937 resultados para Oscillations-Stars


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The 31st TTRA conference was held in California’s San Fernando Valley, home of Hollywood and Burbank’s movie and television studios. The twin themes of Hollywood and the new Millennium promised and delivered “something old, yet something new”. The meeting offered a historical summary, not only of the year in review but also of many features of travel research since the first literature in the field appeared in the 1970s. Also, the millennium theme set the scene for some stimulating and forward thinking discussions. The Hollywood location offered an opportunity to ponder on the value of the movie-induced tourism for Los Angeles, at a time when Hollywood Boulevard was in the midst of a much needed redevelopment programme. Hollywood Chamber of Commerce speaker Oscar Arslanian acknowledged that the face of the famous district had become tired, and that its ability to continue to attract visitors in the future lay in redeveloping its past heritage. In line with the Hollywood theme a feature of the conference was a series of six special sessions with “Stars of Travel Research”. These sessions featured: Clare Gunn, Stanley Plog, Charles Gouldner, John Hunt, Brent Ritchie, Geoffrey Crouch, Peter Williams, Douglas Frechtling, Turgut Var, Robert Christie-Mill, and John Crotts. Delegates were indeed privileged to hear from many of the pioneers of tourism research. Clare Gunn, Charles Goeldner, Turgut Var and Stanley Plog, for example, traced the history of different aspects of the tourism literature, and in line with the millennium theme, offered some thought provoking discussion on the future challenges facing tourism. These included; the commodotisation of airlines and destinations, airport and traffic congestion, environment sustainability responsibility and the looming burst of the baby-boomer bubble. Included in the conference proceedings are four papers presented by five of the “Stars”. Brent Ritchie and Geoffrey Crouch discuss the critical success factors for destinations, Clare Gunn shares his concerns about tourism being a smokestack industry, Doug Frechtling provides forecasts of outbound travel from 20 countries, and Charles Gouldner, who has attended all 31 TTRA conferences, reflects on the changes that have taken place in tourism research over 35 years...

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Despite being set in an unnamed Texan city, Ghost Rider (Mark Steven Johnson, 2007) was a landmark film for Melbourne. It was the first international production to be made at the Central City (now Docklands) Studios, much to the relief of the heavily-invested state government. And it demonstrated to the world (or more importantly, to producers resident in a small part of southern California), that the city was willing and available to be made over and made up to fit even (especially!) the most stupid filmmaking fantasies. Announcing the imminent arrival of the production in October 2004, the Herald Sun boldly predicted that '[c]ity lanes, Telstra Dome and the Yarra River will be the stars of the new action film'. In fact Melbourne is, as the filmmakers intended, (virtually) unidentifiable onscreen. For the Victorian State government, Ausfilm, Film Victoria and the Melbourne Film Office, this lack of specificity was something to be celebrated; a few months before Ghost Rider went in to production, the then State Minister for Innovation, John Brumby, declared that 'it's almost inconceivable that [Ghost Rider] won't put Melbourne on the map internationally'.

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This paper illustrates robust fixed order power oscillation damper design for mitigating power systems oscillations. From implementation and tuning point of view, such low and fixed structure is common practice for most practical applications, including power systems. However, conventional techniques of optimal and robust control theory cannot handle the constraint of fixed-order as it is, in general, impossible to ensure a target closed-loop transfer function by a controller of any given order. This paper deals with the problem of synthesizing or designing a feedback controller of dynamic order for a linear time-invariant plant for a fixed plant, as well as for an uncertain family of plants containing parameter uncertainty, so that stability, robust stability and robust performance are attained. The desired closed-loop specifications considered here are given in terms of a target performance vector representing a desired closed-loop design. The performance of the designed controller is validated through non-linear simulations for a range of contingencies.

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In natural waterways and estuaries, the understanding of turbulent mixing is critical to the knowledge of sediment transport, stormwater runoff during flood events, and release of nutrient-rich wastewater into ecosystems. In the present study, some field measurements were conducted in a small subtropical estuary with micro-tidal range and semi-diurnal tides during king tide conditions: i. e., the tidal range was the largest for both 2009 and 2010. The turbulent velocity measurements were performed continuously at high-frequency (50Hz) for 60 h. Two acoustic Doppler velocimeters (ADVs) were sampled simultaneously in the middle estuarine zone, and a third ADV was deployed in the upper estuary for 12 h only. The results provided an unique characterisation of the turbulence in both middle and upper estuarine zones under the king tide conditions. The present observations showed some marked differences between king tide and neap tide conditions. During the king tide conditions, the tidal forcing was the dominant water exchange and circulation mechanism in the estuary. In contrast, the long-term oscillations linked with internal and external resonance played a major role in the turbulent mixing during neap tides. The data set showed further that the upper estuarine zone was drastically less affected by the spring tide range: the flow motion remained slow, but the turbulent velocity data were affected by the propagation of a transient front during the very early flood tide motion at the sampling site. © 2012 Springer Science+Business Media B.V.

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This paper presents a new approach to the design of a rough fuzzy controller for the control loop of the SVC (static VAR system) in a two area power system for stability enhancement with particular emphasis on providing effective damping for oscillatory instabilities. The performances of the rough fuzzy and the conventional fuzzy controller are compared with that of the conventional PI controller for a variety of transient disturbances, highlighting the effectiveness of the rough fuzzy controller in damping the inter-area oscillations. The effect of the rough fuzzy controller in improving the CCT (critical clearing time) of the two area system is elaborated in this paper as well.

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This paper provides an analysis of why many ‘stars’ tend to fade away rather than enjoying ongoing branding advantages from their reputations. We propose a theory of market overshooting in creative industries that is based on Schumpeterian competition between producers to maintain the interest of boundedly rational fans. As creative producers compete by offering further artistic novelty, this escalation of product complexity eventually leads to overshooting. We propose this as a theory of endogenous cycles in the creative industries.

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During a major flood event, the inundation of urban environments leads to some complicated flow motion most often associated with significant sediment fluxes. In the present study, a series of field measurements were conducted in an inundated section of the City of Brisbane (Australia) about the peak of a major flood in January 2011. Some experiments were performed to use ADV backscatter amplitude as a surrogate estimate of the suspended sediment concentration (SSC) during the flood event. The flood water deposit samples were predominantly silty material with a median particle size about 25 μm and they exhibited a non-Newtonian behavior under rheological testing. In the inundated urban environment during the flood, estimates of suspended sediment concentration presented a general trend with increasing SSC for decreasing water depth. The suspended sediment flux data showed some substantial sediment flux amplitudes consistent with the murky appearance of floodwaters. Altogether the results highlighted the large suspended sediment loads and fluctuations in the inundated urban setting associated possibly with a non-Newtonian behavior. During the receding flood, some unusual long-period oscillations were observed (periods about 18 min), although the cause of these oscillations remains unknown. The field deployment was conducted in challenging conditions highlighting a number of practical issues during a natural disaster.

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The legend of Hunter S. Thompson*the great gonzo*has grown deeper and more layered since his death in February 2005 than it was even in his exotic and controversyfilled life. The most recent addition to the mythology*The Rum Diary(Bruce Robinson, 2011)*stars Johnny Depp, possibly Thompson’s greatest fan, and certainly a man dedicated to keeping the man’s memory alive. Not for the first time, Depp brings his A-list status and good looks to playing the Thompson character on the big screen. In Terry Gilliam’s adaptation of Fear and Loathing in Las Vegas (1998) he played the writer’s alter ego, Raoul Duke. Duke was Thompson, and Fear and Loathing in Las Vegas a fictionalized account of what is generally accepted to have been a real-life episode. In The Rum Diary he plays Paul Kemp, the young journalist who lands a job as a crime reporter on a struggling Puerto Rican newspaper. Again, the protagonist is a version of Thompson himself, who did indeed spend time in 1960 working for the Puerto Rican press. Both films join Gonzo (Alex Gibney, 2008) to form a trilogy of Depp-infused movies about a journalist some regard as one of the greatest of the twentieth century, and others view as an overrated charlatan who leveraged his one big idea into a four decades-long career brought low by drugs, booze, dysfunctional sex and, finally, Hemingwayesque despair...

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To ensure the small-signal stability of a power system, power system stabilizers (PSSs) are extensively applied for damping low frequency power oscillations through modulating the excitation supplied to synchronous machines, and increasing interest has been focused on developing different PSS schemes to tackle the threat of damping oscillations to power system stability. This paper examines four different PSS models and investigates their performances on damping power system dynamics using both small-signal eigenvalue analysis and large-signal dynamic simulations. The four kinds of PSSs examined include the Conventional PSS (CPSS), Single Neuron based PSS (SNPSS), Adaptive PSS (APSS) and Multi-band PSS (MBPSS). A steep descent parameter optimization algorithm is employed to seek the optimal PSS design parameters. To evaluate the effects of these PSSs on improving power system dynamic behaviors, case studies are carried out on an 8-unit 24-bus power system through both small-signal eigenvalue analysis and large-signal time-domain simulations.

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An important component of current models for interstellar and circumstellar evolution is the infrared (IR)spectral data collected from stellar outflows around oxygen-rich stars and from the general interstellar medium [1]. IR spectra from these celestial bodies are usually interpreted as showing the general properties of sub-micron sized silicate grains [2]. Two major features at 10 and 20 microns are reasonably attributed to amorphous olivine or pyroxene (e.g. Mg2Si04 or MgSi03) on the basis of comparisons with natural standards and vapor condensed silicates [3-6]. In an attempt to define crystallisation rates for spectrally amorphous condensates, Nuth and Donn [5] annealed experimentally produced amorphous magnesium silicate smokes at 1000K. On analysing these smokes at various annealing times, Nuth and Donn [5] showed that changes in crystallinity measured by bulk X-ray diffraction occured at longer annealing times (days) than changes measured by IR spectra (a few hours). To better define the onset of crystallinity in these magnesium silicates, we have examined each annealed product using a JEOL 1OOCX analytical electron microscope (AEM). In addition, the development of chemical diversity with annealing has been monitored using energy dispersive spectroscopy of individual grains from areas <20nm in diameter. Furthermore, the crystallisation kinetics of these smokes under ambient, room temperature conditions have been examined using bulk and fourier transform infrared (FTIR)spectra.

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Research background: For decades the Chuck Taylor All Star basketball shoe (first designed in 1921 by Converse, an American shoe company), has been an iconic item of fashion apparel, particularly for the youth oriented market - as a form of self expression and identify, adolescents have for generations been customising their Converse sneakers to create innovative and unique footwear. Although originally developed purely for sport, sneakers gradually crossed over into fashion and the majority of athletic shoes are now purchased for street fashion or leisure wear. Artisan Gallery (Brisbane), in conjunction with the exhibition Reboot: Function, Fashion and the Sneaker, a history of the sneaker, selected 20 designers to customise and re-design the classic Converse Chuck Taylor All Stars shoe and in doing so highlighted the diversity of forms possible for creative outcomes. As Artisan Gallery Curator Kirsten Fitzpatrick states “the ‘sports show’, designed to coincide with the Olympics, is also about exploring the sneaker as a platform for creativity... and (one) of the more bazaar creations was Dean Brough's deconstructed shoes to make men’s underwear.” The exhibition ran from 21 June – 16 August 2012: http://artisan-ideaskillproduct.blogspot.com.au/2012/06/converse-blank-canvas-project.html Research question: Even though the sneaker is a fashion item, it still is fundamentally used for foot protection and historically was aligned to ball sports, principally Basketball - as a fashion designers/practitioner how can I connect (in a whimsical manner) this history of usage for ball sports to the sneaker and re-design and re-use all the physical elements of the shoe to produce a unique wearable item of clothing - the selected medium for this challenge and experimentation was the classic archetypal men’s white boxer shorts. Artisan Statement BALLS UP - The Converse Sneaker, it’s almost impossible to imagine a better rounded item to maintain peak performance for all types of ball sports. Gentlemen, your other most precious balls also deserve this level of comfort and support to sustain the hard times – the Converse Boxer, balls up, bats out, get ready to play hard. Research contribution: The project highlighted some of the unique and diverse creative manifestations that are possible from the classic sneaker. From a fashion practitioners’ perspective, the design outcomes (men’s boxer short made from converse sneakers) demonstrated the strong association to iconic fashion apparel, and recognised the connection to wearability and comfort that is requisite in both footwear and men’s underwear. Research significance: The exhibition was viewed by in excess of 1000 people and generated exceptional media coverage and public exposure/impact. As Artisan Gallery Curator Kirsten Fitzpatrick states “20 of Brisbane's best designers were given the opportunity to customise their own Converse Sneakers, with The Converse Blank Canvas Project.” And to be selected in this category demonstrates the calibre of importance for design prominence.

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Peggy Shaw has always had a host of crooners, lounge singers, movie stars, rock and roll bands, and eccentric family members living inside her. Ruff is a tribute to those who have kept Shaw company over the last 68 years, a lament for the absence of those who disappeared into the dark holes left behind by her recent stroke, and a celebration that her brain is able to fill the blank green screens with new insight. The original set and media environment for RUFF was conceived during a Split Britches residency hosted at QUT from June-August 2012, funded by Arts Queensland. After a preliminary season at Out North in Alaska RUFF premiered at Performance Space 122 2013 COIL festival, PS122 @ Dixon Place, New York in January 2013 and has since toured to the Chelsea Theatre in London and the Arches Festival in Glasgow. Co Written and Performed by Peggy Shaw, Co Written and Directed by Lois Weaver, Original Music Composed by Vivian Stoll, Choreography by Stormy Brandenburger, Set and Media Design by Matt Delbridge, Lighting Design by Lori E Said.

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Power system stabilizer (PSS) is one of the most important controllers in modern power systems for damping low frequency oscillations. Many efforts have been dedicated to design the tuning methodologies and allocation techniques to obtain optimal damping behaviors of the system. Traditionally, it is tuned mostly for local damping performance, however, in order to obtain a globally optimal performance, the tuning of PSS needs to be done considering more variables. Furthermore, with the enhancement of system interconnection and the increase of system complexity, new tools are required to achieve global tuning and coordination of PSS to achieve optimal solution in a global meaning. Differential evolution (DE) is a recognized as a simple and powerful global optimum technique, which can gain fast convergence speed as well as high computational efficiency. However, as many other evolutionary algorithms (EA), the premature of population restricts optimization capacity of DE. In this paper, a modified DE is proposed and applied for optimal PSS tuning of 39-Bus New-England system. New operators are introduced to reduce the probability of getting premature. To investigate the impact of system conditions on PSS tuning, multiple operating points will be studied. Simulation result is compared with standard DE and particle swarm optimization (PSO).

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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.

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This paper focuses on the implementation of the TS (Tagaki-Sugino) fuzzy controller for the active power and the DC capacitor voltage control of the Doubly Fed Induction Generator (DFIG) based wind generator. DFIG system is represented by a third-order model where electromagnetic transients of the stator are neglected. The effectiveness of the TS-fuzzy controller on the rotor speed oscillations and the DC capacitor voltage variations of the DFIG damping controller on converter ratings of the DFIG system is also investigated. The results of the time domain simulation studies are presented to elucidate the effectiveness of the TS-fuzzy controller compared with conventional PI controller in the DFIG system. The proposed TS-fuzzy controller can improve the fault ride through capability of DFIG compared to the conventional PI controller