Age model for the time between 3.45 and 2.45 Ma of ODP Site 189-1172

Calcareous nannoplankton assemblages and benthic d18O isotopes of Pliocene deep-sea sediments of ODP site 1172 (East of Tasmania) have been studied to improve our knowledge of the Southern Ocean paleoceanography. Our study site is located just north of the Subtropical Front (STF), an ideal setting to monitor migrations of the STF during our study period, between 3.45 and 2.45 Ma. The assemblage identified at ODP site 1172 has been interpreted as characteristic for the transitional zone water mass, located south of the STF, based on: (i) the low abundances (< 1%) of subtropical taxa, (ii) relatively high percentages of Coccolithus pelagicus, a subpolar type species, (iii) abundances from 2-10% of Calcidiscus leptoporus, a species that frequently inhabits the zone south of the STF and (iv) the high abundances of small Noelaerhabdaceae which at present dominates the zone south of the STF. Across our interval the calcareous nannoplankton manifests glacial-interglacial variability. We have identified cold events, characterized by high abundances of C. pelagicus which coincide with glacial periods, except during G7. After 3.1 Ma cold events are more frequent, in concordance with global cooling trends. Around 2.75 Ma, the interglacial stage G7 is characterized by anomalous low temperatures which most likely are linked to definite closure of the Central American Seaway (CAS), an event that is believed to have had global consequences. A gradual increase of very small Reticulofenestra across our section marks a significant trend in the small Noelaerhabdaceae species group and has been linked to a general enhanced mixing of the water column in agreement with previous studies. It is suggested that a rapid decline of small Gephyrocapsa after isotopic stage G7 might be related to the cooling observed in our study site after the closure of the CAS.

Real-time image processing for crop/weed discrimination in maize fields

This paper presents a computer vision system that successfully discriminates between weed patches and crop rows under uncontrolled lighting in real-time. The system consists of two independent subsystems, a fast image processing delivering results in real-time (Fast Image Processing, FIP), and a slower and more accurate processing (Robust Crop Row Detection, RCRD) that is used to correct the first subsystem's mistakes. This combination produces a system that achieves very good results under a wide variety of conditions. Tested on several maize videos taken of different fields and during different years, the system successfully detects an average of 95% of weeds and 80% of crops under different illumination, soil humidity and weed/crop growth conditions. Moreover, the system has been shown to produce acceptable results even under very difficult conditions, such as in the presence of dramatic sowing errors or abrupt camera movements. The computer vision system has been developed for integration into a treatment system because the ideal setup for any weed sprayer system would include a tool that could provide information on the weeds and crops present at each point in real-time, while the tractor mounting the spraying bar is moving

IDRA (IDeal Resource Allocation): Computing ideal speedups in parallel logic programming

We present a technique to estimate accurate speedups for parallel logic programs with relative independence from characteristics of a given implementation or underlying parallel hardware. The proposed technique is based on gathering accurate data describing one execution at run-time, which is fed to a simulator. Alternative schedulings are then simulated and estimates computed for the corresponding speedups. A tool implementing the aforementioned techniques is presented, and its predictions are compared to the performance of real systems, showing good correlation.

Night time performance of a storage integrated solar thermophotovoltaic (SISTPV) system

Energy storage at low maintenance cost is one of the key challenges for generating electricity from the solar energy. This paper presents the theoretical analysis (verified by CFD) of the night time performance of a recently proposed conceptual system that integrates thermal storage (via phase change materials) and thermophotovoltaics for power generation. These storage integrated solar thermophotovoltaic (SISTPV) systems are attractive owing to their simple design (no moving parts) and modularity compared to conventional Concentrated Solar Power (CSP) technologies. Importantly, the ability of high temperature operation of these systems allows the use of silicon (melting point of 1680 K) as the phase change material (PCM). Silicon's very high latent heat of fusion of 1800 kJ/kg and low cost ($1.70/kg), makes it an ideal heat storage medium enabling for an extremely high storage energy density and low weight modular systems. In this paper, the night time operation of the SISTPV system optimised for steady state is analysed. The results indicate that for any given PCM length, a combination of small taper ratio and large inlet hole-to-absorber area ratio are essential to increase the operation time and the average power produced during the night time. Additionally, the overall results show that there is a trade-off between running time and the average power produced during the night time. Average night time power densities as high as 30 W/cm(2) are possible if the system is designed with a small PCM length (10 cm) to operate just a few hours after sun-set, but running times longer than 72 h (3 days) are possible for larger lengths (50 cm) at the expense of a lower average power density of about 14 W/cm(2). In both cases the steady state system efficiency has been predicted to be about 30%. This makes SISTPV systems to be a versatile solution that can be adapted for operation in a broad range of locations with different climate conditions, even being used off-grid and in space applications.

3D teaching: the ideal complement for professionals in design and construction

Today, the requirement of professional skills to university students is constantly increasing in our society. In our opinion, the content offered in official degrees need to be nourished with different variables, enriching their global professional knowledge in a parallel way; that is why, in recent years, there is a great multiplicity of complementary courses at university. One of the most socially demanded technical requirements within the architectural, design or engineering field is the management of 3D drawing software, becoming an indispensable reality in these sectors. Thus, this specific training becomes essential over two-dimension traditional design, because the inclusion of great possibilities of spatial development that go beyond conventional orthographic projections (plans, sections or elevations), allowing modelling and rotation of the selected items from multiple angles and perspectives. Therefore, this paper analyzes the teaching methodology of a complementary course for those technicians in the construction industry interested in computer-aided design, using modelling (SketchupMake) and rendering programs (Kerkythea). The course is developed from the technician point of view, by learning computer management and its application to professional development from a more general to a more specific view through practical examples. The proposed methodology is based on the development of real examples in different professional environments such as rehabilitation, new constructions, opening projects or architectural design. This multidisciplinary contribution improves criticism of students in different areas, encouraging new learning strategies and the independent development of three-dimensional solutions. Thus, the practical implementation of new situations, even suggested by the students themselves, ensures active participation, saving time during the design process and the increase of effectiveness when generating elements which may be represented, moved or virtually tested. In conclusion, this teaching-learning methodology improves the skills and competencies of students to face the growing professional demands of society. After finishing the course, technicians not only improved their expertise in the field of drawing but they also enhanced their capacity for spatial vision; both essential qualities in these sectors that can be applied to their professional development with great success.

Women, computing and the 'ideal worker': A comparison of professional occupations

In this paper we use recent census data supplemented with case study evidence to investigate the extent to which professional computing occupations in Australia are constructed around the notion of an ‘ideal’ worker. Census data are used to compare computer professionals with other selected professional occupational groups, illustrating different models of accommodating (or not accommodating) workers who do not fit the ideal model. The computer professionals group is shown to be distinctive in combining low but consistent levels of female representation across age groups, average rates of parenthood and minimal provisions for working-time flexibility. One strategy employed by women in this environment is selection of relatively routine technical roles over more time intensive consultancy based work.

Environmental scanning electron microscopy offers real-time morphological analysis of liposomes and niosomes

Liposomes have been imaged using a plethora of techniques. However, few of these methods offer the ability to study these systems in their natural hydrated state without the requirement of drying, staining, and fixation of the vesicles. However, the ability to image a liposome in its hydrated state is the ideal scenario for visualization of these dynamic lipid structures and environmental scanning electron microscopy (ESEM), with its ability to image wet systems without prior sample preparation, offers potential advantages to the above methods. In our studies, we have used ESEM to not only investigate the morphology of liposomes and niosomes but also to dynamically follow the changes in structure of lipid films and liposome suspensions as water condenses on to or evaporates from the sample. In particular, changes in liposome morphology were studied using ESEM in real time to investigate the resistance of liposomes to coalescence during dehydration thereby providing an alternative assay of liposome formulation and stability. Based on this protocol, we have also studied niosome-based systems and cationic liposome/DNA complexes. Copyright © Informa Healthcare.

Modelling data and voice traffic over IP networks using continuous-time Markov models

Common approaches to IP-traffic modelling have featured the use of stochastic models, based on the Markov property, which can be classified into black box and white box models based on the approach used for modelling traffic. White box models, are simple to understand, transparent and have a physical meaning attributed to each of the associated parameters. To exploit this key advantage, this thesis explores the use of simple classic continuous-time Markov models based on a white box approach, to model, not only the network traffic statistics but also the source behaviour with respect to the network and application. The thesis is divided into two parts: The first part focuses on the use of simple Markov and Semi-Markov traffic models, starting from the simplest two-state model moving upwards to n-state models with Poisson and non-Poisson statistics. The thesis then introduces the convenient to use, mathematically derived, Gaussian Markov models which are used to model the measured network IP traffic statistics. As one of the most significant contributions, the thesis establishes the significance of the second-order density statistics as it reveals that, in contrast to first-order density, they carry much more unique information on traffic sources and behaviour. The thesis then exploits the use of Gaussian Markov models to model these unique features and finally shows how the use of simple classic Markov models coupled with use of second-order density statistics provides an excellent tool for capturing maximum traffic detail, which in itself is the essence of good traffic modelling. The second part of the thesis, studies the ON-OFF characteristics of VoIP traffic with reference to accurate measurements of the ON and OFF periods, made from a large multi-lingual database of over 100 hours worth of VoIP call recordings. The impact of the language, prosodic structure and speech rate of the speaker on the statistics of the ON-OFF periods is analysed and relevant conclusions are presented. Finally, an ON-OFF VoIP source model with log-normal transitions is contributed as an ideal candidate to model VoIP traffic and the results of this model are compared with those of previously published work.

From ideal to real:a longitudinal study of the role of implicit leadership theories on leader-member exchanges and employee outcomes

The results of the present longitudinal study demonstrate the importance of implicit leadership theories (ILTs) for the quality of leader-member exchanges (LMX) and employees' organizational commitment, job satisfaction, and well-being. Results based on a sample of 439 employees who completed the study questionnaires at 2 time points showed that the closer employees perceived their actual manager's profile to be to the ILTs they endorsed, the better the quality of LMX. Results also indicated that the implicit-explicit leadership traits difference had indirect effects on employee attitudes and well-being. These findings were consistent across employee groups that differed in terms of job demand and the duration of manager-employee relation, but not in terms of motivation. Furthermore, crossed-lagged modeling analyses of the longitudinal data explored the possibility of reciprocal effects between implicit-explicit leadership traits difference and LMX and provided support for the initially hypothesized direction of causal effects.

[Review of] Ivo Mijnssen, The Quest for an Ideal Youth in Putin’s Russia I. Back to Our Future! History, Modernity and Patriotism According to Nashi, 2005–2012. Soviet and Post-Soviet Politics and Society, Stuttgart: Ibidem Verlag, 2012, 202pp., e 34.90 p/b

THE YOUTH MOVEMENT NASHI (OURS) WAS FOUNDED IN THE SPRING of 2005 against the backdrop of Ukraine’s ‘Orange Revolution’. Its aim was to stabilise Russia’s political system and take back the streets from opposition demonstrators. Personally loyal to Putin and taking its ideological orientation from Surkov’s concept of ‘sovereign democracy’, Nashi has sought to turn the tide on ‘defeatism’ and develop Russian youth into a patriotic new elite that ‘believes in the future of Russia’ (p. 15). Combining a wealth of empirical detail and the application of insights from discourse theory, Ivo Mijnssen analyses the organisation’s development between 2005 and 2012. His analysis focuses on three key moments—the organisation’s foundation, the apogee of its mobilisation around the Bronze Soldier dispute with Estonia, and the 2010 Seliger youth camp—to help understand Nashi’s organisation, purpose and ideational outlook as well as the limitations and challenges it faces. As such,the book is insightful both for those with an interest in post-Soviet Russian youth culture, and for scholars seeking a rounded understanding of the Kremlin’s initiatives to return a sense of identity and purpose to Russian national life.The first chapter, ‘Background and Context’, outlines the conceptual toolkit provided by Ernesto Laclau and Chantal Mouffe to help make sense of developments on the terrain of identity politics. In their terms, since the collapse of the Soviet Union, Russia has experienced acute dislocation of its identity. With the tangible loss of great power status, Russian realities have become unfixed from a discourse enabling national life to be constructed, albeit inherently contingently, as meaningful. The lack of a Gramscian hegemonic discourse to provide a unifying national idea was securitised as an existential threat demanding special measures. Accordingly, the identification of those who are ‘notUs’ has been a recurrent theme of Nashi’s discourse and activity. With the victory in World War II held up as a foundational moment, a constitutive other is found in the notion of ‘unusual fascists’. This notion includes not just neo-Nazis, but reflects a chain of equivalence that expands to include a range of perceived enemies of Putin’s consolidation project such as oligarchs and pro-Western liberals.The empirical background is provided by the second chapter, ‘Russia’s Youth, the Orange Revolution, and Nashi’, which traces the emergence of Nashi amid the climate of political instability of 2004 and 2005. A particularly note-worthy aspect of Mijnssen’s work is the inclusion of citations from his interviews with Nashicommissars; the youth movement’s cadres. Although relatively few in number, such insider conversations provide insight into the ethos of Nashi’s organisation and the outlook of those who have pledged their involvement. Besides the discussion of Nashi’s manifesto, the reader thus gains insight into the motivations of some participants and behind-the-scenes details of Nashi’s activities in response to the perceived threat of anti-government protests. The third chapter, ‘Nashi’s Bronze Soldier’, charts Nashi’s role in elevating the removal of a World War II monument from downtown Tallinn into an international dispute over the interpretation of history. The events subsequent to this securitisation of memory are charted in detail, concluding that Nashi’s activities were ultimately unsuccessful as their demands received little official support.The fourth chapter, ‘Seliger: The Foundry of Modernisation’, presents a distinctive feature of Mijnssen’s study, namely his ethnographic account as a participant observer in the Youth International Forum at Seliger. In the early years of the camp (2005–2007), Russian participants received extensive training, including master classes in ‘methods of forestalling mass unrest’ (p. 131), and the camp served to foster a sense of group identity and purpose among activists. After 2009 the event was no longer officially run as a Nashi camp, and its role became that of a forum for the exchange of ideas about innovation, although camp spirit remained a central feature. In 2010 the camp welcomed international attendees for the first time. As one of about 700 international participants in that year the author provides a fascinating account based on fieldwork diaries.Despite the polemical nature of the topic, Mijnssen’s analysis remains even-handed, exemplified in his balanced assessment of the Seliger experience. While he details the frustrations and disappointments of the international participants with regard to the unaccustomed strict camp discipline, organisational and communication failures, and the controlled format of many discussions,he does not neglect to note the camp’s successes in generating a gratifying collective dynamic between the participants, even among the international attendees who spent only a week there.In addition to the useful bibliography, the book is back-ended by two appendices, which provide the reader with important Russian-language primary source materials. The first is Nashi’s ‘Unusual Fascism’ (Neobyknovennyi fashizm) brochure, and the second is the booklet entitled ‘Some Uncomfortable Questions to the Russian Authorities’ (Neskol’ko neudobnykh voprosov rossiiskoivlasti) which was provided to the Seliger 2010 instructors to guide them in responding to probing questions from foreign participants. Given that these are not readily publicly available even now, they constitute a useful resource from the historical perspective.

A organização da educação no território federal do Amapá: do "ideal" ao real, do liberal ao conservador (1943-1958)

The present study on “organization education on Amapá’s Federal Territory (1943-1958)”, looked forward to answering the following questions: Was there an educational policy, in a systemic way, on the former Amapá’s federal territory? On the other hand, what were the main initiatives of the first intervenors for the education dissemination? After facing these questions, we established, as hypothesis, that the developed actions in the education’s scope on that territory back in the 40’s and 50’s were not able to implant an educational project in Amapá, since there was no preoccupation to understanding the sociocultural reality of Amapá’s population. Given this hypothesis, we analyzed the relation between the political practices developed by the first intervenor on the territory and the brazilian political scenario, from the legal-administrative nature of the federal entities and political conjuncture of the “New State” (1937-1945). To achieve that, we sought some similarities between Janary Gentil Nunes’s ways of governing and Getúlio Vargas’s political actions. To make this happen, it was necessary to check official documents out, as well as unofficial ones, especially the old articles published by “Amapá”, the local newspaper, official press tool back then, which disseminated the beliefs and values of the constituted authorities, with the purpose of “strengthen” the “modernization” ideal on the people. Such practice was based on the attempt of breaking off sociocultural economic backwardness of the territory, hiding out the reality of the Amapá’s population, marked by poverty, a high illiteracy rate and the typical tropical diseases from Amazon (Malaria). During the rupture’s process between the old and the modern, the education takes on a major role in the official speech, being used as political advertisement and as essential element to the modernization and to the development of a “new man”: now “civilized”. However, the investigation on the expansion of the elementary education in Amapá, showed us the presence of a significant number of rural schools, in contradiction to the disseminated urban modernization promise around there. In this sense, we can affirm that educational policy on Amapá’s territory failed by reasons of being based on the “transplantation” of the Federal District’s educational project, and it is important to recall that, back then, the brazilian Federal District was Rio de Janeiro. Despite the public agents had established uncountable schools on rural areas, these were not carried out from a more systemic process, this is, considering the reality of the Amazon’s "cabloco". So, we observed the existence of the separation between the modern speech and the maintenance of old oligarchic practices by that time.

Design and implementation of generalized topologies of time-interleaved variable bandpass Σ−Δ modulators

In this thesis, novel analog-to-digital and digital-to-analog generalized time-interleaved variable bandpass sigma-delta modulators are designed, analysed, evaluated and implemented that are suitable for high performance data conversion for a broad-spectrum of applications. These generalized time-interleaved variable bandpass sigma-delta modulators can perform noise-shaping for any centre frequency from DC to Nyquist. The proposed topologies are well-suited for Butterworth, Chebyshev, inverse-Chebyshev and elliptical filters, where designers have the flexibility of specifying the centre frequency, bandwidth as well as the passband and stopband attenuation parameters. The application of the time-interleaving approach, in combination with these bandpass loop-filters, not only overcomes the limitations that are associated with conventional and mid-band resonator-based bandpass sigma-delta modulators, but also offers an elegant means to increase the conversion bandwidth, thereby relaxing the need to use faster or higher-order sigma-delta modulators. A step-by-step design technique has been developed for the design of time-interleaved variable bandpass sigma-delta modulators. Using this technique, an assortment of lower- and higher-order single- and multi-path generalized A/D variable bandpass sigma-delta modulators were designed, evaluated and compared in terms of their signal-to-noise ratios, hardware complexity, stability, tonality and sensitivity for ideal and non-ideal topologies. Extensive behavioural-level simulations verified that one of the proposed topologies not only used fewer coefficients but also exhibited greater robustness to non-idealties. Furthermore, second-, fourth- and sixth-order single- and multi-path digital variable bandpass digital sigma-delta modulators are designed using this technique. The mathematical modelling and evaluation of tones caused by the finite wordlengths of these digital multi-path sigmadelta modulators, when excited by sinusoidal input signals, are also derived from first principles and verified using simulation and experimental results. The fourth-order digital variable-band sigma-delta modulator topologies are implemented in VHDL and synthesized on Xilinx® SpartanTM-3 Development Kit using fixed-point arithmetic. Circuit outputs were taken via RS232 connection provided on the FPGA board and evaluated using MATLAB routines developed by the author. These routines included the decimation process as well. The experiments undertaken by the author further validated the design methodology presented in the work. In addition, a novel tunable and reconfigurable second-order variable bandpass sigma-delta modulator has been designed and evaluated at the behavioural-level. This topology offers a flexible set of choices for designers and can operate either in single- or dual-mode enabling multi-band implementations on a single digital variable bandpass sigma-delta modulator. This work is also supported by a novel user-friendly design and evaluation tool that has been developed in MATLAB/Simulink that can speed-up the design, evaluation and comparison of analog and digital single-stage and time-interleaved variable bandpass sigma-delta modulators. This tool enables the user to specify the conversion type, topology, loop-filter type, path number and oversampling ratio.

Feminist Street Performances in Puerto Rico: Alternative Imaginaries Shifting the Ideal(ized) National Body

Thesis (Ph.D.)--University of Washington, 2016-08

Detailed analysis of a conservative difference approximation for the time fractional diffusion equation

Diffusion equations that use time fractional derivatives are attractive because they describe a wealth of problems involving non-Markovian Random walks. The time fractional diffusion equation (TFDE) is obtained from the standard diffusion equation by replacing the first-order time derivative with a fractional derivative of order α ∈ (0, 1). Developing numerical methods for solving fractional partial differential equations is a new research field and the theoretical analysis of the numerical methods associated with them is not fully developed. In this paper an explicit conservative difference approximation (ECDA) for TFDE is proposed. We give a detailed analysis for this ECDA and generate discrete models of random walk suitable for simulating random variables whose spatial probability density evolves in time according to this fractional diffusion equation. The stability and convergence of the ECDA for TFDE in a bounded domain are discussed. Finally, some numerical examples are presented to show the application of the present technique.