Differential polarization decoding for robust coherent optical packet switched networks

This paper proposes the use of the 2-D differential decoding to improve the robustness of dual-polarization optical packet receivers and is demonstrated in a wavelength switching scenario for the first time.

Direct sequence spread spectrum based PWM strategy for harmonic reduction and communication

Switched mode power supplies (SMPSs) are essential components in many applications, and electromagnetic interference is an important consideration in the SMPS design. Spread spectrum based PWM strategies have been used in SMPS designs to reduce the switching harmonics. This paper proposes a novel method to integrate a communication function into spread spectrum based PWM strategy without extra hardware costs. Direct sequence spread spectrum (DSSS) and phase shift keying (PSK) data modulation are employed to the PWM of the SMPS, so that it has reduced switching harmonics and the input and output power line voltage ripples contain data. A data demodulation algorithm has been developed for receivers, and code division multiple access (CDMA) concept is employed as communication method for a system with multiple SMPSs. The proposed method has been implemented in both Buck and Boost converters. The experimental results validated the proposed DSSS based PWM strategy for both harmonic reduction and communication.

Estudo da estrutura subsuperficial da província Borborema com correlação de ruído sísmico

Ambient seismic noise has traditionally been considered as an unwanted perturbation in seismic data acquisition that "contaminates" the clean recording of earthquakes. Over the last decade, however, it has been demonstrated that consistent information about the subsurface structure can be extracted from cross-correlation of ambient seismic noise. In this context, the rules are reversed: the ambient seismic noise becomes the desired seismic signal, while earthquakes become the unwanted perturbation that needs to be removed. At periods lower than 30 s, the spectrum of ambient seismic noise is dominated by microseism, which originates from distant atmospheric perturbations over the oceans. The microsseism is the most continuous seismic signal and can be classified as primary – when observed in the range 10-20 s – and secondary – when observed in the range 5-10 s. The Green‘s function of the propagating medium between two receivers (seismic stations) can be reconstructed by cross-correlating seismic noise simultaneously recorded at the receivers. The reconstruction of the Green‘s function is generally proportional to the surface-wave portion of the seismic wavefield, as microsseismic energy travels mostly as surface-waves. In this work, 194 Green‘s functions obtained from stacking of one month of daily cross-correlations of ambient seismic noise recorded in the vertical component of several pairs of broadband seismic stations in Northeast Brazil are presented. The daily cross-correlations were stacked using a timefrequency, phase-weighted scheme that enhances weak coherent signals by reducing incoherent noise. The cross-correlations show that, as expected, the emerged signal is dominated by Rayleigh waves, with dispersion velocities being reliably measured for periods ranging between 5 and 20 s. Both permanent stations from a monitoring seismic network and temporary stations from past passive experiments in the region are considered, resulting in a combined network of 33 stations separated by distances between 60 and 1311 km, approximately. The Rayleigh-wave, dispersion velocity measurements are then used to develop tomographic images of group velocity variation for the Borborema Province of Northeast Brazil. The tomographic maps allow to satisfactorily map buried structural features in the region. At short periods (~5 s) the images reflect shallow crustal structure, clearly delineating intra-continental and marginal sedimentary basins, as well as portions of important shear zones traversing the Borborema Province. At longer periods (10 – 20 s) the images are sensitive to deeper structure in the upper crust, and most of the shallower anomalies fade away. Interestingly, some of them do persist. The deep anomalies do not correlate with either the location of Cenozoic volcanism and uplift - which marked the evolution of the Borborema Province in the Cenozoic - or available maps of surface heat-flow, and the origin of the deep anomalies remains enigmatic.

Atmosferas arquitetônicas: projeto e percepção na obra de Peter Zumthor

This thesis will discuss the topic architectural atmospheres, based on Peter Zumthor's works and narrative. The subject "architectural atmospheres" is defined in the study as the "complex and general condition, realized by the user during the experience of a place". Atmospheres are composed of the overlap of all physical qualities that compound a space and its perception, conditioned by individual issues of the user. The atmosphere is realized through all human body receivers, in a multi-sensorial process, and affects qualitatively the spacial experience of the places created by architecture. The study has three chapters. The first chapter is a reflection on the issues that architectural atmospheres present. It passes through the concept and definition of the subject and includes a compilation of design principles that act on the architectural atmosphere composition in a variety of projects by a range of professionals. In the second chapter, the procedures adopted by Peter Zumthor in his design process that focus on atmosphere composition are studied. In the third and last chapter, Brother Claus Chapel (Wachendorf, German) and Kolumba Museum (Colon, German) projects, both by Peter Zumthor, are analyzed, in order to comprehend the complex role of elements that constitute the architectural atmosphere of each of these places. The methodology used throughout the thesis consists of bibliography and documental analysis, based on books, plans and material searched on Internet. Furthermore, the project analysis counted with the personal experience of the author of this thesis upon visiting the studied buildings. Finally, in conclusion, it is realized that when architecture is made in order to touch the user, expressed by its built objects, it can be provide a vast conceptual and theoretical basis that valorizes and enriches the experience of its use. It (the architectural atmosphere) is related to an approach that uses the same elements of any other construction, but distinguishes itself by the connections that it implies with humans and its environment. In the face of new patterns unveiled for contemporary architecture, this study contribution is based around the opportunity to understand this particular relationship between user and architectural object, identified as a phenomenological approach of architecture, as well as to update the subject bibliography, still scarce among Brazilian universities.

Medium change monitoring using ambient seismic noise and coda wave interferometry: examples from intraplate NE Brazil and the Mid-Atlantic Ridge

This thesis presents and discusses the results of ambient seismic noise correlation for two different environments: intraplate and Mid-Atlantic Ridge. The coda wave interferometry method has also been tested for the intraplate data. Ambient noise correlation is a method that allows to retrieve the structural response between two receivers from ambient noise records, as if one of the station was a virtual source. It has been largely used in seismology to image the subsurface and to monitor structural changes associated mostly with volcanic eruptions and large earthquakes. In the intraplate study, we were able to detect localized structural changes related to a small earthquake swarm, which main event is mR 3.7, North-East of Brazil. We also showed that the 1-bit normalization and spectral whitening result on the loss of waveform details and that the phase auto-correlation, which is amplitude unbiased, seems to be more sensitive and robust for our analysis of a small earthquake swarm. The analysis of 6 months of data using cross-correlations detect clear medium changes soon after the main event while the auto-correlations detect changes essentially after 1 month. It could be explained by fluid pressure redistribution which can be initiated by hydromechanical changes and opened path ways to shallower depth levels due to later occurring earthquakes. In the Mid-Atlantic Ridge study, we investigate structural changes associated with a mb 4.9 earthquake in the region of the Saint Paul transform fault. The data have been recorded by a single broadband seismic station located at less than 200 km from the Mid-Atlantic ridge. The results of the phase auto-correlation for a 5-month period, show a strong co-seismic medium change followed by a relatively fast post-seismic recovery. This medium change is likely related to the damages caused by the earthquake’s ground shaking. The healing process (filling of the new cracks) that lasted 60 days can be decomposed in two phases, a fast recovery (70% in ~30 days) in the early post-seismic stage and a relatively slow recovery later (30% in ~30 days). In the coda wave interferometry study, we monitor temporal changes of the subsurface caused by the small intraplate earthquake swarm mentioned previously. The method was first validated with synthetics data. We were able to detect a change of 2.5% in the source position and a 15% decrease of the scatterers’ amount. Then, from the real data, we observed a rapid decorrelation of the seismic coda after the mR 3.7 seismic event. This indicates a rapid change of the subsurface in the fault’s region induced by the earthquake.

Medium change monitoring using ambient seismic noise and coda wave interferometry: examples from intraplate NE Brazil and the Mid-Atlantic Ridge

This thesis presents and discusses the results of ambient seismic noise correlation for two different environments: intraplate and Mid-Atlantic Ridge. The coda wave interferometry method has also been tested for the intraplate data. Ambient noise correlation is a method that allows to retrieve the structural response between two receivers from ambient noise records, as if one of the station was a virtual source. It has been largely used in seismology to image the subsurface and to monitor structural changes associated mostly with volcanic eruptions and large earthquakes. In the intraplate study, we were able to detect localized structural changes related to a small earthquake swarm, which main event is mR 3.7, North-East of Brazil. We also showed that the 1-bit normalization and spectral whitening result on the loss of waveform details and that the phase auto-correlation, which is amplitude unbiased, seems to be more sensitive and robust for our analysis of a small earthquake swarm. The analysis of 6 months of data using cross-correlations detect clear medium changes soon after the main event while the auto-correlations detect changes essentially after 1 month. It could be explained by fluid pressure redistribution which can be initiated by hydromechanical changes and opened path ways to shallower depth levels due to later occurring earthquakes. In the Mid-Atlantic Ridge study, we investigate structural changes associated with a mb 4.9 earthquake in the region of the Saint Paul transform fault. The data have been recorded by a single broadband seismic station located at less than 200 km from the Mid-Atlantic ridge. The results of the phase auto-correlation for a 5-month period, show a strong co-seismic medium change followed by a relatively fast post-seismic recovery. This medium change is likely related to the damages caused by the earthquake’s ground shaking. The healing process (filling of the new cracks) that lasted 60 days can be decomposed in two phases, a fast recovery (70% in ~30 days) in the early post-seismic stage and a relatively slow recovery later (30% in ~30 days). In the coda wave interferometry study, we monitor temporal changes of the subsurface caused by the small intraplate earthquake swarm mentioned previously. The method was first validated with synthetics data. We were able to detect a change of 2.5% in the source position and a 15% decrease of the scatterers’ amount. Then, from the real data, we observed a rapid decorrelation of the seismic coda after the mR 3.7 seismic event. This indicates a rapid change of the subsurface in the fault’s region induced by the earthquake.

Meating the social: sharing atiku-euiash in Sheshatshiu, Labrador

This work examines atiku-euiash (caribou meat) sharing practices in Sheshatshiu, Newfoundland and Labrador, and aims to elucidate an overarching question: how do sharing practices participate in the co-constitution of the Innu ‘social’? The ‘social’ is understood in this work as a descriptor that refers to the emergent properties of the Innu collective. The thesis is that sharing practices participate in the co-constitution of the Innu social and enact its boundaries. Inside these boundaries, atiku-euiash is more than simply a food resource: by realizing Innu values of generosity, respect and autonomy, sharing implicates the associations of human, animal, and animal masters that constitute the Innu world. Sharing is connected with the enskilment of the younger generations by their el-ders, and thus with the reproduction of Innu values through time. The ways of sharing are relevant because changes in such practices affect the constitution of the Innu social. Giv-en Euro-Canadian colonization, the Innu are in a fraught social space in which sharing is interrupted by colonization practices and values. Understanding sharing is necessary to develop policies that do not interrupt the reproduction of the Innu world This work uses several research methods: participant observation, sharing surveys, and interviews. It also uses network analysis as sharing practices leave traces of giving and receiving actions and these traces can be represented as a network of givers, receivers and circulating caribou meat. There are two main ways in which caribou is hunted and shared: household-based hunts and community-based hunts. The household-based hunts are organized by the hunters themselves, who are able and willing to hunt. Community-based hunts are completely organized and funded by the SIFN or the Innu Nation. In or-der to understand the differences in the distribution of the two hunt types, the categories of centrality and clustering are used to show how the flow of atiku-eiuash and its associ-ated realization of values and enskilment correlate with different degrees of centralization inside the sharing clusters.

AS INOVAÇÕES TECNOLÓGICAS E OS INTERMEDIÁRIOS DA PRODUÇÃO E DO ACESSO À INFORMAÇÃO JORNALÍSTICA

O jornalismo é um dos principais meios de oferta de temas para a discussão e formação da opinião pública, porém depende de um sistema técnico para ser transmitido. Durante mais de cem anos as informações produzidas pela imprensa foram emitidas, armazenadas, transmitidas e recebidas pelos chamados veículos de comunicação de massa que utilizam a rede centralizada cujas características estão na escassez material, produção em série e massificação. Esse sistema separa no tempo e no espaço emissores e receptores criando uma relação desigual de força em que as grandes empresas controlaram o fluxo informativo, definindo quais fatos seriam veiculados como notícia. Em 1995, a internet cuja informação circula sob a tecnologia da rede distribuída, foi apropriada pela sociedade, alterando a forma de produção, armazenamento e transmissão de informação. A tecnologia despertou a esperança de que esta ferramenta poderia proporcionar uma comunicação mais dialógica e democrática. Mas aos poucos pode-se perceber novas empresas se apropriando da tecnologia da rede distribuída sob a qual circula a internet, gerando um novo controle do fluxo informativo. Realizou-se nessa pesquisa um levantamento bibliográfico para estabelecer uma reflexão crítica dos diferentes intermediários entre fato e a notícia tanto da rede centralizada como na rede distribuída, objetivando despertar uma discussão que possa oferecer novas ideias para políticas, bem como alternativas para uma comunicação mais democrática e mais libertária.

Quality of transmission estimation in WDM and elastic optical networks accounting for space-spectrum dependencies

We develop a framework for estimating the quality of transmission (QoT) of a new lightpath before it is established, as well as for calculating the expected degradation it will cause to existing lightpaths. The framework correlates the QoT metrics of established lightpaths, which are readily available from coherent optical receivers that can be extended to serve as optical performance monitors. Past similar studies used only space (routing) information and thus neglected spectrum, while they focused on oldgeneration noncoherent networks. The proposed framework accounts for correlation in both the space and spectrum domains and can be applied to both fixed-grid wavelength division multiplexing (WDM) and elastic optical networks. It is based on a graph transformation that exposes and models the interference between spectrum-neighboring channels. Our results indicate that our QoT estimates are very close to the actual performance data, that is, to having perfect knowledge of the physical layer. The proposed estimation framework is shown to provide up to 4 × 10-2 lower pre-forward error correction bit error ratio (BER) compared to theworst-case interference scenario,which overestimates the BER. The higher accuracy can be harvested when lightpaths are provisioned with low margins; our results showed up to 47% reduction in required regenerators, a substantial savings in equipment cost.

RF MIMO Systems for Wide-Area Indoor Human Motion Monitoring

Human motion monitoring is an important function in numerous applications. In this dissertation, two systems for monitoring motions of multiple human targets in wide-area indoor environments are discussed, both of which use radio frequency (RF) signals to detect, localize, and classify different types of human motion. In the first system, a coherent monostatic multiple-input multiple-output (MIMO) array is used, and a joint spatial-temporal adaptive processing method is developed to resolve micro-Doppler signatures at each location in a wide-area for motion mapping. The downranges are obtained by estimating time-delays from the targets, and the crossranges are obtained by coherently filtering array spatial signals. Motion classification is then applied to each target based on micro-Doppler analysis. In the second system, multiple noncoherent multistatic transmitters (Tx's) and receivers (Rx's) are distributed in a wide-area, and motion mapping is achieved by noncoherently combining bistatic range profiles from multiple Tx-Rx pairs. Also, motion classification is applied to each target by noncoherently combining bistatic micro-Doppler signatures from multiple Tx-Rx pairs. For both systems, simulation and real data results are shown to demonstrate the ability of the proposed methods for monitoring patient repositioning activities for pressure ulcer prevention.

Position measurements at five permanent GPS stations in the Bavarian Alps as part of the Geodetic Alpine Integrated Network (GAIN) of the ALPS-GPSQUAKENET project

In the frame of the transnational ALPS-GPSQUAKENET project, a component of the Alpine Space Programme of the European Community Initiative Programme (CIP) INTERREG III B, the Deutsches Geodätisches Forschungsinstitut (DGFI) in Munich, Germany, installed in 2005 five continuously operating permanent GPS stations located along the northern Alps boundary in Bavaria. The main objective of the ALPS-GPSQUAKENET project was to build-up a high-performance transnational space geodetic network of Global Positioning System (GPS) receivers in the Alpine region (the so-called Geodetic Alpine Integrated Network, GAIN). Data from this network allows for studying crustal deformations in near real-time to monitor Earthquake hazard and improve natural disaster prevention. The five GPS stations operatied by DGFI are mounted on concrete pillars attached to solid rock. The names of the stations are (from west to east) Hochgrat (HGRA), Breitenberg (BREI), Fahrenberg (FAHR), Hochries (HRIE) and Wartsteinkopf (WART). The provided data series start from October 7, 2005. Data are stored with a temporal spacing of 15 seconds in daily RINEX files.

(Table T4) Final depth vs. velocity and two-way traveltime data, ODP Site 178-1103

Site 1103 was one of a transect of three sites drilled across the Antarctic Peninsula continental shelf during Leg 178. The aim of drilling on the shelf was to determine the age of the sedimentary sequences and to ground truth previous interpretations of the depositional environment (i.e., topsets and foresets) of progradational seismostratigraphic sequences S1, S2, S3, and S4. The ultimate objective was to obtain a better understanding of the history of glacial advances and retreats in this west Antarctic margin. Drilling the topsets of the progradational wedge (0-247 m below seafloor [mbsf]), which consist of unsorted and unconsolidated materials of seismic Unit S1, was very unfavorable, resulting in very low (2.3%) core recovery. Recovery improved (34%) below 247 mbsf, corresponding to sediments of seismic Unit S3, which have a consolidated matrix. Logs were only obtained from the interval between 75 and 244 mbsf, and inconsistencies on the automatic analog picking of the signals received from the sonic log at the array and at the two other receivers prevented accurate shipboard time-depth conversions. This, in turn, limited the capacity for making seismic stratigraphic interpretations at this site and regionally. This study is an attempt to compile all available data sources, perform quality checks, and introduce nonstandard processing techniques for the logging data obtained to arrive at a reliable and continuous depth vs. velocity profile. We defined 13 data categories using differential traveltime information. Polynomial exclusion techniques with various orders and low-pass filtering reduced the noise of the initial data pool and produced a definite velocity depth profile that is synchronous with the resistivity logging data. A comparison of the velocity profile produced with various other logs of Site 1103 further validates the presented data. All major logging units are expressed within the new velocity data. A depth-migrated section with the new velocity data is presented together with the original time section and initial depth estimates published within the Leg 178 Initial Reports volume. The presented data confirms the location of the shelf unconformity at 222 ms two-way traveltime (TWT), or 243 mbsf, and allows its seismic identification as a strong negative and subsequent positive reflection.

A Decade-Bandwidth Low-Noise Mixer RFIC with a Distortion-Canceling Output Amplifier

This paper presents a 1-10 GHz low-noise downconvert mixer RFIC suitable for wideband receivers. A switched transconductor mixing core is adopted to reduce noise at high frequencies. By adding a series inductor to the RF transconductor, a flat 4-5 dB noise figure (NF) and a high gain of 26.5 dB can be achieved over a broad bandwidth out to 10 GHz. A CMOS output amplifier is also integrated on-chip, employing derivative superposition (DS) for high linearity and an OIP3 of 16.5 dBm. The circuit consumes less than 20 mW of dc power and occupies an active chip area of less than 0.2 mm2.

“Considering there’s supposedly nothing wrong with me, it’s not a life”: Women’s Narratives of Distress, Visiting Herbalists, and Being Well in the 21st Century

Distress can have a profoundly negative impact on the well-being of women (who are the main receivers of treatment for distress). Distress also poses a huge financial problem for the United Kingdom, the cost of which is predicted to reach over £26bn by 2026. A growing body of research has shown that various medicinal plants have potential to treat different aspects of distress. However, there is little research investigating the patient experience of western herbal practice (WHP), and none investigating women’s experiences of WHP for distress. In response, this longitudinal study utilised interviews with twenty-six women who were visiting herbalists for distress across the south-east of The United Kingdom to elicit their stories of distress, as well as their experiences of WHP. The narratives were analysed from a constructionist standpoint, using inductive thematic analysis. The participants’ narratives highlighted the profound impact of everyday distress, whilst feelings associated with distress (anxiety, low mood, isolation, shame and guilt) were frequently communicated via the use of metaphors. These negative feelings, often combined with unsuccessful biomedical encounters, frequently led to the women feeling desperate when first visiting a herbalist. The participants’ experiences of WHP showed that an accessible practitioner and good therapeutic relationship combined with flexible herbal treatment, allowed women with diverse stories of distress to overcome feelings of desperation. Ongoing support allowed the women to feel like they had a safety net as they journeyed from a place of distress, back into the wider world. These findings were supported by more unusual negative accounts, which showed how the herbal therapeutic process could be unsuccessful if elements were missing. This research is of significance as it helps to deepen our understanding of women’s experiences of distress – particularly perceptions of stigma which surround feelings of shame (linked to an inability to cope) and guilt (linked to the perceived impact of distress on others). The research also has relevance for WHP, as it highlights which positive aspects of WHP are of particular importance to women patients who are living with distress.

Entre reglas y excepciones. Es decir, como legitimar las decisiones colectivas

El ensayo examina la cuestión de la aplicación de las reglas y de la capacidad real para tratar casos específicos, llegando a la conclusión de que es la excepción la que confirma la regla, a condición de que sea dialógicamente construida, para que sea interpretable y aplicable por parte de sus numerosos destinatarios en las políticas públicas más complejas y conflictuales, sobre todo a nivel local.