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Integrated wireless-PON access network architecturesMilosavljevic, Milos January 2011 (has links)
Next generation access networks should be able to cultivate the ongoing evolution in services and applications. Advancements on that front are expected to exhibit the transformation of high definition television (HDTV) and 2D services into ultra-HDTV and individual interactive 3D services. Currently deployed passive optical networks (PONs) have been certified to be able to deliver high quality video and internet services while in parallel broadband wireless standards are increasing their spectral efficiency and subscriber utilisation. Exploiting the benefits of both by providing an integrated infrastructure benefiting from the wireless mobility and ease of scalability and escalating bandwidth of next generation PONs are expected to offer service providers the business models justifying the evolved services. In this direction, this thesis deals with the means of transparent routing of standard worldwide interoperability for microwave access (WiMAX) signal formats over legacy PONs to and from wireless end users based on radio over fibre (RoF). The concept of frequency division multiplexing (FDM) with RoF is used for efficient addressing of individual base stations, bandwidth on-demand provisioning across a cell/sector, simple remote radio heads and no interference with the baseband PON spectrum. Network performance evaluation, initially through simulation, has displayed, in the presence of optical non-linearites and multi-path wireless channels, standard error vector magnitudes (EVMs) at remote radio receivers and bit error rates (BERs) of 1E-4 for typical WiMAX rates bidirectionally. To provide enhanced scalability and dynamicity, a newly applied scheme based on extended wavelength band overlay over the splitter, wireless-enabled PONs has been progressively investigated. This allows for the routing of multiple FDM windows to different wavelengths resulting in significantly reduced optical and electrical component costs and no dispersion compensation over the fibre. This has been implemented through the application of a dense array wave guide grating (AWG) and tuneable filter in the optical line terminal (OLT) and optical network unit/base stations (ONU/BSs) respectively. Although with the use of a splitter the distribution point of the optical network remains largely the same, vertical cavity surface emitting laser (VCSEL) arrays provide colourless upstream transmission. In addition, an overlapping cell concept is developed and adopted for increased wireless spectral efficiency and resilience. Finally, an experimental test-bed using commercially available WiMAX transceivers was produced, which enabled repetition of the simulation outcomes and therefore confirmed the overall network performance.
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Over-Determination and Act-ConsequentialismJedenheim Edling, Magnus January 2017 (has links)
This dissertation is a discussion of the challenge that cases of over-determination pose to Act-Consequentialism. Although there are many realistic examples of such cases – for example, pollution, overfishing, or the election of an inappropriate politician – I consider structurally purer examples, one of which I call “Case One.” Suppose that you and I independently shoot and kill a third person called “Victim.” Our bullets arrive at the same time and each shot would have killed Victim by itself. Finally, Victim would not have been killed, if neither of us had pulled the trigger. According to the Standard Version of Act-Consequentialism, an action is wrong if and only if it has an alternative whose consequences would be intrinsically better. Case One challenges the Standard Version because there does not seem to be such an alternative to my action: Victim would have died by your shot if I had not shot him, and similar remarks apply to your action. The dissertation is structured as follows. After Chapter One, which briefly introduces the main issues of the dissertation, I turn to Chapter Two – “Preliminaries” – where I outline the Standard Version and highlight the main characteristics of over-determination cases. These cases are divided into cases of redundant difference making and cases of redundant causation. Cases of redundant causation are subdivided further into cases of causal over-determination and pre-emption. I make an important stipulation in this chapter. I say that our actions in Case One and similar cases are “redundant negative difference makers.” In Chapter Three – “Replies” – I consider whether the proponent of Act-Consequentialism might question the intuition that you and I, respectively, act wrongly in Case One. The proponent might accept that we have this intuition but explain it away, or she might deny that we have the intuition and instead point to something else that is wrong in this kind of case. For example, she could suggest that although neither you nor I act wrongly individually, we act wrongly together. I argue that these replies are problematic. For instance, explaining away this intuition might also force us to explain away intuitions that support the Standard Version. In Chapter Four – “Causal Consequences” – I discuss an alternative version of Act-Consequentialism that might seem to fare better. The Standard Version interprets the term “outcome of an action” as referring to the entire possible world that would obtain, if the action were performed. The version I have in mind, the “Causal Consequences Version of Act-Consequentialism,” understands “outcome of an action” as instead referring to the causal consequences of the action. It seems clear that you and I, respectively, cause the state of affairs that Victim dies in Case One. However, I show that the Causal Consequences Version has a number of unattractive implications. In Chapter Five – “the Non-Standard Version” – I suggest another alternative version of Act-Consequentialism. This version – the Non-Standard Version – implies that you and I act wrongly in Case One. Roughly, the Non-Standard Version says that an action is wrong if and only if it has an alternative whose consequences would be intrinsically better, or is a redundant negative difference maker. The Non-Standard Version is similar to a principle suggested by Derek Parfit. However, I shall argue that the Non-Standard Version is preferable to Parfit’s principle. In Chapter Six – “Further Cases” – I discuss a number of cases that challenge the Non-Standard Version. For example, what would the Non-Standard Version imply in a case very similar to Case One but where I would have killed another person, if I had not shot Victim? I argue that the Non-Standard Version handles this and other problematic cases, and that it is therefore a plausible alternative to the Standard Version.
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Assessment of the General Knowledge of Prescription and Over-The-Counter (OTC) Pain Medications in Older AdultsFlath, Ali, Hwang, Mandy, Nguyen, Yen January 2017 (has links)
Class of 2017 Abstract / Objectives: To assess older adults’ knowledge of prescription pain and over-the-counter (OTC) medications, to determine if age influences older adults’ choice of OTC pain agents, and to determine if education by a pharmacist about prescription and OTC pain medications impacts the score on a medication knowledge indicator.
Methods: This is a descriptive survey study. Participants received a recruitment email with a consent link in order to participate in the secure, online Qualtrics survey. The survey consists of 10 knowledge-based items on pain medications and 12 demographic items. The primary outcome of this study is the knowledge about pain medications of adult 75 years and older. Knowledge scores were analyzed using a Chi square test to compare the proportion of respondents in each age group who score 50% or more. The secondary outcome is the purchase pattern of OTC pain medications based on age. OTC purchasing data was analyzed using a nonparametric regression test. The tertiary outcome is the effect of pharmacist counseling on patients knowledge of prescription and OTC medications. The knowledge indicator scores were compared in patients who reported as either being educated by a pharmacist or not using a one-way ANOVA test.
Results: The questionnaire was completed by a total of 50 people, but three were excluded due to not meeting the age requirement of 50 years and older. Forty-seven participants were used in the analysis with mean age of 68.3 years (range 55 to 90) and 72% female. Of 44 participants who completed the entire survey those 75 years and older scored better on the knowledge indicator (71% scored ≥50%) compared with those 74 years and younger (54% scored ≥50%); however, no significant difference was found (p = 0.28). In addition, purchasing pattern based on percentage of both prescription and OTC medications between both groups appeared to be insignificantly different (p = 0.31 and 0.51 respectively). The mean number of OTC medications purchased equaled the mean number of OTC medications purchased for adults less than 75 years of age (Y = 1.2 vs. 1.2 medications per patient, p=0.51). Finally, all patients age 75 and older that reported being educated by a pharmacist scored 50% or greater on the knowledge indicator (100%) while 52% of participants 74 years and younger scored 50% or greater (p = 0.673).
Conclusions: Adults ages 75 years and older possess the same basic knowledge of pain medications when compared to adults age 50 to 74. In addition, adults age 75 years and older purchase over-the-counter (OTC) at the same rate as adults age 50 to 74. Finally, adults age 75 years and older benefit most from pharmacist consultation compared to adults age 50 to 74.
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Anxiety Sensitivity and Perceived Control Over Anxiety-Related Events: Evaluating the Singular and Interactive Effects in the Prediction of Anxious and Fearful Responding to Bodily SensationsGregor, Kristin 06 June 2008 (has links)
The current investigation examined the singular and interactive effects of anxiety sensitivity (AS) and perceived control over anxiety-related events in the prediction of panic symptoms using a biological challenge paradigm. Two hundred and twenty-nine participants (mage = 21.02, SD = 7.55, 124 females) were recruited from the greater Burlington, Vermont community. Results indicated that pre-challenge AS, but not perceived control over anxiety-related events, significantly predicted post-challenge panic attack symptoms, anxiety focused on bodily sensations, and interest in returning for another challenge (behavioral avoidance). There were no interactive effects between AS and perceived control over anxiety-related events. For the physiological measures, pre-challenge AS was predictive of change in skin conductance level (pre-post challenge), and pre-challenge perceived control over anxiety-related events was predictive of change in respiration rate (breathes per minute). No significant effects were evident for heart rate and there were no significant interactive effects between AS and perceived control over anxiety-related events for any of the physiological variables. Findings of the investigation are discussed in relation to the role of AS and perceived control over anxiety-related events in terms of vulnerability for panic psychopathology.
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Linearization techniques to suppress optical nonlinearityTabatabai, Farbod January 2009 (has links)
This thesis is shown the implementation of the linearization techniques such as feedforward and pre-distortion feedback linearization to suppress the optical components nonlinearities caused by the fibre and semiconductor optical amplifier (SOA). The simulation verified these two linearization techniques for single tone direct modulation, two tone indirect modulation and ultra wideband input to the optical fibre. These techniques uses the amplified spontaneously emission (ASE) noise reduction in two loops of SOA by a feed-forward and predistortion linearizer and is shown more than 6dB improvement. Also it investigates linearization for the SOA amplifier to cancel out the third order harmonics or inter-modulation distortion (IMD) or four waves mixing. In this project, more than 20 dB reductions is seen in the spectral re-growth caused by the SOA. Amplifier non-linearity becomes more severe with two strong input channels leading to inter-channel distortion which can completely mask a third adjacent channel. The simulations detailed above were performed utilizing optimum settings for the variable gain, phase and delay components in the error correction loop of the feed forward and Predistortion systems and hence represent the ideal situation of a perfect feed-forward and Predistortion system. Therefore it should be consider that complexity of circuit will increase due to amplitude, phase and delay mismatches in practical design. Also it has describe the compatibility of Software Defined Radio with Hybrid Fibre Radio with simulation model of wired optical networks to be used for future research investigation, based on the star and ring topologies for different modulation schemes, and providing the performance for these configurations.
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Operational benefit of implementing VoIP in a tactical environment / Operational benefit of implementing Voice Over Internet Protocol in a tactical environmentLewis, Rosemary 06 1900 (has links)
Approved for public release, distribution is unlimited / In this thesis, Voice over Internet Protocol (VoIP) technology will be explored and a recommendation of the operational benefit of VoIP will be provided. A network model will be used to demonstrate improvement of voice End-to-End delay by implementing quality of service (QoS) controls. An overview of VoIP requirements will be covered and recommended standards will be reviewed. A clear definition of a Battle Group will be presented and an overview of current analog RF voice technology will be explained. A comparison of RF voice technology and VoIP will modeled using OPNET Modeler 9.0. / Lieutenant, United States Navy
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Regulating the intelligence system and oversight in the Hungarian constitutional democracyBabos, Tibor 06 1900 (has links)
As Hungary made its transition to democracy, it had to overhaul its political, economic and defense system. The shift to a democratic form of government and free enterprise economy depends on a military that is firmly under civilian authority. Within the defense sector, the endurance of such a new democracy requires reforming its intelligence system. Hungary must choose the intelligence system that best serves its goals and needs. Despite the relatively strong success in implementing a democratic system, market economy and civilian control of the military since 1989, the transformation of its intelligence agencies is incomplete. The intelligence organizations holds fast to the old concept of an oversized, hyper bureaucratic intelligence system, and still lack appropriate, Western-type civil control and oversight. The system itself has been changing but not at the adequate speed and to some extent, it has kept the baggage of its past. Recent international terrorism also presents an opportunity to examine the Hungarian intelligence system and how it is structured, evaluating it for deficiencies and further develop what is working in the Hungarian security services. This analysis describes various other national intelligence organizations and examines intelligence oversight in the Hungarian constitutional democracy with recommendations for the possible guidelines for a new Hungarian intelligence system. / Hungarian Army author.
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Design of a practical voice over internet protocol network for the multi user enterpriseLoubser, Jacob Bester 06 1900 (has links)
Thesis (M. Tech. Engineering: Electrical--Vaal University of Technology. / This dissertation discusses the design and implementation of a voice over internet
protocol system for the multi-user enterprise. It is limited to small to medium enterprises of which the Vaal University of Technology is an example. Voice communications over existing Internet protocol networks are governed by standards, and to develop such a system it is necessary to have a thorough understanding of these standards. Two such standards namely the International Telecommunications Unions H.323 and the Internet Engineering Task Force's SIP were evaluated and compared to each other in terms of their complexity, extensibility and scalability as well as the services they offer. Based on these criteria it was decided to implement a SIP system.
A SIP network consists of application software that act as clients and servers, as well as hardware components such as a proxy and redirect and registrar or location servers that allow users of this network to call each other on the data network. Gateways enable users of the network to call regular public switched telephone network numbers. A test network was set up in the laboratory that contained all the hardware and software components. This was done to understand the installation and configuration options of the different
software components and to determine the suitability and interoperability of the software components. This network was then migrated to the network of the Vaal University of Technology which allowed selected users to test and use it. Bandwidth use is a major point of contention, and calculations and measurements showed that the codec being used during the voice call is the determining factor. This SIP system is being used on a daily basis and the users report excellent audio quality between soft phones and soft phones, soft phones and normal telephones and even cellular phones.
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Diseño de Red Power Over Ethernet con Categoría 6A para Aplicación en Data CenterLópez Córdova, Luis Alfredo January 2008 (has links)
La presente tesis describe el Proyecto de Diseño de una Red Over Ethernet sobre una red física DE 10 Gigabit Ethernet utilizando categoría 6A, demostrando la convergencia de estas dos tecnologías logrando el mayor rendimiento y cumpliendo con todas las normas internacionales y nacionales aplicados en un Data Center.
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Studies on gene ARR expressionGianniosis, Mary 19 May 2008 (has links)
ABSTRACT
Rifampicin is a major chemotherapeutic agent used against mycobacterial and
nocardial infections. High level resistance is primarily due to mutational
alterations in the rpoB gene encoding the β subunit of RNA polymerase. When
challenged, these bacteria may inactivate rifampicin by one of four mechanisms:
decomposition, ADP-ribosylation, glucosylation and phosphorylation. ADPribosylation
occurs in many mycobacterial pathogens but nothing is known about
the properties of the enzyme responsible. Consequently mutational analysis may
be used to explore structure-function relationships in this protein.
Three mutants with changes in the open reading frame were selected and studied.
The altered arr gene in pMG1 was obtained by in vivo selection whilst in pMG2
and pMG4 by in vitro mutagenesis. The mutated arr gene in pMG1 and pMG2
conferred resistance to 50 μg/ml of rifampicin while in pMG4 to 200 μg/ml. This
suggested that alterations near the N-terminus resulted in lowered activity because
of closer proximity to the active site. This is the first successful report of induced
arr gene expression. This over-expression of the Arr ADP-ribosyltransferase and
its mutants assisted in their later purification by metal affinity chromatography.
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