul B. , Todorova Nelly
Published: May 2011

The concept of “alignment” or “fit” expresses an idea that the object of design—for example, an organization’s structure or its information systems (IS)—must match its context to be effective (Iivari, 1992). More recently, Luftman (2004) has taken this argument one step further and argued that a lack of alignment within an organization will limit the effectiveness of the organization’s business strategies.
Interactive Multimedia Technologies for Distance Education Systems
Authors: Rahman Hakikur
Published: May 2011

Information is typically stored, manipulated, delivered and retrieved using a plethora of existing and emerging technologies. Businesses and organizations must adopt these emerging technologies to remain competitive. However, the evolution and progress of the technology (object orientation, high-speed networking, Internet, etc.) has been so rapid that organizations are constantly facing new challenges in end-user training programs. These new technologies are impacting the whole organization, creating a paradigm shift that in turn enables them to do business in ways never possible before (Chatterjee & Jin, 1997).
Internet Privacy from the Individual and Business Perspectives
Authors: Stern Tziporah
Published: May 2011

People have always been concerned about protecting personal information and their right to privacy. It is an age-old concern that is not unique to the Internet. People are concerned with protecting their privacy in various environments, including healthcare, the workplace and e-commerce. However, advances in technology, the Internet, and community networking are bringing this issue to the forefront. With computerized personal data files: a. retrieval of specific records is more rapid; b. personal information can be integrated into a number of different data files; and c. copying, transporting, collecting, storing, and processing large amounts of information are easier.
IT Management Practices in Small Firms
Authors: Cragg Paul B. , Suraweera Theekshana
Published: May 2011

Computer based information systems have grown in importance to small firms and are now being used increasingly to help them compete. For example, many small firms have turned to the World Wide Web to support their endeavours. Although the technology that is being used is relatively well understood, its effective management is not so well understood. A good understanding is important as the management of IT is an attribute that has the potential to deliver a sustainable competitive advantage to a firm (Mata, Fuerst, & Barney, 1995). This chapter shows that there is no one accepted view of the term “IT management” for either large or small firms. However, the term “management” is often considered to include the four functions of planning, organising, leading, and controlling. This framework can be applied to small firms and specifically to their IT management practices.
Malware and Antivirus Procedures
Authors: Luo Xin , Warkentin Merrill
Published: May 2011

The last decade has witnessed the dramatic emergence of the Internet as a force of inter-organizational and inter-personal change. The Internet and its component technologies, which continue to experience growing global adoption, have become essential facilitators and drivers in retailing, supply chain management, government, entertainment, and other processes. However, this nearly-ubiquitous, highly-interconnected environment has also enabled the widespread, rapid spread of malware, including viruses, worms, Trojan horses, and other malicious code. Malware is becoming more sophisticated and extensive, infecting not only our wired computers and networks, but also our emerging wireless networks. Parallel to the rise in malware, organizations have developed a variety of antivirus technologies and procedures, which are faced with more challenging tasks to effectively detect and repair current and forthcoming malware. This article surveys the virus and antivirus arena, discusses the trends of virus attacks, and provides solutions to existing and future virus problems (from both technical and managerial perspectives).
Modeling Interactive Distributed Multimedia Applications
Authors: Guan Sheng-Uei
Published: May 2011

In recent years, researchers have tried to extend Petri net to model multimedia. The focus of the research flows from the synchronization of multimedia without user interactions, to interactions in distributed environments (Bastian, 1994; Blakowski, 1996; Diaz, 1993; Guan, 1998; Huang, 1998; Huang, 1996; Little, 1990; Nicolaou, 1990; Prabhakaran, 1993; Prabhat, 1996; Qazi, 1993; Woo, 1994). The issues that concern us are the flexibility and compactness of the model. Petri net extensions have been developed to facilitate user interactions (UI) in distributed environments; however, they require sophisticated pre-planning to lay out detailed schedule changes. In this article, we introduce a Reconfigurable Petri Net (RPN).
Network Intrusion Tracking for DoS Attacks
Authors: Syed Mahbubur R. , Nur Mohammad M. , Bignall Robert J.
Published: May 2011

In recent years the Internet has become the most popular and useful medium for information interchange due to its wide availability, flexibility, universal standards, and distributed architecture. As an outcome of increased dependency on the Internet and networked systems, intrusions have become a major threat to Internet users. Network intrusions may be categorized into the following major types: • Stealing valuable and sensitive information • Destroying or altering information • Obstructing the availability of information by destroying the service-providing ability of a victim’s server
A New Block Data Hiding Method for the Binary Image
Authors: Chen Jeanne , Chen Tung-Shou , Cheng Meng-Wen
Published: May 2011

Great advancements in Web technology have resulted in increase activities on the Internet. Users from all walks of life — e-commerce traders, professionals and ordinary users — have become very dependent on the Internet for all sorts of data transfers, be it important data transactions or friendly exchanges. Therefore, data security measures on the Internet are very essential and important. Also, steganography plays a very important role for protecting the huge amount of data that pass through the internet daily.
Picture Archiving and Communication System in Health Care
Authors: Tong Carrison K.S. , Wong Eric T.T.
Published: May 2011

Radiology is the branch of medicine that deals with the diagnostic and therapeutic applications of radiation. It is often used in X-rays in the diagnosis and treatment of a disease. Filmless radiology is a method of digitizing traditional films into electronic files that can be viewed and saved on a computer. This technology generates clearer and easier-to-read images, allowing the patient the chance of a faster evaluation and diagnosis. The time saved may prove to be a crucial element in the patient’s treatment process. With filmless radiology, images taken from various medical sources can be manipulated to enhance resolution, increasing the clarity of the image. Images can also be transferred internally within departments and externally to other locations such as the office of the patient’s doctor. This is made possible through the picture-archiving and communication system (PACS; Dreyer, Mehta, & Thrall, 2001), which electrsonically captures, transmits, displays, and saves images into digital archives for use at any given time. The PACS functions as a state-of-the-art repository for long-term archiving of digital images, and includes the backup and bandwidth to safeguard uninterrupted network availability. The objective of the picture-archiving and scommunications system is to improve the speed and quality of clinical care by streamlining radiological service and consultation. With instant access to images from virtually anywhere, hospital doctors and clinicians can improve their work processes and speed up the delivery of patient care. Besides making film a thing of the past, the likely benefits would include reduced waiting times for images and reports, and the augmented ability of clinicians since they can get patient information and act upon it much more quickly. The creation of a permanent, nondegradable archive will eliminate the loss of film and so forth. Today, the growing importance of PACS on the fight against highly infectious disease is also identified.
Plastic Optical Fiber Applications
Authors: Louvros Spiros , Iossifides Athanassios C. , Karaboulas Dimitrios , Kotsopoulos Stavros A.
Published: May 2011

Nowadays cabling based on symmetrical copper cables is dominant in almost all telecom applications; glass fibers predominate in long-distance networks. Whereas just a few years ago l0-Mbit/s Ethernet (l0BaseT) had the main share of interfaces in star or tree structures, today’s pure star networks are predominantly set up on the basis of 100-Mbit/s connections.
Privilege Management Infrastructure
Authors: Mundy Darren P. , Otenko Oleksandr
Published: May 2011

Public Key Infrastructures (PKI) are now in place in a number of organizations, and there is a wide amount of material available that can be used to obtain familiarisation with the concept (Adams & Lloyd, 2002; Housley & Polk, 2001; Nash, Brink, & Duane, 2001). Although related to PKI, Privilege Management Infrastructure (PMI) is a recent development in the network security field. PMI has been designed to supply the authorization function lacking in the PKI model. This article will provide an overview of PMI, state the relationship between PKI and PMI, and will finally provide a number of examples of present PMI architectures such as PERMIS (Chadwick & Otenko, 2002), OASIS Active Security (Yao, Moody, & Bacon, 2001) and AKENTI (Thompson, Essari, & Mudumbai, 2003).
Public Opinion and the Internet
Authors: Murphy Peter
Published: May 2011

The development of the “World Wide Web” has had a significant impact on the formation of public opinion in democratic societies. This impact, though, has not been exactly that predicted by early 1990s prophets of the Web, who expected a decentralization of traditional mass media. If anything, the easy accessibility of the Web-enabled Internet (hereafter “the Net”) has extended the audience reach of traditional network media. Despite this, the Net is fundamentally changing the nature of public opinion.
Understanding the Out-of-the-Box Experience
Authors: Gilbert A. Lee
Published: May 2011

Appliances, ideally, are simple to use. You select one you think will meet your needs, get it home, take it out of the box, plug it in, and begin use. For a wireless home network, it may be necessary to read a manual, run a setup wizard, and make a few adjustments to get the performance you want, after which the new device delivers the performance its makers promised, every day, without fail. This scenario describes the expectations most people have from their first experience with networked mobile digital devices (NMD) such as laptop computers, home networks, personal digital assistants, and data-enabled cellphones. In many cases, their actual experiences are often far less satisfactory.
Virtual Reality and HyperReality Technologies in Universities
Authors: Rajasingham Lalita , Tiffin John
Published: May 2011

The term HyperReality (HR) was coined by Nobuyoshi Terashima to refer to “the technological capability to intermix virtual reality (VR) with physical reality (PR) and artificial intelligence (AI) with human intelligence (HI)” (Terashima, 2001, p. 4). HR is a technological capability like nanotechnology, human cloning and artificial intelligence. Like them, it does not as yet exist in the sense of being clearly demonstrable and publicly available. Like them, it is maturing in laboratories where the question ‘if?’ has been replaced by the question ‘when?’ And like them, the implications of its appearance as a basic infrastructure technology are profound and merit careful consideration (Tiffin & Terashima, 2001). Because of this, universities – if they are to be universities – will be involved with HR as a medium and subject of instruction and research, and for the storage and development of knowledge (Tiffin & Rajasingham, 2003). The concepts of HyperUniversities, HyperClasses, Hyperschools and HyperLectures are at the same level of development as the concepts of virtual universities, virtual classes, virtual colleges and virtual schools in the later part of the 1980s (Tiffin & Rajasingham, 1995).
Wireless Emergency Services
Authors: Sun Jun
Published: May 2011

Generally speaking, wireless emergency services can refer to any services that provide immediate help to mobile phone users under emergency conditions. The first widely used WES (wireless emergency services) application is the Wireless Emergency Call Service, which extends the traditional Emergency Call Service (ECS) from fixed-line telephone networks to wireless telephone networks. In the middle of the 1990s, the U.S. Federal Communications Commission (FCC; 1996) issued the order FCC 94-102, requiring wireless carriers to provide the Enhanced 911 Service, the first WECS that delivers emergency calls made from mobile phones as well as caller location information to public-safety answer points (PSAPs). Other countries and regions have planned or implemented similar WECS. For example, the Coordination Group on Access to Location Information by Emergency Services (2002) planned the implementation of E112 service in the European Union.
Attention Aware Systems
Authors: Roda Claudia , Thomas Julie
Published: May 2011

Much information science research has focused on the design of systems enabling users to access, communicate, and use information quickly and efficiently. However the users’ ability to exploit this information is seriously limited by finite human cognitive resources. In cognitive psychology, the role of attentional processes in allocating cognitive resources has been demonstrated to be crucial. Attention is often defined as the set of processes guiding the selection of the environmental stimuli to be attended. Access to information therefore is not only regulated by its availability but also by the users’ choice to attend the information—this choice being governed by attentional processes. Recently several researchers and practitioners in Human Computer Interaction (HCI) have concentrated on the design of systems capable of adapting to, and supporting, human attentional processes. These systems, that often rely on very different technologies and theories, and that are designed for a range of applications, are called attention-aware systems (AAS). In the literature, these systems have also been referred to as Attentive User Interfaces (Vertegaal, 2003). However, we prefer using the former name as it stresses the fact that issues related to attention are relevant to the design of the system as a whole rather than limited to the interface. The recent interest in this field is testified by the publication of special issues in academic journals (e.g., Communication of the ACM, 46(3), 2003; International Journal of Human-Computer Studies, 58(5), 2003) and by the organisation of specialised fora of discussion (e.g., the workshop on “Designing for Attention”; Roda & Thomas, 2004). In this article, we discuss the rationale for AASs and their role within current HCI research, we briefly review current research in AASs, and we highlight some open questions for their design.
Automatic Evaluation of Interfaces on the Internet
Authors: Mandl Thomas
Published: May 2011

Empirical methods in human-computer interaction (HCI) are very expensive, and the large number of information systems on the Internet requires great efforts for their evaluation. Automatic methods try to evaluate the quality of Web pages without human intervention in order to reduce the cost for evaluation. However, automatic evaluation of an interface cannot replace usability testing and other elaborated methods. Many definitions for the quality of information products are discussed in the literature. The user interface and the content are inseparable on the Web, and as a consequence, their evaluation cannot always be separated easily. Thus, content and interface are usually considered as two aspects of quality and are assessed together. A helpful quality definition in this context is provided by Huang, Lee, and Wang (1999). It is shown in Table 1.
Cultural Diversity and Aspects of Human Machine Systems in Mainland China
Authors: Röse Kerstin
Published: May 2011

Addressing intercultural considerations is increasingly important in the product development processes of globally active companies. Culture has a strong relevance for design, which means that culture influences the daily usage of products via design. During humans’ “growing up” time and socialization, the daily usage and the interaction with different products are very important. This forms the user behavior because it supports the forming of users’ basic interaction styles. Education and interaction styles vary in different cultures. Hence, it should be interesting to look at the relation of users’ behavior and culture.
The Development of the Personal Digital Assistant (PDA) Interface
Authors: Garrett Bernard Mark
Published: May 2011

The original idea of a portable computer has been credited to Alan Kay of the Xerox Palo Alto Research Center, who suggested this idea in the 1970s (Kay, 1972a, 1972b; Kay & Goldberg, 1977). He envisioned a notebook-sized, portable computer named the Dynabook that could be used for all of the user’s information needs and used wireless network capabilities for connectivity.
The Effect of Usability Guidelines on Web Site User Emotions
Authors: Chalmers Patricia A.
Published: May 2011

Two decades ago, the U.S. Air Force asked human factors experts to compile a set of guidelines for command and control software because of software usability problems. Many other government agencies and businesses followed. Now hundreds of guidelines exist. Despite all the guidelines, however, most Web sites still do not use them. One of the biggest resulting usability problems is that users cannot find the information they need. In 2001, Sanjay Koyani and James Mathews (2001), researchers for medical Web information, found, “Recent statistics show that over 60% of Web users can’t find the information they’re looking for, even though they’re viewing a site where the information exists”. In 2003, Jakob Nielsen (2003), an internationally known usability expert, reported, “On average across many test tasks, users fail 35% of the time when using Web sites.” Now in 2005, Muneo Kitajima, senior researcher with the National Institute of Advanced Industrial Science and Technology, speaks of the difficulties still present in locating desired information, necessitating tremendous amounts of time attempting to access data (Kitajima, Kariya, Takagi, & Zhang, to appear). This comes at great costs to academia, government, and business, due to erroneous data, lost sales, and decreased credibility of the site in the opinion of users. Since emotions play a great role in lost sales and lost credibility, the goal of this study was to explore the question, “Does the use of usability guidelines affect Web site user emotions?” The experimenter tasked participants to find information on one of two sites. The information existed on both sites; however, one site scored low on usability, and one scored high. After finding nine pieces of information, participants reported their frequency of excitement, satisfaction, fatigue, boredom, confusion, disorientation, anxiety, and frustration. Results favored the site scoring high on usability.