Time-driven Discrete-event Simulator for Controller Area Networks

Computer Science

Physically Uncloneable Functions in the Stand-Alone and Universally Composable Framework

In this thesis, we investigate the possibility of basing cryptographic primitives on Physically Uncloneable Functions (PUF). A PUF is a piece of hardware that can be seen as a source of randomness. When a PUF is evaluated on a physical stimulus, it answers with a noisy output. PUFs are unpredictable such that even if a chosen stimulus is given, it should be infeasible to predict the corresponding output without physically evaluating the PUF. Furthermore, PUFs are uncloneable, which means that even if all components of the system are known, it is computational infeasible to model their behavior. In the course of this dissertation, we discuss PUFs in the context of their implementation, their mathematical description, as well as their usage as a cryptographic primitive and in cryptographic protocols. We first give an overview of the most prominent PUF constructions in order to derive subsequently an appropriate mathematical PUF model. It turns out that this is a non- trivial task, because it is not certain which common security properties are generally necessary and achievable due to the numerous PUF implementations. Next, we consider PUFs in security applications. Due to the properties of PUFs, these hardware tokens are good to build authentication protocols that rely on challenge/response pairs. If the number of potential PUF-based challenge/response pairs is large enough, an adversary cannot measure all PUF responses. Therefore, the at- tacker will most likely not be able to answer the challenge of the issuing party even if he had physical access to the PUF for a short time. However, we show that some of the previously suggested protocols are not fully secure in the attacker model where the adversary has physical control of the PUF and the corresponding reader during a short time. Finally, we analyze PUFs in the universally composable (UC) framework for the first time. Although hardware tokens have been considered before in the UC framework, designing PUF-based protocols is fundamentally different from other hardware token approaches. One reason is that the manufacturer of the PUF creates a physical object that outputs pseudorandom values, but where no specific code is running. In fact, the functional behavior of the PUF is unpredictable even for the PUF creator. Thus, only the party in possession of the PUF has full access to the secrets. After formalizing PUFs in the UC framework, we derive efficient UC-secure protocols for basic tasks like oblivious transfer, commitments, and key exchange

Assessment of color quality and energy effciency : new insights for modern lighting. Part I : color quality in general lighting applications. Part II : mesopic photometry and street lighting

This dissertation is divided in two parts: The first one deal with two main characteristics of the light sources for general lighting: Color quality and luminous efficacy. The second one deals with technical aspects of the mesopic photometry applied in street lighting. The first part begins by proposing a method to generate a new color rendering index, consisting of a three-dimensional visual index, which was named 3D-CRM. In order to illustrate the use of this method and index, three examples of lighting application were performed: Artwork, meat and fruit. The results show the goodness of the visual index 3D-CRM, that is also accompanied by a numeric index that indicates how the light source tested fits with the gamut of colors required by the specific lighting application. Complementing the preceding proposal, a statistical analysis was performed in order to define the parameters that make up the color quality of light sources. This statistical study was based on a collection of more than 100 real and ideal spectra of light sources. As a result, it was found that there is another variable that can complement the CRI index to indicate the color quality. This is the proposed index Oc (Optimal Color), which is based on the calculation of volumes generated with the spectrum of test source and several ideal spectra of reflectance to get optimal colors (high saturated colors) at different luminance levels. This fisrt part of the dissertation ends by proposing an index to generate a classification of light sources according to the requirements of the lighting application and the parameters such as correlated color temperature (CCT), luminous efficacy of radiation (LER) and color quality (CQ). It was demonstrated that the new proposed index called ECQ (Efficacy and Color Quality), is able to generate a useful ranking when assessing a collection of spectra, by giving a desired CCT and the weight that efficacy and color quality have in the lighting application studied. By using some examples of different lighting applications (i.e. different weights for color quality and efficacy) it was demonstrated how versatile and useful the ECQ index is. In the second part of this dissertation, a comparison of laboratory measurements between two different types of goniophotometers is made. The first one is a standard and photometer-based one, which uses the far-field for measurement. The second one has a more recent technology, uses a CCD camera and photometer as sensors, as well as the near field for measurement. This comparison exercise validates the measurements from the near-field goniophotometer, since up to moment, for this type of measurement and type of sensor (CCD camera), there are no laboratories with international traceability that can verify or calibrate this measurement system. The comparison exercise shows that there is a very good fit between both measures performed to standard light bulbs; therefore results of the near-field goniophotometer are validated. In recent measures performed at the Light and lighting laboratory of K.U. Leuven in Ghent, it was found that near field goniophotometer has a reduced luminous intensity dynamic range, for this reason exists an error measuring low luminous intensities in a luminarie with a sharp LID such as PAR30 Spot light bulb. After that, some aspects of the Recommended System for Mesopic Photometry Based on Visual Performance, CIE191:2010 are analysed. Finally it is presented a proposal of a new metrics called Energy Consumption Index (Qsa) intended to assessing possible energy savings on street lighting systems. In this chapter, by using the Energy Consumption Index an evaluation of three different hypothetical scenarios for a typical city is performed to demonstrate how flexible and intuitive this index is. These scenarios assess different characteristics of the light system such as light sources types, dimming systems and also the use of photopic and mesopic photometry.Esta tesis se divide en dos partes: La primera trata con dos características principales de las fuentes de luz para la iluminación general: la calidad del color y de eficacia luminosa. El segundo se ocupa de los aspectos técnicos de la fotometría mesópica aplicada en el alumbrado público. La primera parte comienza proponiendo un procedimiento para generar un nuevo índice de rendimiento de color, que consiste en un índice visual tridimensional, llamado 3D-CRM. Con el fin de ilustrar el uso de este índice, se realizaron tres ejemplos de aplicación de iluminación: Arte, carnes y frutas. Los resultados muestran la bondad del índice visual 3D-CRM, que también se acompaña de un índice numérico que indica que tan bien una fuente de luz bajo prueba repolores la gama de colores para una aplicación de iluminación específica. Como complemento de la propuesta anterior, se realizó un análisis estadístico con el fin de definir los parámetros que componen la calidad de color de fuentes de luz. Este estudio estadístico se basa en una colección de más de 100 espectros reales e ideales de fuentes de luz. Como resultado, se encontró que hay otra variable que puede complementar el índice CRI para indicar la calidad del color. Este es el índice propuesto Oc (óptima del color), que se basa en el cálculo de los volúmenes generados con el espectro de la fuente de prueba y varios espectros ideal de reflectancia para obtener colores óptimos (colores de alta saturación) a diferentes niveles de luminancia. Esta primera parte termina proponiendo un índice para generar una clasificación de las fuentes de luz de acuerdo con los requisitos de la aplicación de iluminación y los parámetros tales como la temperatura de color correlacionada (CCT), la eficacia lumínica de radiación (LER) y la calidad de color (CQ ). Se demostró que el nuevo índice propuesto llamada ECQ (eficacia y calidad del color), es capaz de generar una clasificación útil en la evaluación de una colección de espectros, dando un CCT deseado y el peso que la eficacia y la calidad del color tienen en la aplicación de iluminación estudiado . Mediante el uso de algunos ejemplos de diferentes aplicaciones de iluminación (es decir, diferentes pesos para la calidad del color y la eficacia lumínica) se demostró la versatilidad y utilidad de este indicador. En la segunda parte de esta tesis, se hace una comparación de mediciones de laboratorio entre dos tipos diferentes de Goniofotómetros. El primero es uno estándar basada en el fotómetro, que utiliza el campo lejano para la medición. El segundo tiene una tecnología más reciente, utiliza una cámara CCD y fotómetro como sensores, así como el campo cercano para la medición. Este ejercicio de comparación valida las mediciones de la goniofotómetro de campo cercano, ya que hasta el momento, para este tipo de medición y el tipo de sensor (cámara CCD), no hay laboratorios con trazabilidad internacional que puede verificar o calibrar este sistema de medición. El ejercicio de comparación muestra que hay un muy buen ajuste entre las dos medidas realizadas a las bombillas estándar; Por lo tanto, los resultados del Goniofotómetro de campo cercano se validan. En recientes medidas realizadas en el laboratorio de luz e iluminación de K.U. Lovaina en Gante, se encontró que Goniofotómetro de campo cercano tiene un rango dinámico limitado para medición de intensidad luminosa, por esta razón existe un error de medición de bajas intensidades luminosas en una luminaria con una distribución aguda como por ejemplo un proyector de luz. Posteriormente se analizan, algunos aspectos del sistema recomendado para fotometría mesópica basado en el rendimiento visual, CIE191: 2010. Por último se presenta una propuesta de una nueva métrica llamada Índice de Consumo de Energía (Qsa) destinado a evaluar los posibles ahorros de energía en los sistemas de alumbrado públic

A computer-aided design for digital filter implementation

Imperial Users onl

Analysis of design strategies for RF ESD problems in CMOS circuits

This thesis analyses the design strategies used to protect RF circuits that are implemented in CMOS technologies. It investigates, in detail, the physical mechanisms involved when a ggNMOS structure is exposed to an ESD event and undergoes snapback. The understanding gained is used to understand why the performance of the current RF ESD clamp is poor and suggestions are made as to how the performance of ggNMOS clamps can be improved beyond the current body of knowledge. The ultimate aim is to be able to design effective ESD protection clamps whilst minimising the effect the circuit has on RF I/O signals. A current ggNMOS based RF ESD I/O protection circuit is analysed in detail using a Transmission Line Pulse (TLP) tester. This is shown to be a very effective diagnostic tool by showing many characteristics of the ggNMOS during the triggering and conducting phase of the ESD event and demonstrate deficiencies in the clamp design. The use of a FIB enhances the analysis by allowing the isolation of individual components in the circuit and therefore their analysis using the TLP tester. SPICE simulations are used to provide further commentary on the debate surrounding the specification required of a TLP tester for there to be a good correlation between a TLP test and the industry standard Human Body Model (HBM) ESD test. Finite element simulations are used to probe deeper in to the mechanisms involved when a ggNMOS undergoes snapback especially with regard to the contribution parasitic components within the ggNMOS make to the snapback process. New ggNMOS clamps are proposed which after some modification are shown to work. Some of the finite element experiments are repeated in a 0.18μπ7. process CMOS test chip and a comparison is made between the two sets of results. In the concluding chapter understanding that has been gained from previous chapters is combined with the published body of knowledge to suggest and explain improvements in the design of a ggNMOS for RF and standard applications. These improvements will improve homogeneity of ggNMOS operation thus allowing the device size to be reduced and parasitic loading for a given ESD performance. These techniques can also be used to ensure that the ESD current does not take an unintended path through the chip

AN ENERGY EFFICIENT CROSS-LAYER NETWORK OPERATION MODEL FOR MOBILE WIRELESS SENSOR NETWORKS

Wireless sensor networks (WSNs) are modern technologies used to sense/control the environment whether indoors or outdoors. Sensor nodes are miniatures that can sense a specific event according to the end user(s) needs. The types of applications where such technology can be utilised and implemented are vast and range from households’ low end simple need applications to high end military based applications. WSNs are resource limited. Sensor nodes are expected to work on a limited source of power (e.g., batteries). The connectivity quality and reliability of the nodes is dependent on the quality of the hardware which the nodes are made of. Sensor nodes are envisioned to be either stationary or mobile. Mobility increases the issues of the quality of the operation of the network because it effects directly on the quality of the connections between the nodes

Stock Market Simulation

During this project the group performed a ten-week stock market simulation in which they experimented with different investing strategies to learn how to navigate the stock market. They researched six different investing and trading methods in order to better understand investing. The experience gained from this project will help them become better investors in the future and help them manage their personal finances wisely

A LiDAR Based Semi-Autonomous Collision Avoidance System and the Development of a Hardware-in-the-Loop Simulator to Aid in Algorithm Development and Human Studies

In this paper, the architecture and implementation of an embedded controller for a steering based semi-autonomous collision avoidance system on a 1/10th scale model is presented. In addition, the development of a 2D hardware-in-the-loop simulator with vehicle dynamics based on the bicycle model is described. The semi-autonomous collision avoidance software is fully contained onboard a single-board computer running embedded GNU/Linux. To eliminate any wired tethers that limit the system’s abilities, the driver operates the vehicle at a user-control-station through a wireless Bluetooth interface. The user-control-station is outfitted with a game-controller that provides standard steering wheel and pedal controls along with a television monitor equipped with a wireless video receiver in order to provide a real-time driver’s perspective video feed. The hardware-in-the-loop simulator was developed in order to aid in the evaluation and further development of the semi-autonomous collision avoidance algorithms. In addition, a post analysis tool was created to numerically and visually inspect the controller’s responses. The ultimate goal of this project was to create a wireless 1/10th scale collision avoidance research platform to facilitate human studies surrounding driver assistance and active safety systems in automobiles. This thesis is a continuation of work done by numerous Cal Poly undergraduate and graduate students

Sparse aperture imaging satellite

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2002.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 213-217).The quest for higher angular resolution in astronomy will inevitably lead to larger and larger apertures. Unfortunately, the diameter size of primary mirrors for space telescopes is limited by the volume and mass constraints of current launch vehicles as well as the scaling laws of manufacturing costs. Efforts are ongoing to break this trend by employing exotic technologies such as deployed segmented mirror telescopes, and sparse aperture optics using interferometry. In order to better understand the technological difficulties involved in designing and building a sparse aperture array, the challenge of building a white light Golay-3 telescope was undertaken. The MIT Adaptive Reconnaissance Golay- 3 Optical Satellite (ARGOS) project exploits wide-angle Fizeau interferometer technology with an emphasis on modularity in the optics and spacecraft subsystems. Unique design procedures encompassing the nature of coherent wavefront sensing, control and combining as well as various systems engineering aspects to achieve cost effectiveness, are developed. To demonstrate a complete spacecraft in a 1-g environment, the ARGOS system is mounted on a frictionless air-bearing, and has the ability to track fast orbiting satellites like the ISS or the planets. Wavefront sensing techniques are explored to mitigate initial misalignment and to feed back real-time aberrations into the optical control loop. This paper presents the results and the lessons learned from the conceive, design and implementation phases of ARGOS. A preliminary assessment shows that the beam combining problem is the most challenging aspect of sparse optical arrays. The need for optical control is paramount due to tight beam combining tolerances. The wavefront sensing/control requirements appear to be a major technology and cost driver.by Soon-Jo Chung.S.M