Academic literature on the topic 'Signal path analysis'

We present a scheme for modeling HF radio signal characteristics along paths of different lengths, which is based on the waveguide approach — the normal mode method. We use a representation of the recorded signal field in the form of Green function products of the angular operator, excitation coefficients, and reception coefficients of individual normal modes. Algorithms have been developed for calculating distance-frequency, frequency-angular, and amplitude characteristics of signals in large spatial regions through analysis and numerical summation of normal mode series. We have implemented a complex algorithm for simulating propagation conditions of HF radio signals, which includes a medium model, algorithms for calculating signal characteristics, and operational diagnostics of radio channel. We have compared the results of the HF signal propagation characteristic modeling and the experimental oblique sounding data obtained along paths of different lengths and orientation. To analyze experimental ionograms, determine the maximum usable frequencies for propagation modes along radio paths, we employ the method of automatic processing and interpretation of oblique sounding ionograms.

Having given a short overview of GNSS signals and state-of-the-art multi-band front-end architectures, this paper presents a novel contribution to efficient multi-band GNSS reception. A general overlay based front-end architecture is introduced that enables the joint reception of two signals broadcast in separate frequency bands, sharing just one common baseband stage. The consequences of this overlay are analyzed for both signal and noise components. Signal overlay is shown to have a negligible impact on signal quality. It is shown that the noise floor superposition results in non-negligible degradations. However, it is also demonstrated that these degradations can be minimized by judiciously setting the relative gain between the two signal paths. As an illustration, the analytical optimal path-control expression to combine overlaid signals in an ionospheric-free pseudorange is derived for both Cramér-Rao Lower Bound and practical code tracking parameters. Finally, some practical overlay receiver and path control aspects are discussed.

It is impossible to overstate the importance of propagation models in wireless network planning, frequency assignment, and television parameter evaluation. The fact that no two locations are identical in terms of climatic conditions, building patterns, terrain, etc. makes using path loss predicting models for any area extremely challenging. Therefore, it is impossible to develop a single path loss model that applies to all environmental settings. The main aim of this study is to develop a path loss model for NTA channel 12 Owerri and evaluate its performance based on received signal strength values along five selected routes in Imo State, Nigeria.A suitable path loss model was developed by critically analyzing the measured path loss values of each base station, which were retrieved from the signal strength data received. The values of the developed path loss model were compared to those of other empirical path loss models developed by other researchers as well as the measured path loss values. The results show that the proposed path loss model is well suited for predicting the path loss of NTA channel 12 Owerri signals in the study environment, while the other conventional empirical models taken into consideration in this study overestimated the path loss of NTA channel 12 Owerri signals with Root Mean Square Error and Mean Error of 63.65 and above. Additionally, the findings indicate that NTA Owerri performs poorly at a distance of 18 kilometers from the base transmitting station. The overall findings are helpful for designing prospective television network channels in the study location and other similar environments.

In active vibration control, most of the signals to be eliminated are deterministic signals. Simulations are carried out using periodic sinusoidal reference signal based on FxLMS algorithm. Based on a deterministic reference signal input conditions, the paper provides a detailed behavior analysis due to the secondary-path model error and phase delay, the results will give theoretical basis by adjusting the FxLMS algorithm parameters to ensure convergence and to achieve the best control performance in practical applications.

Legs are the contact point of humans during walking. In fact, leg muscles react when we walk in different conditions (such as different speeds and paths). In this research, we analyze how walking path affects leg muscles’ reaction. In fact, we investigate how the complexity of muscle reaction is related to the complexity of path of movement. For this purpose, we employ fractal theory. In the experiment, subjects walk on different paths that have different fractal dimensions and then we calculate the fractal dimension of Electromyography (EMG) signals obtained from both legs. The result of our analysis showed that the complexity of EMG signal increases with the increment of complexity of path of movement. The conducted statistical analysis also supported the result of analysis. The method of analysis used in this research can be further applied to find the relation between complexity of path of movement and other physiological signals of humans such as respiration and Electroencephalography (EEG) signal.

We present a scheme for modeling HF radio signal characteristics along paths of different lengths, which is based on the waveguide approach — the normal mode method. We use a representation of the recorded signal field in the form of Green function products of the angular operator, excitation coefficients, and reception coefficients of individual normal modes. Algorithms have been developed for calculating distance-frequency, frequency-angular, and amplitude characteristics of signals in large spatial regions through analysis and numerical summation of normal mode series. We have implemented a complex algorithm for simulating propagation conditions of HF radio signals, which includes a medium model, algorithms for calculating signal characteristics, and operational diagnostics of radio channel. We have compared the results of the HF signal propagation characteristic modeling and the experimental oblique sounding data obtained along paths of different lengths and orientation. To analyze experimental ionograms, determine the maximum usable frequencies for propagation modes along radio paths, we employ the method of automatic processing and interpretation of oblique sounding ionograms.

There are significant concerns for the citizens of Okene and its surroundings; regarding the distortions experienced in radio signals due to increased attenuation, which have resulted in poor signal quality. This study carried out a comparative analysis of the signal strength of two radio broadcast stations in Okene, Kogi State, Nigeria, using a field strength meter. The study involved measuring the signal strength for each radio stations at six selected locations in Okene and surrounding area. The wavelength and free space path-loss was calculated at sixteen different locations. The results indicated an inverse relationship between the measured signal strengths and the path-loss, as well as the approximate distance amid antennas. The transmitting signal strength was 100.9dBµV (KA) and 102.2dBµV (KB). Distance from station where signal can be receive was 72.0km (KA) and 69.0km (KB). The free space path loss experienced was 109.01dB (KA) and 109.39dB (KB). Even though KA has a lower transmitting signal strength, its longer wavelength 3.21m and lower frequency 93.5MHz gives it an age over KB with higher frequency 109.5MHz and shorter wavelength 2.94m. However, it is recommended that the FM stations should strategically enhance their network infrastructure to improve service delivery, particularly where performance lags. Booster stations at approximately 69km away from the main stations can effectively enhance the signal, leading to better signal quality and improved customer satisfaction.

This paper presents a path-loss model based on a radio-frequency (RF) detection scheme for various drones using 5G aerial communication over an industrial, scientific, and medical radio band (ISM band) network. We considered three communication modes of the ISM band for the channel characteristics analysis: the DJI Enhanced Spread Spectrum Technology (DESST) protocol, Wi-Fi, and Bluetooth. The drone signal detection scheme extracts the drone signal from the environment mixed with the general signal. The drone DESST signal is identified through cross-correlation of the received signal. The Wi-Fi and Bluetooth signals are identified with the singular-value decomposition (SVD) algorithm by using the hopping characteristics. General and drone Wi-Fi signals are separated by in-phase/quadrature (I/Q) phase analysis over the measurement time. The windowed received signal strength indicator (RSSI) moving detection (WRMD) analysis identifies the drone Bluetooth signal according to the movement of the drone. The detected drone signal is channel modeled by the horizontal distance d according to the altitude θ. Finally, they verify their model by a ray-tracing simulation similar to the real environment. The model provides a simple and accurate prediction for designing future aerial communications systems according to changes in drone movement.

The signal power in wireless communication systems is influenced by various factors, including the environment. These factors include path differences, operational frequency, and environmental conditions. Consequently, designing a communication system that generates a stronger signal is highly challenging. To address this, large-scale path-loss models are employed to estimate the path loss and signal power across different frequencies, distances, and environments. In this paper, we focused on the urban micro, urban macro, and rural macro environments to estimate path loss and signal power at millimeter wave frequencies. We compared the path loss and received power among different path-loss models developed by standard organizations. Simulation results indicate that the fifth-generation channel model provides enhanced path loss and signal power in urban micro environments, while the third-generation partnership project model performs well in urban macro and rural macro environments when compared to other path-loss models.

In a typical multipath propagation environment, there exists a strong direct path signal accompanying with several weak multipath signals. Due to the strong direct path interference and other masking effects, the Direction-of-Arrival (DOA) of a weak multipath signal is hard to be estimated. In this paper, a novel method is proposed to estimate the DOA of multipath signals with ultralow signal-to-noise ratio (SNR). The main idea is to increase the SNR and signal-to-interference ratio (SIR) of the desired multipath signal in time-delay domain before DOA estimation processing. Firstly, the cross-correlation functions of the direct path signal and the received array signal are calculated. Then, they are combined and constructed to an enhanced array signal. Under certain conditions, the SNR and SIR of the desired signal can be significantly increased. Finally, the DOAs of multipath signals can be estimated by conventional technologies, and the associated time delays can be measured on the DOA-time-shift map. The SNR and SIR gains of the desired signal are analyzed theoretically, and theoretical analysis also indicates that the Cramer–Rao bound can be reduced. Simulation examples are presented to verify the advantages of the proposed method.

Global Navigation Satellite Systems can provide position, velocity and time information to users using receiver hardware. The United States developed Global Positioning System (GPS) is the only current fully operational system; however further systems are in development. The GPS has shown considerable success for navigation, but it still has a number of problems that limit its accuracy. The two main problems are the ionosphere and local environment of the receiver. The ionosphere causes a delay and random rapid shifts in phase and amplitude (scintillation) to the signal. The local environment can provide the signal with multiple routes (multi-path) to the receiver. In this project a GPS signal simulator is developed, which models the effects of the ionosphere and multi-path on the modulated signals. The focus is made on the GPS system as the simulator measurements can be compared to the real measurements; however other systems will be considered in the future. A number of experiments investigating multi-path and ionospheric effects on a receiver’s ability to track the signals have been completed. The simulator has been used to replicate a real local multi-path environment and the results have been compared. Further investigations of the multi-path have shown a unique multi-path signature in the receiver power output. The later part of the thesis describes a case study investigating a short but rapid period of scintillation observed on three receivers based in Norway. An analysis of the multi-path environment was completed, but was found not to be the cause. The ionosphere was investigated using equipment based across Scandinavia. The equipment showed that geomagnetic conditions were disturbed at the time of the event. The GPS measurements were compared with all-sky camera data to show that the scintillation can be attributed to the GPS signal path crossing electron density structures associated with the aurora.

Introduced in this paper is the time difference of arrival (TDoA) conic approximation method (TCAM), a technique for passive localization in three dimensions with unknown starting conditions. The TDoA of a mutually detected signal across pairs of detectors is used to calculate the relative angle between the signal source and the center point of the separation between the detectors in the pair. The relative angle is calculated from the TDoA using a mathematical model called the TDoA approximation of the zenith angle (TAZA). The TAZA angle defines the opening angle of a conic region of probability that contains the signal source, produced by each detector pair. The intersecting region of probability is determined from the conic regions of probability and represents the volumetric region with the highest probability of containing the signal source. TCAM was developed and tested using synthetic data in a simulated environment.

The dissertation concerns about the path loss calculation of Radio Frequency (RF) propagation models for 4G Long Term Evolution (LTE) Network to prefer the best Radio Frequency propagation model. The radio propagation models are very significant while planning of any wireless communication system. A comparative analysis between radio propagation models e.g. SUI model, Okumura model, Cost 231 Hata Model, Cost 231-Walfisch Ikegami and Ericsson 9999 model that would be used for outdoor propagation in LTE. The comparison and performance analysis has been made by using different geological environments e.g. urban, sub-urban and rural areas. The simulation scenario is made to calculate the lowest path loss in above defined environments by using selected frequency and height of base station antennas while keeping a constant distance between the transmitter and receiver antennas.<br>Asad Saeed C/O Muhammad Awais Hovslagargatan 47 LGH 1004 19431 Stockholm Sweden Mob: 0046723333734

In the production of paper, the quality of the pulp is an important factor both for the productivity and for the final quality. Reliable real-time measurements of pulp quality are therefore needed. One way is to use acoustic or vibration sensors that give information-rich signals and place the sensors at suitable locations in a pulp production line. However, these sensors are not selective for the pulp properties of interest. Therefore, advanced signal processing and multivariate calibration are essential tools. The current work has been focused on the development of calibration routes for extraction of information from acoustic sensors and on signal processing algorithms for enhancing the information-selectivity for a specific pulp property or class of properties. Multivariate analysis methods like Principal Components Analysis (PCA), Partial Least Squares (PLS) and Orthogonal Signal Correction (OSC) have been used for visualization and calibration. Signal processing methods like Fast Fourier Transform (FFT), Fast Wavelet Transform (FWT) and Continuous Wavelet Transform (CWT) have been used in the development of novel signal processing algorithms for extraction of information from vibrationacoustic sensors. It is shown that use of OSC combined with PLS for prediction of Canadian Standard Freeness (CSF) using FFT-spectra produced from vibration data on a Thermo Mechanical Pulping (TMP) process gives lower prediction errors and a more parsimonious model than PLS alone. The combination of FFT and PLS was also used for monitoring of beating of kraft pulp and for screen monitoring. When using regular FFT-spectra on process acoustic data the obtained information tend to overlap. To circumvent this two new signal processing methods were developed: Wavelet Transform Multi Resolution Spectra (WT-MRS) and Continuous Wavelet Transform Fibre Length Extraction (CWT-FLE). Applying WT-MRS gave PLS-models that were more parsimonious with lower prediction error for CSF than using regular FFT-Spectra. For a Medium Consistency (MC) pulp stream WT-MRS gave predictions errors comparable to the reference methods for CSF and Brightness. The CWT-FLE method was validated against a commercial fibre length analyzer and good agreement was obtained. The CWT-FLE-curves could therefore be used instead of other fibre distribution curves for process control. Further, the CWT-FLE curves were used for PLS modelling of tensile strength and optical parameters with good results. In addition to the mentioned results a comprehensive overview of technologies used with acoustic sensors and related applications has been performed.<br>Vid framställning av pappersprodukter är kvaliteten på massan en viktig faktor för produktiviteten och kvalitén på slutresultatet. Det är därför viktigt att ha tillgång till tillförlitliga mätningar av massakvalitet i realtid. En möjlighet är att använda akustik- eller vibrationssensorer i lämpliga positioner vid enhetsoperationer i massaprocessen. Selektiviteten hos dessa mätningar är emellertid relativt låg i synnerhet om mätningarna är passiva. Därför krävs avancerad signalbehandling och multivariat kalibrering. Det nu presenterade arbetet har varit fokuserat på kalibreringsmetoder för extraktion av information ur akustiska mätningar samt på algoritmer för signalbehandling som kan ge förbättrad informationsselektivitet. Multivariata metoder som Principal Component Analysis (PCA), Partial Least Squares (PLS) and Orthogonal Signal Correction (OSC) har använts för visualisering och kalibrering. Signalbehandlingsmetoderna Fast Fourier Transform (FFT), Fast Wavelet Transform (FWT) och Continuous Wavelet Transform (CWT) har använts i utvecklingen av nydanande metoder för signalbehandling anpassade till att extrahera information ur signaler från vibrations/akustiska sensorer. En kombination av OSC och PLS applicerade på FFT-spektra från raffineringen i en Termo Mechnaical Pulping (TMP) process ger lägre prediktionsfel för Canadian Standard Freeness (CSF) än enbart PLS. Kombinationen av FFT och PLS har vidare använts för monitorering av malning av sulfatmassa och monitorering av silning. Ordinära FFT-spektra av t.ex. vibrationssignaler är delvis överlappande. För att komma runt detta har två signalbehandlingsmetoder utvecklats, Wavelet Transform Multi Resolution Spectra (WT-MRS) baserat på kombinationen av FWT och FFT samt Continuous Wavelet Transform Fibre Length Extraction (CWT-FLE) baserat på CWT. Tillämpning av WT-MRS gav enklare PLS-modeller med lägre prediktionsfel för CSF jämfört med att använda normala FFT-spektra. I en annan tillämpning på en massaström med relativt hög koncentration (Medium Consistency, MC) kunde prediktioner för CSF samt ljushet erhållas med prediktionsfel jämförbart med referensmetodernas fel. Metoden CWT-FLE validerades mot en kommersiell fiberlängdsmätare med god överensstämmelse. CWT-FLE-kurvorna skulle därför kunna användas i stället för andra fiberdistributionskurvor för processtyrning. Vidare användes CWT-FLE kurvor för PLS modellering av dragstyrka samt optiska egenskaper med goda resultat. Utöver de nämnda resultaten har en omfattande litteratursammanställning gjorts över området och relaterade applikationer.<br>QC 20100629

Au 20ème siècle, les massifs montagneux, dont les Alpes, ont connu un réchauffement significatif avec une augmentation des températures deux fois plus importante que la moyenne mondiale. Un tel réchauffement altère les composantes de la cryosphère. Elle induit, par exemple, un passage des précipitations solides aux précipitations liquides, des phases de fonte des neiges plus fréquentes et plus intenses, ainsi qu’une forte diminution de la quantité de neige et une réduction de la durée de la couverture neigeuse. Aux horizons 2050–2100, les modèles climatiques prévoient que l'épaisseur du manteau neigeux sera considérablement réduite et que les propriétés de la neige, et notamment la stabilité du manteau neigeux, seront modifiées. Ces changements devraient entraîner des modifications importantes dans l'activité des avalanches. Parallèlement, l’afforestation induite par la déprise agro-sylvo-pastorale, la démocratisation des sports d'hiver et l'urbanisation des versants ont profondément modifié les paysages de montagne depuis le milieu du 18ème siècle, de même que l'exposition des individus. Dans ce contexte, une documentation précise de l'activité passée des avalanches est cruciale pour mettre en évidence et comprendre les impacts du réchauffement climatique sur l'activité avalancheuse. Jusqu'à présent, cette documentation s'appuyait sur des chroniques historiques ou des observations systématiques. Cependant, les premières sont souvent discontinues et axées sur des événements catastrophiques, tandis que les secondes se limitent à la seconde moitié du 20ème siècle, excluant toute comparaison avec des périodes climatiques distinctes – tel que les phases froides du Petit Âge Glaciaire, par exemple. Sur les versants forestiers, l'approche dendrogéomorphique apparaît être un complément fiable aux archives historiques et aux séries d'observations systématiques, car elle permet de reconstruire l'activité passée des avalanches, en continu, à l‘échelle des plusieurs siècles, avec une résolution annuelle. Pourtant, jusqu'à présent, même si de nombreuses reconstructions locales ont été proposées, la fiabilité de l’approche a été peu souvent analysée et aucune chronologie régionale – cruciale pour distinguer les interférences potentielles entre l'activité des avalanches, les fluctuations climatiques et les changements socio-économiques – n'a été développée dans les Alpes. Dans cette thèse de doctorat, des avancées méthodologiques significatives ont été réalisées afin (1) d’améliorer la détection des avalanches dans les cernes de croissance, (2) d’éliminer les non-stationnarités liées à la diminution du nombre d'arbres au cours du temps dans les reconstructions et (3) d’agréger les reconstructions locales en chronologies régionales. Sur la base de ces développements, des chronologies régionales pluriséculaires homogénéisées ont été développées (4) pour 10 couloirs d’avalanche de la vallée de Goms (Valais, Alpes suisses, 1880-2014) et (5) 11 couloirs du massif du Queyras (Alpes françaises, 1560-2016). Ces dernières ont été confrontées aux fluctuations climatiques et aux changements d'occupation du sol. À Goms, l'absence de signal climatique clair dans la chronologie régionale souligne les interférences induites par les non-stationnarités locales et démontre qu’une stratégie d'échantillonnage à l'échelle régionale devra nécessairement constituer un préalable au développement d’une chronologie robuste. Dans le massif du Queyras, la forte diminution de l'activité avalancheuse observée au cours du 20ème siècle est attribuée au réchauffement climatique et au processus d’afforestation des versants<br>For the 20th century, high mountain areas, such as the Alps, have undergone a significant warming with temperature increase twice as much as the global average. Such warming strongly alters the cryosphere components. It induces, for example, a shift from solid to liquid precipitation, more frequent and more intense snowmelt phases or a strong decrease in the amount and duration of snow cover, especially at the elevation of the snowrain transition. In the future, climate models forecast that snow depth will be significantly reduced and that snow properties such as snow stability will be modified. These changes in snow cover characteristics and amounts are expected to induce significant changes in snow avalanches activity. At the same time, afforestation induced by the abandonment of agriculture and grazing, the democratization of winter recreation activities and the urban sprawl on the slopes have strongly modified the mountain landscapes since the mid-18th century as well as the exposition of individuals to snow avalanches. In this context, a precise documentation of past snow avalanche activity is crucial to decipher and to understand the impacts of the undergoing climate warming on the snow avalanche activity. To date, this documentation usually relies on historical chronicles or systematic observations. However, the firsts are often discontinuous and focused on catastrophic events. The seconds are limited to the second half of the 20th century thus precluding a comparison from climatically distinct period. On forested paths, the dendrogeomorphic approach is theoretically a reliable approach complement to historical archives and series of systematic observation to infer past snow avalanche activity. Yet, so far, the robustness of this approach has been poorly questioned and no regional chronology, crucial to disentangle potential interferences between snow avalanche activity, climate fluctuations and socio-economic changes, has been developed in the Alps. In this PhD thesis proposes new methodological frameworks to (1) detect avalanche events from tree-ring series, (2) remove non-stationarities related to the decreasing number of trees over time in the reconstruction and (3) aggregate locals reconstructions in regional chronologies. Based on these development, homogenized multicentennial regional chronologies developed (4) for 10 paths of the Goms Valley (Valais canton, Swiss Alps, 1880-2014) and (5) 11 paths from the Queyras Massif (French Alps, 1560-2016) are confronted to climatic fluctuations and land use changes. At Goms, the absence of clear climatic signal in the regional chronology evidence the interference with local nonstationarities and question the need for a sampling strategy at the regional scale to create a robust chronology. In the Queyras massif, the strong decrease of avalanche activity observed over the 20th century is attributed to global warming and to the afforestation process

Patch clamp recording in brain slices allows unparalleled access to neuronal membrane signals in a system that approximates the in-vivo neural substrate while affording greater control of experimental conditions. In this chapter we discuss the theory, methodology, and practical considerations of such experiments including the initial setup, techniques for preparing and handling viable brain slices, and patching and recording signals. A number of practical and technical issues faced by electrophysiologists are also considered, including maintaining slice viability, visualizing and identifying healthy cells, acquiring reliable patch seals, amplifier compensation features, hardware configuration, sources of electrical noise and table vibration, as well as basic data analysis issues and some troubleshooting tips.

The work Discursive memory on gender violence in the voice of women with disabilities originated from the Master of Arts in Literature research developed by Flávia Pieretti Cardoso, under the guidance of professors Maria Leda Pinto and Léia Teixeira Lacerda, at the State University of Mato Grosso do Sul. In her role as an interpreter of Brazilian Sign Language at the Casa da Mulher Brasileira and her experience with women from the Association of Women with Disabilities of Mato Grosso do Sul, Flávia was concerned about the invisibility and lack of accessible data and information in the area of gender and disability. The concern resulted in this book, which analyses the speeches of women with disabilities living in Campo Grande / MS, from the theme of gender violence in order to seek possibilities to implement actions to face this type of violence. The theoretical path is based on qualitative research and the corpus analysis grounded on French Discourse Analysis (FDA) studies, as well as on scholars from the Bakhtin Circle, on the analysis of texts of oral communication and the gender and violence area. The analyses presented will enable the reader to conclude that girls and women with disabilities are subject to double exclusion and vulnerability – for having a disability and for being women – by the sexist and capacitist speeches of “power” and “truth”. Therefore, it is a matter of urgency that the Brazilian authorities of power implement effective public programs and policies aimed at the specificities of those subjects.

This book focuses on two issues. First, it describes how the social significance of religion in its various facets has changed in modern societies. Second, it explains what factors and conditions have contributed to these changes. After discussing the two central concepts of the investigation, religion and modernity, the book presents the most important theories that deal with the relationship between the two. The empirical part, which constitutes the bulk of the book, begins by analysing religious change in selected countries in Western and Eastern Europe. For the sake of comparison, it then presents individual analyses of selected non-European cases (the US, South Korea), as well investigations of the global spread of Evangelicalism and Pentecostalism in Europe, the US, and in Brazil. On the basis of these selected case studies, which place as much emphasis on analysing the social, political, and economic contexts of religious changes as on capturing historical path dependencies, the book offers some general theoretical conclusions and identifies overarching patterns and determinants of religious change in modern and modernizing societies. In recent years, scholars of religion have become increasingly sceptical about the validity of secularization theory; the analyses contained in this book demonstrate, however, that tendencies of modernity such as functional differentiation, individualization, and pluralization are likely to inhibit the attractiveness and acceptance of religious affiliations, practices, and beliefs. Even Poland, Russia, the US, and South Korea, which have often been cited as prime examples of the vitality of religion in modern societies, display clear signs of religious decline.

Imagining Pakistan argues that the creation of Pakistan is a result of Muslim modernism in the Subcontinent, as it defined the struggle for identity, nationalism, and empowerment of Muslim communities. This modernist movement represented the ideals of inclusivity, equal rights, a liberal constitutional framework, and a shared sense of political community among diverse ethnic and regional groups. However, while this modernity was the ideal of Pakistan’s founders, it faced resistance from Islamists obsessed with recovering a past legacy of lost Muslim glory. A major threat to political modernism also came from the military that wanted to create a strong and secure Pakistan through ‘controlled’ democracy. Multiple interventions by the military and deviations from the foundational republican ideas left Pakistan in the rough sea of power struggles, causing institutional decay and creating space for the rise of radical Islam. Imagining Pakistan analyzes the institutional imbalance between the military and the civilian groups, the idea of the security state, and the Islamist social forces and movements that have been engaged in the politics of Islamic revival. It argues that Pakistan’s stability, security and progress will depend on pursuing the path of political modernity. Although the restoration of parliamentary democracy and the resilience of the Pakistani society are hopeful signs, resolving the critical issues that Pakistan faces today will require consolidation of democracy, better leadership, and a moderate and modernist vision of both, the state and the society.

AbstractWe wrote this book with the central goal of documenting patterns and trends of racial and ethnic segregation across communities and over time in the United States using refined methods of measurement analysis, which can sometimes be expected to change what we thought we knew from past research and at other times add more to our understanding of established patterns. In making this our goal, we produced several contributions that happily build continuity with past research and set a foundation for future research, which we can expect to come in waves each time there is a decennial census data release. First and foremost, by using measures of segregation that are free of index bias and specifically employing the separation index, a measure of evenness that can dependably signal when prototypical patterns of segregation are occurring, we were able to reanalyze and describe patterns and levels of racial and ethnic residential segregation across the United States and over time. We are not the first to describe patterns of segregation, here operationalized as the uneven distribution of two groups across neighborhood-level spatial units, across communities and over time in the United States. But we are the first to simultaneously use measures that are corrected for index bias, measure segregation of households rather than persons, and expand our analysis to not only metropolitan areas but also micropolitan areas and noncore counties. Our findings should be viewed as reliable benchmarks for descriptive analyses of racial and ethnic residential segregation across a broad range of communities moving forward and should also be taken instructively, as they demonstrate the application of the methodological changes that we recommend should be the standard for residential segregation measurement. We also use Fossett’s (2017) difference-of-means calculation of segregation indices to demonstrate new approaches for linking locational attainments to residential segregation patterns, situating segregation quantitatively as a stratification outcome. In this final chapter, we describe how this study establishes continuity with past research and sets the path for residential segregation research in the future.

AbstractThe oblique crack is a major form of damage to the rail tread surface. When it reaches a certain depth, these cracks will rapidly expand and cause transverse fractures in the rail head. Therefore, the detection of oblique cracks on rail treads is of great significance for railway safety. Based on the characteristics of rail tread detection, a rail tread oblique crack detection system has been developed and tested using the alternating current field measurement (ACFM) technique. The ACFM detection model is established using the finite element software COMSOL. It analyzes the response relationships between the induced electromagnetic field and the oblique cracks, as well as explores the influences of different scanning paths on the distortion of characteristic signals. In consideration of the rail tread's characteristics, the detection probe, scanning frame, and detector are designed, and the detection software is written to form a complete rail tread oblique crack detection system capable of detecting rail tread cracks of various lengths and depths. Simulation and experimental results demonstrate that the distortion of the characteristic signal at the center position of the oblique crack is the smallest, while the characteristic signal at the end position is the largest. The detection system can effectively detect oblique cracks as deep as 1 mm on the rail tread increases, the distortion of the crack center characteristic signal increases, and as the length of the crack increases, the distortion of the characteristic signal first increases and then decreases.

Abstract A 0.18 µm technology process was observed to generate some damage on polysilicon lines (missing polysilicon lines). This induces mainly an increase in digital scan failure rate. This was attributed to a particular fabrication cleaning tool. Improvement of the process was made. For all the material affected by the missing polysilicon line issue and to secure production, some additional production tests and burn-in were introduced. Few devices were failing digital scan test post burn-in and a very particular failure mechanism was observed. Physical failure analysis was performed on these devices, and it was related again to missing polysilicon located into the reset path of some Flip-Flops. Several improvements of the production test program were done to try to detect these devices pre-burn-in. After a final review it was concluded that the reset path failure could only be detected after burn-in.

Gas-path measurements used to assess the health condition of an engine are corrupted by noise. Generally, a data cleaning step occurs before proceeding with fault detection and isolation. Classical linear filters such as the exponentially weighted moving average filter are traditionally used for noise removal. Unfortunately, these low-pass filters distort trend shifts indicative of faults, which increases the detection delay. The present paper investigates two new approaches to non-linear filtering of time series. On one hand, the synthesis approach reconstructs the signal as a combination of elementary signals chosen from a pre-defined library. On the other hand, the analysis approach imposes a constraint on the shape of the signal (e.g., piecewise constant). Both approaches incorporate prior information about the signal in a different way, but they lead to trend filters that are very capable at noise removal while preserving at the same time sharp edges in the signal. This is highlighted through the comparison with a classical linear filter on a batch of synthetic data representative of typical engine fault profiles.

The objective includes: Assess commercially available inspection methods to validate integrity of composite repair systems. Identify applicability to inspect composite overwrap and parent metal for both onshore and sub-sea pipelines (where information is available). Identify sources of data to include other users of composite materials(aerospace/aircraft, naval/ship repairs). Identify procedures and technologies to assess inspection effectiveness and provide a gap analysis. Interface with other PRCI projects on long-term testing of composite repairs and other joint industry projects on composite repairs to improve our understanding of long term durability of repairs. Identify global experience with composite repairs; not just North America. For general wall loss, radiography or electromagnetic techniques appear to be the best candidates. Standard radiography techniques can detect changes in wall thickness over a large area. Saturated low frequency systems, e.g. SLOFEC are good for a quick rapid scan of the area of interest. Pulsed eddy current, e.g. PEC, is also available for a general survey of the underlying substrate. For pinhole leaks, the electromagnetic techniques do not have sufficient resolution to detect defects of order 20 mm (0.8 in.) diameter and less. Standard radiography techniques can detect pinhole leaks down to diameters of 3 mm (0.12 in.) or less. Tangential radiography techniques are generally good for defect sizing but there are practical limitations with chord length (i.e. beam path through the pipe wall). Ultrasonic techniques could offer a potential solution but is currently limited due to the high attenuation of the composite repair material where through the repair inspection could only detect large diameter defects greater than 25 mm (1 in.) diameter on thin repairs less than 5 mm (0.2 in.). Detecting pin hole defects by applying the ultrasound along the axial direction of the substrate, effectively skipping the ultrasound under the repair, showed more promise. For delamination or debonding of the interface between the composite laminate and the steel substrate, laser shearography and microwave inspection appear to offer the best solution. Currently there is no single inspection technique that can be applied with confidence to the inspection of interfacial delaminations. Further developments are on-going to provide a solution to this challenging inspection problem. Acoustic emission is able to give an overall picture of the damage within the composite under live loads. It can be used as a QA tool to test the integrity of the repair. However, it is difficult to interpret the signals to gain any quantitative information about a particular defect.

The National Park Service collects water-quality samples on a rotating basis at three fixed water-quality stations in Bryce Canyon National Park (NP): Sheep Creek, Yellow Creek, and Mossy Cave Spring. Data collection began at Sheep Creek and Yellow Creek in November 2005 and at Mossy Cave in July 2008. Data on in-situ parameters, fecal-coliform samples, major ions, and nutrients are collected monthly, while trace elements are sampled quarterly. This report analyzes data from the beginning of the period of record for each station through water year 2021 to test for trends over time. Concentrations are also compared to relevant water-quality standards for the State of Utah. Overall, water quality at the park’s monitoring stations continues to be excellent, and park managers have been successful in their goal of maintaining these systems in unimpaired condition. Infrequent but continued Escherichia coli exceedances from trespass livestock at Sheep and Yellow creeks support the need for regular fence maintenance along the park boundary. High-quality conditions may qualify all three sites as Category 1 waters, the highest level of anti-degradation protection provided by the State of Utah. Minimum and maximum air temperatures at the park have increased, while precipitation remains highly variable. Increasing air temperatures have led to increasing water temperatures in Sheep and Yellow creeks. Sheep Creek also had a decrease in flow across several quantiles from 2006 to 2021, while higher flows decreased at Yellow Creek in the same period. Surface flows in these two creeks are likely to be increasingly affected by higher evapotranspiration due to warming air temperatures and possibly decreasing snowmelt runoff as the climate changes. The influx of ancient groundwater in both creek drainages helps sustain base flows at the sites. Mossy Cave Spring, which is sampled close to the spring emergence point, showed less of a climate signal than Sheep and Yellow creeks. In our record, the spring shows a modest increase in discharge, including higher flows at higher air temperatures. An uptick in visitation to Water Canyon and the Mossy Cave Trail has so far not been reflected by changes in water quality. There are additional statistical trends in water-quality parameters at all three sites. However, most of these trends are quite small and are likely ecologically negligible. Some statistical trends may be the result of instrument changes and improvements in quality assurance and quality control over time in both the field sampling effort and the laboratory analyses. Long-term monitoring of water-quality stations at Bryce Canyon NP suggests relatively stable aquatic systems that benefit from protection within the park. To maintain these unimpaired conditions into the future, park managers could consider: Regular fence checks and maintenance along active grazing allotments at the park boundary to protect riparian areas and aquatic systems from trespass livestock. Developing a springs-monitoring program to track changes in springflow at spring emergences to better understand bedrock-aquifer water supplies. These data would also help quantify springflow for use in water-rights hearings. Supporting hydrogeologic investigations to map the extent and flow paths of groundwater aquifers. Working with the State of Utah to develop groundwater-protection zones to protect groundwater aquifers from developments that would affect springs in the park. Prioritizing watershed management with proactive fire risk-reduction practices. Explicitly including watershed protection as a goal in plans for fire management and suppression. Using additional data and analyses to better understand the drivers of trends in water quality and their ecological significance. These could include higher-frequency data to better understand relationships between groundwater, precipitation, and surface flows at the sites. These could also include watershed metrics...

1.1 Macroeconomic summary Economic recovery has consistently outperformed the technical staff’s expectations following a steep decline in activity in the second quarter of 2020. At the same time, total and core inflation rates have fallen and remain at low levels, suggesting that a significant element of the reactivation of Colombia’s economy has been related to recovery in potential GDP. This would support the technical staff’s diagnosis of weak aggregate demand and ample excess capacity. The most recently available data on 2020 growth suggests a contraction in economic activity of 6.8%, lower than estimates from January’s Monetary Policy Report (-7.2%). High-frequency indicators suggest that economic performance was significantly more dynamic than expected in January, despite mobility restrictions and quarantine measures. This has also come amid declines in total and core inflation, the latter of which was below January projections if controlling for certain relative price changes. This suggests that the unexpected strength of recent growth contains elements of demand, and that excess capacity, while significant, could be lower than previously estimated. Nevertheless, uncertainty over the measurement of excess capacity continues to be unusually high and marked both by variations in the way different economic sectors and spending components have been affected by the pandemic, and by uneven price behavior. The size of excess capacity, and in particular the evolution of the pandemic in forthcoming quarters, constitute substantial risks to the macroeconomic forecast presented in this report. Despite the unexpected strength of the recovery, the technical staff continues to project ample excess capacity that is expected to remain on the forecast horizon, alongside core inflation that will likely remain below the target. Domestic demand remains below 2019 levels amid unusually significant uncertainty over the size of excess capacity in the economy. High national unemployment (14.6% for February 2021) reflects a loose labor market, while observed total and core inflation continue to be below 2%. Inflationary pressures from the exchange rate are expected to continue to be low, with relatively little pass-through on inflation. This would be compatible with a negative output gap. Excess productive capacity and the expectation of core inflation below the 3% target on the forecast horizon provide a basis for an expansive monetary policy posture. The technical staff’s assessment of certain shocks and their expected effects on the economy, as well as the presence of several sources of uncertainty and related assumptions about their potential macroeconomic impacts, remain a feature of this report. The coronavirus pandemic, in particular, continues to affect the public health environment, and the reopening of Colombia’s economy remains incomplete. The technical staff’s assessment is that the COVID-19 shock has affected both aggregate demand and supply, but that the impact on demand has been deeper and more persistent. Given this persistence, the central forecast accounts for a gradual tightening of the output gap in the absence of new waves of contagion, and as vaccination campaigns progress. The central forecast continues to include an expected increase of total and core inflation rates in the second quarter of 2021, alongside the lapse of the temporary price relief measures put in place in 2020. Additional COVID-19 outbreaks (of uncertain duration and intensity) represent a significant risk factor that could affect these projections. Additionally, the forecast continues to include an upward trend in sovereign risk premiums, reflected by higher levels of public debt that in the wake of the pandemic are likely to persist on the forecast horizon, even in the context of a fiscal adjustment. At the same time, the projection accounts for the shortterm effects on private domestic demand from a fiscal adjustment along the lines of the one currently being proposed by the national government. This would be compatible with a gradual recovery of private domestic demand in 2022. The size and characteristics of the fiscal adjustment that is ultimately implemented, as well as the corresponding market response, represent another source of forecast uncertainty. Newly available information offers evidence of the potential for significant changes to the macroeconomic scenario, though without altering the general diagnosis described above. The most recent data on inflation, growth, fiscal policy, and international financial conditions suggests a more dynamic economy than previously expected. However, a third wave of the pandemic has delayed the re-opening of Colombia’s economy and brought with it a deceleration in economic activity. Detailed descriptions of these considerations and subsequent changes to the macroeconomic forecast are presented below. The expected annual decline in GDP (-0.3%) in the first quarter of 2021 appears to have been less pronounced than projected in January (-4.8%). Partial closures in January to address a second wave of COVID-19 appear to have had a less significant negative impact on the economy than previously estimated. This is reflected in figures related to mobility, energy demand, industry and retail sales, foreign trade, commercial transactions from selected banks, and the national statistics agency’s (DANE) economic tracking indicator (ISE). Output is now expected to have declined annually in the first quarter by 0.3%. Private consumption likely continued to recover, registering levels somewhat above those from the previous year, while public consumption likely increased significantly. While a recovery in investment in both housing and in other buildings and structures is expected, overall investment levels in this case likely continued to be low, and gross fixed capital formation is expected to continue to show significant annual declines. Imports likely recovered to again outpace exports, though both are expected to register significant annual declines. Economic activity that outpaced projections, an increase in oil prices and other export products, and an expected increase in public spending this year account for the upward revision to the 2021 growth forecast (from 4.6% with a range between 2% and 6% in January, to 6.0% with a range between 3% and 7% in April). As a result, the output gap is expected to be smaller and to tighten more rapidly than projected in the previous report, though it is still expected to remain in negative territory on the forecast horizon. Wide forecast intervals reflect the fact that the future evolution of the COVID-19 pandemic remains a significant source of uncertainty on these projections. The delay in the recovery of economic activity as a result of the resurgence of COVID-19 in the first quarter appears to have been less significant than projected in the January report. The central forecast scenario expects this improved performance to continue in 2021 alongside increased consumer and business confidence. Low real interest rates and an active credit supply would also support this dynamic, and the overall conditions would be expected to spur a recovery in consumption and investment. Increased growth in public spending and public works based on the national government’s spending plan (Plan Financiero del Gobierno) are other factors to consider. Additionally, an expected recovery in global demand and higher projected prices for oil and coffee would further contribute to improved external revenues and would favor investment, in particular in the oil sector. Given the above, the technical staff’s 2021 growth forecast has been revised upward from 4.6% in January (range from 2% to 6%) to 6.0% in April (range from 3% to 7%). These projections account for the potential for the third wave of COVID-19 to have a larger and more persistent effect on the economy than the previous wave, while also supposing that there will not be any additional significant waves of the pandemic and that mobility restrictions will be relaxed as a result. Economic growth in 2022 is expected to be 3%, with a range between 1% and 5%. This figure would be lower than projected in the January report (3.6% with a range between 2% and 6%), due to a higher base of comparison given the upward revision to expected GDP in 2021. This forecast also takes into account the likely effects on private demand of a fiscal adjustment of the size currently being proposed by the national government, and which would come into effect in 2022. Excess in productive capacity is now expected to be lower than estimated in January but continues to be significant and affected by high levels of uncertainty, as reflected in the wide forecast intervals. The possibility of new waves of the virus (of uncertain intensity and duration) represents a significant downward risk to projected GDP growth, and is signaled by the lower limits of the ranges provided in this report. Inflation (1.51%) and inflation excluding food and regulated items (0.94%) declined in March compared to December, continuing below the 3% target. The decline in inflation in this period was below projections, explained in large part by unanticipated increases in the costs of certain foods (3.92%) and regulated items (1.52%). An increase in international food and shipping prices, increased foreign demand for beef, and specific upward pressures on perishable food supplies appear to explain a lower-than-expected deceleration in the consumer price index (CPI) for foods. An unexpected increase in regulated items prices came amid unanticipated increases in international fuel prices, on some utilities rates, and for regulated education prices. The decline in annual inflation excluding food and regulated items between December and March was in line with projections from January, though this included downward pressure from a significant reduction in telecommunications rates due to the imminent entry of a new operator. When controlling for the effects of this relative price change, inflation excluding food and regulated items exceeds levels forecast in the previous report. Within this indicator of core inflation, the CPI for goods (1.05%) accelerated due to a reversion of the effects of the VAT-free day in November, which was largely accounted for in February, and possibly by the transmission of a recent depreciation of the peso on domestic prices for certain items (electric and household appliances). For their part, services prices decelerated and showed the lowest rate of annual growth (0.89%) among the large consumer baskets in the CPI. Within the services basket, the annual change in rental prices continued to decline, while those services that continue to experience the most significant restrictions on returning to normal operations (tourism, cinemas, nightlife, etc.) continued to register significant price declines. As previously mentioned, telephone rates also fell significantly due to increased competition in the market. Total inflation is expected to continue to be affected by ample excesses in productive capacity for the remainder of 2021 and 2022, though less so than projected in January. As a result, convergence to the inflation target is now expected to be somewhat faster than estimated in the previous report, assuming the absence of significant additional outbreaks of COVID-19. The technical staff’s year-end inflation projections for 2021 and 2022 have increased, suggesting figures around 3% due largely to variation in food and regulated items prices. The projection for inflation excluding food and regulated items also increased, but remains below 3%. Price relief measures on indirect taxes implemented in 2020 are expected to lapse in the second quarter of 2021, generating a one-off effect on prices and temporarily affecting inflation excluding food and regulated items. However, indexation to low levels of past inflation, weak demand, and ample excess productive capacity are expected to keep core inflation below the target, near 2.3% at the end of 2021 (previously 2.1%). The reversion in 2021 of the effects of some price relief measures on utility rates from 2020 should lead to an increase in the CPI for regulated items in the second half of this year. Annual price changes are now expected to be higher than estimated in the January report due to an increased expected path for fuel prices and unanticipated increases in regulated education prices. The projection for the CPI for foods has increased compared to the previous report, taking into account certain factors that were not anticipated in January (a less favorable agricultural cycle, increased pressure from international prices, and transport costs). Given the above, year-end annual inflation for 2021 and 2022 is now expected to be 3% and 2.8%, respectively, which would be above projections from January (2.3% and 2,7%). For its part, expected inflation based on analyst surveys suggests year-end inflation in 2021 and 2022 of 2.8% and 3.1%, respectively. There remains significant uncertainty surrounding the inflation forecasts included in this report due to several factors: 1) the evolution of the pandemic; 2) the difficulty in evaluating the size and persistence of excess productive capacity; 3) the timing and manner in which price relief measures will lapse; and 4) the future behavior of food prices. Projected 2021 growth in foreign demand (4.4% to 5.2%) and the supposed average oil price (USD 53 to USD 61 per Brent benchmark barrel) were both revised upward. An increase in long-term international interest rates has been reflected in a depreciation of the peso and could result in relatively tighter external financial conditions for emerging market economies, including Colombia. Average growth among Colombia’s trade partners was greater than expected in the fourth quarter of 2020. This, together with a sizable fiscal stimulus approved in the United States and the onset of a massive global vaccination campaign, largely explains the projected increase in foreign demand growth in 2021. The resilience of the goods market in the face of global crisis and an expected normalization in international trade are additional factors. These considerations and the expected continuation of a gradual reduction of mobility restrictions abroad suggest that Colombia’s trade partners could grow on average by 5.2% in 2021 and around 3.4% in 2022. The improved prospects for global economic growth have led to an increase in current and expected oil prices. Production interruptions due to a heavy winter, reduced inventories, and increased supply restrictions instituted by producing countries have also contributed to the increase. Meanwhile, market forecasts and recent Federal Reserve pronouncements suggest that the benchmark interest rate in the U.S. will remain stable for the next two years. Nevertheless, a significant increase in public spending in the country has fostered expectations for greater growth and inflation, as well as increased uncertainty over the moment in which a normalization of monetary policy might begin. This has been reflected in an increase in long-term interest rates. In this context, emerging market economies in the region, including Colombia, have registered increases in sovereign risk premiums and long-term domestic interest rates, and a depreciation of local currencies against the dollar. Recent outbreaks of COVID-19 in several of these economies; limits on vaccine supply and the slow pace of immunization campaigns in some countries; a significant increase in public debt; and tensions between the United States and China, among other factors, all add to a high level of uncertainty surrounding interest rate spreads, external financing conditions, and the future performance of risk premiums. The impact that this environment could have on the exchange rate and on domestic financing conditions represent risks to the macroeconomic and monetary policy forecasts. Domestic financial conditions continue to favor recovery in economic activity. The transmission of reductions to the policy interest rate on credit rates has been significant. The banking portfolio continues to recover amid circumstances that have affected both the supply and demand for loans, and in which some credit risks have materialized. Preferential and ordinary commercial interest rates have fallen to a similar degree as the benchmark interest rate. As is generally the case, this transmission has come at a slower pace for consumer credit rates, and has been further delayed in the case of mortgage rates. Commercial credit levels stabilized above pre-pandemic levels in March, following an increase resulting from significant liquidity requirements for businesses in the second quarter of 2020. The consumer credit portfolio continued to recover and has now surpassed February 2020 levels, though overall growth in the portfolio remains low. At the same time, portfolio projections and default indicators have increased, and credit establishment earnings have come down. Despite this, credit disbursements continue to recover and solvency indicators remain well above regulatory minimums. 1.2 Monetary policy decision In its meetings in March and April the BDBR left the benchmark interest rate unchanged at 1.75%.

This P-Analysis report highlights the impact of COVID-19 pandemic lockdowns on productivity and economic growth in Pakistan. Owing to the government’s fiscal and monetary measures, the economy is on the right path to recovery. However, the signs of recovery do not ensure fully revitalized long-term productivity. Structural weaknesses steming from selective subsidies, high tariffs, outdated technology, an unskilled workforce, and low R&amp;D spending are areas to be addressed in long-term productivity policies.