Miracle-dz/UniFAR-FTUs huggingface dataset:
Deterministic compressed sensing

The central goal of compressed sensing is to capture attributes of a signal using very few measurements. The initial publications by Donoho and by Candes and Tao have been followed by applications to image compression, data streaming, medical signal processing, digital communication and many others. The emphasis has been on random sensing but the limitations of this framework include performance guarantees, storage requirements, and computational cost. This thesis will describe two deterministic alternatives. The first alternative is based on expander graphs. We first show how expander graphs are appropriate for compressed sensing in terms of providing explicit and efficient sensing matrices as well as simple and efficient recovery algorithms. We show that by reformulating signal reconstruction as a zero-sum game we can efficiently recover any sparse vector. We provide a saddle-point reformulation of the expander-based sparse approximation problem, and propose an efficient expander-based sparse approximation algorithm, called the GAME algorithm. We show that the restricted isometry property of expander matrices in the e1-norm ensures that the GAME algorithm always recovers a sparse approximation to the optimal solution with an e1/e 1 data-domain approximation guarantee. We also demonstrate resilience to Poisson noise. The Poisson noise model is appropriate for a variety of applications, including low-light imaging and digital streaming, where the signal-independent and/or bounded noise models used in the compressed sensing literature are no longer applicable. We develop a novel sensing paradigm based on expander graphs and propose a MAP algorithm for recovering sparse or compressible signals from Poisson observations. We support our results with experimental demonstrations of reconstructing average packet arrival rates and instantaneous packet counts at a router in a communication network, where the arrivals of packets in each flow follow a Poisson process. The second alternative is based on error correcting codes. We show that deterministic sensing matrices based on second order Reed Muller codes optimize average case performance. We also describe a very simple algorithm, one-step thresholding, that succeeds in average case model selection and sparse approximation, where more sophisticated algorithms, developed in the context of random sensing, fail completely. Finally, we provide an algorithmic framework for structured sparse recovery, where some extra prior knowledge about the sparse vector is also available. Our algorithm, called Nesterov Iterative Hard-Thresholding (NIHT) uses the gradient information in the convex data error objective to navigate over the non-convex set of structured sparse signals. Experiments show however that NIHT can empirically outperform e1-minimization and other state-of-the-art convex optimization-based algorithms in sparse recovery.
Effects of task design on EFL learners' written language performance

Task structure as a task characteristic is believed to have a considerable effect on task performance in terms of accuracy, fluency and complexity. Studies in the literature focused on investigating task structure impact on oral out-put; however, this study examines how written task performance is affected by task structure. Thirty two EFL learners were selected for data collection. Each participant, then, narrated two tasks which differed with regard to their inherent structure (tight vs. loose). Collected data were coded and checked for measuring their accuracy, fluency and complexity. Findings of the statistical analysis revealed that structured tasks produced more fluent and complex performances while accuracy remained unaffected. Results have practical implications for language teaching, research and syllabus design.
Design of Wireless Communication Networks for Cyber-Physical Systems with Application to Smart Grid

Cyber-Physical Systems (CPS) are the next generation of engineered systems in which computing, communication, and control technologies are tightly integrated. On one hand, CPS are generally large with components spatially distributed in physical world that has lots of dynamics; on the other hand, CPS are connected, and must be robust and responsive. Smart electric grid, smart transportation system are examples of emerging CPS that have significant and far-reaching impact on our daily life. In this dissertation, we design wireless communication networks for CPS. To make CPS robust and responsive, it is critical to have a communication subsystem that is reliable, adaptive, and scalable. Our design uses a layered structure, which includes physical layer, multiple access layer, network layer, and application layer. Emphases are placed on multiple access and network layer. At multiple access layer, we have designed three approaches, namely compressed multiple access, sample-contention multiple access, and prioritized multiple access, for reliable and selective multiple access. At network layer, we focus on the problem of creating reliable route, with service interruption anticipated. We propose two methods: the first method is a centralized one that creates backup path around zones posing high interruption risk; the other method is a distributed one that utilizes Ant Colony Optimization (ACO) and positive feedback, and is able to update multipath dynamically. Applications are treated as subscribers to the data service provided by the communication system. Their data quality requirements and Quality of Service (QoS) feedback are incorporated into cross-layer optimization in our design. We have evaluated our design
MODELO CINÉTICO DEL SECADO DE LA PULPA DE MANGO

El proposito de este trabajo fue encontrar un modelo que permitiera predecir el tiempo de secado de la pulpa de mango (Mangifera indica) con diferentes condiciones de temperatura. Se construyo un secador de laboratorio en el que se llevaron a cabo pruebas de secado a temperaturas de 55 oC, 60 oC y 65 oC, con una velocidad de aire constante de 2,0 m/s y una humedad relativa controlada de 50%. Se presenta un procedimiento sencillo que convierte el modelo de GAB en una ecuacion polinomial de segundo orden. Igualmente, se muestra una manera simple aplicable a procesos similares de secado para establecer su cinetica a partir de modelos simplificados de la ecuacion clasica de Fick. Abstract: The aim of this work was to find a model which allows predicting the drying time of mango (Mangifera indica) pulp at different temperature conditions. A laboratory dryer was built in which several drying probes at 55 oC, 60 oC, and 65 oC took place, with a constant air velocity of 2,0 m/s and a 50% controlled relative humidity. A simple procedure to convert GAB model to a second order polynomial equation is shown. Also, it is shown a simple manner to establish process drying kinetics that could be applied to similar processes from simplified models of the classical Fick´s equation
A comparative study of three instructional modalities in a computer programming course: traditional instruction, web-based instruction, and online instruction

This study is a quasi-experimental design to examine students' performance in integrating the web in different aspects of teaching and learning in an introductory programming course. This course is an introduction to problem-solving methods and algorithm development using a higher-level programming language (C++). This empirical, exploratory study examined the academic performance, motivation, satisfaction and course completion rate of students using three instructional modalities: (1) traditional face-to-face, (2) web-assisted, and (3) online. Participants were primarily entering first year college students attending an Historically Black College and University (HBCU) majoring in computer science. Data collected included scores on the departmental computer placement test, the proficiency examination, two multiple-choice examinations, three programming assignments, the Intrinsic Motivation Inventory (IMI), the course evaluation form, and the Motivated Strategies Learning Questionnaire (MSLQ). This study supports the body of research studies that have concluded that online instruction is as effective as traditional face-to-face instruction. This study revealed that the instructional modality did not affect student motivation, self-regulation completion rate, and academic performance on the end of semester proficiency examination. However, in this study face-to-face, web-assisted, and online instructional modalities were equally effective for teaching computer programming.
Bicycle Detection and Operational Concept at Signalized Intersections Phase 2

California requires that the road network provide equal service to bicyclists as it does to motorists. This project extends previous studies of bicyclist signal timing to a wider range of intersections and traffic signal control scenarios. A portable video data acquisition system was used to collect data about bicyclist crossing times and speeds at five new intersections to complement data previously collected at two intersections, providing considerable geographical diversity, diversity of bicycling population, and diversity of intersection size and geometry. Data about bicyclist crossing times show that factors to be accounted for in selection of signal timing include street width, grades, demographics, and trip purpose. Timing recommendations in Caltrans TOPD 09-06 appear to be generally suitable for serving the needs of 85% of the bicycling population. Those signal timing recommendations would require increases in the minimum clearance intervals for wide intersections in California. Simulation shows that the effects on travel speed and delays were negligible in low and moderate density conditions.
Crome : un cadre de programmation par objets structurés en contextes

L'approche orientee objet offre a la base des qualites connues et largement exploitees pour le developpement d'environnements logiciels complexes. Nous nous interessons ici aux logiciels centres sur un referentiel d'objets intervenant dans des contextes applicatifs, ou fonctionnels, multiples. On rencontre de tels environnements dans les activites de conception ou d'ingenierie assistee par ordinateur. Dans une approche exclusivement orientee objet il est souvent difficile de concevoir et de circonscrire les fonctions transversales de tels systemes. Cette these etudie leur double decomposition, orthogonale, en objets et en fonctions pour tirer profit conjointement de leurs qualites structurantes respectives. L'analyse de l'existant montre que ces deux axes de structuration ont souvent ete etudies separement. Sous l'angle des objets nous retenons les techniques de programmation par points de vue. Elles se situent cependant au niveau granulaire trop fin de l'objet. Sous l'angle des fonctions plusieurs etudes montrent l'importance d'identifier cette dimension. Cependant les techniques employees ne font pas le lien entre la structuration en fonctions du systeme et la structuration interne des objets y prenant part. Nous proposons alors CROME, un cadre de programmation par objets structures en contextes fonctionnels, decrits par des plans. Un plan de base introduit la structure du referentiel sous la forme d'une hierarchie de classes. Chaque contexte fonctionnel est decrit par un plan qui adapte les objets du referentiel pour ses besoins. Cette adaptation s'appuie sur une technique d'heritage modulaire entre plans, la programmation de communications circonscrites aux contextes, et la programmation inter-contextes au sein des objets. CROME a ete meta-programme dans le langage ROME, profitant de sa representation multiple par points de vue. Le cadre propose se veut general et nous montrons son application a l'environnement Smalltalk et des experiences de developpement.
RAPT, A Language for Describing Assemblies

A reflector, for reflecting generally all wavelengths of radiation of visible light from a multilayer interference reflecting coating for generally concentrated projection of the visible light and for absorbing substantially all wavelengths of radiation of heat, is provided for by a metallic substrate having formed thereon, between it and the multilayer interference reflecting coating, an antireflection coating having a continuously graded refractive index for transmission therethrough of wavelengths of heat radiation for absorption into the metallic substrate.
Theoretical and Practical Considerations in the Design of Web-Based Instruction

INTRODUCTION The intended audiences for this chapter are (a) individuals who design and develop Web-based instruction in any setting (i.e., university faculty, instructional developers in medical, business and government settings), and (b) graduate students in the fields of instructional design, educational technology, and educational psychology. The purposes of this chapter are to: • describe three unique features of the Web environment relevant to instruction: structure, media, and communication capabilities; • explore the role of epistemology in the design of instruction: relationships of epistemology to cognitive learning theories, Web technologies and practice; • examine five factors that influence the design of Web-based instruction: theoretical orientation, learning goals, content, learner characteristics, and technological capabilities; • recommend ten issues for Web course developers to consider as they design Webbased instruction; • discuss four factors that will affect the future of Web-based instruction: efficacy studies, technological advances, pressures of competition and cost containment, and professional responses to market influences.
Specialized Caches To Improve Data Access Performance

High performance processor organizations place large demands on the data memory hierarchy. The data bandwidth requirements of a processor can be a serious performance constraint. As a result, cache memory is a very important element in the implementation of a high performance computer. Caching a subset of main memory in faster memory provides the processor with high bandwidth and low latency data. The utility of caching is determined by the cache size, organization, and speed. The focus of this dissertation is to improve the performance of a data cache by the addition of small specialized caches. By analyzing the spatial and temporal locality in the data reference stream at various points in the data memory hierarchy, we have developed a mixture of specialized caches to improve the data memory hierarchy. We have developed and analyzed write caches, tag caches, subword caches, fetch caches, and a two-level windowed register le. Each specialized cache reduces the bandwidth and/or latency demands on the data memory hierarchy. Write caches reduce write-through cache tra c. Tag caches reduce tag checks to write-back caches. Subword caches enhance the bene t of removing the subword hardware from the primary cache access path. Fetch caches reduce read latency or increase read bandwidth. A two-level windowed register le provides large capacity without impacting cycle time. Thus, a mixture of specialized caches has been developed to improve the data memory hierarchy. iv Acknowledgements Earning a Ph.D. is a grueling process, without the love and support of others it would be impossible. For providing me with the love and support I needed, I thank my wife Ireena A. Erteza, my parents, my relatives, and my friends. Ideas and analysis are only part of the Ph.D. process, being able to present them to others is crucial. The feedback of others is very important, therefore I thank Ireena A. Erteza and William Lynch for reading drafts of my technical reports and papers. Another important element in earning a Ph.D. is having facilities and nancial support. I thank my advisor Michael J. Flynn for providing a good work environment, and I thank NASA and IDA for providing funds for the projects I was involved with. v
The Pictorial World of the Child

The Pictorial World of the Child is a valuable resource for anyone working with children. It takes the mind of the reader away from reality and into the colourful world of childhood fantasies where everything is possible, and even the most bizarre things seem to be natural. The author, Maureen Cox, well known from her previous publications on artistic development, approaches the topic very seriously. She emphasizes that childhood drawings are not just scribbles, but real artwork and need to be recognized as such. To support her position she borrows these words from Picasso: “Previously I used to draw like Rafael, but it’s taken my entire lifetime to learn to draw like children do” (page 149).
The MetaForma Language: A DSL to Program the ATRON Self-Reconfigurable Robot

Self-reconfigurable modular robots are mechatronic devices that have the capability to modify their own shape. They have a promising potential as a result of being able to solve a wider range of problems. However, programming self-reconfigurable robots is in general a difficult task. General-purpose languages like ANSI-C or Java provide only general abstractions that do not facilitate tackling difficult issues such as distribution, unreliable hardware, and dynamically evolving communication topology. We believe that a domain-specific language is needed to be able to program robot behavior on a higher, more productive level. Existing DSLs and control approaches have been developed in the past, but were designed to solve problems specific to certain scenarios. In this work, a domain analysis is used to identify and define concepts in existing approaches. Based on this, a prototype for a new DSL is implemented in the language-workbench Spoofax. The prototype is called MetaForma and comprises a compiler with Eclipse IDE support and a static runtime-system. The runtime system acts as an abstraction on top of the ATRON robot and the USSR robot simulator. The USSR simulator is used to conduct experiments on generated Java code that simulates the behavior of the ATRON robot and justifies claims for robustness. The contribution of MetaForma is twofold. First, it supports shape-transformations and locomotion of small ATRON ensembles. Second, it supports locomotion methods for large-scale ATRON ensembles, that were published in earlier work but not implemented in a language before. Although not all solutions are yet implemented in the MetaForma runtime-system, and it currently only runs in simulation, we believe that MetaForma is a powerful DSL solution for the ATRON robot.
WiFi Roaming along urban routes

The growing need for Internet access is a reality. In an urban environment is desirable an uninterrupted connection along a given route, to make possible the use of applications like browsing, navigation or VoIP, using preferentially WiFi since it is cheaper than cellular technologies. To accomplish this is essential to analyze in detail the steps involved in the handoff of one WiFi access point to another in order to understand the delays introduced in each one of these steps. The Future Cities project has currently a sensing infrastructure installed in Porto which gives, among other information, data about WiFi access points in the city and their coverage areas, and this is the basis to the design of a solution for fast WiFi handoffs. This report presents the state of the art solutions in WiFi roaming, divided by the stages that they aim to improve. Analyzing this and considering the existing public networks in the city of Porto an architecture is proposed that aims at providing fast handoffs along an urban route controled by the GPS location of the device. In particular the solution improves the scanning phase with single channel scans and the DHCP process with a decrease of retransmission delays and a message exchange optimization. The results show gains of more than 90% for the DHCP process, for three of the four networks in study. Regarding the scanning phase, it is possible to reduce its delay to only about 50 ms, which corresponds to gains of about 90%. These improvements, combined with an algorithm that controls the handoffs in the device, decrease the time without connectivity along an urban route in about 80% and the packet loss rate in more than 70%, because there is less time wasted in these processes. Moreover, the modifications can be easily adopted in further Android versions drastically reducing the time an user takes to connect to a network, and thus providing a better user experience.
New Fingerprint Minutiae Extraction Using Ridge Flux Analysis

This paper presents a new fingerprint minutiae extraction approach that is based on the analysis of the ridge flux distribution. The considerable processing time taken by the conventional approaches, most of which use the ridge thinning process with a rather large calculation time, is a problem that has recently attracted increased attention. We observe that the features of a ridge curve are very similar to those of a vector flux such as a line of electric force or a line of magnetic force. In the proposed approach, vector flux analysis is applied to detect minutiae without using the ridge thinning process in order to reduce the computation time. The experimental results show that the proposed approach can achieve a reduction in calculation time, while achieving the same success detection rate as that of the conventional approaches.
Graph- based segmentation of skeletal striated muscles in NMR images

Segmentation of magnetic resonance images (MRI) of skeletal striated muscles is of crucial interest when studying myopathies. Diseases understanding, therapeutic followups of patients, etc. rely on discriminating the muscles in MRI anatomical images. However, delineating the muscle contours manually is an extremely long and tedious task, and thus often a bottleneck in clinical research. Typical automatic segmentation methods rely on finding discriminative visual properties between objects of interest, accurate contour detection or clinically interesting anatomical points. Skeletal muscles show none of these features in MRI, making automatic segmentation a challenging problem. In spite of recent advances on segmentation methods, their application in clinical settings is difficult, and most of the times, manual segmentation and correction is still the only option. In this thesis, we propose several approaches for segmenting skeletal muscles automatically in MRI, all related to the popular graph-based Random Walker (RW) segmentation algorithm. The strength of the RW method relies on its robustness in the case of weak contours and its fast and global optimization. Originally, the RW algorithm was developed for interactive segmentation: the user had to pre-segment small regions of the image – called seeds – before running the algorithm which would then complete the segmentation. Our first contribution is a method for automatically generating and labeling all the appropriate seeds, based on a Markov Random Fields formulation integrating prior knowledge of the relative positions, and prior detection of contours between pairs of seeds. A second contribution amounts to incorporating prior knowledge of the shape directly into the RW framework. Such formulation retains the probabilistic interpretation of the RW algorithm and thus allows to compute the segmentation by solving a large but simple sparse linear system, like in the original method. In a third contribution, we propose to develop a learning framework to estimate the optimal set of parameters for balancing the contrast term of the RW algorithm and the different existing prior models. The main challenge we face is that the training samples are not fully supervised. Specifically, they provide a hard segmentation of the medical images, instead of the optimal probabilistic segmentation, which corresponds to the desired output of the RW algorithm. We overcome this challenge by treating the optimal probabilistic segmentation as a latent variable. This allows us to employ the latent Support Vector Machine (latent SVM) formulation for parameter estimation. All proposed methods are tested and validated on real clinical datasets of MRI volumes of lower limbs.