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A research of customer lifetime value based on IT-enable service in travel blogsShiue, Chiou-yen 21 July 2008 (has links)
An expected boom of local travel market is rising, as well as the stronger requirement of diversified travel information/resource services, when the government policy of the strait is improving and the constraints for the tourists from Mainland China will be official released. Some of the travel information/resources and the related behavior of end user on internet have been dramatically influenced by Web 2.0 concept, the service encounter on web has been substituted by the voluntary participation/sharing gradually. Hence, this research will study and measure the relationships and influences of travel information among information transmission and interaction of service, customer satisfaction,trust, and customer lifetime value which based on Web 2.0 technology for local commercial travel blogs.
An online questionnaire survey has been applied for the users of local commercial travel blogs, and 635 effective samples have been received. The SEM(structural equation modeling) is adopted for analyze the collected datums with package software SPSS and AMOS for testing the path relationship of variables, parameter estimation and goodness of fit for our model.
This research identified that direct relationship between technology infusion in service encounter and perceived service quality but customer satisfaction, nevertheless, the customer satisfaction by perceived service quality can not be affected directly by technology infusion in service encounter. Further, the perceived service quality related to customer satisfaction so as to trust. And, the technology infusion in service encounter can affect customer lifetime value by perceived service quality, customer satisfaction and trust indirectly.
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Biophysical Characterization of the Dynamic Regulation of Chromatin Structure and Rheology in Human Cell NucleiSpagnol, Stephen 01 May 2015 (has links)
Out of the growing body of evidence demonstrating the role of higher-order chromatin organization within the nucleus in regulating the functions of the linear sequence of DNA emerges the genome as a physical entity. DNA packs into hierarchical levels of chromatin condensation, which then tailor accessibility to the linear sequence for nuclear processes while also serving as a central feature of nuclear organization. Further, varying condensation state alters the physical properties of the chromatin fiber. These may then exert or facilitate forces aiding in the spatial organization within the nucleus. Yet, this complex concept of nuclear structure even neglects the dynamic aspects of the genome continuously fluctuating and undergoing structural remodeling within the nucleus. Thus, while chromatin position within the nucleus is critical for biological functions including transcription, we must reconcile a particular position of a gene locus with the dynamic and physical nature of chromatin. Here we characterize the physical aspects of the genome associated with its dynamic properties that aid in regulation. We focus on developing techniques that measure the evolution of physical properties associated with nuclear processes. We leverage these techniques, capable of quantifying and spatially resolving its structural state within the nucleus and elucidating the underlying physics of its dynamics, to illuminate physical features associated with cellular processes. Specifically, we investigate the nuclear structural changes associated with growth factor stimulation on primary human cells known to impact large scale gene expression pathways. We also demonstrate dysfunction associated with these physical mechanisms accompany disease pathologies. Thus, we unify the biological understanding of cellular processes within the context of physical features of genome structure, organization and dynamics that are critical to human health and disease.
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Development of new methods in fluorescence microscopyLin, Chao-Chen 18 May 2015 (has links)
No description available.
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The Drivers of a Successful Corporate Sponsorship and the Quantified Financial Impact: Applying the Attitudinal Triad of Cognition, Affect, and Conation and Customer Lifetime Value to Corporate SponsorshipsNickell, David 18 December 2010 (has links)
While the volume of research on corporate event sponsorships as a marketing tool has increased markedly over the past decade, the results have done little to help marketers to justify sponsorship spending. Not only do marketers have little knowledge of a sponsored event’s financial return, they also struggle to demonstrate any impact on consumer behavior at all.
Using multi-wave survey data, we quantified the financial impact of a sponsorship. We predicted the number of new buyers based upon changed brand attitudes, consistent with a hierarchy of effects model. We then established the financial return on the sponsorship spending by estimating the customer lifetime value (CLV) of these new buyers.
We collected the data around a major college football bowl game. Six phases of data collection were used to determine purchasing behavior and brand attitudes of attendees before and after the sponsored event, in comparison to television viewers of the event and the general public. We applied Lavidge and Elrick’s (1961) attitudinal constructs as the independent variables in a logistic regression to predict future purchase. The final data collection was used to validate the model’s prediction.
The findings show that the model accurately predicted the number of new customers after one buying cycle for the sponsor’s products. We also quantified the positive impact of the sponsorship on the CLV of existing customers within the same time frame.
The managerial implications of this study are significant. Sponsorships are highly risky, with fixed outlays up front, and unclear benefits to be realized in the future. We provide a methodology that not only allows sponsors to measure the effectiveness of the sponsorship, but to determine the return on their sponsorship investment. We have taken consumer behavior theory from marketing communications research and combined it with CLV tools, thus allowing marketers to determine the number of new customers that a sponsorship generates, as well as how it influences the buying patterns that drive customer lifetime value.
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Copula Models for Multi-type Life History ProcessesDiao, Liqun January 2013 (has links)
This thesis considers statistical issues in the analysis of data in the studies of chronic diseases which involve modeling dependencies between life history processes using copula functions.
Many disease processes feature recurrent events which
represent events arising from an underlying chronic condition; these are often modeled as point processes.
In addition, however, there often exists a random variable which is realized upon the occurrence of each event, which is called a mark of the point process. When considered together, such processes are called marked point processes. A novel copula model for the marked point process is described here which uses copula functions to govern the association between marks and event times. Specifically, a copula function is used to link each mark with the next event time following the realization of that mark to reflect the pattern in the data wherein larger marks are often followed by longer time to the next event.
The extent of organ damage in an individual can often be characterized by ordered states, and interest frequently lies in modeling the rates at which individuals progress through these states. Risk factors can be studied and the effect of therapeutic interventions can be assessed based on relevant multistate models. When chronic diseases affect multiple organ systems, joint modeling of progression in several organ systems is also important.
In contrast to common intensity-based or frailty-based approaches to modelling, this thesis considers a copula-based framework for modeling and analysis. Through decomposition of the density and by use of conditional independence assumptions, an appealing joint model is obtained by assuming that the joint survival function of absorption transition times is governed by a multivariate copula function. Different approaches to estimation and inference are discussed and compared including composite likelihood and two-stage estimation methods. Special attention is paid to the case of interval-censored data arising from intermittent assessment.
Attention is also directed to use of copula models for more general scenarios with a focus on semiparametric two-stage estimation procedures. In this approach nonparametric or semiparametric estimates of the marginal survivor functions are obtained in the first stage and estimates of the association parameters are obtained in the second stage. Bivariate failure time models are considered for data under right-censoring and current status observation schemes, and right-censored multistate models. A new expression for the asymptotic variance of the second-stage estimator for the association parameter along with a way of estimating this for finite samples are presented under these models and observation schemes.
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GRID-BASED DEPLOYMENT FOR WIRELESS SENSOR NETWORKS IN OUTDOOR ENVIRONMENT MONITORING APPLICATIONSAL-TURJMAN, FADI 02 May 2011 (has links)
Wireless Sensor Networks (WSNs) overcome the difficulties of other monitoring systems, as they require no human attendance on site, provide real-time interaction with events, and maintain cost and power efficient operations. However, further efficiencies are required especially in the case of Outdoor Environment Monitoring (OEM) applications due to their harsh operational conditions, huge targeted areas, limited energy budget, and required Three-Dimensional (3D) setups. A fundamental issue in defeating these practical challenges is the deployment planning of the WSNs. The deployment plan is a key factor of many intrinsic properties of OEM networks, summarized in connectivity, lifetime, fault-tolerance, and cost-effectiveness. In this thesis, we investigate the problem of WSNs deployments that address these properties in order to overcome the unique challenges and circumstances in OEM applications.
A natural solution to this problem is to have multiple relay nodes that reserve more energy for sensing, and provide vast coverage area. Furthermore, assuming a subset of these relay nodes are mobile can contribute in repairing the network connectivity problems and recovering faulty nodes, in addition to granting balanced load distributions, and hence prolonging the network lifetime. We investigate this promising research direction by proposing a 3D grid-based deployment planning for heterogeneous WSNs in which Sensor Nodes (SNs) and Relay Nodes (RNs) are efficiently deployed on grid vertices. Towards this efficiency, we analyze and characterize the grid connectivity property in the 3D space. Afterward, we design optimization schemes for the placement of SNs and RNs on the 3D grid models. Based on theoretical analysis and extensive simulations, the proposed schemes show a significant enhancement in terms of network connectivity and lifetime in OEM applications. / Thesis (Ph.D, Computing) -- Queen's University, 2011-05-02 10:29:01.785
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Studies in Saving under UncertaintySkult, Eva January 2010 (has links)
This thesis consists of three essays. In Precautionary Saving under Correlated Risk, I show that the sign of the correlation between the random variables might determine whether saving increases or decreases when risk is introduced. Precautionary saving is thus not confirmed. In the second part of this chapter, the consumer must also allocate her saving between an insurance and an interest-bearing asset. It is shown that switching the sign of correlation changes the optimal insurance ratio and probably also optimal saving. Saving and Portfolio Choice by Mutually Altruistic Consumers treats the effects of mutual altruism between two individuals. Compared to the Utilitarian social optimum there is, on the one hand, a tendency to higher saving and lower risk share resulting from the higher uncertainty of future income in the Nash equilibrium. On the other hand, there is a tendency to lower saving and higher risk share arising from the possibility of a free ride on the generosity of others, named "Samaritan's Dilemma". Analytically, it was not possible to determine the size or the direction of divergences in the choice variables. Numerical examples show that the effect of the Samaritan's Dilemma outweighs the effect of the greater uncertainty of future income in the Nash equilibrium. However, the divergence in saving between the two solutions is rather small. In the literature, uncertain lifetime has been used to explain both unexpectedly low and unexpectedly high saving by the elderly. In The Effect of Uncertain Lifetime on the Saving of the Elderly, risk is introduced into the remaining lifetime and the consequences of a background risk are investigated. Introducing uncertain lifetime into the certainty model results in a slower decumulation of wealth from the date of retirement. On the contrary, introducing uncertain lifetime into a model with uncertain investment income results in a swifter decumulation and an earlier depletion of wealth.
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Positronium scattering by the noble gasesBlackwood, Jennifer Elizabeth January 2000 (has links)
No description available.
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Life of Photosynthetic Complexes in the Cyanobacterium Synechocystis sp. PCC 6803January 2011 (has links)
abstract: The cyanobacterium Synechocystis sp. PCC 6803 performs oxygenic photosynthesis. Light energy conversion in photosynthesis takes place in photosystem I (PSI) and photosystem II (PSII) that contain chlorophyll, which absorbs light energy that is utilized as a driving force for photosynthesis. However, excess light energy may lead to formation of reactive oxygen species that cause damage to photosynthetic complexes, which subsequently need repair or replacement. To gain insight in the degradation/biogenesis dynamics of the photosystems, the lifetimes of photosynthetic proteins and chlorophyll were determined by a combined stable-isotope (15N) and mass spectrometry method. The lifetimes of PSII and PSI proteins ranged from 1-33 and 30-75 hours, respectively. Interestingly, chlorophyll had longer lifetimes than the chlorophyll-binding proteins in these photosystems. Therefore, photosynthetic proteins turn over and are replaced independently from each other, and chlorophyll is recycled from the damaged chlorophyll-binding proteins. In Synechocystis, there are five small Cab-like proteins (SCPs: ScpA-E) that share chlorophyll a/b-binding motifs with LHC proteins in plants. SCPs appear to transiently bind chlorophyll and to regulate chlorophyll biosynthesis. In this study, the association of ScpB, ScpC, and ScpD with damaged and repaired PSII was demonstrated. Moreover, in a mutant lacking SCPs, most PSII protein lifetimes were unaffected but the lifetime of chlorophyll was decreased, and one of the nascent PSII complexes was missing. SCPs appear to bind PSII chlorophyll while PSII is repaired, and SCPs stabilize nascent PSII complexes. Furthermore, aminolevulinic acid biosynthesis, an early step of chlorophyll biosynthesis, was impaired in the absence of SCPs, so that the amount of chlorophyll in the cells was reduced. Finally, a deletion mutation was introduced into the sll1906 gene, encoding a member of the putative bacteriochlorophyll delivery (BCD) protein family. The Sll1906 sequence contains possible chlorophyll-binding sites, and its homolog in purple bacteria functions in proper assembly of light-harvesting complexes. However, the sll1906 deletion did not affect chlorophyll degradation/biosynthesis and photosystem assembly. Other (parallel) pathways may exist that may fully compensate for the lack of Sll1906. This study has highlighted the dynamics of photosynthetic complexes in their biogenesis and turnover and the coordination between synthesis of chlorophyll and photosynthetic proteins. / Dissertation/Thesis / Ph.D. Plant Biology 2011
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Do the Lifetime Prevalence and Prognosis of Schizophrenia Differ Among World Regions?Smith, Cheryl Lynn 01 January 2018 (has links)
Much cross-cultural research has been done on the topic of schizophrenia, but few studies thus far have focused on lifetime prevalence and prognosis together, grouped by world region. Additionally, there has been severe bias in which countries and regions have been studied both historically and currently. Any study that had statistics on lifetime prevalence per 1000 people and/or DALYs, from a specified country or region, was included in this thesis. Results showed that lifetime prevalence of schizophrenia does not differ among WHO regions, but DALYs and thus prognosis do differ. Several major conclusions can be drawn from these results. One is that prognosis differs even though prevalence does not. Another is that schizophrenia is not a region-specific disorder. A third is that the reason that prevalence does not differ among regions could be due to biological causes of schizophrenia being more powerful than environmental causes. A fourth is that the reasons that prognosis differs in different regions are plentiful, but can all be derived from social support and community. The implications of these conclusions can be used to better the prognosis of people with schizophrenia worldwide, but further cross-cultural research in underrepresented countries is essential.
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