Joseph G. Davis

• PhD
• Professor Emeritus at The University of Sydney

Unlocking the full potential of Knowledge Graphs (KGs) to enable or enhance various semantic and other applications requires Data Management Systems (DMSs) to efficiently store and process the content of KGs. However, the increases in the size and variety of KG datasets as well as the growing diversity of KG queries pose efficiency challenges for t...

We propose a novel approach to designing RDF-stores with the goal of improving the consistency and predictability of query performance. When designing these systems, three properties are commonly desired: support for the full range of SPARQL query features (Q), support for widely varying RDF datasets in terms of structuredness and size (S), and hig...

Recent advances in the large-scale adoption of information and communication technologies in manufacturing processes, known as Industry 4.0 or Smart Manufacturing, provide us a window into how the manufacturing sector will evolve in the coming decades. As a result of these initiatives, manufacturing firms have started to integrate a series of emerg...

Digital Twin is an emerging technology at the forefront of Industry 4.0, with the ultimate goal of combining the physical space and the virtual space. To date, the Digital Twin concept has been applied in many engineering fields, providing useful insights in the areas of engineering design, manufacturing, automation, and construction industry. Whil...

Digital Twin is an emerging technology at the forefront of Industry 4.0, with the ultimate goal of combining the physical space and the virtual space. To date, the Digital Twin concept has been applied in many engineering fields, providing useful insights in the areas of engineering design, manufacturing, automation, and construction industry. Whil...

Knowledge Graphs (KGs) have emerged as the de-facto standard for modeling and querying datasets with a graph-like structure in the Semantic Web domain. Our focus is on the performance challenges associated with querying KGs. We developed three informationally equivalent JSON-based representations for KGs, namely, Subject-based Name/Value (JSON-SNV)...

As Knowledge Graphs (KGs) continue to gain widespread momentum for use in different domains, storing the relevant KG content and efficiently executing queries over them are becoming increasingly important. A range of Data Management Systems (DMSs) have been employed to process KGs. This paper aims to provide an in-depth analysis of query performanc...

There is growing interest in the use of Knowledge Graphs (KGs) for the representation, exchange, and reuse of scientific data. While KGs offer the prospect of improving the infrastructure for working with scalable and reusable scholarly data consistent with the FAIR (Findability, Accessibility, Interoperability, and Reusability) principles, the sta...

While recent research has highlighted the importance of identifying diverse aspects of user preferences in terms of the quality of recommendations, most of the widely used performance measures tend to consider the accuracy of the recommendations and ignore other important aspects such as preference for diversity in recommendations. This is despite...

For network analysts, understanding how traffic flows through a network is crucial to network management and forensics such as network monitoring, vulnerability assessment and defence. In order to understand how traffic flows through a network, network analysts typically access multiple, disparate data sources and mentally fuse this information. Pr...

Emerging developments in service-based systems have contributed to a range of proposals for the rapid development of complex applications by composing existing web services through standards-based interfaces. With the availability of a large number of such services offering identical functionality at varying levels of price and other Quality-of-Ser...

Understanding our past can determine our ability to understand the present. Many people associate cultural heritage with the ancient past and history; however, cultural heritage should be seen as a continuous tradition that lives through daily practices. In this paper, we present the details of our research dealing with one aspect of Balinese cultu...

The open source development model has become a paradigm shift from traditional in-house/closed-source software development model, with many successes. Traditionally, open source projects were characterized essentially by their individual volunteer developers. Such tradition has changed significantly with the participation of many organizations in p...

Composite service selection refers to the process of selecting an optimal set of web services out of a pool of available candidates based on their quality of service and price. The goal is to logically compose these atomic web services and create value-added composite services which in turn can be used to develop service-based systems. Existing app...

The project aims to design and build a digital portal which will document, organise, and preserve aspects of Balinese cultural heritage and related knowledge for the benefit of the wider community and the younger generations in particular. We present the details of our research dealing with one aspect of Balinese culture, the Balinese traditional c...

One of the goals of digital preservation of cultural heritage is to gather, refine, maintain, and share cultural resources that can subsequently be used and developed by scholars, members of the community, and future generations. We present the details of our research dealing with one aspect of Balinese culture, the Balinese traditional communicati...

Linked Data allows structured data to be published in a standard manner so that datasets from diverse domains can be interlinked. By leveraging Semantic Web standards and technologies, a growing amount of semantic content has been published on the Web as Linked Open Data (LOD). The LOD cloud has made available a large volume of structured data in a...

The DBpedia-MovieLens Evaluation Datasets are provided by linking items (movies) in the MovieLens 100K and 1M datasets (http://grouplens.org/datasets/movielens/) to their corresponding DBpedia resources. Further (automatic and manual) post-processing was done to clean and perfect the mappings. The mapping between resources in DBpedia and other Link...

This paper presents an evaluation of the smartphone platforms based on security policies provided by platform owners to determine which of the platforms is secure, safe and reliable. The issue of secrecy and confidentiality is very vital when dealing with users. Security of a particular platform is of essence to the smartphone industry and users, a...

This paper performs an evaluation of the various smartphone platforms based on performance using simulation programs. Different experiments to test the platforms for their performance were conducted by means of some designed applications and the results registered and analyzed. The various applications were used to process string, integers, floatin...

Service level agreements (SLAs) for complex IT-intensive business-to-business (CITI-B2B) services are high-level representations of services to be enacted, with predominantly quantifiable performance targets. Inevitably, there is a gap between this representation and the nuanced practices of enactment adapting to emergent conditions over time. Over...

The Linked Open Data (LOD) project is a community effort that aims to publish structured data using open and liberal licences. The LOD cloud provides free access to datasets in diverse areas such as media, geography, publications and life sciences. These datasets are publicly available for machine and human consumption using Semantic Web standards...

Harnessing human computation through crowdsourcing offers an alternative approach to solving complex problems, especially those that are relatively easy for humans but difficult for computers. Micro-tasking platforms such as Amazon Mechanical Turk have attracted large, on-demand work force of millions of workers as well as hundreds of thousands of...

Web service composition (WSC) offers a range of solutions for rapid creation of complex applications in advanced service-oriented systems by facilitating the composition of already existing concrete web services. One critical challenge in WSC is the dynamic selection of concrete services to be bound to the abstract composite service. In this paper,...

This book constitutes the thoroughly refereed proceedings of the Third Australian Symposium on Service Research and Innovation, ASSRI 2013, held in Sydney, NSW, Australia, in November 2013. Overall, eight research papers were carefully reviewed and selected from 18 submissions. They are multidisciplinary in scope and cover strategic, organizational...

We propose a novel market-based approach for dynamic composite service selection based on combinatorial auctions. The combinatorial auction model that we developed allows us to incorporate service providers' and requesters' preferences in the service selection process. From the providers' perspective, the combinatorial formulation allows them to ex...

Ranking of universities represents a complex endeavor which involves gathering, weighting, and analyzing diverse data. Emerging semantic technologies enable the Web of Data, a giant graph of interconnected information resources, also known as Linked Data. A recent community effort, Linking Open Data project, offers the possibility of accessing a la...

By leveraging Semantic Web technologies, Linked Open Data provides an extensive amount of structured information in a wide variety of domains. Principles of Linked Data facilitate access and re-use of semantic information, both for human and machine consumption. However, information overload due to the availability of a large amount of semantic dat...

Harnessing human computation through crowdsourcing offers a new approach to solving complex problems, especially those that are relatively easy for humans but difficult for computers. Micro-tasking platforms such as Amazon Mechanical Turk have attracted large, on-demand workforces of millions of workers as well as hundreds of thousands of job reque...

Linked Data offers new opportunities for Semantic Web-based application development by connecting structured information from various domains. These technologies allow machines and software agents to automatically interpret and consume Linked Data and provide users with intelligent query answering services. In order to enable advanced and innovativ...

As Cloud Computing adoption by enterprise customers grows, so too the need for optimal utilisation of their virtual resources. Likewise, cost pressures on cloud providers with a utility business model e.g. Amazon Web Services, would also need to optimise the utilisation of their physical infrastructure. Clearly, the ability to predict demand would...

In this demonstration we present OntoAssist, a semantic navigation support system designed to address the ontology evolution problem and thus improve the quality of ontology-based search. OntoAssist integrates the computational features of an existing search engine with the human computation provided by the crowd of users to find useful search resu...

Research in requirements engineering (RE) has been growing in the last few years. RE researchers are generally concerned with a set of open issues such as: (i) the need for a well-defined process to identify and specify the requirements scope, (ii) suitable mechanisms to support communication among different stakeholders and development teams invol...

The evolving vision of Web 3.0 is based on the balanced integration of diverse services provided by human agents and machines over the World Wide Web. This is also the intuition that drives crowdservicing, which helps in creating platforms on which new applications and even enterprises can be build. Crowdsourcing as a concept as well as a practice...

Service systems rely on internal interactions of service provider agents and the external interactions with customers in the design and delivery of services. Careful analysis and modeling of such interactions are essential to the design of effective service systems. This paper focuses on service interaction networks in the context of the design and...

We investigate three aspects of collaborative learning in uncertain environments - aversion to exploration, structure of the collaborative network, and strategic policy. In uncertain environments, these three aspects are likely to operate simultaneously whereas previous research at best has focussed on two, if not one, of these aspects. This paper...

The World Wide Web (WWW) has undergone significant evolution in the past decade. The emergq web 3.0 is characterized by the vision of achieving a balanced integration of services provided by machmes and human agents. Ths is also the logic of 'crowdservicing' which has led to the creation of platforms on whch new applicatiom and even enterprises can...

The main problem of tag-based search in collaborative tagging system (CTS) is the lack of explicit semantic relations between tags. To address this problem, we propose an approach based on the integration of symmetrical and asymmetrical similarity measures to calibrate the relatedness between tags and then further organize them into an ontological...

With the growing presence of BPM and SOA in the IT industry, their impact on the IT education will be profound. Many institutions are becoming aware of the acute need of developing learning and teaching resource frameworks for the BPM and SOA. In this paper, we present part of such an effort from a team at the University of New South Wales, current...

This paper investigates the unification of folksonomies and ontologies in such a way that the resulting structures can better support exploration and search on the World Wide Web. First, an integrated computational method is employed to extract the ontological structures from folksonomies. It exploits the power of low support association rule minin...

Service level agreements (SLAs) constitute some of the most important instruments for representing and managing IT-centric services performance and value. However, achieving realistic and effective SLAs can be elusive. The problem is relatively under-researched and normative descriptions of what should be represented, monitored and measured in SLAs...

This paper develops a service for ontology evolution based on crowdsourcing. The approach is demonstrated using OntoAssist, a specially designed semantic search service that is capable of capturing and disambiguating user's search intent as well as automatically enabling ontology evolution. Successful and consistent ontology evolution often require...

In this paper, a novel fuzzy classifier for multi-classification problems, based on support vector data description (SVDD) and improved PCM, is proposed. The proposed method is the robust version of SVDD by assigning a weight to each data point, which ...

Collaborative tagging systems have recently emerged as one of the rapidly growing web 2.0 applications. The informal social classification struc- ture in these systems, also known as folksonomy, provides a convenient way to annotate resources by allowing users to use any keyword or tag that they find relevant. In turn, the flat and non-hierarchical...

The role of data mining is to search "the space of candidate hypotheses" to offer solutions, whereas the role of statistics is to validate the hypotheses offered by the data-mining process. In this paper we propose Association Rules Networks (ARNs) as a structure for synthesizing, pruning, and analyzing a collection of association rules to construc...

In this paper we use a large firm-level dataset to extend previous studies by augmenting the endogenous growth accounting framework with a data mining technique to analyze the complex relationships between the use of IT and organizational practices. There is emerging evidence of recent emphasis on organizational factors and a greater shift towards...

A model of a knowledge intensive service system is introduced to study knowledge sharing in these systems. Simulation experiments based on the model are conducted to relate particular aspects of knowledge creation and sharing to a metric of service performance. The results indicate that certain network configurations of knowledge sharing among the...

The negative consequences of information overload are well understood across a range of disciplines even though the causative factors that contribute to it have not been coherently researched. We apply the concept of 'aversion to loss' from prospect theory and explore its effects in the context of information processing for decision making. A contr...

Ontological approach is one of those promising solutions to improve search precision, resource navigation and retrieval by providing shared vocabularies and semantic relations for translating and integrating the different sources. But the progress has slowed down due to the knowledge acquisition bottleneck. In this paper, we present an integrated c...

We present a model to describe open source software (OSS) bug dynamics. We validated the model using real world data and performed simulation experiments. The results show that the model has the ability to predict bug occurrences and failure rates. The results also reveal that there exists an optimal release cycle for effectively managing OSS quali...

We analyzed the major differences between closed and open source software development from a software reliability perspective. We examined real world bug report data from six open source software projects, as well as the relationship between the release cycles and the stability characteristics of the bug report data of open source software projects...

The extant research investigating the relationship between knowledge management (KM) strategies and organizational performance has yielded inconclusive results. Our paper revisits this research problem by drawing on complementarity theory from Economics. The empirical segment of our work is based on data on KM strategies and organizational performa...

Studies in Information Systems (IS) research have widely documented task-oriented and communication structure effects as a result of information and communication technology (ICT) use. These effects have been evidenced at inter- and intra-organisational and occupational community levels. Research on the direct interplay between social network struc...

Currently, most web search engines perform search on nearly a whole copy of the web corpus. There are also tools to add search functionality to a single site. Nonetheless, there is little research into search related to online communities: set of related websites or weblogs. To fill this gap, a peer-to-peer search engine is presented in this paper....

With the emergence of a range of second generation Internet based services such as Weblogs and their hosting services, many loosely organized communities of bloggers have started to form around common interests. Those communities have quickly evolved into a new information and knowledge dissemination channel. Most current search engines cannot disc...

Recent research on firm level productivity and organizational performance has highlighted the importance of complementarity among organizational practices. A number of studies have developed methods to test the existence of complementarity among such organizational variables. However, despite these advances in the study of industrial organization a...

Email networks in contemporary organizations are fairly representative of the underlying communications networks. We show that changes in communication networks have implications for studying organization disintegration. In this paper, we analyzed the changing communication network structure at Enron Corporation during the period of its disintegrat...

Despite growing evidence of a positive impact of Information Technology (IT) investments on firm performance, the variations in the results across organisations are still significant. This research takes a fresh approach by addressing complementarity impacts of organisational practices on three different dimensions of IT business value (ITBV). The...

Weblog has quickly evolved into a new information and knowledge dissemination channel. Yet it is not easy to discover weblog communities through keyword search. The main contribution of this paper is the study of weblog communities from the perspective of social network analysis. We proposed a new way of collecting and preparing data for weblog com...

Ontologies have been created for many different subjects and by independent groups around the world. The nonexistence of a commonly accepted and used general purpose upper-ontology makes it difficult to integrate these ontologies through merge and alignment operations. The majority of the algorithms proposed so far rely on syntactic analysis, disre...

In this paper, we report a two level study on weblog link structures. At the micro level, we carried out an in-depth investigation of individual weblogs. Our goal was to obtain some preliminary understanding of the different types of links that might indicate underlying communities of bloggers. Complete and detailed link data was collected from eig...

The impacts of the evolving information technology (IT) on organisations, markets, industries, and economies have been researched intensively. Aspects studied have included productivity, employment, business value, markets, organisation, and industry structure, to name a few. With the increasing availability of panel data spanning longer periods, i...

Ontologies have been created for many different subjects and by independent groups wound the world. The nonexistence of a commonly accepted and used general purpose upper-ontology makes it difficult to integrate these ontologies through merge and alignment operations. The majority of the algorithms proposed so far rely on syntactic analysis, disreg...

We collected bug tracking data from a few popular open source projects and investigated the time related bug reporting patterns from them. The results indicate that along its development cycle, open source projects exhibit similar reliability growth pattern with that of closed source project. Bug arrivals of most open source project will stabilize...

Purpose This paper aims to unravel the complexities associated with knowledge sharing in large global organizations through a field study carried out in a large, multinational company (Du Pont), focusing on the critical issues, concrete practices, bottle‐necks, and constraints in knowledge sharing. The tension between “local” production of much of...

In this paper, we introduce social network analysis for investigating the effect of network position and Information and Communication Technology (ICT) use on the performance of general practitioners (GPs) residing in rural Australia. Here, we highlight the data collection procedure, its benefits and limitations and standard measures of social netw...

Knowledge representation has always been a major concern when designing systems for technology transfer because of its impact on the system's usability. The Embrapa's Information Agency was designed as a space for exchanging knowledge among farmers, agricultural researchers and rural extension technicians. In its first version, the system represent...

We collected bug tracking data from a few popular open source projects and investigated the time related bug reporting patterns from them. The results indicate that along its development cycle, open source projects exhibit similar reliability growth pattern with that of closed source project. Bug arrivals of most open source project will stabilize...

This paper traces the origins of Knowledge Management as an academic area of inquiry and as a key managerial concern in contemporary organizations. This is based on an overview of related developments in a number of fields including Economics, Organisational Studies, and Information Systems as well as some of the important developments in the busin...

An innate characteristic of the development of ontologies is that they are often created by independent groups of expertise, which generates the necessity of merging and aligning ontologies covering overlapping domains. However, a central issue in the merging process is the evaluation of the differences between two ontologies, viz. the establishmen...

Ontologies have been developed for a number of knowledge domains as diverse as clinical terminology, photo camera parts and micro-array gene expression data. However, processing user queries over a set of overlapping ontologies is not straightforward because they have often been created by independent groups of expertise, each of them adopting diff...

Web services and service oriented architecture (SOA) represent a radical departure from traditional monolithic, tightly bound, customized applications with proprietary interfaces. Their range however is limited as yet by the very structure and standardization which support their interoperability. While they are able to support heterogeneity of tech...

Here we propose an adaptive local pruning method for association rules. Our method exploits the exact mapping between a certain class of association rules, namely those whose consequents are singletons and backward directed hypergraphs (B-graphs). The hypergraph which represents the association rules is called an association rules network(ARN). Her...

The complex relationships between information technology investments and business value have been the focus of intensive research in recent years. There appears to be a discernible trend toward a more nuanced view in which the differential effects of the various categories of IT capital such as hardware, software, and their interactions with organi...

This paper presents a case study in which discourse analysis was used to suggest process improvements in two knowledge management services (KMS). It employs linguistic analysis as the means for assessing the degree to which each KMS is aligned to the users' needs. Areas requiring improvement are identified linguistically based on the differences be...

The Open Source Software(OSS) movement has attracted considerable attention in the last few years. In this paper we report our results of mining data acquired from SourceForge.net, the largest open source software hosting website. In the process we introduce Association Rules Network(ARN), a (hyper)graphical model to represent a special class of as...

This paper updates the research progress in investigating the relationships between information technology (IT) investments and productivity in Australia. Based on the production function approach, two empirical tests using two different Australian datasets were performed. The first test focuses on productivity attributable to IT capital equipment...

This paper describes the development and testing of a system that provides casual and novice users with simple yet powerful tools to manipulate statistical data from external sources. The prototype combines Multi-Dimensional Databases and Online Analytical Processing tools to produce a generic Web-based interface compatible with a wide variety of t...

This paper focuses on the problem of information overload for newcomers in an organisation. We propose to address it by constructing a smart personal training assistant based upon workflow tools to drive temporal management of a just-in- time workplace training system which will deliver a personalised and structured presentation of organisational d...

Abstract The provision of computer support for collaborative work is a central concern for Information Systems (IS) research and practice. In this paper we present the details of an information flow study undertaken in the household division of a large European design and manufacturing company,(Delta) with the goal of eliciting and refining the use...

A complex decision problem dealing with crude-oil trading is hierarchically decomposed into multiple subproblems. A blackboard architecture for a Decision Support System (DSS) called SCOPE is developed in which the subproblems generated during the initial decision analysis can be mapped to relevant knowledge sources incorporating the most appropria...