Description:
The paper starts with an evaluation of a group of ICT organizations in a regional Victorian town and using a range of qualitative and quantitative data evaluates whether there is a cluster emerging and if so what are the processes of clustering that underpin this. Using archival and interview data the paper then examines key events and turning points in the development of what might be identified as a nascent cluster (Rosenfeld, 1997). In the context of current public policy that directly or indirectly supports ‘clustering’, the paper then assesses the effectiveness of public policy versus private action in the development of regional agglomerations of organisations and institutions that may be called clusters.
Description:
The paper starts with an evaluation of a group of ICT organizations in a regional Victorian town and using a range of qualitative and quantitative data evaluates whether there is a cluster emerging and if so what are the processes of clustering that underpin this. Using archival and interview data the paper then examines key events and turning points in the development of what might be identified as a nascent cluster (Rosenfeld, 1997). In the context of current public policy that directly or indirectly supports ‘clustering’, the paper then assesses the effectiveness of public policy versus private action in the development of regional agglomerations of organisations and institutions that may be called clusters.
Description:
Summary Wireless sensor networks (WSNs) consist of resource‐starving miniature sensor nodes deployed in a remote and hostile environment. These networks operate on small batteries for days, months, and even years depending on the requirements of monitored applications. The battery‐powered operation and inaccessible human terrains make it practically infeasible to recharge the nodes unless some energy‐scavenging techniques are used. These networks experience threats at various layers and, as such, are vulnerable to a wide range of attacks. The resource‐constrained nature of sensor nodes, inaccessible human terrains, and error‐prone communication links make it obligatory to design lightweight but robust and secured schemes for these networks. In view of these limitations, we aim to design an extremely lightweight payload‐based mutual authentication scheme for a cluster‐based hierarchical WSN. The proposed scheme, also known as payload‐based mutual authentication for WSNs, operates in 2 steps. First, an optimal percentage of cluster heads is elected, authenticated, and allowed to communicate with neighboring nodes. Second, each cluster head, in a role of server, authenticates the nearby nodes for cluster formation. We validate our proposed scheme using various simulation metrics that outperform the existing schemes.
Description:
This paper discusses wine and tourism clusters and the recent innovation of wine tourism in which businesses operate within both industries. The concept of micro-clusters is examined in terms of trust, networking, collaboration and other activities, all of which are argued to depend on the concepts of game theory and sunk costs. The study involved both interviews and a questionnaire. Conceptual variables are created from the questionnaire responses using factor analysis. The determinants of cluster activities are modelled using regression analysis. The effects of industry, place and respondents' entrepreneurial characteristics are used as exogenous variables. The study finds that industry does seem to be more important than place in the determination of networking and cooperative cluster activities, and that members of the wine tourism industry participate more in these activities than members of the tourism or hospitality industries. The addition of three variables that embody the entrepreneurial characteristics of the respondents approximately doubles the explanatory power of the original models. There is evidence to suggest that cluster activities are idiosyncratic for each industry-place cluster. The effects of firm size on cluster activities are also examined. No evidence is found of cooperative activities depending on cluster size. The main results support the contention that sunk costs are important in the determination of cluster activities.
Description:
This paper discusses wine and tourism clusters and the recent innovation of wine tourism in which businesses operate within both industries. The concept of micro-clusters is examined in terms of trust, networking, collaboration and other activities, all of which are argued to depend on the concepts of game theory and sunk costs. The study involved both interviews and a questionnaire. Conceptual variables are created from the questionnaire responses using factor analysis. The determinants of cluster activities are modelled using regression analysis. The effects of industry, place and respondents' entrepreneurial characteristics are used as exogenous variables. The study finds that industry does seem to be more important than place in the determination of networking and cooperative cluster activities, and that members of the wine tourism industry participate more in these activities than members of the tourism or hospitality industries. The addition of three variables that embody the entrepreneurial characteristics of the respondents approximately doubles the explanatory power of the original models. There is evidence to suggest that cluster activities are idiosyncratic for each industry-place cluster. The effects of firm size on cluster activities are also examined. No evidence is found of cooperative activities depending on cluster size. The main results support the contention that sunk costs are important in the determination of cluster activities.
Description:
Penetration of wind generation into power systems in recent years has greatly affected optimal power flow (OPF) because of the uncertain behavior of this new energy resource. In this research work, at first, a novel scenario generation approach is proposed to model wind power (WP) uncertainty. The proposed scenario generation approach includes construction of probability density function (PDF) pertaining to WP forecast error, segmentation of the PDF by an efficient clustering approach to obtain both the optimal number and the optimal arrangement of the clusters, and the generation of WP scenarios using the optimized clusters through roulette wheel mechanism. Secondly, this paper presents a new OPF framework based on DC network modeling for wind generation integrated power systems. Thirdly, a new out-of-sample analysis is presented to evaluate the long-run performance of the proposed OPF approach encountering various realizations of uncertain WPs. Finally, the performance of the proposed method for solving WP-integrated OPF problem is extensively illustrated on the IEEE 30-bus and the IEEE 118-bus test systems and compared with the performance of the deterministic method and the Weibull PDF method. These comparisons illustrate better performance of the proposed method, while it has reasonable computation times. •A new scenario generation approach is presented.•A new wind power integrated optimal power model is proposed.•A new out-of-sample analysis is presented.•The effectiveness of the proposed model is extensively illustrated.
Description:
An Internet of Multimedia Things (IoMT) architecture aims to provide a support for real-time multimedia applications by using wireless multimedia sensor nodes that are deployed for a long-term usage. These nodes are capable of capturing both multimedia and nonmultimedia data, and form a network known as Wireless Multimedia Sensor Network (WMSN). In a WMSN, underlying routing protocols need to provide an acceptable level of Quality of Service (QoS) support for multimedia traffic. In this paper, we propose a Seamless and Authorized Streaming (SAMS) framework for a cluster-based hierarchical WMSN. The SAMS uses authentication at different levels to form secured clusters. The formation of these clusters allows only legitimate nodes to transmit captured data to their Cluster Heads (CHs). Each node senses the environment, stores captured data in its buffer, and waits for its turn to transmit to its CH. This waiting may result in an excessive packet-loss and end-to-end delay for multimedia traffic. To address these issues, a channel allocation approach is proposed for an intercluster communication. In the case of a buffer overflow, a member node in one cluster switches to a neighboring CH provided that the latter has an available channel for allocation. The experimental results show that the SAMS provides an acceptable level of QoS and enhances security of an underlying network.
Description:
The concept of Internet of Multimedia Things (IoMT) is becoming popular nowadays and can be used in various smart city applications, e.g., traffic management, healthcare, and surveillance. In the IoMT, the devices, e.g., Multimedia Sensor Nodes (MSNs), are capable of generating both multimedia and non-multimedia data. The generated data are forwarded to a cloud server via a Base Station (BS). However, it is possible that the Internet connection between the BS and the cloud server may be temporarily down. The limited computational resources restrict the MSNs from holding the captured data for a longer time. In this situation, mobile sinks can be utilized to collect data from MSNs and upload to the cloud server. However, this data collection may create privacy issues, such as revealing identities and location information of MSNs. Therefore, there is a need to preserve the privacy of MSNs during mobile data collection. In this paper, we propose an efficient privacy-preserving-based data collection and analysis (P2DCA) framework for IoMT applications. The proposed framework partitions an underlying wireless multimedia sensor network into multiple clusters. Each cluster is represented by a Cluster Head (CH). The CHs are responsible to protect the privacy of member MSNs through data and location coordinates aggregation. Later, the aggregated multimedia data are analyzed on the cloud server using a counter-propagation artificial neural network to extract meaningful information through segmentation. Experimental results show that the proposed framework outperforms the existing privacy-preserving schemes, and can be used to collect multimedia data in various IoMT applications.