Adaptive cache aware multiprocessor scheduling framework

Computer resource allocation represents a significant challenge particularly for multiprocessor systems, which consist of shared computing resources to be allocated among co-runner processes and threads. While an efficient resource allocation would result in a highly efficient and stable overall multiprocessor system and individual thread performance, ineffective poor resource allocation causes significant performance bottlenecks even for the system with high computing resources. This thesis proposes a cache aware adaptive closed loop scheduling framework as an efficient resource allocation strategy for the highly dynamic resource management problem, which requires instant estimation of highly uncertain and unpredictable resource patterns. Many different approaches to this highly dynamic resource allocation problem have been developed but neither the dynamic nature nor the time-varying and uncertain characteristics of the resource allocation problem is well considered. These approaches facilitate either static and dynamic optimization methods or advanced scheduling algorithms such as the Proportional Fair (PFair) scheduling algorithm. Some of these approaches, which consider the dynamic nature of multiprocessor systems, apply only a basic closed loop system; hence, they fail to take the time-varying and uncertainty of the system into account. Therefore, further research into the multiprocessor resource allocation is required. Our closed loop cache aware adaptive scheduling framework takes the resource availability and the resource usage patterns into account by measuring time-varying factors such as cache miss counts, stalls and instruction counts. More specifically, the cache usage pattern of the thread is identified using QR recursive least square algorithm (RLS) and cache miss count time series statistics. For the identified cache resource dynamics, our closed loop cache aware adaptive scheduling framework enforces instruction fairness for the threads. Fairness in the context of our research project is defined as a resource allocation equity, which reduces corunner thread dependence in a shared resource environment. In this way, instruction count degradation due to shared cache resource conflicts is overcome. In this respect, our closed loop cache aware adaptive scheduling framework contributes to the research field in two major and three minor aspects. The two major contributions lead to the cache aware scheduling system. The first major contribution is the development of the execution fairness algorithm, which degrades the co-runner cache impact on the thread performance. The second contribution is the development of relevant mathematical models, such as thread execution pattern and cache access pattern models, which in fact formulate the execution fairness algorithm in terms of mathematical quantities. Following the development of the cache aware scheduling system, our adaptive self-tuning control framework is constructed to add an adaptive closed loop aspect to the cache aware scheduling system. This control framework in fact consists of two main components: the parameter estimator, and the controller design module. The first minor contribution is the development of the parameter estimators; the QR Recursive Least Square(RLS) algorithm is applied into our closed loop cache aware adaptive scheduling framework to estimate highly uncertain and time-varying cache resource patterns of threads. The second minor contribution is the designing of a controller design module; the algebraic controller design algorithm, Pole Placement, is utilized to design the relevant controller, which is able to provide desired timevarying control action. The adaptive self-tuning control framework and cache aware scheduling system in fact constitute our final framework, closed loop cache aware adaptive scheduling framework. The third minor contribution is to validate this cache aware adaptive closed loop scheduling framework efficiency in overwhelming the co-runner cache dependency. The timeseries statistical counters are developed for M-Sim Multi-Core Simulator; and the theoretical findings and mathematical formulations are applied as MATLAB m-file software codes. In this way, the overall framework is tested and experiment outcomes are analyzed. According to our experiment outcomes, it is concluded that our closed loop cache aware adaptive scheduling framework successfully drives co-runner cache dependent thread instruction count to co-runner independent instruction count with an error margin up to 25% in case cache is highly utilized. In addition, thread cache access pattern is also estimated with 75% accuracy.

Music selection using a touch screen interface : effect of auditory and visual feedback on driving and usability

This study aimed to examine the effects on driving, usability and subjective workload of performing music selection tasks using a touch screen interface. Additionally, to explore whether the provision of visual and/or auditory feedback offers any performance and usability benefits. Thirty participants performed music selection tasks with a touch screen interface while driving. The interface provided four forms of feedback: no feedback, auditory feedback, visual feedback, and a combination of auditory and visual feedback. Performance on the music selection tasks significantly increased subjective workload and degraded performance on a range of driving measures including lane keeping variation and number of lane excursions. The provision of any form of feedback on the touch screen interface did not significantly affect driving performance, usability or subjective workload, but was preferred by users over no feedback. Overall, the results suggest that touch screens may not be a suitable input device for navigating scrollable lists.

Performance recordivity : studio music in a live context

A broad range of positions is articulated in the academic literature around the relationship between recordings and live performance. Auslander (2008) argues that “live performance ceased long ago to be the primary experience of popular music, with the result that most live performances of popular music now seek to replicate the music on the recording”. Elliott (1995) suggests that “hit songs are often conceived and produced as unambiguous and meticulously recorded performances that their originators often duplicate exactly in live performances”. Wurtzler (1992) argues that “as socially and historically produced, the categories of the live and the recorded are defined in a mutually exclusive relationship, in that the notion of the live is premised on the absence of recording and the defining fact of the recorded is the absence of the live”. Yet many artists perform in ways that fundamentally challenge such positions. Whilst it is common practice for musicians across many musical genres to compose and construct their musical works in the studio such that the recording is, in Auslander’s words, the ‘original performance’, the live version is not simply an attempt to replicate the recorded version. Indeed in some cases, such replication is impossible. There are well known historical examples. Queen, for example, never performed the a cappella sections of Bohemian Rhapsody because it they were too complex to perform live. A 1966 recording of the Beach Boys studio creation Good Vibrations shows them struggling through the song prior to its release. This paper argues that as technology develops, the lines between the recording studio and live performance change and become more blurred. New models for performance emerge. In a 2010 live performance given by Grammy Award winning artist Imogen Heap in New York, the artist undertakes a live, improvised construction of a piece as a performative act. She invites the audience to choose the key for the track and proceeds to layer up the various parts in front of the audience as a live performance act. Her recording process is thus revealed on stage in real time and she performs a process that what would have once been confined to the recording studio. So how do artists bring studio production processes into the live context? What aspects of studio production are now performable and what consistent models can be identified amongst the various approaches now seen? This paper will present an overview of approaches to performative realisations of studio produced tracks and will illuminate some emerging relationships between recorded music and performance across a range of contexts.

Experience design and interactive software in music education research

This paper examines the integration of computing technologies into music education research in a way informed by constructivism. In particular, this paper focuses on an approach established by Jeanne Bamberger, which the author also employs, that integrates software design, pedagogical exploration, and the building of music education theory. In this tradition, researchers design software and associated activities to facilitate the interactive manipulation of musical structures and ideas. In short, this approach focuses on designing experiences and tools that support musical thinking and doing. In comparing the work of Jean Bamberger with that of the author, this paper highlights and discusses issues of significance and identifies lessons for future research.

Sound thinking : tips and tools for understanding popular music

Sound Thinking provides techniques and approaches to critically listen, think, talk and write about music you hear or make. It provides tips on making music and it encourages regular and deep thinking about music activities, which helps build a musical dialog that leads to deeper understanding.

A superdirective 3-element array for adaptive beamforming

A small array composed of three monopole elements with very small element spacing on the order of λ/6 to λ/20 is considered for application in adaptive beamforming. The properties of this 3-port array are governed by strong mutual coupling. It is shown that for signal-to-noise maximization, it is not sufficient to adjust the weights to compensate for the effects of mutual coupling. The necessity for a RF-decoupling network (RF-DN) and its simple realization are shown. The array with closely spaced elements together with the RF-DN represents a superdirective antenna with a directivity of more than 10 dBi. It is shown that the required fractional frequency bandwidth and the available unloaded Q of the antenna and RF-DN structure determine the lower limit for the element spacing.

Governing a copyright culture in post-WTO China : copyright in the film and music industries, 2001 - 2005

In 2001 China amended its copyright law in accordance with the requirements of the Agreement on Trade Related Aspects of Intellectual Property (TRIPS). This thesis explores the impact of copyright reform on China’s domestic film and music industries. Through extensive interviews with film and music industry workers – directors, producers, executives, judges, lawyers and musicians – it investigates the role of copyright in film and music’s shift from state driven to commercially focussed. The construction and negotiation of a new ‘copyright culture’ in China is examined through the lens of Yurchak’s (1999) concept of ‘entrepreneurial governmentality.’ Administrative structures put in place prior to China’s economic reform are no longer capable of controlling film and music production and consumption and new approaches to managing it are becoming more important. High levels of unauthorised distribution are forcing these industries to adapt their business models so that they can function in a system with weak copyright protection. Legal, economic and political changes have resulted in the emergence of an ‘entrepreneurial governmentality’ among film and music industry professionals. This commercially focussed group is, in turn, increasing pressure on the state to expand the space in which it can function and support efforts to strengthen the copyright system that allows it to exist. It is suggested that the construction and negotiation of a new ‘copyright culture’ is now taking place. This thesis describes the current situation in the film and music industries. It examines the tension between the theoretical possibilities created by copyright law, and the practical challenges of operating in China. It observes innovative business models being applied by film and music businesses in China. It discusses the impact of traditional attitudes to copying and also examines the role that open licensing models might play in helping limit the negative effects of copyright protection on public access to content and in raising levels of education about copyright among key groups within the community.

Infrastructure transitions toward sustainability : a complex adaptive systems perspective

To ensure infrastructure assets are procured and maintained by government on behalf of citizens, appropriate policy and institutional architecture is needed, particularly if a fundamental shift to more sustainable infrastructure is the goal. The shift in recent years from competitive and resource-intensive procurement to more collaborative and sustainable approaches to infrastructure governance is considered a major transition in infrastructure procurement systems. In order to better understand this transition in infrastructure procurement arrangements, the concept of emergence from Complex Adaptive Systems (CAS) theory is offered as a key construct. Emergence holds that micro interactions can result in emergent macro order. Applying the concept of emergence to infrastructure procurement, this research examines how interaction of agents in individual projects can result in different industry structural characteristics. The paper concludes that CAS theory, and particularly the concept of ‘emergence’, provides a useful construct to understand infrastructure procurement dynamics and progress towards sustainability.

Regulating coal seam gas in Queensland : lessons in an adaptive environmental management approach?

The current regulatory approach to coal seam gas projects in Queensland is based on the philosophy of adaptive environmental management. This method of “learning by doing” is implemented in Queensland primarily through the imposition of layered monitoring and reporting duties on the coal seam gas operator alongside obligations to compensate and “make good” harm caused. The purpose of this article is to provide a critical review of the Queensland regulatory approach to the approval and minimisation of adverse impacts from coal seam gas activities. Following an overview of the hallmarks of an effective adaptive management approach, this article begins by addressing the mosaic of approval processes and impact assessment regimes that may apply to coal seam gas projects. This includes recent Strategic Cropping Land reforms. This article then turns to consider the preconditions for land access in Queensland and the emerging issues for landholders relating to the negotiation of access and compensation agreements. This article then undertakes a critical review of the environmental duties imposed on coal seam gas operators relating to hydraulic fracturing, well head leaks, groundwater management and the disposal and beneficial use of produced water. Finally, conclusions are drawn regarding the overall effectiveness of the Queensland framework and the lessons that may be drawn from Queensland’s adaptive environmental management approach.

Adaptive bilateral filtering using saliency map for deblocking low bit rate videos

This paper proposes a novel approach to video deblocking which performs perceptually adaptive bilateral filtering by considering color, intensity, and motion features in a holistic manner. The method is based on bilateral filter which is an effective smoothing filter that preserves edges. The bilateral filter parameters are adaptive and avoid over-blurring of texture regions and at the same time eliminate blocking artefacts in the smooth region and areas of slow motion content. This is achieved by using a saliency map to control the strength of the filter for each individual point in the image based on its perceptual importance. The experimental results demonstrate that the proposed algorithm is effective in deblocking highly compressed video sequences and to avoid over-blurring of edges and textures in salient regions of image.

Improvisation in interactive music systems

This project investigates machine listening and improvisation in interactive music systems with the goal of improvising musically appropriate accompaniment to an audio stream in real-time. The input audio may be from a live musical ensemble, or playback of a recording for use by a DJ. I present a collection of robust techniques for machine listening in the context of Western popular dance music genres, and strategies of improvisation to allow for intuitive and musically salient interaction in live performance. The findings are embodied in a computational agent – the Jambot – capable of real-time musical improvisation in an ensemble setting. Conceptually the agent’s functionality is split into three domains: reception, analysis and generation. The project has resulted in novel techniques for addressing a range of issues in each of these domains. In the reception domain I present a novel suite of onset detection algorithms for real-time detection and classification of percussive onsets. This suite achieves reasonable discrimination between the kick, snare and hi-hat attacks of a standard drum-kit, with sufficiently low-latency to allow perceptually simultaneous triggering of accompaniment notes. The onset detection algorithms are designed to operate in the context of complex polyphonic audio. In the analysis domain I present novel beat-tracking and metre-induction algorithms that operate in real-time and are responsive to change in a live setting. I also present a novel analytic model of rhythm, based on musically salient features. This model informs the generation process, affording intuitive parametric control and allowing for the creation of a broad range of interesting rhythms. In the generation domain I present a novel improvisatory architecture drawing on theories of music perception, which provides a mechanism for the real-time generation of complementary accompaniment in an ensemble setting. All of these innovations have been combined into a computational agent – the Jambot, which is capable of producing improvised percussive musical accompaniment to an audio stream in real-time. I situate the architectural philosophy of the Jambot within contemporary debate regarding the nature of cognition and artificial intelligence, and argue for an approach to algorithmic improvisation that privileges the minimisation of cognitive dissonance in human-computer interaction. This thesis contains extensive written discussions of the Jambot and its component algorithms, along with some comparative analyses of aspects of its operation and aesthetic evaluations of its output. The accompanying CD contains the Jambot software, along with video documentation of experiments and performances conducted during the project.

Re-engaging marginalized youth through digital music production: performance, audience and evaluation

This paper presents two case studies of marginalised youth experimenting with digital music production in flexible education settings. The cases were drawn from a three-year study of alternative assessment in flexible learning centres that enrol 650+ students who have left formal schooling in Queensland, Australia. The cases are framed in reference to the literature on cultural studies approaches to education and the digital arts. Each case describes the student’s histories, cultural background and experiences, music productions, evidence of learning and re-engagement with education. Findings document how digital music production can re-engage and extend participation among students who have left formal education. They do so by theorising the online judgements and blog comments about the digital music production as a social field of exchange. It also raises critical questions about the adequacy of current approaches to evaluating and accounting for the learning and development of such youth, especially where this has occurred through creative arts and digital production.

Sequential fusion of decisions from adaptive and random samples for controlled verification of errors

Fusion techniques have received considerable attention for achieving performance improvement with biometrics. While a multi-sample fusion architecture reduces false rejects, it also increases false accepts. This impact on performance also depends on the nature of subsequent attempts, i.e., random or adaptive. Expressions for error rates are presented and experimentally evaluated in this work by considering the multi-sample fusion architecture for text-dependent speaker verification using HMM based digit dependent speaker models. Analysis incorporating correlation modeling demonstrates that the use of adaptive samples improves overall fusion performance compared to randomly repeated samples. For a text dependent speaker verification system using digit strings, sequential decision fusion of seven instances with three random samples is shown to reduce the overall error of the verification system by 26% which can be further reduced by 6% for adaptive samples. This analysis novel in its treatment of random and adaptive multiple presentations within a sequential fused decision architecture, is also applicable to other biometric modalities such as finger prints and handwriting samples.