Arduino Verkstad AB, the Swedish branch of Arduino, has developed a prototype that demonstrates a smart transducer network with a self-configurable communication protocol. The protocol is called I2C+, since it is based upon I2C. One of the possible areas of application is the EU funded PELARS project, where Arduino Verkstad is responsible for creating educational tools. Within the PELARS project, a maximum number of transducer modules is expected to be 20 modules, connected at the same time.The aim of this thesis was to create a testing tool and a test suite for the prototype system, which later could be used and also further developed by engineers at Arduino Verkstad, during the development of the final product. Though the testing tool was primarily needed for this particular system, it was considered desirable if it could be reused for similar projects as well.It was relevant to create the testing tool and the test suite in order to analyse the validity of the I2C+ protocol, which might become Arduino's future standard in connectivity between smart transducers. The performance of the I2C+ protocol also affects the implementation of the smart transducer system within the PELARS project.This work has been guided by a specification of requirements and also by a systematic top-down approach of solving several subproblems. A testing tool and a test suite was created, which serves as a proof-of-concept. The testing tool has a modular design, which makes the solution reusable for other purposes. The testing tool and the test suite was validated by using Arduino's prototype as a test object. Although only 10 transducer modules was used during these tests, the results showed that the prototype does not perform well for a growing number of modules. Therefore, improvement of the system and further testing is advised.

Dans cette thèse, nous explorons l'utilisation des dérivées Gaussiennes multi-échelles comme représentation initiale pour la détection, la reconnaissance et la classification des visages humains dans des images. Nous montrons qu'un algorithme rapide, $O(N)$, de construction d'une pyramide binomiale peut être utilisé pour extraire des dérivées Gaussiennes avec une réponse impulsionnelle identique à un facteur d'échelle $sqrt{2}$>. Nous montrons ensuite qu'un vecteur composé de ces dérivées à différentes échelles et à différents ordres en chaque pixel peut être utilisé comme base pour les algorithmes de détection, de classification et de reconnaissance lesquels atteignent ou dépassent les performances de l'état de l'art avec un coût de calcul réduit. De plus l'utilisation de coefficients entiers, avec une complexité de calcul et des exigences mémoires en $O(N)$ font qu'une telle approche est appropriée pour des applications temps réel embarquées sur des systèmes mobiles. Nous testons cette représentation en utilisant trois problèmes classiques d'analyse d'images faciales : détection de visages, reconnaissance de visages et estimation de l'âge. Pour la détection de visages, nous examinons les dérivées Gaussiennes multi-échelles comme une alternative aux ondelettes de Haar pour une utilisation dans la construction d'une cascade de classifieurs linéaires appris avec l'algorithme Adaboost, popularisé par Viola and Jones. Nous montrons que la représentation pyramidale peut être utilisée pour optimiser le processus de détection en adaptant la position des dérivées dans la cascade. Dans ces experiences nous sommes capables de montrer que nous pouvons obtenir des niveaux de performances de détection similaires (mesurés par des courbes ROC) avec une réduction importante du coût de calcul. Pour la reconnaissance de visages et l'estimation de l'âge, nous montrons que les dérivées Gaussiennes multi-échelles peuvent être utilisées pour calculer une représentation tensorielle qui conserve l'information faciale la plus importante. Nous montrons que combinée à l'Analyse Multilinéaire en Composantes Principales et à la méthode Kernel Discriminative Common Vectors (KDCV), cette représentation tensorielle peut mener à un algorithme qui est similaire aux techniques concurrentes pour la reconnaissance de visages avec un coût de calcul réduit. Pour l'estimation de l'âge à partir d'images faciales, nous montrons que notre représentation tensorielle utilisant les dérivées de Gaussiennes multi-échelles peut être utilisée avec une machine à vecteur de pertinence pour fournir une estimation de l'âge avec des niveaux de performances similaires aux méthodes de l'état de l'art. / In this thesis, we propose to modelize facial images using Gaussian Derivatives computed with a Half-Octave Gaussian Pyramid. In this scope, Gaussian derivatives have shown a high versatility in object recognition and image analysis, nevertheless there is not a considerable number of proposed aproaches in the state-of-the-art that uses Gaussian derivatives for extracting important information from facial images. Motivated by the above mentioned and the high amount of applications in facial analysis, security systems and Biometry, in this thesis as a first time, we propose to use an unique image representation, the Gaussian Scale Space computed with a half octave pyramid. We show in this thesis that this image representation could be used to perform different tasks in facial analysis without lost of performance compared with other approaches in the state-of-the-art that uses more complicated image representations. it is also well know that using an unique image represenation could be convenient in real world applications where the amount of memory capacity is limitated by hardware constraints. To demostrate our assumptations we solve three different tasks in facial analysis: Face detection, Face recognition and Age estimation. In face detection we propose to use a cascade of classifiers using Gaussian derivatives. Specifically we propose to use Gaussian derivatives up to the fourth order, in effect experiemnts using different derivatives orders have shown that fourth order Gaussian derivatives provide important information in face detection and recognition. In adition, to improve the speed of detection using Gaussian derivatives, we develope a new cascade architecture which considerates the computational cost of each Gaussian derivative order to chose its best position in the cascade. Finally, to solve the face recognition and age estimation problems, we propose a tensorial model based in Gaussian derivatives. This tensorial model preserves the 3-D structure of feature space and it does not break the natural structure of data when a vectorization process is applied. Each one of the methods proposed in the thesis are discused and validated with a set of well defined experiments. All our results are compared with the last state-of-the-art results in face detection, recognition and age estimation, giving comparable or superior results

L'objectif de cette thèse est l'étude d'un descripteur d'images adapté à une grande variété d'applications. Nous cherchons à obtenir un descripteur robuste et discriminant, facile à adapter et peu coûteux en calcul et en mémoire.Nous définissons un nouveau descripteur, composé de valeurs du Laplacien à différentes échelles et de valeurs d'une transformée de Fourier radiale, calculées à partir d'une pyramide Gaussienne. Ce descripteur capture une information de forme multi-échelle autour d'un point de l'image. L'expérimentation a montré que malgré une taille mémoire réduite les performances en robustesse et en pouvoir discriminant de ce descripteur sont à la heuteur de l'état de l'art.Nous avons expérimenté ce descripteur avec trois types de tâches différentes.Le premier type de tâche est la mise en correspondance de points-clés avec des images transformées par rotation, changement d'échelle, floutage, codage JPEG, changement de point de vue, ou changement d'éclairage. Nous montrons que la performance de notre descripteur est au niveau des meilleurs descripteurs connus dans l'état de l'art. Le deuxième type de tâche est la détection de formes. Nous avons utilisé le descripteur pour la création de deux détecteurs de personnes, construits avec Adaboost. Comparé à un détecteur semblable construit avec des histogrammes de gradients (HOG) nos détecteurs sont très compétitifs tout en utilisant des descripteurs sensiblement plus compacts. Le dernier type de tâche est la détection de symétries de réflexion dans des images "du monde réel". Nous proposons une technique de détection d'axes potentiels de symétries en miroir. Avec cette tâche nous montrons que notre descripteur peut être genéralisé à des situations complexes. L'expérimentation montre que cette méthode est robuste et discriminante, tout en conservant un faible coût en calcul et en mémoire. / In this thesis we explore a new image description method composed of a multi-scale vector of Laplacians of Gaussians, the Laplacian Profile, and a Radial Fourier Transform. This method captures shape information with different proportions around a point in the image. A Gaussian pyramid of scaled images is used for the extraction of the descriptor vectors. The aim of this new method is to provide image description that can be suitable for diverse applications. Adjustability as well as low computational and memory needs are as important as robustness and discrimination power. We created a method with the ability to capture the image signal efficiently with descriptor vectors of particularly small length compared to the state of the art. Experiments show that despite its small vector length, the new descriptor shows reasonable robustness and discrimination power that are competitive to the state of the art performance.We test our proposed image description method on three different visual tasks. The first task is keypoint matching for images that have undergone image transformations like rotation, scaling, blurring, JPEG compression, changes in viewpoint and changes in light. We show that against other methods from the state of the art, the proposed descriptor performs equivalently with a very small vector length. The second task is on pattern detection. We use the proposed descriptor to create two different Adaboost based detectors for people detection in images. Compared to a similar detector using Histograms of Oriented Gradients (HOG), the detectors with the proposed method show competitive performance using significantly smaller descriptor vectors. The last task is on reflection symmetry detection in real world images. We introduce a technique that exploits the proposed descriptor for detecting possible symmetry axes for the two reflecting parts of a mirror symmetric pattern. This technique introduces constraints and ideas of how to collect more efficiently the information that is important to identify reflection symmetry in images. With this task we show that the proposed descriptor can be generalized for rather complicated applications. The set of the experiments confirms the qualities of the proposed method of being easily adjustable and requires relatively low computational and storage requirements while remaining robust and discriminative.

One of the methods for collecting data in psychology is a method of semantic differential. The using of semantic differential is very large, this method is widely used in personality research, clinical psychology, market psychology and marketing. In recent years, this method has begun to apply to the area of educational research, above all educational psychology. A basic problem with wide using is the huge volume of data obtained by this method. Some of the options of setting up of a questionnaire with light to the selection of bipolar adjectives are listed in the thesis. The options represent the evaluation dimension, the dimension of activity and potency in terms of both representativeness and relevance. A set of tools for automatized generation of various combinations of questionnaire groups was created. A technical support of data collection, their evaluation and visualization using semantic differential method was also created. These methods will be used in realization of the project of introducing teaching of mathematic in English language at primary schools. The primary goal of this level of analysis is to judge to what extent can two terms (or more terms), generally regarded as semantically similar or different.

Every environment is susceptible to risks and Wireless Local Area Networks (WLANs) based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard are no exception. The most apparent risk of WLANs is the ease with which itinerant intruders obtain illicit entry into these networks. These intrusion security risks must therefore be addressed which means that information security risk analysis and risk management need to be considered as integral elements of the organisation’s business plan. A well-established qualitative risk analysis and risk management methodology, the Operationally Critical Threat Asset and Vulnerability Evaluation (OCTAVE) is selected for conducting the WLAN intrusion security risk analysis and risk management process. However, the OCTAVE risk analysis methodology is beset with a number of problems that could hamper a successful WLAN intrusion security risk analysis. The ultimate deliverable of this qualitative risk analysis methodology is the creation of an organisation-wide protection strategy and risk mitigation plan. Achieving this end using the OCTAVE risk analysis methodology requires an inordinate amount of time, ranging from months to years. Since WLANs are persistently under attack, there is a dire need for an expeditious risk analysis methodology. Furthermore, the OCTAVE risk analysis methodology stipulates the identification of assets and corresponding threat scenarios via a brainstorming session, which may be beyond the scope of a person who is not proficient in information security issues. This research was therefore inspired by the pivotal need for a risk analysis and risk management methodology to address WLAN intrusion attacks and the resulting risks they pose to the confidentiality, integrity and availability of information processed by these networks. Copyright / Dissertation (MSc (Computer Science))--University of Pretoria, 2006. / Computer Science / unrestricted

Background: For the past 50+ years, audiologists have been taught to measure the pure-tone thresholds at the interoctave frequencies when the thresholds at adjacent octave frequencies differ by 20 dB or more. Although this so-called 20 dB rule is logical when enhanced audiometric resolution is required, the origin of the rule is elusive, and a thorough literature search failed to find supporting scientific data. Purpose: This study purposed to examine whether a 20 dB difference between thresholds at adjacent octave frequencies is the critical value for whether the threshold of the interoctave frequency should be measured. Along this same line of questioning is whether interoctave thresholds can be predicted from the thresholds of the adjacent or bounding octave frequencies instead of measured, thereby saving valuable time. Research Design: Retrospective, descriptive, correlational, and cross-sectional. Study Sample: Audiograms from over a million veterans provided the data, which were archived at the Department of Veterans Affairs, Denver Acquisition and Logistics Center. Data Collection and Analysis: Data from the left and right ears were independently evaluated. For each ear three interoctave frequencies (1500, 3000, and 6000 Hz) were studied. For inclusion, thresholds at the interoctave frequency and the two bounding octave frequencies had to be measurable, which produced unequal numbers of participants in each of the six conditions (2 ears by 3 interoctave frequencies). Age tags were maintained with each of the six conditions. Results: Three areas of analyses were considered. First, relations among the octave-frequency thresholds were examined. About 62% of the 1000-2000 Hz threshold differences were ≥20 dB, whereas about 74% of the 4000-8000 Hz threshold differences were <20 dB. About half of the threshold differences between 2000 and 4000 Hz were <20 dB and half were >20 dB. There was an inverse relation between frequency and the percent of negative slopes between octave-frequency thresholds, ranging from 89% at 1500 Hz to 54% at 6000 Hz. The majority of octave-frequency pairs demonstrated poorer thresholds for the higher frequency of the pair. Second, interoctave frequency thresholds were evaluated using the median metric. As the interoctave frequency increased from 1500 to 6000 Hz, the percent of thresholds at the interoctave frequencies that were not equal to the median threshold increased from ∼9.5% (1500 Hz) to 15.6% (3000 Hz) to 28.2% (6000 Hz). Bivariate plots of the interoctave thresholds and the mean octave-frequency thresholds produced 0.85-0.91 R2 values and 0.79-0.92 dB/dB slopes. Third, the predictability of the interoctave thresholds from the mean thresholds of the bounding octave frequencies was evaluated. As expected, as the disparity between octave-frequency thresholds increased, the predictability of the interoctave threshold decreased; for example, using a ±5 dB criterion at 1500 Hz, 53% of the thresholds were ±5 dB when the octave thresholds differed by ≥20 dB, whereas 77% were ±5 dB when the octave thresholds differed by <20 dB. Conclusions: The current findings support the 20 dB rule for testing interoctave frequency thresholds and suggest the rule could be increased to 25 dB or more with little adverse effect.

No description available.

Elements of continuous variation such as tremolo, vibrato and portamento enable dimensions of their own in expressive melodic music in styles such as in Indian Classical Music. There is published work on parametrically modeling some of these elements individually, and to apply the modeled parameters to automatically generated musical notes in the context of machine musicianship, using simple rule-based mappings. There have also been many systems developed for generative musical accompaniment using probabilistic models of discrete musical elements such as MIDI notes and durations, many of them inspired by computational research in linguistics. There however doesn't seem to have been a combined approach of parametrically modeling expressive elements in a probabilistic framework. This documents presents a real-time computational framework that uses a multi-attribute trie / n-gram structure to model parameters like frequency, depth and/or lag of the expressive variations such as vibrato and portamento, along with conventionally modeled elements such as musical notes, their durations and metric positions in melodic audio input. This work proposes storing the parameters of expressive elements as metadata in the individual nodes of the traditional trie structure, along with the distribution of their probabilities of occurrence. During automatic generation of music, the expressive parameters as learned in the above training phase are applied to the associated re-synthesized musical notes. The model is aimed at being used to provide automatic melodic accompaniment in a performance scenario. The parametric modeling of the continuous expressive elements in this form is hypothesized to be able to capture deeper temporal relationships among musical elements and thereby is expected to bring about a more expressive and more musical outcome in such a performance than what has been possible using other works of machine musicianship using only static mappings or randomized choice. A system was developed on Max/MSP software platform with this framework, which takes in a pitched audio input such as human singing voice, and produces a pitch track which may be applied to synthesized sound of a continuous timbre. The system was trained and tested with several vocal recordings of North Indian Classical Music, and a subjective evaluation of the resulting audio was made using an anonymous online survey. The results of the survey show the output tracks generated from the system to be as musical and expressive, if not more, than the case where the pitch track generated from the original audio was directly rendered as output, and also show the output with expressive elements to be perceivably more expressive than the version of the output without expressive parameters. The results further suggest that more experimentation may be required to conclude the efficacy of the framework employed in relation to using randomly selected parameter values for the expressive elements. This thesis presents the scope, context, implementation details and results of the work, suggesting future improvements.

Thesis (PhD (Electrical and Electronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Passive millimetre-wave (PMMW) imaging is a technique that uses radiometers to detect thermal radiation emitted and reflected by metallic and non-metallic objects. While visual and infra-red emissions are attenuated by atmospheric constituents, PMMW emissions are transmitted, resulting in consistent contrast between different objects from day to night in clear weather and in low-visibility conditions to form images for a range of security and inclement weather applications. The use of a PMMW imaging system on a small unmanned aerial vehicle (UAV) offers extremely attractive possibilities for applications such as airborne surveillance for search and rescue operations, which are often hindered by inclement weather making visibility poor and endangering the rescuers as the search vehicle flies through the bad weather zone. The UAV would fly above the bad weather zone, with the PMMW imaging system detecting the thermal radiation emitted and reflected by objects in the MMW spectrum through the inclement weather. The 35GHz propagation window is chosen for the greater transmission through atmospheric constituents. The design of the PMMW imaging system is severely limited by the size of the UAV, particularly in the inability to incorporate any form of optical or mechanical scanning antenna. A possible solution is a long, thin antenna array fitted under the wings of the UAV. Such an antenna has a narrow, high gain, frequency-scanned beam along the plane perpendicular to the flight path, but a very broad beam along the plane of the flight path blurs the image, making it difficult to accurately determine the position of an object or to differentiate between objects situated along the plane of the flight path. This dissertation proposes a technique of image reconstruction based on the Kalman filter, a recursive filter that uses feedback control to estimate the state of a partially observed non-stationary stochastic process, to reconstruct an accurate image of the target area from such a detected signal. It is shown that given a simulated target area, populated with an arbitrary number of objects, the Kalman filter is able to successfully reconstruct the image using the measured antenna pattern to model the scanning process and reverse the blurring effect / AFRIKAANSE OPSOMMING: Passiewe millimetergolf (PMMG) beeldvorming is ’n tegniek wat van radiometers gebruik maak om termiese straling waar te neem vanaf beide metaal en nie-metaal voorwerpe. Waar optiese en infra-rooi straling attenueer word deur atmosferiese bestanddele, plant PMMG strale ongehinderd voort. Dit lei tot konstante kontras tussen verskillende voorwerpe in daglig of snags, mooi of bewolkte weer, en in ander lae-sigbaarheid toestande om beelde te vorm vir ’n wye reeks sekuriteits- of weertoepassings. Die gebruik van PMMG beeldvorming op ’n klein onbemande lugtuig (OLT) bied aantreklike moontlikhede vir toepassings in observasie en reddingsoperasies, wat dikwels verhinder word deur bewolke weer wat reddingswerkers in gevaar stel as hul moet vlieg in toestande van lae sigbaarheid. Die OLT kan bokant die onweer vlieg, met die PMMG beeldvormer wat termiese straling in die millimetergolf spektrum vanaf voorwerpe kan waarneem in swaks weerstoestande. Vir verbeterde golfvoortplanting deur atmosferiese bestanddele, word die 35GHz band gekies. Die ontwerp van die PMMG stelsel word geweldig beperk deur die grootte van die OLT, spesifiek deur die tuig se onvermoë om ’n antenne te huisves wat opties of meganies kan skandeer. ’n Moontlike oplossing is om gebruik te maak van ’n lang, dun antenne samestelling wat onder die OLT se vlerke geplaas word. So ’n antenne het ’n nou, hoë-aanwins bundel wat met frekwensie skandeer langs ’n vlak loodreg tot die vlugtrajek. So ’n antenne het egter ’n baie wye bundel langs die vlugtrajek, wat beeldkwaliteit verlaag en dit moeilik maak om die posisie van ’n voorwerp langs die vlugtrajek te bepaal, of om tussen veelvuldige voorwerpe te onderskei. Hierdie proefskrif bied ’n tegniek van beeldherwinning gebaseer op die Kalman filter, ’n rekursiewe filter wat terugvoerbeheer gebruik om die toestand van ’n nie-stasionêre stochastiese proses af te skat wat slegs gedeeltelik waargeneem is, om soedoende ’n akkurate beeld van die teikenarea te herkonstrueer vanuit ’n verwronge beeld. Dit word getoon dat, gegewe ’n gesimuleerde teikenomgewing met ’n arbitrêre hoeveelheid voorwerpe, die Kalman filter suksesvol ’n beeld kan herkonstrueer deur gebruik te maak van die antenne se gemete stralingspatroon om die skanderingsproses na te boots, om sodoende die beeldkwaliteit te verhoog

De légendaires, les grandes figures féminines des mythes anciens sont devenues, au fil du XIXe siècle, emblématiques. Le mouvement s’amplifie vers la fin du siècle et l’imaginaire « féminin » se nourrit alors d’un discours social qui contribue à construire la féminité en termes de menace et de dépravation. Les figures mythiques prêteront leurs traits à celle de la femme fatale, devenue le symbole de la dégénérescence de la société française. Engrangeant dans son corps représenté tous les vices du siècle, la figure féminine nous est apparue éminemment révélatrice quant à la compréhension d’une époque. Or, la figure de la femme fatale s’avère fondamentalement ambivalente et Lilith, pouvant à la fois incarner l’amour et la destruction, affiche ce double visage de la féminité. Nous démontrons qu’il existe une relation étroite entre la profonde ambivalence du mythe de Lilith et les représentations de la femme fatale et pour ce faire, procédons à une analyse comparative de l’œuvre de Rachilde et Octave Mirbeau qui, dans La Jongleuse et Le Jardin des supplices, réécrivent le mythe de Lilith. De la comparaison des deux Lilith, ressortent deux représentations extrêmement contrastées de la femme fatale : alors que Rachilde dresse toute droite son héroïne dans son désir ascensionnel, Mirbeau construit une Clara toute en mollesse et assoiffée de chair. Par l’analyse des rapports qui s’articulent entre deux écritures, nous démontrons que la dualité inhérente au mythe de Lilith répond à l’instabilité d’une société aux prises avec de multiples angoisses en matière d’identité sexuelle. Cette comparaison nous amène aussi à nous interroger quant aux traces d’une certaine sexuation dans la voix littéraire. / Over the course of the nineteenth century the legendary female figures of ancient myth had become emblematic of the female sex. This association grew stronger toward the end of the century and the “feminine imaginary” fed itself on a social discourse that contributed to the construction of femininity in terms of menace and depravity. The mythical figures that lent their faces to representations of the femme fatale became symbols of the degeneration of French society. With all of the vices of the century gathered into her body, this female figure appears to us as eminently revealing as to the understanding of an era. However, the figure of the femme fatale is fundamentally ambivalent, and the mythical figure of Lilith, which can embody love as well as destruction, represents the two opposing aspects of nineteenth century representations of femininity. This study shows that there is a direct relationship between the profound ambivalence that characterizes the myth of Lilith and representations of the femme fatale. To this end, we undertake a comparative analysis of the works of Rachilde and Octave Mirbeau, who rewrite the myth of Lilith in The Juggler and The Torture Garden. Two extremely contrasting representations emerge from the comparison between the two “Liliths”: as Rachilde portrays her upstanding heroine’s desire to transcend her body, Mirbeau constructs his Clara as soft and mired in the body, thirsty for carnal pleasure. By examining the relationships that become apparent between these works, we demonstrate that the duality inherent in the myth of Lilith responds to the instability of a society grappling with multiple anxieties regarding sexual identity. This comparison, therefore, allows us to interrogate the traces of a specific mode of sexuation in the literary voice.