Power system stability enhancement in a deregulated environment using FACTS devices

In deregulated versions of free-market electricity, producers will be free to send power along other utilities. The price of power strongly depends and fluctuates according to mutual benefit index of both supplier and consumer. In such a situation, strong interaction among utilities may cause instabilities in the system. As the frequency of market-based dispatch increases market forces tend to destabilize the stable system dynamics depending on the value of Ks/τλ(market dependent parameter) ratio. This tends to destabilize the coupled dynamics. The implementation of TCSC can effectively damp the inter area modes of oscillations of the coupled market system.

Service condition of railroad corridors around the insulated rail joints

Railroad corridors contain large number of Insulated Rail Joints (IRJs) that act as safety critical elements in the circuitries of the signaling and broken rail identification systems. IRJs are regarded as sources of excitation for the passage of loaded wheels leading to high impact forces; these forces in turn cause dips, cross levels and twists to the railroad geometry in close proximity to the sections containing the IRJs in addition to the local damages to the railhead of the IRJs. Therefore, a systematic monitoring of the IRJs in railroad is prudent to mitigate potential risk of their sudden failure (e.g., broken tie plates) under the traffic. This paper presents a simple method of periodic recording of images using time-lapse photography and total station surveying measurements to understand the ongoing deterioration of the IRJs and their surroundings. Over a 500 day period, data were collected to examine the trends in narrowing of the joint gap due to plastic deformation the railhead edges and the dips, cross levels and twists caused to the railroad geometry due to the settlement of ties (sleepers) around the IRJs. The results reflect that the average progressive settlement beneath the IRJs is larger than that under the continuously welded rail, which leads to excessive deviation of railroad profile, cross levels and twists.

A variable stepsize implementation for stochastic differential equations

Stochastic differential equations (SDEs) arise from physical systems where the parameters describing the system can only be estimated or are subject to noise. Much work has been done recently on developing higher order Runge-Kutta methods for solving SDEs numerically. Fixed stepsize implementations of numerical methods have limitations when, for example, the SDE being solved is stiff as this forces the stepsize to be very small. This paper presents a completely general variable stepsize implementation of an embedded Runge Kutta pair for solving SDEs numerically; in this implementation, there is no restriction on the value used for the stepsize, and it is demonstrated that the integration remains on the correct Brownian path.

Regulating journalists? The Finkelstein Review, the Convergence Review, and News Media Regulation in Australia

This paper identifies two major forces driving change in media policy worldwide: media convergence, and renewed concerns about media ethics, with the latter seen in the U.K. Leveson Inquiry. It focuses on two major public inquiries in Australia during 2011-2012 – the Independent Media Inquiry (Finkelstein Review) and the Convergence Review – and the issues raised about future regulation of journalism and news standards. Drawing upon perspectives from media theory, it observes the strong influence of social responsibility theories of the media in the Finkelstein Review, and the adverse reaction these received from those arguing from Fourth Estate/free press perspectives, which were also consistent with the longstanding opposition of Australian newspaper proprietors to government regulation. It also discusses the approaches taken in the Convergence Review to regulating for news standards, in light of the complexities arising from media convergence. The paper concludes with consideration of the fast-changing environment in which such proposals to transform media regulation are being considered, including the crisis of news media organisation business models, as seen in Australia with major layoffs of journalists from the leading print media publications.

Factors affecting the stability analysis of earth dam slopes subjected to reservoir drawdown

The drawdown of reservoirs can significantly affect the stability of upstream slopes of earth dams. This is due to the removal of the balancing hydraulic forces acting on the dams and the undrained condition within the upstream slope soils. In such scenarios, the stability of the slopes can be influenced by a range of factors including drawdown rates, slope inclination and soil properties. This paper investigates the effects of drawdown rate, saturated hydraulic conductivity and unsaturated shear strength of dam materials on the stability of the upstream slope of an earth dam. In this study, the analysis of pore-water pressure changes within the upstream slope during reservoir drawdown was coupled with the slope stability analysis using the general limit equilibrium method. The results of the analysis suggested that a decrease in the reservoir water level caused the stability of the upstream slope to decrease. The dam embankment constructed with highly permeable soil was found to be more stable during drawdown scenarios, compared to others. Further, lower drawdown rates resulted in a higher safety factor for the upstream slope. Also, the safety factor of the slope calculated using saturated shear strength properties of the dam materials was slightly higher than that calculated using unsaturated shear strength properties. In general, for all the scenarios analysed, the lowest safety factor was found to be at the reservoir water level of about 2/3 of drawdown regime.

Impact of the internal business environment on knowledge management within construction organisations

Purpose: Recent knowledge management (KM) literature suggests that KM activities are influenced by the elements of the internal business environment (BE) of organisations. This paper attempts to provide some unique insights into the contextual input of the KM process through empirically identifying the major factors (i.e. “forces”) within the internal BE of construction organisations operating in Hong Kong, and investigating their impact on the intensity of KM activities. Design/methodology/approach: A questionnaire survey was administered to a sample of construction contractors operating in Hong Kong to elicit opinions on the internal BE and intensity of KM activities as executed by targeted organisations. A total of 149 usable responses were received from 99 organisations representing about 38 percent of the research population. In parallel, to the survey, a total of 15 semi-structured interviews were undertaken to provide more insights into the phenomenon under investigation. Findings: Supported by the empirical and qualitative evidence, this study established that firstly, both organisational and technical environments have the capacity to either positively or negatively impact the intensity of KM activities, and both environments serve as stimuli in increasing each other's dynamism; secondly, certain types of KM activities are stronger “energy receivers” and easily to be “powered up” by manipulating factors representing these two environments. Then, through interactions between KM activities, the intensity of the whole strategic KM cycle will be increased thus helping to strengthen organisational competitive advantage.

Perceptions of corporate social and environmental accounting and reporting practices from accountants in Bangladesh

Purpose – The aim of this study is to elicit accountants’ perceptions regarding corporate social and environmental accounting and reporting practices in a developing country such as Bangladesh. Design/methodology/approach – Members of the Institute of Chartered Accountants of Bangladesh (ICAB) were surveyed to determine their perceptions on issues pertaining to social and environmental accounting and reporting practices in Bangladesh. Findings – Whilst the findings show that accountants have positive attitudes toward corporate social and environmental accounting, progress is limited, with the absence of ICAB in making any noticeable effort to develop such practices. Research implications – Unlike prior studies, the implications of this study suggest that without international influence, it is less likely that institutional forces in Bangladesh (ICAB and the government) would be effective in dealing with social and environmental accounting and reporting issues. Originality/value – While prior studies advocate proactive roles of the accounting profession, this study argues that proactive roles are less likely to prevail in the context of Bangladesh without direct intervention from institutional and regulatory authorities in the international arena.

The doctrine of command responsibility in the midst of war : legal fallacy or reflection of reality

The history of war is blighted with astonishing reminders of man’s ability to cast his sense of humanity aside and inflict unspeakable harm upon one another. The ruthless bombing of Dresden, the callousness of the Nazi concentration camps and the massacre of the Tutsis are but a few of the atrocities that have haunted our past. In response to these atrocities, society has imposed an ever-increasing number of laws and rules to regulate warfare. Amongst these is the doctrine of command responsibility. The doctrine of command responsibility states that a commander is criminally liable for the crimes of his subordinates if he knew or should have known of their crimes. This paper will examine whether the doctrine is an appropriate and realistic legal standard to hold commanders accountable to or whether the doctrine is more a reflection of social sentiment and legal rhetoric. If the doctrine, and indeed the law of war in general, is unrealistic then the law cannot fulfil its purpose - that is, the prevention of atrocities. Instead of being solely a reflection of moral authority and social sentiments the law must also be a tool that guides and shapes the decisions and actions of the military through the chaotic and brutal nature of war...

Sediment-transport (wind) experiments in zero gravity

The carousel wind tunnel (CWT) can be a significant tool for the determination of the nature and magnitude of interparticlar forces at threshold of motion. By altering particle and drum surface electrical properties and/or by applying electric potential difference across the inner and outer drums, it should be possible to separate electrostatic effects from other forces of cohesion. Besides particle trajectory and bedform analyses, suggestions for research include particle aggregation in zero and sub-gravity environments, effect of suspension-saltation ratio on soil abrasion, and the effects of shear and shear free turbulence on particle aggregation as applied to evolution of solar nebula.

The emerging role of the Board of Directors in enterprise business technology governance

In an increasingly business technology (BT) dependent world, the impact of the extraordinary changes brought about by the nexus of mobile and cloud technologies, social media and big data is increasingly being felt in the board room. As leaders of enterprises of every type and size, board directors can no longer afford to ignore, delegate or avoid BT-related decisions. Competitive, financial and reputational risk is increased if boards fail to recognize their role in governing technology as an asset and in removing barriers to improving enterprise business technology governance (EBTG). Directors’ awareness of the need for EBTG is increasing. However, industry research shows that board level willingness to rectify the gap between awareness and action is very low or non-existent. This literature review-based research identifies barriers to EBTG effectiveness. It provides a practical starting point for board analysis. We offer four outcomes that boards might focus on to ensure the organizations they govern are not left behind by those led by the upcoming new breed of technology-savvy leaders. Most extant research looks backward for examples, examining data pre-2010, the time when a tipping point in the personal and business use of multimedia and mobile-internet devices significantly deepened the impacts of the identified nexus technology forces, and began rapidly changing the way many businesses engage with their customers, employees and stakeholders. We situate our work amidst these nexus forces, discuss the board’s role in EBTG in this context, and modernize current definitions of enterprise technology governance. The primary limitation faced is the lack of scholarly research relating to EBTG in the rapidly changing digital economy. Although we have used recent (2011 - 2013) industry surveys, the volume of these surveys and congruence across them is significant in terms of levels of increased awareness and calls for increased board attention and competency in EBTG and strategic information use. Where possible we have used scholarly research to illustrate or discuss industry findings.

Sport biomechanics

Biomechanics involves research and analysis of the mechanisms of living organisms. This can be conducted on multiple levels and represents a continuum from the molecular, wherein biomaterials such as collagen and elastin are considered, to the tissue, organ and whole body level. Some simple applications of Newtonian mechanics can supply correct approximations on each level, but precise details demand the use of continuum mechanics. Sport biomechanics uses the scientific methods of mechanics to study the effects of forces on the sports performer and considers aspects of the behaviour of sports implements, equipment, footwear and surfaces. There are two main aims of sport biomechanics, that is, the reduction of injury and the improvement of performance (Bartlett, 1999). Aristotle (384-322 BC) wrote the first book on biomechanics, De Motu Animalium, translated as On the Movement of Animals. He saw animals' bodies as mechanical systems, but also pursued questions that might explain the physiological difference between imagining the performance of an action and actually doing it. Some simple examples of biomechanics research include the investigation of the forces that act on limbs, the aerodynamics of animals in flight, the hydrodynamics of objects moving through water and locomotion in general across all forms of life, from individual cells to whole organisms...

Catalysing design principles through the dreaming of sustainable subtropical cityscapes : the collaborative construction of new place identities

This paper addresses the question of how to open up pathways and build capacity to facilitate the movement towards sustainable sub-tropical cities. The focus is on outlining a collaborative planning and co-design process that can help catalyse the emergence of sustainable place-habitats and so re-weave and colour anew the tapestry of our sub-tropical cities. Cities are portrayed as self-organising complex adaptive system phenomena, being constantly re-shaped by local and global social-political, environmental, cultural and economic forces as well as planning regimes. While constructing a sustainable city is at essence a design process incorporating new sustainable practices and legislation to reinforce their use, these steps are necessary but not sufficient. Sustainable sub-tropical city-making could be re-thought as a dreaming-re-storying process. This paper explores a new co-design process, which can channel collaborative efforts around re-inventing sustainable place-habitats across the cityscape. A further outcome of this co-design process is the alignment of the emergent design principles and planning actions that can trigger the re-storying of a new sustainable sub-tropical city. Besides a new co-design process, we also advocate the building of sub-tropical city learning networks to facilitate the cross-fertilization for Dreaming sustainable sub-tropical cities.

Integrating crowd-behavior modeling into military simulation using game technology

Crowds of noncombatants play a large and increasingly recognized role in modern military operations and often create substantial difficulties for the combatant forces involved. However, realistic models of crowds are essentially absent from current military simulations. To address this problem, the authors are developing a crowd simulation capable of generating crowds of noncombatant civilians that exhibit a variety of realistic individual and group behaviors at differing levels of fidelity. The crowd simulation is interoperable with existing military simulations using a standard, distributed simulation architecture. Commercial game technology is used in the crowd simulation to model both urban terrain and the physical behaviors of the human characters that make up the crowd. The objective of this article is to present the design and development process of a simulation that integrates commercially available game technology with current military simulations to generate realistic and believable crowd behavior.

Crowd modelling for military simulations using game technology

Crowds of non-combatants play a large and increasingly recognized role in modern military operations, and often create substantial difficulties for the combatant forces involved. However, realistic models of crowds are essentially absent from current military simulations. To address this problem we are developing a crowd simulation capable of generating crowds of non-combatant civilians that exhibit a variety of realistic individual and group behaviours at differing levels of fidelity. The crowd simulation is interoperable with existing military simulations using a standard distributed simulation architecture. Commercial game technology is utilized in the crowd simulation to model both urban terrain and the physical behaviours of the human characters that make up the crowd. The objective of this paper is to present the process involved with the design and development of a simulation that integrates commercially available game technology with current military simulations in order to generate realistic and believable crowd behaviour.

Construction Prices : the Market Effect

Teachers of construction economics and estimating have for a long time recognised that there is more to construction pricing than detailed calculation of costs (to the contractor). We always get to the point where we have to say "of course, experience or familiarity of the market is very important and this needs judgement, intuition, etc". Quite how important is the matter in construction pricing is not known and we tend to trivialise its effect. If judgement of the market has a minimal effect, little harm would be done, but if it is really important then some quite serious consequences arise which go well beyond the teaching environment. Major areas of concern for the quantity surveyor are in cost modelling and cost planning - neither of which pay any significant attention to the market effect. There are currently two schools of thought about the market effect issue. The first school is prepared to ignore possible effects until more is known. This may be called the pragmatic school. The second school exists solely to criticise the first school. We will call this the antagonistic school. Neither the pragmatic nor the antagonistic schools seem to be particularly keen to resolve the issue one way or the other. The founder and leader of the antagonistic school is Brian Fine whose paper in 1974 is still the basic text on the subject, and in which he coined the term 'socially acceptable' price to describe what we now recognise as the market effect. Mr Fine's argument was then, and is since, that the uncertainty surrounding the contractors' costing and cost estimating process is such that the uncertainty surrounding the contractors' cost that it logically leads to a market-orientated pricing approach. Very little factual evidence, however, seems to be available to support these arguments in any conclusive manner. A further, and more important point for the pragmatic school, is that, even if the market effect is as important as Mr Fine believes, there are no indications of how it can be measured, evaluated or predicted. Since 1974 evidence has been accumulating which tends to reinforce the antagonists' view. A review of the literature covering both contractors' and designers' estimates found many references to the use of value judgements in construction pricing (Ashworth & Skitmore, 1985), which supports the antagonistic view in implying the existence of uncertainty overload. The most convincing evidence emerged quite by accident in some research we recently completed with practicing quantity surveyors in estimating accuracy (Skitmore, 1985). In addition to demonstrating that individual quantity surveyors and certain types of buildings had significant effect on estimating accuracy, one surprise result was that only a very small amount of information was used by the most expert surveyors for relatively very accurate estimates. Only the type and size of building, it seemed, was really relevant in determining accuracy. More detailed information about the buildings' specification, and even a sight to the drawings, did not significantly improve their accuracy level. This seemed to offer clear evidence that the constructional aspects of the project were largely irrelevant and that the expert surveyors were somehow tuning in to the market price of the building. The obvious next step is to feed our expert surveyors with more relevant 'market' information in order to assess its effect. The problem with this is that our experts do not seem able to verbalise their requirements in this respect - a common occurrence in research of this nature. The lack of research into the nature of market effects on prices also means the literature provides little of benefit. Hence the need for this study. It was felt that a clearer picture of the nature of construction markets would be obtained in an environment where free enterprise was a truly ideological force. For this reason, the United States of America was chosen for the next stage of our investigations. Several people were interviewed in an informal and unstructured manner to elicit their views on the action of market forces on construction prices. Although a small number of people were involved, they were thought to be reasonably representative of knowledge in construction pricing. They were also very well able to articulate their views. Our initial reaction to the interviews was that our USA subjects held very close views to those held in the UK. However, detailed analysis revealed the existence of remarkably clear and consistent insights that would not have been obtained in the UK. Further evidence was also obtained from literature relating to the subject and some of the interviewees very kindly expanded on their views in later postal correspondence. We have now analysed all the evidence received and, although a great deal is of an anecdotal nature, we feel that our findings enable at least the basic nature of the subject to be understood and that the factors and their interrelationships can now be examined more formally in relation to construction price levels. I must express my gratitude to the Royal Institution of Chartered Surveyors' Educational Trust and the University of Salford's Department of Civil Engineering for collectively funding this study. My sincere thanks also go to our American participants who freely gave their time and valuable knowledge to us in our enquiries. Finally, I must record my thanks to Tim and Anne for their remarkable ability to produce an intelligible typescript from my unintelligible writing.