Title: Colour reproduction accuracy of stochastic spectral sampling: an experi- mental evaluation Author: Bc. Attila Hencz �attila.hencz@matfyz.cz� Department: Department of Software and Computer Science Education Supervisor: doc. Alexander Wilkie, Dr. �wilkie@cgg.mff.cuni.cz�, Department of Software and Computer Science Education Abstract: We investigate the colorimetric accuracy of stochastic sampling in the wavelength domain for realistic rendering purposes. In particular, we consider the impact of three specific design choices in a rendering system on the accuracy of the overall result: how exactly spectral samples are splatted into the final result spectrum, how many spectral channels one uses in the result images, and the impact of Hero Wavelength Spectral Sampling (HWSS) compared to the stand- ard monochrome technique. We provide experimental results, comparisons and evaluation of sampling high-resolution spectra that originate from measurements of real paint samples found in colour atlases, and normed light sources defined by the CIE. The latter include both smooth and spiky spectra, so the used com- bination of reflectances and light spectra provides a representative body of input values that allows to draw conclusions that are relevant for practical rendering work. Keywords: physically based image...

The aim of the study was to explore and describe the feelings of people with physical disabilities regarding discrimination in the community of Tembisa. Discrimination against people with physical disabilities is one of the major problems affecting the larger society, impacting on their lives. The exploratory and descriptive designs were used because of insufficient information available on this topic particularly in Tembisa and to describe the feelings of people with disabilities regarding discrimination. A semi-structured interview schedule was used as a data-gathering instrument. The study was conducted among people with physical disabilities who are clients of the organisation Association for Physically Disabled (APD). Ten respondents were then selected following a purposive non-probability sampling method. The study revealed that most people with physical disabilities experience difficulty in accessing some of the public buildings in Tembisa as they are not wheelchair friendly. Housing for people with disabilities was also raised as another problem experienced by people with disabilities in general. The findings further proved that not much has been done regarding inclusion of people with disabilities by employing them in the open labour market. In conclusion, it has been proved that people with disabilities feel isolated, rejected, marginalised and stigmatised in the community of Tembisa by their able-bodied counterparts. Recommendations are provided regarding how people with disabilities can be included in Tembisa and mainstream society. / Dissertation (MA(Social Work)(Health Care))--University of Pretoria, 2005. / Social Work / unrestricted

Les fonctions non clonables physiquement, appelées PUF (Physically Unclonable Functions), représentent une technologie innovante qui permet de résoudre certains problèmes de sécurité et d’identification. Comme pour les empreintes humaines, les PUF permettent de différencier des circuits électroniques car chaque exemplaire produit une signature unique. Ces fonctions peuvent être utilisées pour des applications telles que l’authentification et la génération de clés cryptographiques. La propriété principale que l’on cherche à obtenir avec les PUF est la génération d’une réponse unique qui varie de façon aléatoire d’un circuit à un autre, sans la possibilité de la prédire. Une autre propriété de ces PUF est de toujours reproduire, quel que soit la variation de l’environnement de test, la même réponse à un même défi d’entrée. En plus, une fonction PUF doit être sécurisée contre les attaques qui permettraient de révéler sa réponse. Dans cette thèse, nous nous intéressons aux PUF en silicium profitant des variations inhérentes aux technologies de fabrication des circuits intégrés CMOS. Nous présentons les principales architectures de PUF, leurs propriétés, et les techniques mises en œuvre pour les utiliser dans des applications de sécurité. Nous présentons d’abord deux nouvelles structures de PUF. La première structure appelée “Loop PUF” est basée sur des chaînes d’éléments à retard contrôlés. Elle consiste à comparer les délais de chaînes à retard identiques qui sont mises en série. Les points forts de cette structure sont la facilité de sa mise en œuvre sur les deux plates-formes ASIC et FPGA, la grande flexibilité pour l’authentification des circuits intégrés ainsi que la génération de clés de chiffrement. La deuxième structure proposée “TERO PUF” est basée sur le principe de cellules temporairement oscillantes. Elle exploite la métastabilité oscillatoire d’éléments couplés en croix, et peut aussi être utilisée pour un générateur vrai d’aléas (TRNG). Plus précisément, la réponse du PUF profite de la métastabilité oscillatoire introduite par une bascule SR lorsque les deux entrées S et R sont connectées au même signal d’entrée. Les résultats expérimentaux montrent le niveau de performances élevé des deux structures de PUF proposées. Ensuite, afin de comparer équitablement la qualité des différentes PUF à retard, nous proposons une méthode de caractérisation spécifique. Elle est basée sur des mesures statistiques des éléments à retard. Le principal avantage de cette méthode vient de sa capacité à permettre au concepteur d’être sûr que la fonction PUF aura les performances attendues avant sa mise en œuvre et sa fabrication. Enfin, en se basant sur les propriétés de non clonabilité et de l’imprévisibilité des PUF, nous présentons de nouvelles techniques d’authentification et de génération de clés de chiffrement en utilisant la “loop PUF” proposée. Les résultats théoriques et expérimentaux montrent l’efficacité des techniques introduites en termes de complexité et de fiabilité / Physically Unclonable Functions, or PUFs, are innovative technologies devoted to solve some security and identification issues. Similarly to a human fingerprint, PUFs allows to identify uniquely electronic devices as they produce an instance-specific signature. Applications as authentication or key generation can take advantage of this embedded function. The main property that we try to obtain from a PUF is the generation of a unique response that varies randomly from one physical device to another without allowing its prediction. Another important property of these PUF is to always reproduce the same response for the same input challenge even in a changing environment. Moreover, the PUF system should be secure against attacks that could reveal its response. In this thesis, we are interested in silicon PUF which take advantage of inherent process variations during the manufacturing of CMOS integrated circuits. We present several PUF constructions, discuss their properties and the implementation techniques to use them in security applications. We first present two novel PUF structures. The first one, called “Loop PUF” is a delay based PUF which relies on the comparison of delay measurements of identical serial delay chains. The major contribution brought by the use of this structure is its implementation simplicity on both ASIC and FPGA platforms, and its flexibility as it can be used for reliable authentication or key generation. The second proposed structure is a ring-oscillator based PUF cells “TERO PUF”. It exploits the oscillatory metastability of cross-coupled elements, and can also be used as True Random Number Generator (TRNG). More precisely, the PUF response takes advantage from the introduced oscillatory metastability of an SR flip-flop when the S and R inputs are connected to the same input signal. Experimental results show the high performance of these two proposed PUF structures. Second, in order to fairly compare the quality of different delay based PUFs, we propose a specific characterization method. It is based on statistical measurements on basic delay elements. The main benefit of this method is that it allows the designer to be sure that the PUF will meet the expected performances before its implementation and fabrication. Finally, Based on the unclonability and unpredictability properties of the PUFs, we present new techniques to perform “loop PUF” authentication and cryptographic key generation. Theoretical and experimental results show the efficiency of the introduced techniques in terms of complexity and reliability

Tensors are of great interest to many applications in engineering and in medical imaging, but a proper analysis and visualization remains challenging. Physics-based visualization of tensor fields has proven to show the main features of symmetric second-order tensor fields, while still displaying the most important information of the data, namely the main directions in medical diffusion tensor data using texture and additional attributes using color-coding, in a continuous representation. Nevertheless, its application and usability remains limited due to its computational expensive and sensitive nature. We introduce a novel approach to compute a fabric-like texture pattern from tensor fields on arbitrary non-selfintersecting surfaces that is motivated by image space line integral convolution (LIC). Our main focus lies on regaining three-dimensionality of the data under user interaction, such as rotation and scaling. We employ a multi-pass rendering approach to estimate proper modification of the LIC noise input texture to support the three-dimensional perception during user interactions.

Title: The effects of extreme physical and mental stress on the human body Goals: The main goal of this work was to evaluate the effect of physical stress load in a five-kilometer-long race in cross-country skiing on physical and mental functions of high school students. Methods: The investigated group consisted of 10 boys of the average age of 16 years. To evaluate their level of physical fitness and circulatory responses during cross-country stress, the maximal treadmill stress test was used. Circulatory response before, during, and after the race was monitored by a Sport-tester. To evaluate the mental background and the actual condition under the stress load, standardized questionnaires on ability to cross-country skiing, stress management strategy, degree of physical discomfort and current mental state were used. Results: The reference file tested by a stress test up to the maximum proved an above-average aerobic fitness. The extreme stress situation was a five-kilometer-long race in cross-country skiing. The results were processed and evaluated with a statistical and factual relevance. A number of correlations were made. The average SF values, which were achieved during the race, were getting near the maximum values (96% of SF max.). Even the evaluation by a Borg RPE scale attested to the...

In the recent decades, therehave been frequent conflicts between groundwater waterresources and environmentally hazardous activities. Newmethodologies for aiding decision-making in groundwater impactassessment and protection areneeded and in which issues ofincreased awareness, better understanding of the groundwaterresources processes, and validation of predictive mathematicalmodels are addressed. A framework fordecision–aid, based on predictive simulations that a)predicts the environmental impacts b) provides the totaleconomical value c) visualises the impacts and the groundwaterproperties and d) describes the uncertainties in the results isproposed herein. The framework can be applied in environmentalimpact assessments, strategic environmental assessments andprotection and management of water resources. The results ofthe model are used as feedback for determining new scenarios,depending on the required uncertainties, and if the plannedactivity is sustainable, and/or fulfils the legislative andpolicy measures. This framework is applied to a particular casestudy, Nybroåsen, in the south-eastern part of Sweden,where the highway E22 is constructed through the importantglaciofluvial esker aquifer, passing the protection zone of thewater supply for the Kalmar municipality. The impacts from the new highwayand the existing road have been predicted by two-dimensionalphysically based time-variant flow and solute groundwatermodelling. The results, breakthrough curves of contaminantconcentration in wells and maps of concentration distributions,as well as travel times, flow paths, and capture zones forwells determined by particle tracking have been presented. The constructed model of theNybroåsen study area was calibrated by comparing observedand simulated groundwater levels for 15 observation wells forten years of measurements. The model has been evaluated bothgraphically and numerically and the calibration target wasfulfilled for 13 of the 15 observation wells. The model workincludes investigations of the catchment information, a waterbalance study, simulation of the groundwater recharge,consideration of the unsaturated zone by a numerical columnsimulation, and sensitivity analysis. From the sensitivity analysis ofthe flow and transport parameters, it has been shown that theuncertainties are mainly due to the hydraulic conductivity.Comparison of the derived conductivity from the steady-stateautomatic calibration and the time-variant calibration showedthat there are major differences in the derived parameters,which illustrates the importance of a time dependentcalibration over both wet and dry periods and in more than onepoint in the area of interest of the model predictions. In addition, a multi-criteriadecision analysis has been carried out for four roadalternatives (including the new highway E22) and the existingroad in the case study concerned. The multi-criteria decisionaid is applied as an illustration of how it can be used in thestudy area to identify a) interest groups of actors and theirconcerns b) ranking of alternative road scenarios according toactors’preferences and c) coalition groups of actorsi.e.groups that have similar views with regard to theroad alternatives. <b>Keywords:</b>Physically-based groundwater modelling,contamination, flow and solute transport, glaciofluvialdeposits, Nybroåsen, Sweden, and multi-criteriadecision-aid. / NR 20140805

Groundwater is a sensitive component affected by climate change. Modelling the dynamics of groundwater levels is inherently difficult particularly as the response to climate change. Given this complexity, most of the current studies using long term groundwater time series were conducted by statistical analysis or using over simplified assumptions to represent the physical processes in hydrological system. With the objective of providing an improved physically based groundwater modelling approach to support climate change impact assessment, a dataset of long term time series of groundwater levels from two different soil types (sand and till) were selected from the Tärnsjö area located in southeast of Sweden. The CoupModel was chosen to perform the simulation since it offers a physically based representation on groundwater recharge processes. A two-step strategy for calibration with first short-term calibration followed by long-term testing was adopted. Simulated groundwater levels followed the general patterns of measured groundwater level dynamics; however, auto-correlations and periodicities were observed in residuals for all sites of which two sandy soil sites with deeper groundwater tables maintained strong auto-correlations in long time lags and an extra 15.4-year periodicity. The long memory of the system rendered it more susceptible to climate change. Uncertainty arises if different initial condition had been applied in short term period calibration.

This thesis deals with design, implementation and analysis of the model for dynamic changes in the terrain. Present state of terrain deformation in OpenSceneGraph environment is described and available relevant software called TDS, which allows terrain adaptation to new inserted objects is presented. Special emphasis is placed on design of model for physically based terrain deformations that are caused by moving object or by bomb explosion. The results of simulation tests are presented and on the base of model analysis, the optimizations, which significantly improve final algorithm, are designed and realized.

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