A token-based independent update protocol for managing replicated objects

This paper presents the design and evaluation of a token-based protocol supporting independent updates of replicated objects. The paper makes three major contributions. Firstly, a token is used to simplify the control of update propagation and ordering. Secondly a partial commit state is introduced to support independent updates and to enhance the efficiency of transaction processing. Thirdly, a data partition methodology based on priorities is adopted to reduce update conflicts. We evaluate our protocol in comparison of two existing replication-control protocols in terms of transaction processing efficiency.

How intimate are Australian e-business retail supply chains?

The adoption of electronic commerce strategies is becoming an important means of assisting industries, and indeed whole economies, to gain significant net benefits. The extent to which e-commerce-based strategies, such as quick response and efficient consumer response, might have an effect on local economies depends in part on how readily they are being adopted. The dominant form of adoption of these strategies is to be found in the business-to-business forms of e-commerce. To be successful, business partners must be in a position to develop customer intimacy through sharing of information, to improve their stock replenishment practices, and enhance their levels of online customer support. This paper presents the initial results of a national survey completed in the retail sector of the Australian economy, that assesses how well Australian industry is responding to these e-commerce challenges.

An efficient replicated data management approach for peer-to-peer systems

The availability of critical services and their data can be significantly increased by replicating them on multiple systems connected with each other, even in the face of system and network failures. In some platforms such as peer-to-peer (P2P) systems, their inherent characteristic mandates the employment of some form of replication to provide acceptable service to their users. However, the problem of how best to replicate data to build highly available peer-to-peer systems is still an open problem. In this paper, we propose an approach to address the data replication problem on P2P systems. The proposed scheme is compared with other techniques and is shown to require less communication cost for an operation as well as provide higher degree of data availability.

A solution for fault tolerance in replicated database systems

A distributed database system is subject to site failure and link failure. This paper presents a reactive system approach to achieving fault tolerance in such a system. The reactive system concepts are an attractive paradigm for system design, development and maintenance because it separates policies from mechanisms. In the paper we give a solution using different reactive modules to implement the fault tolerant policies and the failure detection mechanisms. The solution shows that they can be separated without impact on each other; thus the system can adapt to constant changes in environments and user requirements.

Automating the construction of replicated objects in a cluster of workstations

This paper describes a tool that mimics the design of the remote procedure call (RPC) system to support the building of replicated objects in a cluster of workstations (COW). The tool includes an interface definition language for describing a replica group, a language preprocessor and a runtime library system. The paper also presents one example and discusses some performance issues for replicated objects.

An analysis of update ordering in a cluster of replicated servers

This paper analyses update ordering and its impact on the performance of a cluster of replicated servers. We propose a model for update orderings and constraints and develop a number of algorithms for implementing different ordering constraints. A performance study is then carried out to analyse the update ordering model.

A solution for fault-tolerance in replicated database systems

A distributed database system is subject to site failure and link failure. This paper presents a reactive system approach to achieving the fault-tolerance in such a system. The reactive system concepts are an attractive paradigm for system design, development and maintenance because it separates policies from mechanisms. In the paper we give a solution using different reactive modules to implement the fault-tolerant policies and the failure detection mechanisms. The solution shows that they can be separated without impact on each other thus the system can adapt to constant changes in user requirements.

Innovation chains: possibilities and constraints for critical perspectives on computers, difference and educational innovation

While declarations of ‘innovativeness’ are easily found in most educational contexts, it is significantly more difficult to locate detailed definitions of what educational innovation actually means. In this paper we are interested in identifying the extent to which mainstream takes on ‘innovation’ (as played out in contemporary technology and equity debates) reflect or respond to what we will define as the more innovative dimensions of innovation literature itself. Our aim throughout this paper, then, is to begin the complex process of developing a means for distinguishing between projects that are ‘badged’ as innovative and projects that are more demonstrably (and sustainably) innovative. In this process we will distinguish between what Shiv Visvanathn describes as “innovation chains”— dynamic, rhizomatic, transformative responses to the contemporary world that lead to fundamentally new ways of conceptualising technology, culture and difference—and the constraints—or chains—provided by dominant understandings of innovation: chains which anchor us to existing, hegemonic and limiting understandings of student
diversity and educational technology.

An efficient replicated data access approach for large-scale distributed systems

In data-intensive distributed systems, replication is the most widely used approach to offer high data availability, low bandwidth consumption, increased fault-tolerance and improved scalability of the overall system. Replication-based systems implement replica control protocols that enforce a specified semantics of accessing the data. Also, the performance depends on a number of factors, the chief of which is the protocol used to maintain consistency among object replica. In this paper, we propose a new low-cost and high data availability protocol called the box-shaped grid structure for maintaining consistency of replicated data on networked distributed computing systems. We show that the proposed protocol provides high data availability, low communication costs, and increased fault-tolerance as compared to the baseline replica control protocols.

2-(2-Pyridylamino)Pyridinium2-(2-Pyridylamino)pyridinium chloride phosphorous acid: one-dimensional hydrogen-bonded and [π]-[π] stacked supramolecular chains

In the crystal structure of the title compound, C₁₀H₁₀N₃⁺·Cl-^·[P(O)(OH)₂H], the chloride ion and phosphorous acid form a one-dimensional hydrogen-bonded chain, while the 2-(2-pyridylamino)pyridinium cations form a second chain through [π]-[π] stacking. The two parallel chains are connected via a PO...H-N hydrogen bond and a weak pyridinium-to-chloride interaction.

A construct of sequential service quality in service encounter chains

Studies of the construct of service quality have traditionally been undertaken from the perspective of the service receiver. More recently, research has focused on both the service provider's perspective and the service receiver's perspective. In addition, there have also been some triadic network approaches to the study of service quality. However, there has been very little research into sequential service quality in service-encounter chains (that is, consecutive service performances in a series of service encounters). The incorporation of connected service encounters in services management can improve understanding of sequential service quality in service-encounter chains. This paper provides a customized construct of sequential service quality and  highlights the importance of time, context, and performance threshold in service-encounter chains. Furthermore, the paper presents a customized six-dimensional construct of sequential service quality.

The development of a neo-industrial organisation methodology for describing and comparing structural and behavioural characteristics of construction supply chains

The model draws from theories of industrial economics and supply chain literature, and is an attempt to advance the construction supply chain field through the development of an industrial organisational methodology to describe construction supply chains.
Empirical studies have examined the industrial organisation of other industries, typically forming descriptions based upon vertical integration and horizontal market concentration. A review of the trends in the supply chain literature indicate there is a need to develop a model to describe the industrial organisation of the construction industry through supply chain structure. The merging of the supply chain concept with the industrial organisation model as a methodology for understanding the structural characteristics is an important contribution to construction economic theory. The paper begins to develop a language for describing the structure and behaviour of supply chains specific to the construction industry and is so doing suggests a neo-industrial organisation approach.