京都大学 / 新制・課程博士 / 博士(人間・環境学) / 甲第25367号 / 人博第1109号 / 新制||人||259(附属図書館) / 京都大学大学院人間・環境学研究科共生人間学専攻 / (主査)教授 日置 尋久, 教授 立木 秀樹, 准教授 DE BRECHTMatthew, 教授 下田 宏, 教授 小山田 耕二 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DGAM

No / A comparison is presented between two indoor localization algorithms using received signal strength, namely the vector algorithm and the Comparative Received Signal Strength (CRSS) algorithm. Signal values were obtained using ray tracing software and processed with MATLAB to ascertain the effects on localization accuracy of radio map resolution, number of access points and operating frequency. The vector algorithm outperforms the CRSS algorithm, which suffers from ambiguity, although that can be reduced by using more access points and a higher operating frequency. Ambiguity is worsened by the addition of more reference points. The vector algorithm performance is enhanced by adding more access points and reference points while it degrades with increasing frequency provided that the statistical mean of error increased to about 60 cm for most studied cases. / No full text available. Unable to contact the publisher.

The proposed dissertation thesis contains an analysis of conditions on the boundary between layers having varied electromagnetic properties. The research is performed using consistent theoretical derivation of analytical formulas, and the underlying problem is considered also in view of multiple boundaries including the effect of the propagation of electromagnetic waves having different instantaneous speed. The author presents a survey and formulation of the basic characteristics of methods used for electromagnetic wave propagation analysis; in this respect, special emphasis is placed on radial models. The processing of the topic involved the designing and verification (using a set of different, layered planar materials) of algorithms to analyze the electromagnetic field components. The algorithm was assembled to enable simple evaluation of all components of the electromagnetic field in relation to the speed of the wave propagation in a heterogeneous environment. The proposed algorithms are compared by means of different numerical methods for the modelling of electromagnetic waves on the boundary between materials; moreover, electromagnetic field components in common points of the model were also subject to comparison. When in conjunction with tools facilitating the analysis of material response to the source of a continuous signal, the algorithms constitute a supplementary instrument for the design of a layered material. Such design enables the realization of, for example, recoilless plane, recoilless transition between different types of environment, and filters for both optical and radio frequencies.

This research delves into wireless communication systems, with a particular focus on initial access processes, channel modeling, and beamforming strategies. The study involves meticulous channel data collection across diverse urban, suburban, and rural terrains, each presenting unique propagation challenges. The research also simulates a typical communication network with four base stations, adjusting their configurations to suit the varied terrains. A central focus is the implementation of the cell search methodology, including the exploration of random beamforming at both system and cell levels. The findings indicate that the cell-level system configurations do not yield significant performance improvements over the baseline configuration. Furthermore, potential increased costs associated with this strategy are noted. However, it is essential to highlight that this project serves as a critical exploration of the potential benefits of random beamforming at the cell level within non-public network scenarios. While the improvements observed are minimal, the insights gained from this research are poised to guide future research endeavors and contribute to the elimination of uncertainties in the field of wireless communication. / Denna forskning fördjupar sig i trådlösa kommunikationssystem, med särskilt fokus på initiala åtkomstprocesser, kanalmodellering och strålformningsstrategier. Studien involverade noggrann kanaldatainsamling över olika urbana, förorts- och landsbygdsterränger, var och en med unika spridningsutmaningar. Forskningen simulerade också ett typiskt kommunikationsnätverk med fyra basstationer som justerade deras konfigurationer för att passa de varierande terrängerna. Ett centralt fokus var implementeringen av cellsökningsmetoden, inklusive utforskning av slumpmässig strålformning på både system- och cellnivå. Resultaten indikerade att systemkonfigurationerna på cellnivå inte gav signifikanta prestandaförbättringar jämfört med baslinjekonfigurationen. Dessutom noterades potentiella ökade kostnader förknippade med denna strategi. Det är dock viktigt att betona att detta projekt fungerade som en kritisk utforskning av de potentiella fördelarna med slumpmässig strålformning på cellnivå inom icke-offentliga nätverksscenarier. Även om de observerade förbättringarna var minimala, är insikterna från denna forskning redo att vägleda framtida forskningsinsatser och bidra till att eliminera osäkerheter inom området trådlös kommunikation.

Ziel dieser Arbeit ist es einerseits, allgemeine Erwartungen an die Bedienabläufe eines Fahrerinformationssystems zu ermitteln, welche Benutzer aus ihren Vorerfahrungen mit anderen technischen Geräten mitbringen, und andererseits zu zeigen, dass sich die Anpassung der Bedienabläufe eines Fahrerinformationssystems an diese allgemeinen Benutzererwartungen vorteilhaft auf die Gebrauchstauglichkeit des Gerätes auswirkt. Dabei wird eine Erwartung, welche in einer bestimmten Bediensituation an das Gerät besteht, verstanden als das mentale Modell von der Funktionsweise des Systems, welches der Benutzer in genau dieser Situation aus seinem schematischen Vorwissen und Merkmalen der Bedienoberfläche des zu bedienenden Gerätes bildet. In einer ersten Studie werden zunächst durch einen Vergleich mit dem konzeptuellen Modell eines bestehenden Fahrerinformationssystems diejenigen mentalen Modelle der Benutzer von Bedienabläufen identifiziert, welche interindividuell übereinstimmen. Dazu wird eine auf process tracing aufbauende, eigens entwickelte Methodik eingesetzt, welche es ebenfalls erlaubt, für diese Erwartungen diejenigen Aspekte zu ermitteln, welche unabhängig von speziellen Merkmalen des untersuchten Systems auch für Bedienabläufe eines Fahrerinformationssystems generell zutreffen. In einer nächsten Studie werden die ermittelten systemunabhängigen Benutzererwartungen verifiziert, indem aus ihnen das Bedienverhalten für ein zweites FIS mit anderem Bedienkonzept vorhergesagt wird. Dank der Verwendung des gleichen, handlungspsychologisch definierten Analyseniveaus für mentale und konzeptuelle Modelle können die verifizierten systemunabhängigen, interindividuell übereinstimmenden Benutzererwartungen als konzeptuelle Modelle in Form von Status-Übergangs-Diagrammen dargestellt und so als allgemeine Gestaltungsempfehlungen für Bedienabläufe in Fahrerinformationssystemen festgehalten werden. In einer dritten Studie werden die Bedienabläufe eines Prototypen entsprechend den allgemeinen Benutzererwartungen gestaltet und gegenüber Bedienabläufen evaluiert, welche von den Benutzererwartungen abweichen. Dabei zeigt sich, dass Bedienabläufe, welche mit den allgemeinen mentalen Modellen der Benutzer übereinstimmen, zu besseren Bedienleistungen und Systembewertung auf Seiten der Benutzer führen. Die formulierten allgemeinen Gestaltungsempfehlungen sind meist generalisierbar auf andere Domänen und die Ergebnisse dieser Arbeit bieten Ansatzpunkte für zukünftige Forschungsarbeiten. / The presented research project has two main goals: To learn about the nature of users’ general expectancies towards the operation of infotainment systems in passenger cars and to show that designing the paths of operation according to the users’ expectancies has positive effects on the usability of such systems. An expectancy at a certain point in the course of operation is understood as the mental model which the user forms of the system’s functionality in this situation on the basis of the system’s interface’s properties and his or her past experiences with other technical devices. A first study compares the conceptional model of an existing in-car infotainment system with the mental models of people using this system and thus identifies which mental models are shared interindividually by a majority of the users. The methodology used in this study was developed based on process tracing and permitted to equally identify those aspects of the mental models which are independent of the specific interaction concept of the examined system and therefore apply to the paths of operation of any in-car infotainment system in general. A next study verifies the users’ system-independent expectancies found in the first study by predicting users’ behavior during the operation of a second system with a different user interface. Both the users’ mental models and the systems’ conceptional models are analyzed and described using the same level of abstraction which is defined on the basis of action regulation theory. Thus directly comparable to the conceptional models, the users’ expectancies are described as state-transition diagrams which in turn as conceptional models represent the derived recommendations for the design of operational paths in infotainment systems. A third study uses a prototype system to evaluate paths of operation which have been designed according to the general recommendations versus paths of operation which deviate from the users’ expectancies. The results of this third study show that a system with paths of operation matching the users’ general mental models permits better user performance and leads to greater customer satisfaction. The general rules for designing the paths of operation of an in-car infotainment system described in this project can be applied to other domains and open perspectives for future research.

Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: This study describes the design and construction of a low-cost linear Fresnel solar concentrator. Ray-trace simulation models that analyse optical performance were developed and then used to perform sensitivity analyses of various characteristics of linear Fresnel concentrators. The design of a small-scale concentrator was optimised using the simulation models, after which the concentrator was constructed in the solar laboratory. The concentrator consists of a single-motor tracking system, flat primary mirrors and a low-cost secondary concentrator that approximates a compound parabolic concentrator. Testing revealed satisfactory performance that was comparable to the simulation models’ prediction. The construction of a low-cost solar concentrator that can replace existing thermal sources for the generation of power and process heat is thus achievable. / AFRIKAANSE OPSOMMING: Die ontwerp en konstruksie van 'n laekoste- lineêre Fresnel-sonkonsentreerder word in hierdie studie beskryf. Stralingsimulasiemodelle wat optiese werksverrigting analiseer is ontwikkel en gebruik om sensitiwiteitsanalises van die verskillende eienskappe van lineêre Fresnel-konsentreerders te doen. Die modelle is verder gebruik om die ontwerp van 'n kleinskaalse konsentreerder te optimeer, waarna die konsentreerder in die sonlaboratorium gebou is. Die konsentreerder bestaan uit 'n enkelmotorvolgingstelsel, plat primêre spieëls en 'n laekoste- sekondêre konsentreerder soortgelyk aan 'n saamgestelde, paraboliese konsentreerder. Toetsing dui bevredigende werksverrigting aan, vergelykbaar met wat die simulasiemodelle voorspel het. Dit is dus moontlik om 'n laekoste-sonkonsentreerder wat bestaande termiese bronne vir kragopwekking en proseshittegenerasie kan vervang, daar te stel.

A travers l’exemple himalayen, nous étudions les mécanismes influençant la composition en osmium des sédiments durant l’érosion, le transport sédimentaire et le dépôt dans les zones estuariennes. Au niveau du bassin himalayen de la Kali Gandaki, les relations observées entre les concentrations en osmium et les quantités de carbone organique confirment le rôle important des schistes noirs appartenant aux TSS (non radiogéniques) et au LH (radiogénique) malgré leurs faibles répartitions géographiques. Cependant, la composition fortement radiogénique mesurée dans les sédiments du Gange n'est pas couplée a un enrichissement en 187Os dont la quantité moyenne est comparable à celle mesurée dans la croûte continentale. La signature isotopique du Gange résulterait d'un appauvrissement en Os non-radiogénique, témoignant d'une forte dilution par des sédiments dérivés de l'érosion des roches cristallines de l'HHC. Nous montrons à travers l’étude de sédiments estuariens que le comportement de l’osmium en contact avec l’eau de mer est complexe et des échanges sont possibles à l’interface. Le développement analytique réalisé en parallèle des études sur les sédiments a permis de documenter pour la première fois la composition en osmium des eaux souterraines. L’étude des aquifères de la plaine du Bengale montre que les eaux souterraines possèdent des concentrations en osmium significativement plus élevées que les eaux de rivière ou l’eau de mer. Si ce résultat est généralisable aux aquifères mondiaux, un flux global de l’ordre de 170 kg d’osmium par an pourrait être apporté à l’océan. Cet apport est significatif et impliquerait la réévaluation du bilan océanique mondial et une diminution significative du temps de résidence de l’osmium dans les océans. Ce résultat n’est pas anodin puisqu’il pourrait en partie réconcilier le temps de résidence estimé par bilan de masse océanique et les variations glaciaires-interglaciaires observées par le rapport 187Os/188Os dans de nombreux enregistrements marins / Using the Himalayan example, this study documents the systematics controlling the osmium composition of sediments during weathering processes, sedimentary transport and sediment deposition in tidal areas. The relationships observed between osmium concentrations and organic carbon contents in sediments of the Himalayan Kali Gandaki catchment underscore the role of black shales from the TSS (mostly unradiogenic) and LH (highly radiogenic) Himalayan units, despite their limited geographic distribution. However, the highly radiogenic composition displayed by Ganges sediments is not coupled to an enrichment in 187Os in these sediments, which on average are comparable to that of typical continental crust. Instead, the Ganges radiogenic signature results from an impoverishment in non-radiogenic osmium, reflecting a strong dilution by erosion products of crystalline rocks of the HHC unit. Moreover, based on the study of rivers in the tidal zone, we document the complex behavior of osmium at the salt/fresh water transition, potentially involving exchange between sediments and dissolved osmium. Analytical development performed concurrently with the sediment studies allowed the first measurements of groundwater osmium compositions. Groundwaters of Bengal plain aquifers have osmium contents significantly higher than those previously documented for river water or seawater. If this result can be generalized to other aquifers a global osmium groundwater flux to the ocean of about 170 kg per year could be expected. This contribution is significant and would require a reevaluation of both the osmium marine budget and the residence time of osmium in the ocean. This result could partially reconcile the diverging marine Os residence times estimated from mass balance and from glacial-interglacial variations in the 187Os/188Os marine record

The main objective of the thesis is to study artificial wastewater recharge in the area of Řevničov and reassessment of related problems such as groundwater chemical changes, colmatage, and unfavorable legislation in the Czech Republic. Individual chapters describe the experience with the above mentioned topic in the Czech Republic, but classifies it into the global context. The major part of the thesis focuses on the assessment of the qualitative and quantitative impacts of wastewater artificial recharge in the geological environment. These conclusions are drawn from monitoring changes of groundwater quality, which are controlled on the network of monitoring boreholes in the Řevničov experimental catchment. The natural attenuation of geological environment has considerable impact to final composition of contaminated water, which is compared to legal limits of underground and potable water in Czech Republic. In the research area several tracing tests were also applied, with the aim of proving the expected flow of wastewater into monitoring borehole. The obtained data specify the situation in the area of interest, or may serve as a source of information for future studies dealing with similar topics. Powered by TCPDF (www.tcpdf.org)

Title: Interactive Preview Renderer for Complex Camera Models Author: Bohumír Zámečník Department: Department of Software and Computer Science Education Supervisor: Dr. Alexander Wilkie Supervisor's e-mail address: alexander@wilkie.at Abstract: An interactive renderer was implemented that allows users to preview the effects of imaging with lenses, such as depth of field, bokeh (defocus highlights) and tilt-shift lens configurations. It is based on a state-of-the-art method which com- bines the power of GPU rasterization and ray tracing. Many models and interactive visualizations were created. A non-interactive simulation of a complex geometrical lens model has been made which is able to produce optical aberrations. Also a prototype implementation of recent fast spreading filters is available. A thorough summary of the principles of optical image formation, lens models and depth of field rendering methods used in computer graphics is given along with a comparison of the approaches and new insights. New possibilities of representing the behavior of complex lenses are suggested, which could be employed to accelerate the rendering. Keywords: image synthesis, camera models, depth of field, GPU, image-based ray tracing

L'imagerie terrestre urbaine se développe grâce à la diffusion grand public de visualisateurs immersifs au niveau de la rue. L'objectif de cette thèse est de proposer une méthode physique d'estimation de la réflectance des matériaux d'une scène urbaine à partir des images d'un système mobile d'acquisition, comme par exemple le véhicule d'acquisition Stereopolis, développé au laboratoire MATIS de l'Institut National de l'Information Géographique et Forestière (IGN).Pour cela, on considère que l'on dispose d'un modèle 3D de la scène, segmenté en zones de réflectance homogène (décrite par un modèle paramétrique), d'un jeu d'images géoréférencées corrigées radiométriquement. On propose une méthode d'estimation des réflectances par minimisation de l'écart entre les images réelles acquises par le capteur et des images simulées depuis le même point de vue. Après une modélisation phénoménologique des différentes composantes de la luminance arrivant au niveau d'un capteur imageur dans le domaine visible, une méthode utilisant le lancer de rayons sert à simuler cette luminance. Cela constitue ici le problème direct. Cet outil de simulation nécessite la connaissance de l'illumination de la scène, i.e. la répartition et la puissance des sources de lumière. Pour une acquisition avec Stereopolis, on ne réalise généralement pas de mesures atmosphériques et/ou radiométriques permettant de déterminer l'illumination avec des codes de transfert radiatif ; c'est pourquoi on propose une méthode d'estimation de la luminance du ciel à partir des images, en utilisant les pixels qui voient le ciel. L'éclairement solaire direct, non accessible directement dans les images, est estimé par une méthode ombre-soleil grâce à une plaque de référence placée sur le toit du véhicule. L'algorithme d'inversion du système se fait par minimisation d'une fonction coût constituée par la différence pixel à pixel entre les images simulées avec certains paramètres de réflectance et les images réelles. Cela nécessite de nombreuses simulations par lancer de rayons, car l'algorithme est itératif en raison des réflexions multiples entre les objets qui doivent être calculées avec des paramètres de réflectances initiaux. Afin d'éviter ces très coûteux lancers de rayons, on propose un algorithme de lancer de rayons formel qui stocke la luminance simulée comme des fonctions des paramètres de réflectances au lieu d'une valeur numérique. Cela permet de mettre à jour les images de luminance simulées par simple évaluation de ces fonctions avec le jeu de paramètres courant. La minimisation elle-même est effectuée par la méthode du gradient conjugué. Des résultats sur des scènes synthétiques permettent de faire une première validation de la méthode. Cependant, l'application sur un jeu d'images issues de Stereopolis pose plusieurs difficultés, notamment liées l'étalonnage radiométrique et à la segmentation du modèle 3D utilisé en entrée / Urban terrestrial imagery is widely used through online viewers of street-level images. The MATIS of the French National Geographical and Forester Data Institute (IGN) has developed its own mobile-mapping vehicle, Stereopolis, dedicated to research purposes. In this thesis, we develop a physically-based method to retrieve the reflectance of urban materials from a set of images shot by a mobile-mapping vehicle. This method uses a 3D model of the scene (segmented in areas of homogeneous reflectance, modeled by a parametric formula) and a set of georeferenced and radiometrically corrected images. We present a method for the estimation of the reflectances of the materials by minimizing the difference between real acquired images and simulated images from the same point of view. A modelisation of the physical phenomena leading to the formation of optical images is presented. A code using ray-tracing algortihm is used to compute the radiance at the sensor level. This is the direct problem for our estimation of reflectances. The illumination of the scene must be an input of this simulation tool; now, in a typical urban mobile-mapping acquisition neither atmospheric nor radiometric measurements are performed, that could be used to determine the illumination with a radiative transfer code. We propose an estimation of the illumination using directly the sky pixels in the acquired images. The direct solar irradiance cannot be estimated from the images because of overexposure, but we can use a shadows casted on a dedicated reference plate placed on top of the vehicle. The reflectances estimation is performed by minimizing a cost function; this cost function is the pixel-wise difference between simulated images (with current reflectances parameters) and acquired images. This leads to numerous ray-tracing simulations as the algorithm is iterative due to interreflections between the objects of the scene, that are computed using initial parameters. In order to prevent these costly ray-tracing simulations, we propose a symbolic ray-tracing algorithm that computes the radiance as a symbolic function of the reflectances parameters instead of a numerical value. Then, each iteration of the minimization algorithm is only an evaluation of a symbolic function. Results are shown on synthetic scenes to perform a first validation the estimation method. Using this method on real Stereopolis images remains difficult, mainly due to the radiometric calibration of cameras and the segmentation on the 3D model