2,452 research outputs found

    Random ambience using high fidelity images

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    Most of the secure communication nowadays mandates true random keys as an input. These operations are mostly designed and taken care of by the developers of the cryptosystem. Due to the nature of confidential crypto development today, pseudorandom keys are typically designed and still preferred by the developers of the cryptosystem. However, these pseudorandom keys are predictable, periodic and repeatable, hence they carry minimal entropy. True random keys are believed to be generated only via hardware random number generators. Careful statistical analysis is still required to have any confidence the process and apparatus generates numbers that are sufficiently random to suit the cryptographic use. In this underlying research, each moment in life is considered unique in itself. The random key is unique for the given moment generated by the user whenever he or she needs the random keys in practical secure communication. An ambience of high fidelity digital image shall be tested for its randomness according to the NIST Statistical Test Suite. Recommendation on generating a simple 4 megabits per second random cryptographic keys live shall be reported

    Smart security door system using SMS based energy harvest

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    Over the last decade, different studies have been conducted to increase security to identify sensor technology and provide alternative energy with other energy harvest techniques such as vibration energy harvester and sun energy harvester. There is no combinational approach to utilize the door to create energy and use it for security measures in the literature, making our system different and unique. This proposed system comprises the security and the energy harvest; the security section utilizes a motion detector sensor to detect intruders. For instance, the magnetic door lock type firmly locks the door, which can only open with a generated password. On the other side, the energy harvest section utilizes the door motion to generate electricity for the system, which solves power shortage and limited battery life issues. Moreover, this study includes a GSM module that allows authorized owners to receive a generated password as a security enhancement. This design mainly focuses on improving or optimizing the conventional security doors' overall performance as sliding door, panel door, or revolving door. The experimental results show the system efficiency in terms of power generation and the time needed to authenticate the property owner. Notably, the power generator can generate electricity more rapidly, while the needed time to receive the mobile device's security code is around 3.6 seconds

    J3Gen : a PRNG for Low-Cost Passive RFID

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    Pseudorandom number generation (PRNG) is the main security tool in low-cost passive radio-frequency identification (RFID) technologies, such as EPC Gen2. We present a lightweight PRNG design for low-cost passive RFID tags, named J3Gen. J3Gen is based on a linear feedback shift register (LFSR) configured with multiple feedback polynomials. The polynomials are alternated during the generation of sequences via a physical source of randomness. J3Gen successfully handles the inherent linearity of LFSR based PRNGs and satisfies the statistical requirements imposed by the EPC Gen2 standard. A hardware implementation of J3Gen is presented and evaluated with regard to different design parameters, defining the key-equivalence security and nonlinearity of the design. The results of a SPICE simulation confirm the power-consumption suitability of the proposal

    Multi-algorithmic Cryptography using Deterministic Chaos with Applications to Mobile Communications

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    In this extended paper, we present an overview of the principal issues associated with cryptography, providing historically significant examples for illustrative purposes as part of a short tutorial for readers that are not familiar with the subject matter. This is used to introduce the role that nonlinear dynamics and chaos play in the design of encryption engines which utilize different types of Iteration Function Systems (IFS). The design of such encryption engines requires that they conform to the principles associated with diffusion and confusion for generating ciphers that are of a maximum entropy type. For this reason, the role of confusion and diffusion in cryptography is discussed giving a design guide to the construction of ciphers that are based on the use of IFS. We then present the background and operating framework associated with a new product - CrypsticTM - which is based on the application of multi-algorithmic IFS to design encryption engines mounted on a USB memory stick using both disinformation and obfuscation to ‘hide’ a forensically inert application. The protocols and procedures associated with the use of this product are also briefly discussed

    Development of a Kinetic Model for the Transesterification of Glycerol Fatty Acid Triesters Using \u3csup\u3e1\u3c/sup\u3eH (1D and 2D) NMR

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    Fossil fuels dating back to the first coal mine dug from the Earth have been vital to society’s advances, but have come at a significant cost. Rise in pollutants such as CO2 and particulate matter due to combustion byproducts of these fuels (coal, oil, gasoline, diesel) continue to negatively impact the environment, harming various ecosystems by disrupting precarious balances. Attempts have been made to “clean” fossil fuels, but only to temporary degrees of success. Alternative energy sources such as solar, wind, or hydroelectric are increasing in viability, but are often a difficult transition for fossil fuel reliant individuals. Biodiesel (Fatty Acid Methyl Esters, FAME) is an alternative “cleaner” fuel made from renewable vegetable oils that can be used in diesel vehicles with few to no engine modifications, easing consumer transition to alternative energy sources. Biodiesel is a possible replacement for petroleum diesel due to reduced greenhouse gas emissions, unburned hydrocarbons, carbon monoxide, particulate matter and nitrogen oxides. A diesel engine can run on an 80/20 (B20) mix of petroleum diesel to biodiesel, and with adjustments (to avoid possible clogging) can run 100% (B100) biodiesel. Biodiesel produced from vegetable (soybean) oil through a base catalyzed transesterification with methanol is, however, an inefficient and wasteful process. Our research group is applying green chemistry principles to improve the efficiency of small-scale (bench top) biodiesel production, but this work has been hindered by the lack of detailed information about the mechanism behind the transesterification reaction. Our research goal was to develop a detailed kinetic model that would identify whether rate limiting transesterification occurs at C1/3 or C2 as the glyceryl triester is converted into the di- and mono- ester, and finally free glycerol. Transesterification reactions were conducted on a 25mL scale at 60oC to test our methodology for quenching the reaction with acetone d-6, and at 25oC to acquire a time zero data point. Reaction aliquots were analyzed using quantitative NMR, employing an internal reference standard of maleic acid for concentration calculations, and integrated data was used to analyze and obtain time course data. All controls and standards gave unambiguous NMR spectra with \u3c5% error. 2D spectroscopy was also performed and will be assessed for future usefulness in determining C1/3 or C2 ester branches leaving as the limiting step. The results of this research will help narrow the options for improvements to the reaction efficiency, for example in catalyst design. This theses’ secondary goal is to develop an introduction and guidebook to cleaner fuels research and kinetic experimentation using NMR instrumentation

    Mesonische Korrelationsfunktionen aus leichten Quarks und ihre spektrale Darstellung in heißer gequenchter Gitter-QCD

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    Wissel S. Mesonic correlation functions from light quarks and their spectral representation in hot quenched lattice QCD. Bielefeld (Germany): Bielefeld University; 2006.In dieser Arbeit untersuchen wir anhand von Gittersimulationen der Quantenchromodynamik thermische in-medium Modifikationen fĂŒr unterschiedliche Mesonkorrelationsfunktionen bei leichten Valenzquarkmassen und verschwindenden chemischen Potentials. Mesonische Eigenschaften werden in der Regel anhand rĂ€umlicher Korrelationsfunktionen extrahiert. Die Ergebnisse basieren dabei auf gequenchten Eichfeldkonfigurationen, die mit Hilfe der standard Wilson Plaquette Eichwirkung erzeugt werden. BezĂŒglich des fermionischen Anteils der Wirkung verwenden wir die nicht-störungstheoretische O(a) verbesserte Sheikholeshami-Wohlert sowie eine auf den Hyperkubus trunkierte perfekte Wirkung. Ferner wird die maximale Entropie Methode verwendet, um anhand von Spektralfunktionen physikalisch relevante Polmassen zu bestimmen und thermische Modifikationen physikalischer ZustĂ€nde sowie möglicher Gitterartefakte im wechselwirkenden Fall zu untersuchen. Die Auswertung von Pol- und Screeningmassen, Dispersionsrelationen, Wellenfunktionen, Zerfallskonstanten und Spektralfunktionen hat im wesentlichen ergeben, dass wir bis 0,55 Tc keine signifikanten VerĂ€nderungen zum null Temperatur Verhalten erkennen können. Erst nahe dem PhasenĂŒbergang scheinen sich in-medium Effekte bemerkbar zu machen, was u.a. zu einer signifikanten Abweichung zwischen Pol- und Screeningmassen gefĂŒhrt hat. Die Zerfallskonstanten sind in guter Übereinstimmung mit den experimentellen Werten. Oberhalb von Tc haben wir mit einer quasi null Quarkmasse simuliert. Bei 1,24 Tc hat das Auftreten topologischer Effekte als ein Zeichen fĂŒr eine immer noch vorhandene U(1)_A Symmetriebrechung eine eingehendere Analyse in direkter NĂ€he des PhasenĂŒbergangs verhindert. Eine vollstĂ€ndige Kontinuums- und Volumen-Extrapolation der Screening Massen, orientiert an dem Verhalten freier Gitter effektiven Massen, wird durchgefĂŒhrt. Diese zeigt, dass noch vorhandene kollektive PhĂ€nomene bei 1,5 und 3 Tc nicht durch einfache Gittereffekte erklĂ€rt werden können. Anders als das Vektormeson ist das pseudoskalare Meson weit davon entfernt, ein ungebundener Zustand zu sein.In this thesis we investigate thermal in-medium modifications of various mesonic correlation functions by lattice simulations of Quantum Chromodynamics for light valence quark masses and vanishing chemical potential. Mesonic properties are typically extracted from spatial correlation functions. The results presented are based on quenched gauge field configurations generated with the standard Wilson plaquette gauge action. Concerning the fermionic part of the action, we use the non-perturbative O(a) improved Sheikholeslami-Wohlert as well as the truncated hypercube perfect action. Furthermore we utilize the maximum entropy method in order to determine physically relevant pole masses and to investigate thermal modifications of physical states and possible lattice artefacts in the interacting case. The analyses of pole and screening masses, dispersion relations, wave functions, decay constants and spectral functions essentially yield no significant modifications of the zero-temperature behavior up to 0.55 Tc. Close to the phase transition in-medium effects seem to appear, which lead inter alia to significant differences between pole and screening masses. The decay constants are in good agreement with the experimental values. We have simulated above Tc at nearly zero quark masses. At 1.24 Tc, the occurrence of topological effects, a sign for the presence of a still broken U(1)_A symmetry, prevent a more thorough analyses close to the phase transition. A complete continuum and infinite volume extrapolation of screening masses, guided by free lattice effective masses is done. It shows that the presence of collective phenomena at 1.5 and 3 Tc cannot be explained by pure lattice artefacts. Unlike the vector meson the pion is far from being considered an unbound state

    Are Thermal Attacks Ubiquitous? When Non-Expert Attackers Use Off the Shelf Thermal Cameras

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    Recent work showed that using image processing techniques on thermal images taken by high-end equipment reveals passwords entered on touchscreens and keyboards. In this paper, we investigate the susceptibility of common touch inputs to thermal attacks when non-expert attackers visually inspect thermal images. Using an off-the-shelf thermal camera, we collected thermal images of a smartphone's touchscreen and a laptop's touchpad after 25 participants had entered passwords using touch gestures and touch taps. We show that visual inspection of thermal images by 18 participants reveals the majority of passwords. Touch gestures are more vulnerable to thermal attacks (60.65% successful attacks) than touch taps (23.61%), and attacks against touchscreens are more accurate than on touchpads (87.04% vs 56.02%). We discuss how the affordability of thermal attacks and the nature of touch interactions make the threat ubiquitous, and the implications this has on security
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