966 resultados para Distributed leadership
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In this paper we report on the qualitative component of a study that explored middle level academic leaders’ experiences of (un)ethical practices and ethical dilemmas in their daily work. An electronic survey was distributed to academic leaders from universities across three Australian states. There are three major findings in this study. First, the messy context of universities is providing a fertile ground for ethical dilemmas to flourish. Second, the two main categories of unethical practices identified by participants were academic dishonesty and inappropriate behaviour towards staff and students. Third, the ethical dilemmas that emerged focused on the academic leaders’ strong sense of professional ethics that were in conflict with an ethic of care, supervisors’ directives, and the rules and policies of the organisation.
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Distributed space-time coding (DSTC) exploits the concept of cooperative diversity and space-time coding to offer a powerful bandwidth efficient solution with improved diversity. In this paper, we evaluate the performance of DSTC with slotted amplify-and-forward protocol (SAF). Relay nodes between the source and the destination nodes are grouped into two relay clusters based on their respective locations and these relay clusters cooperate to transmit the space-time coded signal to the destination node in different time frames. We further extend the proposed Slotted-DSTC to Slotted DSTC with redundant code (Slotted-DSTC-R) protocol where the relay nodes in both relay clusters forward the same space-time coded signal to the destination node to achieve a higher diversity order.
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The behaviour of single installations of solar energy systems is well understood; however, what happens at an aggregated location, such as a distribution substation, when output of groups of installations cumulate is not so well understood. This paper considers groups of installations attached to distributions substations on which the load is primarily commercial and industrial. Agent-based modelling has been used to model the physical electrical distribution system and the behaviour of equipment outputs towards the consumer end of the network. The paper reports the approach used to simulate both the electricity consumption of groups of consumers and the output of solar systems subject to weather variability with the inclusion of cloud data from the Bureau of Meteorology (BOM). The data sets currently used are for Townsville, North Queensland. The initial characteristics that indicate whether solar installations are cost effective from an electricity distribution perspective are discussed.
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Given the paradigm of smart grid as the promising backbone for future network, this paper uses this paradigm to propose a new coordination approach for LV network based on distributed control algorithm. This approach divides the LV network into hierarchical communities where each community is controlled by a control agent. Different level of communication has been proposed for this structure to control the network in different operation modes.
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This paper explores grassroots leadership, an under-researched and often side-lined approach to leadership that operates outside of formal bureaucratic structures. The paper’s central purpose is the claim that an understanding of grassroots leadership and tactics used by grassroots leaders provides valuable insights for the study of school leadership. In this paper, we present and discuss an original model of grassroots leadership based on the argument that this under-researched area can further our understanding of school leadership. Drawing upon the limited literature in the field, we present a model consisting of two approaches to change (i.e. conflict and consensus) and two categories of change (i.e. reform and refinement) and then provide illustrations of how the model works in practice. We make the argument that the model has much merit for conceptualizing school leadership, and this is illustrated by applying the model to formal bureaucratic leadership within school contexts. Given the current climate in education where business and management language is pervasive within leadership-preparation programs, we argue that it is timely for university academics, who are responsible for preparing school leaders to consider broadening their approach by exposing school leaders to a variety of change-based strategies and tactics used by grassroots leaders.
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Background Failure to convey time-critical information to team members during surgery diminishes members’ perception of the dynamic information relevant to their task, and compromises shared situational awareness. This research reports the dialog around clinical decisions made by team members in the time-pressured and high-risk context of surgery, and the impact of these communications on shared situational awareness. Methods Fieldwork methods were used to capture the dynamic integration of individual and situational elements in surgery that provided the backdrop for clinical decisions. Nineteen semi structured interviews were performed with 24 participants from anaesthesia, surgery, and nursing in the operating rooms of a large metropolitan hospital in Queensland, Australia. Thematic analysis was used. Results: The domain “coordinating decisions in surgery” was generated from textual data. Within this domain, three themes illustrated the dialog of clinical decisions, i.e., synchronizing and strategizing actions, sharing local knowledge, and planning contingency decisions based on priority. Conclusion Strategies used to convey decisions that enhanced shared situational awareness included the use of “self-talk”, closed-loop communications, and “overhearing” conversations that occurred at the operating table. Behaviours’ that compromised a team’s shared situational awareness included tunnelling and fixating on one aspect of the situation.
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Leadership change formed the backdrop to the 2010 Australian federal election, with the replacement of Kevin Rudd as prime minister by Julia Gillard, the country’s first female prime minister. This article uses the 2010 Australian Election Study, a post-election survey of voters, to examine patterns of voter defection between the 2007 and 2010 elections. The results show that the predominant influence on defection was how voters rated the leaders. Julia Gillard was particularly popular among female voters and her overall impact on the vote was slightly greater than that of Tony Abbott. Policy issues were second in importance after leadership, particularly for those moving from the Coalition to Labor, who were concerned about health and unemployment. Labor defectors to the Greens particularly disliked Labor’s education policies. Overall, the results point to the enduring importance of leaders as the predominant influence on how voters cast their ballot.
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In this paper we investigate the distribution of the product of Rayleigh distributed random variables. Considering the Mellin-Barnes inversion formula and using the saddle point approach we obtain an upper bound for the product distribution. The accuracy of this tail-approximation increases as the number of random variables in the product increase.
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The well-established under-frequency load shedding (UFLS) is deemed to be the last of effective remedial measures against a severe frequency decline of a power system. With the ever-increasing size of power systems and the extensive penetration of distributed generators (DGs) in power systems, the problem of developing an optimal UFLS strategy is facing some new challenges. Given this background, an optimal UFLS strategy for a distribution system with DGs and load static characteristics taken into consideration is developed. Based on the frequency and the rate of change of frequency, the presented strategy consists of several basic rounds and a special round. In the basic round, the frequency emergency can be alleviated by quickly shedding some loads. In the special round, the frequency security can be maintained, and the operating parameters of the distribution system can be optimized by adjusting the output powers of DGs and some loads. The modified IEEE 37-node test feeder is employed to demonstrate the essential features of the developed optimal UFLS strategy in the MATLAB/SIMULINK environment.
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This article explores the role of principal leadership in creating a thinking school. It contributes to the school leadership literature by exploring the intersection of two important areas of study in education - school leadership and education for thinking - which is a particularly apt area of study, because effective school leadership is crucial if students are to learn to be critical and creative thinkers, yet this connection has not be widely investigated. We describe how one principal, Hinton, turned around an underperforming school by using critical and creative philosophical thinking as the focus for students, staff and parents. Then, drawing on the school leadership literature, the article describes seven attributes of school leadership beginning with four articulated by Leithwood and colleagues (2006) (building vision and setting direction; redesigning the organisation; understanding and developing people; managing the teaching and learning program), and adding three others (influence; self-development; and responding to context). This framework is then used in a case study format in a collaboration between practitioner and researchers to first explore evidence from empirical studies and personal reflection about Hinton's leadership of Buranda State School, and second to illuminate how these general features of school leadership apply to creating a thinking school. Based on the case study and using the general characteristics of school leadership, a framework for leading a thinking school is described. Because the framework is based on a turnaround school, this framework has wide applicability: to schools that are doing well as an indication of how to implement a contemporary approach to curriculum and pedagogy; and to schools that are underperforming and want a rigorous, high expectation and contemporary way to improve student learning.
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Secure communications in distributed Wireless Sensor Networks (WSN) operating under adversarial conditions necessitate efficient key management schemes. In the absence of a priori knowledge of post-deployment network configuration and due to limited resources at sensor nodes, key management schemes cannot be based on post-deployment computations. Instead, a list of keys, called a key-chain, is distributed to each sensor node before the deployment. For secure communication, either two nodes should have a key in common in their key-chains, or they should establish a key through a secure-path on which every link is secured with a key. We first provide a comparative survey of well known key management solutions for WSN. Probabilistic, deterministic and hybrid key management solutions are presented, and they are compared based on their security properties and re-source usage. We provide a taxonomy of solutions, and identify trade-offs in them to conclude that there is no one size-fits-all solution. Second, we design and analyze deterministic and hybrid techniques to distribute pair-wise keys to sensor nodes before the deployment. We present novel deterministic and hybrid approaches based on combinatorial design theory and graph theory for deciding how many and which keys to assign to each key-chain before the sensor network deployment. Performance and security of the proposed schemes are studied both analytically and computationally. Third, we address the key establishment problem in WSN which requires key agreement algorithms without authentication are executed over a secure-path. The length of the secure-path impacts the power consumption and the initialization delay for a WSN before it becomes operational. We formulate the key establishment problem as a constrained bi-objective optimization problem, break it into two sub-problems, and show that they are both NP-Hard and MAX-SNP-Hard. Having established inapproximability results, we focus on addressing the authentication problem that prevents key agreement algorithms to be used directly over a wireless link. We present a fully distributed algorithm where each pair of nodes can establish a key with authentication by using their neighbors as the witnesses.
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Kuwait is an oil rich country planning for a future that is not dependent on exploiting natural resources. A major policy initiative has been the introduction of Information Communication and Technology (ICT) to schools. However, contextual issues and teacher capabilities in the use of ICT have limited the success of this initiative. The study examines the leadership strategies of two secondary school principals whose schools have achieved this goal. The case study draws on intensive data collected through interviews of the principals, and teachers supported by document analysis and observations. Analysis was guided by theoretical perspectives drawn from the literature which identified a range of strategies used by the principals to manage change. The principals of Schools A and B employed three key strategies to maximise the impact on the teaching staff incorporating ICT into their teaching and learning practices. These strategies were: (a) encouragement for teaching staff to implement ICT in their teaching; (b) support to meet the material and human needs of teaching staff using ICT; and (c) provision of instructions and guidance for teaching staff in how and why such behaviours and practices should be performed. The outcome of this study proposes an innovative change leadership model that informs emerging countries, which are also undergoing major change related to ICT. However, the study also revealed limitations in the implementation of ICT in the classroom and provides insights into further strategies that principals need to adopt.
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This paper describes the implementation of the first portable, embedded data acquisition unit (BabelFuse) that is able to acquire and timestamp generic sensor data and trigger General Purpose I/O (GPIO) events against a microsecond-accurate wirelessly-distributed ‘global’ clock. A significant issue encountered when fusing data received from multiple sensors is the accuracy of the timestamp associated with each piece of data. This is particularly important in applications such as Simultaneous Localisation and Mapping (SLAM) where vehicle velocity forms an important part of the mapping algorithms; on fast-moving vehicles, even millisecond inconsistencies in data timestamping can produce errors which need to be compensated for. The timestamping problem is compounded in a robot swarm environment especially if non-deterministic communication hardware (such as IEEE-802.11-based wireless) and inaccurate clock synchronisation protocols are used. The issue of differing timebases makes correlation of data difficult and prevents the units from reliably performing synchronised operations or manoeuvres. By utilising hardware-assisted timestamping, clock synchronisation protocols based on industry standards and firmware designed to minimise indeterminism, an embedded data acquisition unit capable of microsecond-level clock synchronisation is presented.
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The nonprofit funding landscape is in flux. Many organisations are having to think differently and develop fresh skills either to enter the fundraising market or to cope better with rising competition for community and corporate support. This new reality affects boards, CEOs and fundraisers alike. Against this backdrop, our exploratory study aimed to build an evidence base and spark more discussion about: - the role Australian nonprofit CEOs and boards play in supporting fundraising/development; - current engagement levels; and - perceptions of leadership in fundraising from two possibly contrasting perspectives: NP leaders (board members and CEOs); and fundraisers. This research has been supported by the Perpetual Foundation, the EF and SL Gluyas Trust and the Edward Corbould Charitable Trust under the management of Perpetual Trustee Company Ltd.
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In this paper, the shape design optimisation using morphing aerofoil/wing techniques, namely the leading and/or trailing edge deformation of a natural laminar flow RAE 5243 aerofoil is investigated to reduce transonic drag without taking into account of the piezo actuator mechanism. Two applications using a Multi-Objective Genetic Algorithm (MOGA)coupled with Euler and boundary analyser (MSES) are considered: the first example minimises the total drag with a lift constraint by optimising both the trailing edge actuator position and trailing edge deformation angle at a constant transonic Mach number (M! = 0.75)and boundary layer transition position (xtr = 45%c). The second example consists of finding reliable designs that produce lower mean total drag (μCd) and drag sensitivity ("Cd) at different uncertainty flight conditions based on statistical information. Numerical results illustrate how the solution quality in terms of mean drag and its sensitivity can be improved using MOGA software coupled with a robust design approach taking account of uncertainties (lift and boundary transition positions) and also how transonic flow over aerofoil/wing can be controlled to the best advantage using morphing techniques.