953 resultados para EXPONENTIALLY EXPANDING MESH


Relevância:

10.00% 10.00%

Publicador:

Resumo:

While substantial research on intelligent transportation systems has focused on the development of novel wireless communication technologies and protocols, relatively little work has sought to fully exploit proximity-based wireless technologies that passengers actually carry with them today. This paper presents the real-world deployment of a system that exploits public transit bus passengers’ Bluetooth-capable devices to capture and reconstruct micro- and macro-passenger behavior. We present supporting evidence that approximately 12% of passengers already carry Bluetooth-enabled devices and that the data collected on these passengers captures with almost 80 % accuracy the daily fluctuation of actual passengers flows. The paper makes three contributions in terms of understanding passenger behavior: We verify that the length of passenger trips is exponentially bounded, the frequency of passenger trips follows a power law distribution, and the microstructure of the network of passenger movements is polycentric.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background: In response to health workforce shortages policymakers have considered expanding the roles that a health professional may perform. A more traditional combination of health professional roles is that of a dispensing doctor (DD) who routinely prescribes and dispenses pharmaceuticals. A systematic review conducted on mainly overseas DDs’ practices found that DDs tended to prescribe more items per patients, less often generically, and showed poorer adherence to best practice. Convenience for patients was cited by both patients and DDs as the main reason for dispensing. In Australia, rural doctors are allowed to dispense Pharmaceutical Benefit Scheme (PBS) subsidised pharmaceutical benefits if there is no reasonable pharmacy coverage. Little was known about the practices of these Australian DDs. Objectives: To examine the PBS prescribing patterns of dispensing with matched non-dispensing doctors and identify factors that influence prescribing behaviour. Method: A sequential explanatory (QUAN-->qual) mixed methodology was utilised. Firstly, rurality-matched DDs’ and non-DDs’ PBS data for fiscal years 2005-7 were analysed against criteria distilled from a systematic review and stakeholder consultations. Secondly, structured interviews were conducted with a purposive sample of DDs to examine the quantitative findings. Key findings: DDs prescribed significantly fewer PBS prescriptions per patients but used Regulation 24 significantly more than non-DDs. Regulation 24 biased the prescribing data. DDs prescribed proportionally more penicillin type antibiotics, adrenergic inhalants and non-steroidal anti-inflammatories as compared to non-DDs. Reasons offered by DD-respondents highlighted that prescribing was influenced by an awareness of cost to the patients, peer pressure and confidential prescriber feedback provided on a regular basis. Implications: This innovative census study does not support international data that DDs are less judicious in their prescribing. There is some evidence that DDs might reduce health inequity between rural and urban Australian, and that the DD health model is valuable to patients in isolated communities.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Mobile devices and smartphones have become a significant communication channel for everyday life. The sensing capabilities of mobile devices are expanding rapidly, and sensors embedded in these devices are cheaper and more powerful than before. It is evident that mobile devices have become the most suitable candidates to sense contextual information without needing extra tools. However, current research shows only a limited number of sensors are being explored and investigated. As a result, it still needs to be clarified what forms of contextual information extracted from mo- bile sensors are useful. Therefore, this research investigates the context sensing using current mobile sensors, the study follows experimental methods and sensor data is evaluated and synthesised, in order to deduce the value of various sensors and combinations of sensor for the use in context-aware mobile applications. This study aims to develop a context fusion framework that will enhance the context-awareness on mobile applications, as well as exploring innovative techniques for context sensing on smartphone devices.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Emotions play a significant role in people’s lives, including interactions with portable devices. The research aimed to understand the evolving emotional experience between people and portable interactive devices (PIDs). Activity Theory was the theoretical framework used to contextualise the research approach and findings. Two longitudinal experiments were conducted investigating emotional experiences with PIDs over six months. Experiment 1 focused on media / entertainment PIDs while Experiment 2 focused on medical / health PIDs. Mixed research methods consisting of diaries, interviews and codiscovery sessions were used to collect data. Results identified that more social interactions were experienced with media PIDs than medical PIDs. Different Task Categories, and their emotional responses, were also revealed including Features, Functional, Mediation and Auxiliary Categories. Functional and Mediation categories were characterised as overall positive while Features and Auxiliary Categories were characterised as overall negative. Further, the consequences of Negative Personal and Social interactions on the overall emotional experience were determined. For media PIDs, Negative Social experiences adversely impacted the evolving emotional experience. For medical PIDs, both Negative Social and Negative Personal experiences adversely impacted the evolving emotional experience. As a result of the findings the Designing for Evolving Emotional Experience framework was developed, outlining principles to promote positive, and avoid negative, emotional experiences with PIDs. Contributions to knowledge from the research include methodological contributions, advancing understanding of emotional experiences with PIDs, expanding the taxonomy of emotional interactions with PIDs and broadening emotion design theory and principles. The thesis concludes with an outline of implications to design research, design and related fields, future research potentials, as well as the positive contributions to designing for meaningful and enjoyable experiences in everyday life.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The ability of a piezoelectric transducer in energy conversion is rapidly expanding in several applications. Some of the industrial applications for which a high power ultrasound transducer can be used are surface cleaning, water treatment, plastic welding and food sterilization. Also, a high power ultrasound transducer plays a great role in biomedical applications such as diagnostic and therapeutic applications. An ultrasound transducer is usually applied to convert electrical energy to mechanical energy and vice versa. In some high power ultrasound system, ultrasound transducers are applied as a transmitter, as a receiver or both. As a transmitter, it converts electrical energy to mechanical energy while a receiver converts mechanical energy to electrical energy as a sensor for control system. Once a piezoelectric transducer is excited by electrical signal, piezoelectric material starts to vibrate and generates ultrasound waves. A portion of the ultrasound waves which passes through the medium will be sensed by the receiver and converted to electrical energy. To drive an ultrasound transducer, an excitation signal should be properly designed otherwise undesired signal (low quality) can deteriorate the performance of the transducer (energy conversion) and increase power consumption in the system. For instance, some portion of generated power may be delivered in unwanted frequency which is not acceptable for some applications especially for biomedical applications. To achieve better performance of the transducer, along with the quality of the excitation signal, the characteristics of the high power ultrasound transducer should be taken into consideration as well. In this regard, several simulation and experimental tests are carried out in this research to model high power ultrasound transducers and systems. During these experiments, high power ultrasound transducers are excited by several excitation signals with different amplitudes and frequencies, using a network analyser, a signal generator, a high power amplifier and a multilevel converter. Also, to analyse the behaviour of the ultrasound system, the voltage ratio of the system is measured in different tests. The voltage across transmitter is measured as an input voltage then divided by the output voltage which is measured across receiver. The results of the transducer characteristics and the ultrasound system behaviour are discussed in chapter 4 and 5 of this thesis. Each piezoelectric transducer has several resonance frequencies in which its impedance has lower magnitude as compared to non-resonance frequencies. Among these resonance frequencies, just at one of those frequencies, the magnitude of the impedance is minimum. This resonance frequency is known as the main resonance frequency of the transducer. To attain higher efficiency and deliver more power to the ultrasound system, the transducer is usually excited at the main resonance frequency. Therefore, it is important to find out this frequency and other resonance frequencies. Hereof, a frequency detection method is proposed in this research which is discussed in chapter 2. An extended electrical model of the ultrasound transducer with multiple resonance frequencies consists of several RLC legs in parallel with a capacitor. Each RLC leg represents one of the resonance frequencies of the ultrasound transducer. At resonance frequency the inductor reactance and capacitor reactance cancel out each other and the resistor of this leg represents power conversion of the system at that frequency. This concept is shown in simulation and test results presented in chapter 4. To excite a high power ultrasound transducer, a high power signal is required. Multilevel converters are usually applied to generate a high power signal but the drawback of this signal is low quality in comparison with a sinusoidal signal. In some applications like ultrasound, it is extensively important to generate a high quality signal. Several control and modulation techniques are introduced in different papers to control the output voltage of the multilevel converters. One of those techniques is harmonic elimination technique. In this technique, switching angles are chosen in such way to reduce harmonic contents in the output side. It is undeniable that increasing the number of the switching angles results in more harmonic reduction. But to have more switching angles, more output voltage levels are required which increase the number of components and cost of the converter. To improve the quality of the output voltage signal with no more components, a new harmonic elimination technique is proposed in this research. Based on this new technique, more variables (DC voltage levels and switching angles) are chosen to eliminate more low order harmonics compared to conventional harmonic elimination techniques. In conventional harmonic elimination method, DC voltage levels are same and only switching angles are calculated to eliminate harmonics. Therefore, the number of eliminated harmonic is limited by the number of switching cycles. In the proposed modulation technique, the switching angles and the DC voltage levels are calculated off-line to eliminate more harmonics. Therefore, the DC voltage levels are not equal and should be regulated. To achieve this aim, a DC/DC converter is applied to adjust the DC link voltages with several capacitors. The effect of the new harmonic elimination technique on the output quality of several single phase multilevel converters is explained in chapter 3 and 6 of this thesis. According to the electrical model of high power ultrasound transducer, this device can be modelled as parallel combinations of RLC legs with a main capacitor. The impedance diagram of the transducer in frequency domain shows it has capacitive characteristics in almost all frequencies. Therefore, using a voltage source converter to drive a high power ultrasound transducer can create significant leakage current through the transducer. It happens due to significant voltage stress (dv/dt) across the transducer. To remedy this problem, LC filters are applied in some applications. For some applications such as ultrasound, using a LC filter can deteriorate the performance of the transducer by changing its characteristics and displacing the resonance frequency of the transducer. For such a case a current source converter could be a suitable choice to overcome this problem. In this regard, a current source converter is implemented and applied to excite the high power ultrasound transducer. To control the output current and voltage, a hysteresis control and unipolar modulation are used respectively. The results of this test are explained in chapter 7.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Classifier selection is a problem encountered by multi-biometric systems that aim to improve performance through fusion of decisions. A particular decision fusion architecture that combines multiple instances (n classifiers) and multiple samples (m attempts at each classifier) has been proposed in previous work to achieve controlled trade-off between false alarms and false rejects. Although analysis on text-dependent speaker verification has demonstrated better performance for fusion of decisions with favourable dependence compared to statistically independent decisions, the performance is not always optimal. Given a pool of instances, best performance with this architecture is obtained for certain combination of instances. Heuristic rules and diversity measures have been commonly used for classifier selection but it is shown that optimal performance is achieved for the `best combination performance' rule. As the search complexity for this rule increases exponentially with the addition of classifiers, a measure - the sequential error ratio (SER) - is proposed in this work that is specifically adapted to the characteristics of sequential fusion architecture. The proposed measure can be used to select a classifier that is most likely to produce a correct decision at each stage. Error rates for fusion of text-dependent HMM based speaker models using SER are compared with other classifier selection methodologies. SER is shown to achieve near optimal performance for sequential fusion of multiple instances with or without the use of multiple samples. The methodology applies to multiple speech utterances for telephone or internet based access control and to other systems such as multiple finger print and multiple handwriting sample based identity verification systems.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The recognition and enforcement of foreign judgments is an aspect of private international law, and concerns situations where a successful party to litigation seeks to rely on a judgment obtained in one court, in a court in another jurisdiction. The most common example where the recognition and enforcement of foreign judgments may arise is where a party who has obtained a favourable judgment in one state or country may seek to recognise and enforce the judgment in another state or country. This occurs because there is no sufficient asset in the state or country where the judgment was rendered to satisfy that judgment. As technological advancements in communications over vast geographical distances have improved exponentially in recent years, there has been an increase in cross-border transactions, as well as litigation arising from these transactions. As a result, the recognition and enforcement of foreign judgments is of increasing importance, since a party who has obtained a judgment in cross-border litigation may wish to recognise and enforce the judgment in another state or country, where the defendant’s assets may be located without having to re-litigate substantive issues that have already been resolved in another court. The purpose of the study is to examine whether the current state of laws for the recognition and enforcement of foreign judgments in Australia, the United States and the European Community are in line with modern-commercial needs. The study is conducted by weighing two competing objectives between the notion of finality of litigation, which encourages courts to recognise and enforce judgments foreign to them, on the one hand, and the adequacy of protection to safeguard the recognition and enforcement proceedings, so that there would be no injustice or unfairness if a foreign judgment is recognised and enforced, on the other. The findings of the study are as follows. In both Australia and the United States, there is a different approach concerning the recognition and enforcement of judgments rendered by courts interstate or in a foreign country. In order to maintain a single and integrated nation, there are constitutional and legislative requirements authorising courts to give conclusive effects to interstate judgments. In contrast, if the recognition and enforcement actions involve judgments rendered by a foreign country’s court, an Australian or a United States court will not recognise and enforce the foreign judgment unless the judgment has satisfied a number of requirements and does not fall under any of the exceptions to justify its non-recognition and non-enforcement. In the European Community, the Brussels I Regulation which governs the recognition and enforcement of judgments among European Union Member States has created a scheme, whereby there is only a minimal requirement that needs to be satisfied for the purposes of recognition and enforcement. Moreover, a judgment that is rendered by a Member State and based on any of the jurisdictional bases set forth in the Brussels I Regulation is entitled to be recognised and enforced in another Member State without further review of its underlying jurisdictional basis. However, there are concerns as to the adequacy of protection available under the Brussels I Regulation to safeguard the judgment-enforcing Member States, as well as those against whom recognition or enforcement is sought. This dissertation concludes by making two recommendations aimed at improving the means by which foreign judgments are recognised and enforced in the selected jurisdictions. The first is for the law in both Australia and the United States to undergo reform, including: adopting the real and substantial connection test as the new jurisdictional basis for the purposes of recognition and enforcement; liberalising the existing defences to safeguard the application of the real and substantial connection test; extending the application of the Foreign Judgments Act 1991 (Cth) in Australia to include at least its important trading partners; and implementing a federal statutory scheme in the United States to govern the recognition and enforcement of foreign judgments. The second recommendation is to introduce a convention on jurisdiction and the recognition and enforcement of foreign judgments. The convention will be a convention double, which provides uniform standards for the rules of jurisdiction a court in a contracting state must exercise when rendering a judgment and a set of provisions for the recognition and enforcement of resulting judgments.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In recent years, with the impact of global knowledge economy, a more comprehensive development approach has gained significant popularity. This new development approach, so called ‘knowledge-based urban development’, is different from its traditional predecessor. With a much more balanced focus on all of the four key development domains – economic, spatial, institutional, and socio-cultural – this contemporary approach, aims to bring economic prosperity, environmental sustainability and local institutional competence with a just socio-spatial order to our cities and regions. The ultimate goal of knowledgebased urban development is to produce a city purposefully designed to encourage the continuous production, circulation and commercialization of social and scientific knowledge – this will in turn establish a ‘knowledge city’. A city following the ‘knowledge city’ concept embarks on a strategic mission to firmly encourage and nurture locally focused innovation, science and creativity within the context of an expanding knowledge economy and society. In this regard a ‘knowledge city’ can be seen as an integrated city, which physically and institutionally combines the functions of a science and technology park with civic and residential functions and urban amenities. It also offers one of the effective paradigms for the sustainable cities of our time. This sixth edition of KCWS – The 6th Knowledge Cities World Summit 2013 – makes an important reminder that the ‘knowledge city’ concept is a key notion in the 21st Century development. Considering this notion, the Summit sheds light on the multifaceted dimensions and various scales of building a ‘knowledge city’ via ‘knowledge-based urban development’ paradigm by particularly focusing on the overall Summit theme of ‘Establishing Bridges’. At this summit, the theoretical and practical maturing of knowledge-based development paradigms are advanced through the interplay between the world’s leading academics’ theories and the practical models and strategies of practitioners’ and policy makers’ drawn from around the world. This summit proceeding is compiled in order to disseminate the knowledge generated and shared in KCWS 2013 with the wider research, governance, and practice communities the knowledge co-created in this summit. All papers of this proceeding have gone through a double-blind peer review process and been reviewed by our summit editorial review and advisory board members. We, organizers of the summit, cordially thank the members of the Summit Proceeding Editorial Review and Advisory Board for their diligent work in the review of the papers. Also we thank Prof.Dr. Ahmet Ademoğlu, Rector of İstanbul Şehir University, for providing all the support for the Summit. We hope the papers in this proceeding will inspire and make a significant contribution to the research, governance, and practice circles.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Tag recommendation is a specific recommendation task for recommending metadata (tag) for a web resource (item) during user annotation process. In this context, sparsity problem refers to situation where tags need to be produced for items with few annotations or for user who tags few items. Most of the state of the art approaches in tag recommendation are rarely evaluated or perform poorly under this situation. This paper presents a combined method for mitigating sparsity problem in tag recommendation by mainly expanding and ranking candidate tags based on similar items’ tags and existing tag ontology. We evaluated the approach on two public social bookmarking datasets. The experiment results show better accuracy for recommendation in sparsity situation over several state of the art methods.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

While Conceptual fashion design practices have been a pervasive influence in fashion since the early 1980s, there is little academic analysis that might explain how they are distinct from conventional fashion design practices. In addition, fashion practitioners have not historically contributed to fashion research. As a result, contemporary fashion practitioners have difficulty setting critical contexts and expanding their creative work as there is little relevant literature available from practitioner perspectives. This project uses practice-led research to develop a discourse for understanding Conceptual fashion design process and how it relates to more conventional fashion design practices. In this exegesis I use Conceptual art as a lens to expand understandings of Conceptual fashion and my own creative practice. This analysis demonstrates that there are valuable connections to be drawn between Conceptual art and Conceptual fashion practice. In particular, these connections reveal the differences between the way Conceptual and more conventional fashion designers relate to the conceptual and the visual in their design process. This exploration demonstrates that while fashion is a visual field, Conceptual fashion designers produce a more ‘intellectual’ type of fashion that uses the visual to communicate ideas that question the nature of fashion. I explore the relevance of these ideas through application and experimentation in my creative practice projects by drawing from systems and rules identified in the work of early Conceptual artists and contemporary Conceptual fashion designers.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This paper details the participation of the Australian e- Health Research Centre (AEHRC) in the ShARe/CLEF 2013 eHealth Evaluation Lab { Task 3. This task aims to evaluate the use of information retrieval (IR) systems to aid consumers (e.g. patients and their relatives) in seeking health advice on the Web. Our submissions to the ShARe/CLEF challenge are based on language models generated from the web corpus provided by the organisers. Our baseline system is a standard Dirichlet smoothed language model. We enhance the baseline by identifying and correcting spelling mistakes in queries, as well as expanding acronyms using AEHRC's Medtex medical text analysis platform. We then consider the readability and the authoritativeness of web pages to further enhance the quality of the document ranking. Measures of readability are integrated in the language models used for retrieval via prior probabilities. Prior probabilities are also used to encode authoritativeness information derived from a list of top-100 consumer health websites. Empirical results show that correcting spelling mistakes and expanding acronyms found in queries signi cantly improves the e ectiveness of the language model baseline. Readability priors seem to increase retrieval e ectiveness for graded relevance at early ranks (nDCG@5, but not precision), but no improvements are found at later ranks and when considering binary relevance. The authoritativeness prior does not appear to provide retrieval gains over the baseline: this is likely to be because of the small overlap between websites in the corpus and those in the top-100 consumer-health websites we acquired.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Mathematical models of mosquito-borne pathogen transmission originated in the early twentieth century to provide insights into how to most effectively combat malaria. The foundations of the Ross–Macdonald theory were established by 1970. Since then, there has been a growing interest in reducing the public health burden of mosquito-borne pathogens and an expanding use of models to guide their control. To assess how theory has changed to confront evolving public health challenges, we compiled a bibliography of 325 publications from 1970 through 2010 that included at least one mathematical model of mosquito-borne pathogen transmission and then used a 79-part questionnaire to classify each of 388 associated models according to its biological assumptions. As a composite measure to interpret the multidimensional results of our survey, we assigned a numerical value to each model that measured its similarity to 15 core assumptions of the Ross–Macdonald model. Although the analysis illustrated a growing acknowledgement of geographical, ecological and epidemiological complexities in modelling transmission, most models during the past 40 years closely resemble the Ross–Macdonald model. Modern theory would benefit from an expansion around the concepts of heterogeneous mosquito biting, poorly mixed mosquito-host encounters, spatial heterogeneity and temporal variation in the transmission process.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The preferential invasion of particular red blood cell (RBC) age classes may offer a mechanism by which certain species of Plasmodia regulate their population growth. Asexual reproduction of the parasite within RBCs exponentially increases the number of circulating parasites; limiting this explosion in parasite density may be key to providing sufficient time for the parasite to reproduce, and for the host to develop a specific immune response. It is critical that the role of preferential invasion in infection is properly understood to model the within-host dynamics of different Plasmodia species. We develop a simulation model to show that limiting the range of RBC age classes available for invasion is a credible mechanism for restricting parasite density, one which is equally as important as the maximum parasite replication rate and the duration of the erythrocytic cycle. Different species of Plasmodia that regularly infect humans exhibit different preferences for RBC invasion, with all species except P. falciparum appearing to exhibit a combination of characteristics which are able to selfregulate parasite density.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Geographical market expansion is included in various definitions of entrepreneurship as it entails the opening up of new markets (for example, Davidsson 2003). Expansion into new international markets and launch of new products in international markets are also consistent with definitions of entrepreneurship which center on the pursuit of opportunities {e.g.\Stevenson, 1983 #922;Gartner, 1993 #931}. Accordingly, the decision by managers of small, internationally active businesses to continue to internationalize can be viewed as an entrepreneurial act. In spite of the fact that both start-ups and existing firms can behave entrepreneurially by expanding into new international markets, the attention of entrepreneurship researchers interested in international activities has largely focused on international new ventures (INVs); that is, business organizations that internationalize from inception (Oviatt, and McDougall 1994; Oviatt, and McDougall 1997). Consequently, pursuit of international opportunities by established small and medium-sized enterprises (SMEs) lacks theoretical understanding and empirical investigation through an entrepreneurship lens. This paper contributes to the body of knowledge at the entrepreneurship-internationalization interface by testing whether Stevenson’s opportunity-based conceptualization of entrepreneurial management (Stevenson 1983; Stevenson and Gumpert 1985; Stevenson and Jarillo 1990) can explain the attainment of continued entrepreneurial outcomes by SMEs operating in foreign markets. We choose Stevenson’s conceptualization as it gauges firm-level characteristics that are theorized to facilitate the pursuit of entrepreneurial opportunities, which arguably is at the heart of SMEs’ continued venturing into international markets.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Current approaches to airport development and land use sit at odds with the tradition of airports as spaces for aviation (Stevens et a/. 2010). While airports remain the primary interface between air transport and society, the functions they include within their boundaries have expanded well beyond the provision of infrastructure for aviation and logistics. Shopping malls, commercial office space, hotels, golf courses and conference facilities arc increasingly normal uses of land within airport boundaries (Kasarda 2008), and enhance the role of airports from transport infrastructure to a new form of economic infrastructure (Freestone 2009). However, the expanding role of airports, and the resulting diversification in airport land uses, has not been without opposition.