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The Large Hadron Collider (LHC) and the four major experiments set up along its 27 kilometers of circumference (ATLAS, CMS, ALICE and LHCb), have recently started to explore the high–energy frontier at √s = 8 TeV, and will move to even higher energy in just about 2 years. The aim of physics searches at LHC experiments was to complete the picture of the Standard Model (SM) of elementary particles with the discovery of the Higgs boson and to look for specific signatures of models extending the current understanding of particle interactions, at zero and non–zero temperature. In 2012, the official discovery of the Higgs boson, the only missing particle of the StandardModel, was announced by ATLAS and CMS. Other important results include the measurement of rare decay modes in heavy quarks systems, and indications of CP violation in charm decays by LHCb. Signatures of beyond the Standard Model (BSM) physics are currently being looked for in the experimental data, and this often requires the knowledge of quantities that can be computed only with non–perturbative methods. This thesis focuses on some possible extensions of the SM and the analysis of interesting physical observables, like masses or decay rates, calculated using non– perturbative lattice methods. The approach followed for the main part of this work is to model BSM theories as effective field theories defined on a lattice. This lattice approach has a twofold advantage: it allows us to explore non– renormalizable gauge theories by imposing an explicit gauge–invariant cutoff and it allows us to go beyond perturbative results in the study of strongly interacting systems. Some of the issues of the SM that we will try to address include, for example, the hierarchy problem and the origin of dynamical electroweak symmetry breaking (DEWSB). We investigate non–perturbatively the possibility that the lightness of the mass for an elementary scalar field in a four–dimensional quantum field theory might be due to a higher–dimensional gauge symmetry principle. This idea fits in the Gauge–Higgs unification approach to the hierarchy problem and the results we present extend what is known from perturbative expectations. Extra dimensional models are also often used to approach DEWSB. Another approach to DEWSB implies a new strongly interacting gauge sector that extends the SM at high energies and it is usually referred to as Technicolor. The phenomenological consequences of Technicolor can only be studied by non– perturbative methods at low energy since the theory is strongly coupled at large distances. We perform a comprehensive lattice study of fermionic and gluonic scalar bound states in one of the candidate theories for Technicolor BSM physics. We relate our findings to the nature of the newly discovered Higgs boson. New physics is also commonly believed to be hidden in the flavour sector of the SM. In this sector, lattice calculations of non–perturbative input parameters are needed in order to make precise predictions and extract signals of possible new physics. In particular, heavy quark physics on the lattice is still in development and it is important to understand the relevant discretisation errors. We describe a preliminary study of the mixing parameter of heavy–light mesons oscillations in a partially–quenched scenario, using staggered dynamical fermions and domain wall valence fermions.

This thesis presents the detailed measurements of the tracking efficiency of the BaBar detector using T pair events. These efficiency measurements are critical for many physics analyses at BaBar. The tracking efficiency is dctcrmined both as a global valuc for the detector and in terms of the parameters on which the BaBar tracking reconstruction software depends. In addition, the charge asymmetry of the tracking efficiency as well as a detailed analysis of the systematic uncertainties related to this method are also presented. It was discovered that the sample of data conventionally used by BaBar for measuring the efficiency is contaminated by background and a ncw protocol for measuring thc cfficicncies is presented. Undcr this new protocol, the global tracking efficiency correction factor and the global tracking efficiency charge asymmetry are determined to be consistent with zero. A new method for determining the efficiency as a function of the reconstruction parameters, was also successfully demonstrated.

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Approved for public release, distribution is unlimited / With the rapid employment of wireless networks commercially, the military is seeking viable solutions for providing high-speed wireless network throughout the battle space. The IEEE 802.11a wireless LAN presents an attractive solution pro-viding up to 54 Mbps data-link bandwidth. Moreover, it operates in the less congested 5-GHz U-NII band and possesses more operating channels. This research implemented two prototype systems using low-cost commercially available hardware. The Cisco Ai-ronet 1400 wireless bridge and the Proxim Tsunami MP. 11a wireless system were chosen for their superior specifications and for their reputation of being market leaders in IEEE 802.11 wireless products. The performances of the prototype systems were evaluated in three operational environments (land, water and vegetation). The data collected were then compared to the theo-retical performance. / Civilian, Ministry of Defense, Singapore

Approved for public release; distribution is unlimited / Wireless networks can be broadly classified into two types - infrastructure based networks and ad hoc networks. The former uses fixed base stations (infrastructure) which are responsible for coordinating communication between the mobile hosts (nodes). These base stations are interconnected by wired back bones, where as mobile nodes communicate with the base station through the wireless media. The latter one consists of mobile nodes which communicate with each other through wireless medium without any fixed infrastructure. Hence there is no centralized infrastructure that takes care of the routing of information among the participants in the network. There has been a growing interest in ad hoc network in recent years as mobile devices have become more powerful and are capable of processing data like their desktop counterparts. When such a capability is available these devices should be able to share information among them without reliance on existing network infrastructure. Mobile devices are self configurable into either infrastructure or ad hoc mode. Protocols and software have been developed to enable mobile devices to connect to an infrastructure node, where as the same is not the case in the ad hoc environment. Host mobility causes frequent and unpredictable topological changes in a wireless environment. Finding and maintaining routes in ad hoc networks is a non trivial task. This thesis will develop software components that will enable communication in an ad hoc network. These components could be used to build collaborative services in such and ad hoc (802.11) wireless environment. / Major, Indian Air Force

In the first part of the thesis, theoretical uncertainties of jet cross-section have been calculated for proton-proton collision at the center of mass energy of 8 TeV. For jet identification the anti-kT algorithm with scale parameter R = 0.6 was used. As the calculations showed, the major contribution to the total theoretical uncertainty comes from the uncertainty of parton distribution function parameters. In the second part of the thesis, the angular distribution of dijet events produced in proton-proton collisions at the center of mass energy 8 TeV were simulated using Pythia 8 Monte Carlo event generator. New physics model of quark compositeness that should manifest itself by quark contact interaction was studied using angular distribution of dijet events. Three angular variables were discussed and these variables were used to calculate 95% CL lower limit on contact interaction scale. The results were compared and it emerged that the sensitivity to contact interaction signals varies for these variables.

Approved for public release; distribution is unlimited. / The Institute of Electrical and Electronics Engineers' new 802.16 standard is set to revolutionize the delivery of Broadband Wireless Access (BWA), much as the 802.11 "Wi-Fi" standard transformed wireless access to Local Area Networks. The standard describes a set of Medium Access Controls (MAC) and Air Interfaces that cover a broad range of broadcast frequencies and applications. As a result, manufacturers are developing 802.16 compliant equipment for high speed point-to-point circuits and point-to-multipoint circuits dubbed Wireless Metropolitan Area Networks (WMANs). These networks can span several miles and contain hundreds of subscribers. Shortly after 802.11 "Wi-Fi" systems became widespread, several serious Denial of Service (DoS) vulnerabilities inherent to the standard were discovered. This thesis examines the MAC layer of the 802.16 standard to determine whether these types of denial of service vulnerabilities are also present in the new standard. Also examined are vulnerabilities that may be unique to the 802.16 standard. / Lieutenant, United States Navy

Master of Science / Food Science / Randall K. Phebus / Campylobacter is recognized as a leading cause of bacterial gastroenteritis. In the United States, Campylobacter causes an estimated 600,000 illnesses and 55 deaths each year at a cost of over $1.3 billion. It is estimated that 80 percent of Campylobacter infections are foodborne with almost 50 percent of these cases attributed to poultry. Based on these statistics, Campylobacter and poultry is considered by some to be the riskiest pathogen-food combination. Campylobacter illness is usually self-limiting but serious illness and complications can occur. Serious illness requires treatment with antibiotics, but with emerging antibiotic resistance observed in Campylobacter isolates, treatment options might be limited. Therefore, it is of importance to reduce significantly the consumer’s exposure to Campylobacter through poultry consumption. In July 2011, USDA FSIS’s new performance standard for Campylobacter in chicken and turkey slaughter establishments went into effect. For chicken, the standard allows no more than eight Campylobacter-positive samples out of a fifty-one sample set. Methods for Campylobacter detection and enumeration include direct plating using a medium such as Campy-Cefex, MPN techniques, ELISA, and PCR. To meet the new performance standard the industry will need to consider improvements in poultry production. Improvements likely will not be limited to processing interventions such as scalding, picking, evisceration, and chilling. Improvements may include on-farm interventions such as enhanced biosecurity, use of competitive exclusion or vaccinations, good hygiene practices, and improved staging at introduction to processing. Post-processing interventions that might be considered include freezing or further processing (i.e. cooking) of poultry products from Campylobacter-positive flocks. Significant improvements in establishments’ food safety programs are expected to occur to meet the standard and are predicted to result in an estimated reduction of 5,000 Campylobacter illnesses per year.