Zahir Tari

Bio: Zahir Tari is an academic researcher from RMIT University. The author has contributed to research in topics: Cloud computing & Web service. The author has an hindex of 40, co-authored 346 publications receiving 7875 citations. Previous affiliations of Zahir Tari include Melbourne Institute of Technology & Queensland University of Technology.

A Survey of Clustering Algorithms for Big Data: Taxonomy and Empirical Analysis

Abstract: Clustering algorithms have emerged as an alternative powerful meta-learning tool to accurately analyze the massive volume of data generated by modern applications. In particular, their main goal is to categorize data into clusters such that objects are grouped in the same cluster when they are similar according to specific metrics. There is a vast body of knowledge in the area of clustering and there has been attempts to analyze and categorize them for a larger number of applications. However, one of the major issues in using clustering algorithms for big data that causes confusion amongst practitioners is the lack of consensus in the definition of their properties as well as a lack of formal categorization. With the intention of alleviating these problems, this paper introduces concepts and algorithms related to clustering, a concise survey of existing (clustering) algorithms as well as providing a comparison, both from a theoretical and an empirical perspective. From a theoretical perspective, we developed a categorizing framework based on the main properties pointed out in previous studies. Empirically, we conducted extensive experiments where we compared the most representative algorithm from each of the categories using a large number of real (big) data sets. The effectiveness of the candidate clustering algorithms is measured through a number of internal and external validity metrics, stability, runtime, and scalability tests. In addition, we highlighted the set of clustering algorithms that are the best performing for big data.

Security and Privacy in Cloud Computing

Abstract: Significant research and development efforts in both industry and academia aim to improve the cloud's security and privacy The author discusses related challenges, opportunities, and solutions

On the Move to Meaningful Internet Systems 2002: CoopIS, DOA, and ODBASE

Abstract: COOPIS 2002 FULL PAPERS.- Developing Evolutionary Cost Models for Query Optimization in a Dynamic Multidatabase Environment.- A Conceptual Markup Language That Supports Interoperability between Business Rule Modeling Systems.- Distributed Description Logics: Directed Domain Correspondences in Federated Information Sources.- Synchronization of Concurrent Workflows Using Interaction Expressions and Coordination Protocols.- CPM Revisited - An Architecture Comparison.- Modeling Coordination and Control in Cross-Organizational Workflows.- View Propagation and Inconsistency Detection for Cooperative Mobile Agents.- On Real-Time Top k Querying for Mobile Services.- Mobile Agents in Mobile Data Access Systems.- Using Agent Control and Communication in a Distributed Workflow Information System.- An Extended Alternating-Offers Bargaining Protocol for Automated Negotiation in Multi-agent Systems.- A Human Based Perception Model for Cooperative Intelligent Virtual Agents.- A Decentralized Algorithm for Coordinating Independent Peers: An Initial Examination.- Supporting Peer-to-Peer User Communities.- Context Spaces - Self-Structuring Distributed Networks for Contextual Messaging and Resource Discovery.- Supporting Cooperative Learning in Distributed Project Teams.- Discovering Emergent Virtual Work Processes in Collaborative Systems.- Flexible Merging for Asynchronous Collaborative Systems.- A Multi-version Transaction Model to Improve Data Availability in Mobile Computing.- Finding Trading Partners to Establish Ad-hoc Business Processes.- Regulating Work in Digital Enterprises: A Flexible Managerial Framework.- Collecting and Querying Distributed Traces of Composite Service Executions.- An Architecture of a Web-Based Collaborative Image Search Engine.- Parallel Processing with Autonomous Databases in a Cluster System.- Querying XML Sources Using an Ontology-Based Mediator.- Handling Partial Matches in Semistructured Data with Cooperative Query Answering Techniques.- Efficient Querying of Distributed Resources in Mediator Systems.- Managing Data Quality in Cooperative Information Systems.- Adaptive Fault Tolerant Hospital Resource Scheduling.- COOPIS 2002 POSTERS.- Mining 'Living' Data - Providing Context Information to a Negotiation Process.- The Neem Platform: An Evolvable Framework for Perceptual Collaborative Applications.- A Model for Process Service Interaction.- Leveraging Dynamic Inheritance in Complex Ontology Representation.- A Database Approach to Global Document Spaces: Replacing Files with Shared, Connected Objects.- PROLOG/RDBMS Integration in the NED Intelligent Information System.- New Location Management for Reducing HLR Overhead Traffic in Mobile Networks.- DOA 2002 FULL PAPERS.- A Filter Object Framework for MICO.- Design and Performance of a Modular Portable Object Adapter for Distributed, Real-Time, and Embedded CORBA Applications.- Design and Performance of Asynchronous Method Handling for CORBA.- Web Services Interoperability: A Practitioner's Experience.- Cooking the Web-ERP.- Web Services and CORBA.- Composing and Deploying Grid Middleware Web Services Using Model Driven Architecture.- A Design Pattern for Efficient Retrieval of Large Data Sets from Remote Data Sources.- Replacement Policies for a Distributed Object Caching Service.- Design and Performance of a Media Gateway Trader.- Object Security Attributes: Enabling Application-Specific Access Control in Middleware.- Integrating Optimistic Virtual Synchrony to a CORBA Object Group Service.- Implementing a CORBA-Based Architecture for Leveraging the Security Level of Existing Applications.- Reconciling Replication and Transactions for the End-to-End Reliability of CORBA Applications.- Runtime Performance Modeling and Measurement of Adaptive Distributed Object Applications.- An Infrastructure for Adaptable Middleware.- A Reflective Middleware Framework for Communication in Dynamic Environments.- A Dynamic Proxy Based Architecture to Support Distributed Java Objects in a Mobile Environment.- A CORBA-Based Work .ow Management System for Wireless Communication Environments.- Customizable Deployment, Composition, and Hosting of Distributed Java Applications.- Resource Discovery for Pervasive Environments.- An Adaptive Scheduling Service for Real-Time CORBA.- The Design and Performance of the jRate Real-Time Java Implementation.- Empirical Differences between COTS Middleware Scheduling Strategies.- Adding Business Rules and Constraints in Component Based Applications.- Configuring the Communication Middleware to Support Multi-user Object-Oriented Environments.- Distributed Component System Based on Architecture Description: The SOFA Experience.- On Components with Explicit Protocols Satisfying a Notion of Correctness by Construction.- ODBASE 2002 FULL PAPERS.- Well-Founded Optimism: Inheritance in Frame-Based Knowledge Bases.- A Defeasible Ontology Language.- On the Semantics of Anonymous Identity and Reification.- Extending Datatype Support in Web Ontology Reasoning.- A Conceptual Modeling Approach for Semantics-Driven Enterprise Applications.- Towards Ontological Foundations for UML Conceptual Models.- Towards Secure Object Oriented Database Systems.- Information-Flow-Based Ontology Mapping.- The Semantics of Semantic Annotation.- A User Behavior-Based Agent for Improving Web Usage.- Usage-Oriented Evolution of Ontology-Based Knowledge Management Systems.- OntoEdit: Guiding Ontology Development by Methodology and Inferencing.- Open Mind Common Sense: Knowledge Acquisition from the General Public.- Formal Ontology Engineering in the DOGMA Approach.- A Dynamic Model for Mapping XML Elements in a Object-Oriented Fashion.- KF-Diff+: Highly Efficient Change Detection Algorithm for XML Documents.- Naming in XML Documents.- Reasoning with Ontologies by Using Knowledge Conjunction in Conceptual Graphs.- Natural Language Annotations for the Semantic Web.- A Metadata Integration Assistant Generator for Heterogeneous Distributed Databases.- Intelligent Web Search via Personalizable Meta-search Agents.- ODBASE 2002 Posters.- Defining Information System Components.- Discovering Resources in the Semantic Web.- Geodata Interoperation via Semantic Correspondences.- Extending Datatype Support inWeb Ontology Reasoning.

The Self-Organizing Map

Abstract: An overview of the self-organizing map algorithm, on which the papers in this issue are based, is presented in this article.