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LINKING SERVICE ENCOUNTERS TO FINANCIAL PERFORMANCE: AN EXTENDED APPROACH TO VALUATIONChilders, Carla Yvonne 01 January 2009 (has links)
Managers and researchers have become increasingly interested in linking marketing activities to firm financial performance. That is, they desire to make marketing more financially accountable. One approach to achieving this goal has been to “valuate” customers to determine their degrees of profitability over the lifetime of their relationships with firms. However, traditional customer valuation techniques are largely based on quantitative factors and do not account for softer measures such as a customer’s behavior and performance both during and after service encounters.
Additionally, while customer profitability is commonly valuated, employees are not generally assessed in this manner in profit linkage frameworks. This indicates that employee factors have not been deemed to have an equivalent, direct impact on the bottom line. Instead, if included at all, employee factors have mainly been positioned as antecedents to customer factors in past linkage models. Because both customers and employees play essential roles in determining the success of service encounters, both customer and employee factors should be fully considered before profitability is determined.
In this dissertation, an innovative theoretical model is presented in which past profit linkage research is extended to include nonfinancial considerations. This research merges traditional financial valuation methods with nonfinancial metrics to assess organizational performance. Furthermore, a conceptually parallel framework is developed in which both employee and customer factors are hypothesized as links through which service encounter dynamics can be connected to firm financial performance. This research examines the linkages between service interactions, customer and employee outcomes, and overall financial performance.
Within the contexts of two studies, the overall structural model is dissected into comparable performance models and examined within the retail banking and computer services industries. The overall empirical findings provide some evidence of a positive flow of interconnected relationships between service encounter dynamics and firm financial performance. Accordingly, this research presents some indication of the importance of service encounters as antecedents to outcome behaviors that have critical financial consequences.
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Using Existing Infrastructure as Support for Wireless Sensor NetworksNeander, Jonas January 2006 (has links)
<p>Denna avhandling handlar om hur befintliga datorinfrastrukturer i t.ex. sjukhus och industrier kan avlasta sensornätverk med energikrävande uppgifter. Vi har forskat på olika aspekter som gör det möjligt att förlänga livslängden på dessa sensornätverk. Avhandlingen presenterar en ny plattform för sensornätverk tillsammans med inledande simuleringar som påvisar att vår plattform ökar livslängden på dessa typer av nätverk.</p><p>Generella sensornätverk är uppbyggda av tätt grupperade, trådlösa, batteridrivna datorer som kan vara så små som en kubikmillimeter. Datorerna kallas för sensorer eller sensornoder eftersom de har en eller flera inbyggda sensorer som känner av sin omgivning. En sensor har till uppgift att samla information från sin omgivning, t.ex. temperatur, fuktighet, vibrationer, hjärtslag eller bilder. Sensorerna skickar sedan informationen till en insamlingsstation någonstans i nätverket.</p><p>I de typer av tillämpningar vi tittar på är det viktigt att minimera energiförbrukningen, så att man maximerar livslängden på sensornätverket. Avhandlingen presenterar en lösning där befintlig datorinfrastruktur fungerar som hjälpdatorer/avlastare till ett sensornätverk. Hjälpdatorerna, eller basstationerna som vi kallar dem i avhandlingen, hanterar energikrävande uppgifter som t.ex. vilken sensor som ska kommunicera med vem samt vid vilken tidpunkt etc. Då kan sensorerna i nätverket fokusera på att utföra sina egna uppgifter tills dess att basstationen säger att uppgifterna ändrats.</p><p>Simuleringar visar att vår plattform kan skicka upp till 97 % mera information till basstationen än en jämförbar plattform med samma energimängd. 88 % av våra sensorer är fortfarande vid liv när den andra plattformens sensorer förbrukat all sin energi.</p><p>Ett exempel på hur dessa typer av nätverk kan användas är att övervaka patienters hälsa och kondition i sjukhus eller sjukhem. Patienter behöver inte ha en fast sängplats där en viss typ av medicinskt övervakningsinstrument finns tillgänglig utan kan placeras där det finns en ledig sängplats. Via trådlös kommunikation skickar sensorerna sedan hälsoinformation som t.ex. hjärtfrekvens och blodtryck till en basstation som i sin tur skickar vidare till ett centralt övervakningsinstrument någonstans på sjukhuset. Övervakningsinstrumentet behandlar informationen och larmar personal med rätt kompetens vid behov. Larmet kan skickas till en mobiltelefon eller en liten handdator som personalen alltid bär med sig. Med larmet skickas även information om var patienten befinner sig och all nödvändig data för att personalen snabbt ska kunna ställa en första diagnos. På detta sätt kan man spara in på antalet specialbyggda sängplatser och slippa dyrbara installationer av medicintekniska utrustningar knutna till en sängplats.</p> / <p>Recent advancements in electronic design, such as low-power circuits, energy efficient wireless communication, and improved energy supply, has enabled the vision of wireless sensor networks to become a reality. Wireless sensor networks typically consist of hundreds up to thousands of collaborating low-cost, battery-driven and wireless sensor nodes with scarce resources. The wireless sensor nodes are typical small physical entities, and usually small as a matchbox but can in extreme cases be no larger than a cubic millimeter.</p><p>In this thesis we present an architecture called AROS that uses existing infrastructure to aid in the management of wireless sensor networks. As an example, the existing infrastructure could be situated in hospitals or industrial buildings. The existing infrastructure can aid in prolonging the lifetime of the wireless sensor network by having "unlimited'' energy, long range radio capacity, and high-speed computers. We enable prolonged lifetime by centralizing some of the energy consuming administrative functionality of wireless sensor networks.</p><p>We show, by simulations, that the AROS architecture is able to prolong the lifetime of the sensor nodes. AROS is compared to a well known cluster based architecture, LEACH. The comparisons show that AROS with static configuration performs at least as well as LEACH in small wireless sensor networks in the size 100x100m, and up to 97 % better in long distance wireless sensor networks in the size of 400x400m. We show that AROS still has got 88 % of its sensor nodes alive when LEACHs' network demises.</p><p>In our simulations we have also studied how dynamic network clustering in AROS, using a TDMA scheduler and non-mobile wireless sensor nodes, affects the amount of data received by a base station. We show that AROS is better than LEACH-C in collecting data to the base station with the same total amount of energy for long distance networks and that AROS performs as well or better than LEACH-C in small wireless sensor networks.</p>
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Phase-Space Properties of Two-Dimensional Elastic Phononic Crystals and Anharmonic Effects in Nano-Phononic CrystalsSwinteck, Nichlas Z. January 2012 (has links)
This dissertation contains research directed at investigating the behavior and properties of a class of composite materials known as phononic crystals. Two categories of phononic crystals are explicitly investigated: (I) elastic phononic crystals and (II) nano-scale phononic crystals. For elastic phononic crystals, attention is directed at two-dimensional structures. Two specific structures are evaluated (1) a two-dimensional configuration consisting of a square array of cylindrical Polyvinylchloride inclusions in air and (2) a two-dimensional configuration consisting of a square array of steel cylindrical inclusions in epoxy. For the first configuration, a theoretical model is developed to ascertain the necessary band structure and equi-frequency contour features for the realization of phase control between propagating acoustic waves. In contrasting this phononic crystal with a reference system, it is shown that phononic crystals with equifrequency contours showing non-collinear wave and group velocity vectors are ideal systems for controlling the phase between propagating acoustic waves. For the second configuration, it is demonstrated that multiple functions can be realized of a solid/solid phononic crystal. The epoxy/steel phononic crystal is shown to behave as (1) an acoustic wave collimator, (2) a defect-less wave guide, (3) a directional source for elastic waves, (4) an acoustic beam splitter, (5) a phase-control device and (6) a k-space multiplexer. To transition between macro-scale systems (elastic phononic crystals) and nano-scale systems (nano-phononic crystals), a toy model of a one-dimensional chain of masses connected with non-linear, anharmonic springs is utilized. The implementation of this model introduces critical ideas unique to nano-scale systems, particularly the concept of phonon mode lifetime. The nano-scale phononic crystal of interest is a graphene sheet with periodically spaced holes in a triangular array. It is found through equilibrium molecular dynamics simulation techniques, that phonon-boundary collision effects and coherent phononic effects (band-folding) are two competing scattering mechanisms responsible for the reduction of acoustic and optical phonon lifetimes. Conclusions drawn about the lifetime of thermal phonons in phononic crystal patterned graphene are linked with the anharmonic, one-dimensional crystal model.
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Magnetic rotation in the A1̃10 regionJenkins, David Gareth January 1999 (has links)
No description available.
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Lifetime measurement of '1'5'8Er using the recoil distance methodShepherd, Sarah Louise January 1999 (has links)
No description available.
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FRET analysis of splicing factors involved in exon and intron definition in living cellsEllis, Jonathan January 2008 (has links)
I have analyzed the interactions between SR proteins and splicing components that are bound at the 5’ or 3’ splice site using fluorescence resonance energy transfer (FRET) microscopy. The SR proteins interact with the U1 snRNP-associated 70 kDa protein (U170K) at the 5’splice site and with the small subunit of the U2 snRNP auxiliary factor (U2AF35) at the 3’ splice site. These interactions have been extensively characterized biochemically in the past, and are proposed to play roles in both intron and exon definition. We employed FRET acceptor photobleaching and fluorescence lifetime imaging microscopy (FLIM) to identify and spatially localise sites of direct interactions of SF2/ASF, and other SR proteins, with U2AF35 and U1-70K in live cell nuclei. These interactions were shown to occur more strongly in interchromatin granule clusters (IGCs). They also occur in the presence of the RNA polymerase II inhibitor, DRB, demonstrating that they are not exclusively co-transcriptional. FLIM data have also revealed a novel interaction between HCC1, a factor highly related to the large subunit of the U2AF splicing factor, with both subunits of U2AF that occur in discrete domains within the nucleoplasm but not within IGCs. These data demonstrate that the interactions defining intron and exon definition do occur in living cells in a transcription-independent manner.
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Multi-parameter quantitative mapping of microfluidic devicesBennet, Mathieu A. January 2011 (has links)
Fluorescence lifetime imaging microscopy (FLIM) is a powerful technique to non-invasively map the physical and chemical environment within microfluidic devices. In this work FLIM has been used in conjunction with a variety of other techniques to provide a greater insight into flow behaviour and fluid properties at the microscale. The pH-sensitive fluorescent dyes, fluorescein and C-SNARF 1, have been used to generate pH maps of microfluidic devices with a time-gated camera and a time-and-space-correlated single photon counting (TSCSPC) detector, respectively. Using time-gated detection and fluorescein, the fluorescence lifetime images allow for direct reading of the pH. The relative contribution to fluorescence of the acid and basic forms of C-SNARF 1 was spatially resolved on the basis of pre-exponential factors, giving quantitative mapping of the pH in the microfluidic device. Three dimensional maps of solvent composition have been generated using 2-photon excitation FLIM (2PE-FLIM) in order to observe the importance of gravitational effects in microfluidic devices. Two fluidic systems have been studied: glycerol concentration in the microfluidic device was measured using Kiton red; water concentration in a methanolic solution was measured using ANS. The density mismatch between two solutions of different composition induced a rotation of the interface between two streams travelling side by side in a microchannel. The experiment has provided evidence of non-negligible gravitational effects in microflows. 2PE-FLIM has superior capability than methods used previously to assess similar phenomena. FLIM and micro-particle imaging velocimetry (μ-PIV) have been implemented on a custom-built open frame microscope and used simultaneously for multimodal mapping of fluid properties and flow characteristics. It has been shown that viscosity mismatch between two streams induces a non-constant advective transport across the channel and results in a flow profile that deviates from the usual Poiseuille profile, characteristic of pressure driven flow in microfluidic devices.
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Desarrollo de un método de valoración de clientes en una empresa del sector automotrizOsses Godoy, Alex Alfredo January 2015 (has links)
Ingeniero Civil Industrial / En el mundo competitivo de hoy, el conocimiento de los clientes puede transformarse en una ventaja para las empresas. Lo anterior se debe a que cada individuo es diferente y pueden presentar distintos comportamientos, existiendo algunos que son más rentables que otros, por lo que detectarlos y enfocarse en los clientes correctos representa potenciales ganancias a futuro. En base a lo anterior, en este proyecto se propone el desarrollo de una metodología de valoración de clientes de una importante empresa del sector automotriz, específicamente en el subsector de camiones medianos de una de las marcas que representa.
El método propuesto tiene como objetivo apoyar a las áreas comerciales a focalizar la retención y fidelización de los clientes más valiosos mediante la generación de recomendaciones de distintos tipos de acciones de marketing a enfocar en diferentes grupos de clientes para así mejorar su gestión. Lo anterior implica la estimación del valor futuro de los clientes, para lo cual se utiliza la métrica de CLV (Customer Lifetime Value). Para estimarla, se proponen 2 modelos ampliamente utilizados en distintas industrias para la estimación del número de transacciones: Uno probabilístico (BG-NBD) y uno econométrico (Logit-Poisson-Markov). Por otro lado, para la estimación de los montos se utiliza el modelo probabilístico Gamma-Gamma.
Las métricas de ajuste utilizadas para validar los modelos indican que el modelo econométrico es el que presenta el mejor desempeño para la estimación del número de transacciones, el cual se utiliza en conjunto con el modelo probabilístico que estima los montos para así proyectar el valor futuro de los clientes.
Utilizando el valor histórico generado por los clientes y su valor proyectado para el año actual y para un plazo de 5 años (utilizando el modelo desarrollado) se propone una agrupación de clientes en base a estas 3 variables. A partir de la agrupación propuesta se realizan recomendaciones de acciones de marketing a los distintos grupos generados, logrando así apoyar a las áreas comerciales a la focalización de los esfuerzos a realizar con la cartera de clientes.
Los clientes más valiosos para el plazo de 5 años utilizados resultan ser los clientes tipo empresa que se desempeñan en el rubro "R2" y que además de tener vehículos medianos poseen vehículos livianos y/o pesados dentro de la misma marca. Estos representan un valor promedio de $ 101.522.185 en el plazo señalado.
El modelo de valoración y su utilización propuesta significan el punto de partida para la empresa en la búsqueda de un enfoque relacional, que busca comprender, mejorar y aumentar las relaciones que posee actualmente con su cartera de clientes.
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Making Nuclear Magnetic Hyperpolarization Practical through Storage in Disconnected EigenstatesClaytor, Kevin E. January 2015 (has links)
<p>There are two fundamental limitations in magnetic resonance: the poor signal amplitude and the short duration before the system return to equilibrium. Hyperpolarization methods solve the problem of signal amplitude, however, the duration of the hyperpolarized signal is still limited by the spin-lattice relaxation time, T1. Disconnected eigenstates provide a mechanism by which hyperpolarization can be stored for several times T1. This thesis contributes to the knowledge of these states in four important ways. First, the decay of hyperpolarized magnetization of gas is simulated in lung tissue with a contrast agent, yielding insights about the optimal field strength for imaging. Second, I show that it is possible to rapidly discover and characterize disconnected eigenstates by showing that they can be measured without synthesizing the isotopically labeled compound. Third, I extend the spin systems that can support disconnected eigenstates by expanding the theory to include spin-1 nuclei. Finally, I show that disconnected states with long lifetimes can be populated in conjunction with hyperpolarization techniques to simultaneously yield large signal amplitudes for long durations. </p><p>Applications of hyperpolarized spin order are likely to be in complex geophysical or biological structures. Understanding the effect of the inhomogeneous fields created when such structures are placed in a magnetic field on hyperpolarized spin order is a necessity to characterize the experimental signal. An example case of hyperpolarized 3He and 129Xe diffusing through lung tissue is examined. In particular a Monte Carlo simulation tool, combined with a magnetic field map of the inhomogeneous field created by mouse lung tissue, is used to determine the dephasing rate of hyperpolarized 3He and 129Xe in the presence of SuperParamagnetic Iron Oxide Nanoparticles (SPION). Contributions to the dephasing rate include the inhomogeneous field, the SPION magnetic field, and dephasing caused by collisions with the confining geometry. The sensitivity of either gas to SPION increases with increasing SPION concentration and decreasing field strength.</p><p>There are some general rules about what makes for a disconnected eigenstate (or singlet state) with a long lifetime. However, no systematic experimental study has been undertaken due to the cost and time-constraints of synthesizing the labeled species for study. I show that synthesis is not a barrier for characterizing the long-lived states. Instead the lifetimes may be determined by using the naturally occurring doubly-labeled isotopomer. I verified this method with two compounds, diphenyl acetylene (DPA) and diethyl oxylate (DEO). The former was determined to have a singlet lifetime TS = 251.40 ±3.16 s from the synthesized species, while the naturally occurring isotopomer yielded a lifetime TS = 202 ±55.30 s, both substantially longer than the spin-lattice relaxation time, T1 = 1.63 ±0.01s. In DEO, the lifetime from the disconnected eigenstate was determined to be TS = 14.62 ±0.76 s (synthesized), TS = 19.32 ±3.16 s (naturally occurring). This method is applied to a range of compounds ranging from simple four-spin systems, such as diacetylene (TS = 48.80 ±22.74 s, T1 = 18.66 ±1.16 s) to eight spin systems in dimethylmaleic anhydride (TS = 27.25 ±3.39 s, T1 = 9.38 ±0.43 s). Additionally, a family of compounds including naphthalene (TS = 4.37 ±0.34 s, T1 = 11.33 ±4.89 s), biphenyl (TS = 3.09 ±0.66 s, T1 = 4.69 ±0.10 s), and DPA show that the rotation of the phenyl rings and intermolecular dipole-dipole relaxation can be critical to the relaxation dynamics.</p><p>One particular method of accessing the disconnected eigenstate involves coupling a chemically equivalent spin-1/2 pair asymmetrically to an auxiliary spin-1/2 pair. I demonstrate that the disconnected state may still be accessed when the auxiliary nuclei are spin-1. This has two distinct advantages. When the auxiliary nuclei change from proton to deuterium, the couplings are reduced by a factor of ~6.5 which prevents the disconnected state from relaxing as rapidly back to equilibrium. This is demonstrated in diacetylene-d2 and DPA-d10, where the singlet lifetime was extended by a factor of ~1.7 via deuteration (TS,1H = 49 ±23 s, TS,2H = 83 ±30 s for diacetylene and TS,1H = 274 ±6.1 s, TS,2H = 479 ±83 s for DPA). Additionally, by reducing the coupling strength, deuteration allows additional structural moieties to be explored, such as RDC=CDR. One such structure is explored in trans-ethylene-d2, where the singlet character of the protons can be accessed by the reduced coupling to the deuterium. Additionally, this allows for a relatively strong deuterium-deuterium scalar coupling, requiring modification to the theory. This is carried out analytically, and implications for the relaxation properties are performed using a spin-dynamics numerical simulation. The lifetime of the disconnected state was determined to be TS = 30.2 ±12.3 s, compared to the T1 = 1.1 ±0.2 s at high concentration (270 mM), and increasing to TS = 117. ±9.80 s at low concentration (52 mM). The variation in long lifetime is attributed to intermolecular dipole-dipole relaxation.</p><p>Ultimately, the gains in lifetime from using disconnected eigenstates provide a means to the practical implementation of hyperpolarization in a wider range of experiments. A recent hyperpolarization method, Signal Amplification By Reversible Exchange in Shield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH) is shown to directly hyperpolarize long lived spin order in a diazirine containing molecule. Diazirine rings are three member N=N-C groups that can replace a methylene group and serve as a versatile MR and optical molecular tag. Hyperpolarization is accomplished by bubbling parahydrogen through a solution containing the diazirine and an iridium catalyst. Due to the chemical inequivalence of the 15N of the diazirine, hyperpolarization of longitudinal magnetization and singlet character could be observed by transfer to the high field spectrometer. Signal enhancements of over 14,000 were observed. The magnetic field strength required for buildup of magnetization and singlet character was derived and is in agreement with the experiment. The magnetization lifetime was observed to be T1 = 5.75 ±0.18 minutes and independent of field strength, while the lifetime of the singlet character was observed to be as long as TS = 30.1 ±13.4 minutes at low field (3 Gauss).</p><p>The combination of these experiments – understanding lifetimes in inhomogeneous magnetic fields that will be encountered in experiment, identification of disconnected eigenstates with long lifetimes via the naturally occurring isotopomer and extending these lifetimes even further with deuteration, and finally, the direct generation of long-lived hyperpolarized spin order – allows a measurement that required hyperpolarized spin order for the enhanced signal amplitude, to be carried out.</p> / Dissertation
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Order-statistics-based inferences for censored lifetime data and financial risk analysisSheng, Zhuo January 2013 (has links)
This thesis focuses on applying order-statistics-based inferences on lifetime analysis and financial risk measurement. The first problem is raised from fitting the Weibull distribution to progressively censored and accelerated life-test data. A new orderstatistics- based inference is proposed for both parameter and con dence interval estimation. The second problem can be summarised as adopting the inference used in the first problem for fitting the generalised Pareto distribution, especially when sample size is small. With some modifications, the proposed inference is compared with classical methods and several relatively new methods emerged from recent literature. The third problem studies a distribution free approach for forecasting financial volatility, which is essentially the standard deviation of financial returns. Classical models of this approach use the interval between two symmetric extreme quantiles of the return distribution as a proxy of volatility. Two new models are proposed, which use intervals of expected shortfalls and expectiles, instead of interval of quantiles. Different models are compared with empirical stock indices data. Finally, attentions are drawn towards the heteroskedasticity quantile regression. The proposed joint modelling approach, which makes use of the parametric link between the quantile regression and the asymmetric Laplace distribution, can provide estimations of the regression quantile and of the log linear heteroskedastic scale simultaneously. Furthermore, the use of the expectation of the check function as a measure of quantile deviation is discussed.
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