Quantum state discrimination is a fundamental problem in quantum information science. We investigate the optimal distinguishability of orthogonal two-qubit (bipartite) quantum states. The scenario consists of three parties: Alice, Bob, and Charlie. Charlie prepares one of two orthogonal states and sends one qubit to Alice and the other to Bob. Their goal is to correctly identify which state Charlie sent. In most state discrimination scenarios, it is assumed that Alice and Bob can freely communicate with one another so as to collectively agree on the best guess. In this research, we consider a more restricted setting where only one-way classical communication is possible from Alice to Bob. Under this setting, we study two figures of merit (i) Alice's optimal probability, $P$, of identifying the state , and (ii) Alice's optimal probability, $P^\perp$, of identifying the state along with helping Bob identify the state perfectly. We show that in general $P\neq P^\perp$ and we prove a theorem for when $P=P^\perp$. We also found that the maximum of $P-P^\perp$ can arbitrarily approach $1/2$.

xvi, 119 p. ; ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / This dissertation describes the development of an apparatus that can accommodate many atom-optics experiments, as well as an experimental demonstration of an optical one-way barrier for neutral atoms. The first part of this dissertation describes in detail the design and implementation of our apparatus. The experiment setup consists of optical systems, vacuum systems, imaging systems, and the related electronics. It is designed to be versatile enough for many cold-atom experiments, including the demonstration of an optical one-way barrier for neutral atoms, quantum measurement on the single-atom level, and the study of quantum chaos using Bose-Einstein condensates. The second part of this thesis presents the experimental study of an optical one-way barrier for neutral atoms. We demonstrated an asymmetric optical potential barrier for ultracold 87 Rb atoms. The atoms are confined in a far-detuned dipole trap consisting of a single focused Gaussian beam from a fiber laser. The optical one-way barrier consists of two focused laser beams oriented nearly normal to the dipole-trap axis and tuned near the 87 Rb D 2 transition. The first beam (main barrier beam) is tuned to work as either a potential well or barrier, depending on the state of the incident atoms. The second beam (repumping barrier beam) pumps the atoms to the barrier state on the reflecting side. We investigated the transmission and reflection dynamics of the atoms in the presence of the one-way barrier, and we verified its capability for increasing the phase-space density of a sample of neutral atoms using the one-way barrier. Our experiment is a realization of Maxwell's demon and has important implications for cooling atoms and molecules not susceptible to the standard laser-cooling techniques. / Adviser: Daniel A. Steck

Radio networks are expanding, becoming more advanced, and pushing the limits of what is possible. Services utilizing the radio networks are also being developed in order to provide new functionality to end-users worldwide. When discussing 5G radio networks, concepts such as driverless vehicles, drones and near zero communication delay are recurrent. However, measures of delay are needed in order to verify that such services can be provided -- and measuring this is an extensive task. Ericsson has developed a platform for simulating a radio environment surrounding a radio base station. Using this simulator, this project involved measuring one-way packet delay in a radio network, and performing a Quality of Service evaluation of a radio network with a number of network applications in concern. Application data corresponding to video streams, or Voice over IP conversations, were simulated and packet delay measurements were used to calculate and evaluate the Quality of Service provided by a radio network. One of the main conclusions of this project was that packet delay variations are asymmetric in uplink, which suggests usage of non-conventional jitter measurement techniques.

With the increase in mobile broadband services the operators are gaining profits by providing high speed Internet access over the mobile network. On the other side they are also facing challenges to give QoS guarantee to the customers. In this thesis we investigate the impact of data rate and payload size on One Way Delay (OWD) and packet loss over TCP performance in 3G networks. Our goal is to evaluate the OWD and packet loss characteristics with respect to payload size and data rate from the collected network level traces. To collect these traces an experimental testbed is setup with Endace Data Acquisition and Generation (DAG) cards, for accurate measurements Endace DAG cards together with Global Positioning System (GPS) synchronization is implemented. The experiments are conducted for three different Swedish mobile operator networks and further the statistics of OWD measurements and packet loss for different data rates and payload sizes are evaluated. Our results indicate that the minimal OWD occurred at higher data rates and also shows a high delay variability. The packet loss has much impact on higher data rates and larger payload sizes, as the packet loss increases with the increase in data rate and payload size.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-07-12T13:37:34Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Master_Dissertation___Performance_Measurements_and_Analysis_of_Bluetooth_Low_Energy (8).pdf: 8669109 bytes, checksum: cb0af886f0cdc7babced229049a33535 (MD5) / Made available in DSpace on 2017-07-12T13:37:34Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Master_Dissertation___Performance_Measurements_and_Analysis_of_Bluetooth_Low_Energy (8).pdf: 8669109 bytes, checksum: cb0af886f0cdc7babced229049a33535 (MD5) Previous issue date: 2016-05-17 / The Internet of Things (IoT) paradigm has been rapidly gaining ground in the academic and industry communities as one of the most important emerging technologies. Some wireless communication technologies such as Bluetooth Low Energy (BLE) have been pointed as key technologies that will drive IoT applications. In order to leverage the BLE technology in IoT applications and identify the niche of applications this technology is more suitable, it is essential we have a deep understanding regarding some features such as link capacity, data transfer delay, connection establishment latency, and power consumption. This work evaluates the networking capabilities from BLE in scenarios of data transfer and connection establishment. The metrics maximum throughput, one-way delay, round-trip time, and connection establishment latency are evaluated through experimental measurements and we investigate how some factors (e.g. connection interval, pairing, packet size) impact on these metrics. Finally, this work proposes analytical models for the metrics investigated. / O paradigma da Internet das Coisas (Internet of Things - IoT) tem recebido grande destaque tanto das comunidades científicas como da indústria nos últimos anos. Algumas tecnologias de comunicação sem fio como Bluetooth Low Energy (BLE) tem sido apontadas como tecnologias que terão um papel fundamental na concepção de aplicativos de IoT. Um entendimento profundo de algumas características da tecnologia, como vazão e atraso na transmissão de dados, latência no estabelecimento de conexão e consumo de energia, é essencial para explorar ao máximo a tecnologia em cenários de IoT e identificar o nicho de aplicação onde esta tecnologia é mais aplicável. Este trabalho apresenta uma avaliação de desempenho da tecnologia BLE em cenários de transmissão de dados e estabelecimento de conexão. As métricas vazão máxima, atraso fim-a-fim, atraso ida-e-volta (Round-Trip Time - RTT) e latência de estabelecimento de conexão são avaliadas através de experimentos. Este trabalho também investiga como alguns fatores, como intervalo de conexão, encriptação de link e tamanho de pacote, impactam nas métricas avaliadas. Por fim, este trabalho apresenta modelos analíticos para as métricas investigadas.

<p>With the increased use of social media as a marketing tool, marketing strategies and the way brands communicate with customers is changing. Due to its low cost and characteristic short length of messages, Twitter is an especially beneficial marketing tool. Twitter is free and consists of making posts that are easy to compose and easy to consume, which makes it an ideal way for companies, such as startups, to reach customers without having to use many resources. However, companies should be strategic in their use of Twitter and no data exists on the best practices for startup companies as they develop Twitter marketing plans. This study sought to address this issue and explored different methods for engaging followers and which of these methods were the most effective for technology-oriented startups to use. A content analysis revealed that engagement tools, such as media, hashtags, URLs, and mentions serve their intended purpose for tech startups and were related to engagement. However, using conversational, two-way communication, as suggested by marketing companies and literature, proved to not be positively related to engagement rates. One-way, promotional language that is typically advised against was more related to higher engagement. Thus, startup tech companies should continue to prioritize engaging followers with engagement tools but should focus on non-conversational topics, such as their products, events, news, and updates.</p>

In this work, the problem of relay selection and resource power allocation in one- way and two-way cognitive relay networks using half duplex channels with different relaying protocols is investigated. Optimization problems for both single and multiple relay selection that maximize the sum rate of the secondary network without degrading the quality of service of the primary network by respecting a tolerated interference threshold were formulated. Single relay selection and optimal power allocation for two-way relaying cognitive radio networks using decode-and-forward and amplify-and-forward protocols were studied. Dual decomposition and subgradient methods were used to find the optimal power allocation. The transmission process to exchange two different messages between two transceivers for two-way relaying technique takes place in two time slots. In the first slot, the transceivers transmit their signals simultaneously to the relay. Then, during the second slot the relay broadcasts its signal to the terminals. Moreover, improvement of both spectral and energy efficiency can be achieved compared with the one-way relaying technique. As an extension, a multiple relay selection for both one-way and two-way relaying under cognitive radio scenario using amplify-and-forward were discussed. A strong optimization tool based on genetic and iterative algorithms was employed to solve the 
formulated optimization problems for both single and multiple relay selection, where discrete relay power levels were considered. Simulation results show that the practical and low-complexity heuristic approaches achieve almost the same performance of the optimal relay selection schemes either with discrete or continuous power distributions while providing a considerable saving in terms of computational complexity.

We have found an operation between permutations in the symmetric group Sn upon which we have experimentally derived results that can be linked to desirable properties in cryptography, mainly in the domain of one-way functions. From it, we have implemented a beta version of an algorithm for a hashing function by exploiting the operation’s low computational cost for speed and its properties for security. Its design makes it resistant to length extension attacks and the encoding of blocks into permutations suggests that any differential cryptanalysis technique that is based on bit conditions should be useless against it. More precisely, when measuring the evolution of differences in the compression function, bit-based distances such as the exclusive-or distance should be replaced by another type of distance, still to be determined in future research. In this work we will present the algorithm and introduce a new framework of cryptanalysis for collision and preimage attacks in order to somehow measure its security. Once this is done, we will run comparison tests against MD5 and SHA256 in order to externally evaluate our algorithm in terms of speed, weaknesses and strength.

A series of research studies have recently identified an issue called strain localization in welded wire reinforced (WWR) members. This phenomenon reportedly concentrates strains at welded cross wire locations and severely limit ductility. Those that identified the phenomenon used it to imply that WWR is unsafe because it does not warn of failure. This dissertation is investigating details to mitigate the strain localization effect and demonstrate the WWR can be used safely. A moment curvature analysis is developed using Response2000 program and calibrated using experimental data. Parametric study was developed to present a recommendation of details and minimum reinforcement required for WWR slabs. The effect of different types of WWR coating on mechanical properties were investigated. The dissertation next examined the effects of strain rate on the mechanical properties of WWR and traditional rebar. In total, fifty four slabs have been constructed using WWR and rebar with various cross wire spacing, using a realistic design. The strain localization phenomenon was not demonstrated, but WWR slabs are somewhat less ductile than traditionally reinforced members. The WWR members were shown to provide adequate ductility for warning of impending failure visually and with a well-accepted ductility measure. The WWR members were also shown the ability of load redistribution. The effect of coating demonstrates that both galvanizing WWR and coating WWR with epoxy has a positive effect on mechanical properties, along with adding corrosion resistance. The effect of strain rate shows that increase in loading rate tend to increase the yield and ultimate stresses and percent area reduction, however the loading rate increase does not have a significant effect on elastic modulus, elongation and uniform elongation.

The problem of testing multiple hypotheses at once is called the problem of multiple testing. We focused on comparing more than two means in one- way analysis of variance, also known as ANOVA. We dealt with the Tukey me- thod, the Hothorn-Bretz-Westfall method, the bootstrap-based methods and also the Bonferroni method and its modification by the Holm method, the last two methods being popular mainly for their simplicity. We focused in detail on the asymptotic behavior of these methods and then compared them using si- mulations in terms of compliance with the prescribed level and in terms of average strength. Bonferroni's method, which is conservative, is known to lose strength compared to other methods. However, its modification of Holm's method, which is also conservative, in some cases by its strength equates to other more complex methods. 1