Дисертації з теми "Matching rates"
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1
Furlan, Benjamin, Martin Gächter, Bob Krebs, and Harald Oberhofer. "Democratization and real exchange rates." Wiley, 2016. http://dx.doi.org/10.1111/sjpe.12088.
Анотація:
In this article, we combine two so far separate strands of the economic literature and argue that democratization leads to a real exchange rate appreciation. We test this hypothesis empirically for a sample of countries observed from 1980 to 2007 by combining a difference-in-difference approach with propensity score matching estimators. Our empirical results reveal a strong and significant finding: democratization causes real exchange rates to appreciate. Consequently, the ongoing process of democratization observed in many parts of the world is likely to reduce exchange rate distortions.
2
Olsen, Karl R. "Matching military skills to civilian jobs : does military training enhance veteran's civilian wage rates? /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1995. http://handle.dtic.mil/100.2/ADA295241.
Анотація:
Thesis (M.S. in Management) Naval Postgraduate School, March 1995.Thesis advisor(s): Stephen L. Mehay, Julie A. Dougherty. "March 1995." Includes bibliographical references. Also available online.
3
Chen, Hanyi. "Probabilistic matching systems : stability, fluid and diffusion approximations and optimal control." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/10570.
Анотація:
In this work we introduce a novel queueing model with two classes of users in which, instead of accessing a resource, users wait in the system to match with a candidate from the other class. The users are selective and the matchings occur probabilistically. This new model is useful for analysing the traffic in web portals that match people who provide a service with people who demand the same service, e.g. employment portals, matrimonial and dating sites and rental portals. We first provide a Markov chain model for these systems and derive the probability distribution of the number of matches up to some finite time given the number of arrivals. We then prove that if no control mechanism is employed these systems are unstable for any set of parameters. We suggest four different classes of control policies to assure stability and conduct analysis on performance measures under the control policies. Contrary to the intuition that the rejection rate should decrease as the users become more likely to be matched, we show that for certain control policies the rejection rate is insensitive to the matching probability. Even more surprisingly, we show that for reasonable policies the rejection rate may be an increasing function of the matching probability. We also prove insensitivity results related to the average queue lengths and waiting times. Further, to gain more insight into the behaviour of probabilistic matching systems, we propose approximation methods based on fluid and diffusion limits using different scalings. We analyse the basic properties of these approximations and show that some performance measures are insensitive to the matching probability agreeing with the results found by the exact analysis. Finally we study the optimal control and revenue management for the systems with the objective of profit maximization. We formulate mathematical models for both unobservable and observable systems. For an unobservable system we suggest a deterministic optimal control, while for an observable system we develop an optimal myopic state dependent pricing.
4
Oliveira, Gabriela Barbosa Sobral de. "The evolutionary origins of impedance-matching hearing in Archosauria." Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2014. http://dx.doi.org/10.18452/17065.
Анотація:
Das impedanzwandelnde Hören ist eine wichtige Verfeinerung des Gehörsystems der Tetrapoden indem es einen Energieverlust während der Schallübertragung vermeidet. Anatomisch ist es durch eine Unterteilung des Foramen Metoticum in eine vordere Fenestra Pseudorotunda und ein hinteres Vagus Foramen charakterisiert. Dieses System trat mehrmals unabhängig in Amniota auf, und obwohl schon vorher vermutet wurde, dass es eine Homoplasie für Archosauria darstellt, wurde diese Hypothese bisher noch nicht geprüft. Demnach wurden 17 Hirnschädel Merkmale für 111 Taxa kodiert und auf einem informellen Supertrees optimiert. Die Analyse ergab, dass die Fenestra Pseudorotunda unbhängig acht Mal in Archosauria auftrat, mit fünf Umkehrungen. Während dieses Merkmal plastisch für Dinosauria ist, es trat nur einmal in Pseudosuchia auf. Eine Tree Shape-Analyse ergab, dass sechs Verschiebungen in den Diversifizierungsraten in Pseudosuchia und sieben in Dinosauria zu finden sind, von denen nur die der Ornithischia mit der Fenestra Pseudorotunda in Beziehung stehen. Viele Zustandsveränderungen erfolgen an der Basis der Dinosauria aber bei Pseudosuchia sind diese vor der Entstehung der Crocodyliformes und an der Basis der Notosuchia und Thalattosuchia konzentriert. Die Korrelationen zwischen Zustandsveränderungen und Verschiebungen sind höher in Dinosauria, während bei Pseudosuchia nur Mesoeucrocodylia eine ähnliche Anzahl aufweist. Daraus folgt, dass das impedanzwandelnde Hören nicht homolog in Archosauria ist, und dass es nicht als Schlüsselinnovation zur Erklärung der Vielfalt betrachtet werden kann, obwohl es eine Rolle in der Diversifizierung der Ornithischia spielte. Insgesamt ist die Anatomie des Hirnschädels der Dinosauria plastischer als die der Pseudosuchia. Die Positionierung des Pterygoid-Quadratum-Komplexes an die Seitenwand des Hirnschädels in Crocodyliformes stellt eine anatomische Beschränkung dar, welche nur von Notosuchia und Thalattosuchia durchbrochen wurde.Impedance-matching hearing is considered an important refinement of the auditory system of tetrapods because it reduces energy loss during sound transmission. Anatomically, it is characterized by the sub-division of the metotic foramen into a posterior vagus foramen and an anterior fenestra pseudorotunda. Impedance-matching hearing has evolved independently in several tetrapod groups including archosaurs and although it has been suggested that it represents a homoplasy, this hypothesis has never been tested. Therefore, 17 braincase characters were coded for 111 taxa and mapped on an informal supertree. Optimization of the characters revealed that the fenestra pseudorotunda appeared eight times independently in Archosauria, with five reversals. While this character is plastic in dinosaurs, it appeared only once in pseudosuchians. A tree-shape analysis revealed that pseudosuchians had six shifts in diversification rates, while dinosaurs had seven. Of these, only ornithischian ones are correlated to the appearance of impedance-matching hearing. Many of the overall state changes occur at the origin of major dinosaurian clades, but for pseudosuchians they are concentrated prior to the origin of Crocodyliformes and at the origin of Notosuchia and Thalattosuchia. The overall number of correspondences between character state changes and shifts in diversification rates is higher for dinosaurs, whereas in Pseudosuchia only Mesoeucrocodylia has a similar amount. It is thus possible to conclude that impedance-matching hearing is not homologous for archosaurs, and that it cannot be considered a key innovation triggering diversification. However, it may have played some role in ornithischian diversification. In general, the braincase anatomy of dinosaurs is more plastic than that of pseudosuchians. The abutting of the pterygo-quadrate complex against the lateral braincase wall was a strong anatomical constraint for crocodyliforms broken only by notosuchians and thalatosuchians.
5
Berry, Meredith Steele. "Reinforcer Magnitude and Resistance to Change of Forgetting Functions and Response Rates." DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1269.
Анотація:
The present experiment was conducted to investigate the effects of reinforcer magnitude on resistance to disruption of remembering and response rates. Pigeons were exposed to a variable-interval (VI), delayed-matching-to-sample procedure (DMTS) with two components (rich and lean). Specifically, completion of a VI 20 second (s) multiple schedule resulted in DMTS trials in both components. In a DMTS trial, a choice of one of two comparison stimuli (e.g., blue key) results in reinforcement if the choice matches some property of the sample stimulus presented previously. Sample and comparison stimuli are separated by a delay. Four delays (0.1, 4, 8, and 16 s) were used between the sample and comparison stimuli in the study. The difference between rich and lean components was the length of hopper duration following a correct response. The probability of reinforcement following a correct response in both components was .5. Each pigeon was exposed to 50 sessions of initial baseline and then 30 sessions of baseline between each disruptive condition (extinction, intercomponent interval [ICI] food, lighting the houselight during delays, and prefeeding). Separable aspects of the forgetting functions (initial discriminability and rate of forgetting) were examined by determining accuracy at each delay. During baseline, response rates were higher in the rich component relative to the lean. Accuracy decreased as delay increased in both rich and lean components, and accuracy was consistently higher in the rich relative to the lean component. During disruptive conditions, extinction, ICI food, and prefeeding disrupted response rates, but lighting the houselight during the delays had little effect. During the DMTS portion of the procedure, extinction and prefeeding decreased initial discriminability and lighting the houselight during the delay increased rate of forgetting. Intercomponent food had little effect on accuracy. Accuracy in the rich component was more resistant to disruption relative to the lean component during extinction. These results indicate that certain disruptors do not have the same disruptive effect across response rates and accuracy (e.g., ICI food). These data also suggest that when systematic differences in accuracy between rich and lean components are revealed, performance in the rich component tends to be more resistant to disruption.
6
Subramanian, Shiva Shankar [Verfasser], Andreas [Akademischer Betreuer] Herkersdorf, Ulf [Gutachter] Schlichtmann, and Andreas [Gutachter] Herkersdorf. "Memory Efficient Signature Matching in Deep Packet Inspection Applications at Line Rates / Shiva Shankar Subramanian ; Gutachter: Ulf Schlichtmann, Andreas Herkersdorf ; Betreuer: Andreas Herkersdorf." München : Universitätsbibliothek der TU München, 2019. http://d-nb.info/1202921906/34.
7
Begeot, Jocelyn. "Autour de la stabilité de différents modèles d'appariements aléatoires." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0201.
Анотація:
Les modèles d'appariements aléatoires représentent de nombreux systèmes stochastiques concrets dans lesquels des éléments de différentes classes sont appariés selon des règles de compatibilités spécifiées. Par exemple, on peut citer les systèmes dédiés à l'allocation d'organes, les sites de recherche d'emplois, de logements, etc. De tels modèles sont toujours associés à un triptyque d'éléments : un graphe connexe, dit de compatibilités, dont les sommets représentent les classes des éléments pouvant entrer dans le systèmeet dont chaque arête relie deux classes compatibles, une politique d'appariements permettant de décider, en cas d'incertitude, quels appariements vont s'effectuer à l'intérieur du système, et un taux d'arrivées selon lequel les éléments entrent en son sein. Dans cette thèse, nous considérons des graphes généralisés, c'est-à-dire que l'on autorise l'appariement de deux éléments de la même classe, et nous étendons donc à ce cadre certains résultats déjà connus dans le cas de graphes simples. La stabilité d'un système régi par un modèle d'appariements est une propriété très importante. En effet, elle assure que les admissions au sein du système étudié sont contrôlées de sorte que les éléments ne restent pas bloqués à l'intérieur et que leur nombre n'augmente pas indéfiniment. Il est donc essentiel que le taux d'arrivées des éléments permette au système d'être stable. Dans ce manuscrit, nous caractérisons de manière algébrique cette zone de stabilité pour certains modèles d'appariements (généraux, généraux avec abandons, bipartis, bipartis étendus) ou de files d'attente, dites skill-based. Par ailleurs, nous démontrons que la politique d'appariements dite First Come, First Matched (FCFM) possède la propriété d'être maximale (généralisée), c'est-à-dire que la zone de stabilité du modèle d'appariements général associé à un graphe de compatibilités et à une politique quelconque est toujours incluse dans celle associée à ce même graphe et à FCFM. Notons que cette dernière coïncide alors avec un ensemble de mesures défini par des conditions purement algébriques. Dans ce cas, la question de l'étude des mesures permettant la stabilité des systèmes régis par un modèle d'appariements revient donc à celle, plus élémentaire, de la caractérisation d'un ensemble déterministe. Nous donnons alors un moyen de construction (simple) des mesures appartenant à celui-ci, ce qui peut s'avérer très utile pour calibrer le contrôle d'accès au système. En effet, la vérification algorithmique qu'une mesure quelconque vérifie ces conditions algébriques nécessite un nombre d'opérations polynomial en le nombre de sommets du graphe, et devient donc très coûteuse à mesure que ce cardinal augmente. Nous explicitons également, sous une forme produit, l'expression de la loi stationnaire de l'évolution temporelle du contenu d'un système stable régi par un modèle d'appariements général et sous la politique FCFM, permettant, notamment, de calculer explicitement des caractéristiques à l'équilibre de systèmes concrets et d'estimer leurs performances en temps long. On peut ainsi, par exemple, calculer la taille moyenne à l'équilibre d'une liste d'attente dans le cadre de dons croisés de reins, ou encore, estimer le temps moyen d'attente sur une interface pair-à-pair ou un site de rencontres.Enfin, les taux d'appariements associés à un modèle d'appariements (général ou biparti étendu) stable sont étudiés. Ils sont définis comme étant les fréquences asymptotiques des appariements réalisés et fournissent un critère de performance des systèmes régis par de tels modèles d'appariements, de même que les propriétés de politique-insensibilité et d'équité de ces taux, qui sont également discutéesStochastic matching models represent many concrete stochastic systems in which elements of different classes are matched according to specified compatibility rules. For example, we can cite systems dedicated to organs allocation, job search sites, housing allocation programs, etc. Such models are typically associated to a triplet of elements: a connected graph, called compatibility graph, whose vertices represent the classes of elements that can enter the system and whose edges connect two compatible classes, amatching policy which decides the matches to be concretely executed, in case of multiple choices, and an arrival rate according to which the elements enter within it. In this thesis, we consider generalized graphs, meaning that we allow the matching of two elements of the same class, and we therefore extend to this framework some results already known in the case of simple graphs.The stability of a system governed by a matching model is a very important property. It ensures that the admissions within the system under study, are regulated, so that the elements do not accumulate in the system in the long run. It is therefore essential that the arrival rate of the elements allows the system to be stable. In this manuscript, we characterize, algebraically, this stability region for some matching models (general, general with reneging, bipartite, extended bipartite) or skill-based queueing systems.Moreover, we demonstrate that the matching policy called First Come, First Matched (FCFM) has the property of being (generalized) maximal, meaning that the stability region of the general matching model associated with a compatibility graph and with any policy is always included in the one associated with this same graph and ruled by FCFM. Note that this latter then coincides with a set of measures defined by purely algebraic conditions. In this case, the study of stability of the matching model at hand boils down to the more elementary question of characterizing of a deterministic set of measures. We then givea (simple) way to construct the measures belonging to the latter set. This turns out to be very useful for admission control, as checking the algebraic conditions requires a number of operations which is polynomial in the number of vertices of the considered compatibility graph, and therefore becomes very expensive as the number of vertices grows large.We also give, in a product form, the expression of the stationary distribution of the number-in-system process of a stable system governed by a general matching model and under the FCFM policy, allowing, in particular, to explicitly calculate characteristics at equilibrium of concrete systems and to estimate their long-time performance. We can thus, for example, calculate the size average at equilibrium of a waiting list in the case of cross-donation of kidneys, or even, estimate the average waiting time on a peer-to-peerinterface or on a dating website.Finally, the matching rates associated with a stable matching model (general or extended bipartite) are studied. They are defined as the asymptotic frequencies of the executed respective matchings, and provide an insightful performance criterion for the corresponding matching systems, as well as the policy-insensitivity and fairness properties of the matching rates, which are also discussed
8
Diallo, Ibrahima. "Some topics in mathematical finance: Asian basket option pricing, Optimal investment strategies." Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210165.
Анотація:
This thesis presents the main results of my research in the field of computational finance and portfolios optimization. We focus on pricing Asian basket options and portfolio problems in the presence of inflation with stochastic interest rates.In Chapter 2, we concentrate upon the derivation of bounds for European-style discrete arithmetic Asian basket options in a Black and Scholes framework.We start from methods used for basket options and Asian options. First, we use the general approach for deriving upper and lower bounds for stop-loss premia of sums of non-independent random variables as in Kaas et al. [Upper and lower bounds for sums of random variables, Insurance Math. Econom. 27 (2000) 151–168] or Dhaene et al. [The concept of comonotonicity in actuarial science and finance: theory, Insurance Math. Econom. 31(1) (2002) 3–33]. We generalize the methods in Deelstra et al. [Pricing of arithmetic basket options by conditioning, Insurance Math. Econom. 34 (2004) 55–57] and Vanmaele et al. [Bounds for the price of discrete sampled arithmetic Asian options, J. Comput. Appl. Math. 185(1) (2006) 51–90]. Afterwards we show how to derive an analytical closed-form expression for a lower bound in the non-comonotonic case. Finally, we derive upper bounds for Asian basket options by applying techniques as in Thompson [Fast narrow bounds on the value of Asian options, Working Paper, University of Cambridge, 1999] and Lord [Partially exact and bounded approximations for arithmetic Asian options, J. Comput. Finance 10 (2) (2006) 1–52]. Numerical results are included and on the basis of our numerical tests, we explain which method we recommend depending on moneyness and time-to-maturity
In Chapter 3, we propose some moment matching pricing methods for European-style discrete arithmetic Asian basket options in a Black & Scholes framework. We generalize the approach of Curran M. (1994) [Valuing Asian and portfolio by conditioning on the geometric mean price”, Management science, 40, 1705-1711] and of Deelstra G. Liinev J. and Vanmaele M. (2004) [Pricing of arithmetic basket options by conditioning”, Insurance: Mathematics & Economics] in several ways. We create a framework that allows for a whole class of conditioning random variables which are normally distributed. We moment match not only with a lognormal random variable but also with a log-extended-skew-normal random variable. We also improve the bounds of Deelstra G. Diallo I. and Vanmaele M. (2008). [Bounds for Asian basket options”, Journal of Computational and Applied Mathematics, 218, 215-228]. Numerical results are included and on the basis of our numerical tests, we explain which method we recommend depending on moneyness and
time-to-maturity.
In Chapter 4, we use the stochastic dynamic programming approach in order to extend
Brennan and Xia’s unconstrained optimal portfolio strategies by investigating the case in which interest rates and inflation rates follow affine dynamics which combine the model of Cox et al. (1985) [A Theory of the Term Structure of Interest Rates, Econometrica, 53(2), 385-408] and the model of Vasicek (1977) [An equilibrium characterization of the term structure, Journal of Financial Economics, 5, 177-188]. We first derive the nominal price of a zero coupon bond by using the evolution PDE which can be solved by reducing the problem to the solution of three ordinary differential equations (ODE). To solve the corresponding control problems we apply a verification theorem without the usual Lipschitz assumption given in Korn R. and Kraft H.(2001)[A Stochastic control approach to portfolio problems with stochastic interest rates, SIAM Journal on Control and Optimization, 40(4), 1250-1269] or Kraft(2004)[Optimal Portfolio with Stochastic Interest Rates and Defaultable Assets, Springer, Berlin].
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
9
Li, Tuo. "Fingerprint Identification by Improved Method of Minutiae Matching." Miami University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=miami1484672769912832.
10
Thomas, Rhiannon D. "Olfactory matching-to-sample in rats using a novel apparatus /." Electronic version (PDF), 2006. http://dl.uncw.edu/etd/2006/thomasr/rhiannonthomas.pdf.
11
Penã, Tracy M. "Generalized identity matching-to-sample in rats using olfactory stimuli /." Electronic version (PDF), 2003. http://dl.uncw.edu/etd/2003/penat/tracypena.html.
12
Poerstel, L. Brooke. "Evaluating equivalence relations in rats using an olfactory matching-to-sample procedure /." Electronic version (PDF), 2007. http://dl.uncw.edu/etd/2007-3/poerstell/laurelpoerstel.pdf.
13
Lefever, Timothy W. "Effects of olanzapine on olfactory delayed matching-to-sample in rats." View electronic thesis (PDF), 2009. http://dl.uncw.edu/etd/2009-3/lefevert/timothylefever.pdf.
14
Indra, Isara. "Very low bit rate video coding using adaptive nonuniform sampling and matching pursuit." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/15779.
15
Elton, Mark David. "Matching feedback with operator intent for efficient human-machine interface." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/50152.
Анотація:
Various roles for operators in human-machine systems have been proposed. This thesis shows that all of these views have in common the fact that operators perform best when given feedback that matches their intent. Past studies have shown that position control is superior to rate control except when operating large-workspace and/or dynamically slow manipulators and for exact tracking tasks. Operators of large-workspace and/or dynamically slow manipulators do not receive immediate position feedback. To remedy this lack of position feedback, a ghost arm overlay was displayed to operators of a dynamically slow manipulator, giving feedback that matches their intent. Operators performed several simple one- and two-dimensional tasks (point-to-point motion, tracking, path following) with three different controllers (position control with and without a ghost, rate control) to indicate how task conditions influence operator intent. Giving the operator position feedback via the ghost significantly increased performance with the position controller and made it comparable to performance with the rate control. These results were further validated by testing coordinated position control with and without a ghost arm and coordinated rate control on an excavator simulator. The results show that position control with the ghost arm is comparable, but not superior to rate control for the dynamics of our excavator example. Unlike previous work, this research compared the fuel efficiencies of different HMIs, as well as the time efficiencies. This work not only provides the design law of matching the feedback to the operator intent, but also gives a guideline for when to choose position or rate control based on the speed of the system.
16
Spaulding, Aleigha, Jessica R. Barbee, Nathan L. Hale, Shimin Zheng, Michael G. Smith, Edward Francis Leinaar, and Amal Jamil Khoury. "Analysis of Birth Rate and Predictors Using Linear Regression Model and Propensity Score Matching Method." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/35.
Анотація:
Evaluating the effectiveness of an intervention can pose challenges if there is not an adequate control group. The effects of the intervention can be distorted by observable differences in the characteristics of the control and treatment groups. Propensity score matching can be used to confirm the outcomes of an intervention are due to the treatment and not other characteristics that may also explain the intervention effects. Propensity score matching is an advanced statistical technique that uses background information on the characteristics of the study population to establish matched pairs of treated participants and controls. This technique improves the quality of control groups and allowing for a better evaluation of the true effects of an intervention. The purpose of this study was to implement this technique to derive county-level matches across the southeastern United States for existing counties within a single state where future statewide initiatives are planned. Statistical analysis was performed using SAS 9.4 (Cary, NC, USA). A select set of key county-level socio-demographic measures theoretically relevant for deriving appropriate matches was examined. These include the proportion of African Americans in population, population density, and proportion of the female population below poverty level. To derive the propensity-matched counties, a logistic regression model with the state of primary interest as the outcome was conducted. The baseline covariates of interest were included in the model and used to predict the probability of a county being in the state of primary interest; this acts as the propensity score used to derive matched controls. A caliper of 0.2 was used to ensure the ratio of the variance of the linear propensity score in the control group to the variance of the linear propensity score in the treatment group is close to 1. The balance of covariates before and after the propensity score matching were assessed to determine if significant differences in each respective covariate persisted after the propensity score matching. Before matching, a significant difference was found in the proportion of African Americans in control group (21.08%, n=3,450) and treatment group (36.95%, n=230) using the t-test (P<0.0001). The percent of females below poverty level showed significant difference between control and treatment group (P=0.0264). The t-test of population density also showed significant differences between the groups (P=0.0424). After matching, the mean differences for the treated-control groups were all zero for these three covariates and the characteristics were no longer showing any significant differences between the two groups. This study found that the use of propensity score matching methods improved the accuracy of matched controls. Ensuring that the control and treatment counties have statistically similar characteristics is important for improving the rigor of future studies examining county-level outcomes. Propensity score matching does not account for unobserved differences between the treatment and control groups that may affect the observed outcomes; however, it does ensure that the observable characteristics between the groups are statistically similar.This method reduces the threat to internal validity that observable characteristics pose on interventions by matching for these potentially confounding characteristics.
17
Minnenok, Lindsay R. "The matching of relative heart rate and VOp2s during graded exercise testing in healthy adults." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1164856.
Анотація:
Exercise prescription intensity is traditionally defined using a target heart rate (HR) as a surrogate measure of oxygen uptake (V02). The ACSM Guidelines recommends the use of a percentage of the maximal HRR because it is thought to match a similar percentage of maximal V02 (%V02max). However, several recent studies have challenged the notion that a given percentage of MHRR matches with the same percentage of V02max in older subjects. The purpose of this study was to assess the difference between percentages of MHRR and V02ma, and evaluate the influence of age on the agreement between these two variables across a range of exercise intensities. The sample included 530 subjects (232 men and 298 women, mean ages of 46.6 + 11.7 years and 43.3 + 11.3 years respectively) who completed a maximal treadmill test to volitional fatigue using the BSU/Bruce Ramp protocol. Heart rate and V02 data from minutes 3, 6, and 9 were converted into percentages of MHRR and V02mai,. Subjects were excluded from the analysis if they failed to achieve an RER,„a,,>1.0. Minutes 3, 6, and 9 represented 45.2 ± 11, 66.0 ± 15, and 83.1 ± 12% of VO2.x, respectively. A one-way ANOVA showed that statistically significant differences existed between the treatment means of relative intensity at minutes 3, 6, and 9 at a p-value of <0.05. The influence of age was assessed by correlation with the difference between percentages of MHRR and VO2max at minutes 3, 6, and 9. In addition, younger (<60 years of age) and older (>60 years of age) subjects were compared using an unpaired t-test. The association between age and the difference between percentages of HRR and VO2max were -0.24, -0.22, and - 0.26 at minutes 3, 6, and 9, respectively. The difference in the relative intensities of HRR and VO2max was greater for older subjects at minutes 3 and 6 (-7.0 vs. -2.2, -3.2 vs. -0.8%) but was smaller at minute 9 (-0.1 vs. -3.2%). A Scheffe post-hoc analysis was used to compare the differences between the treatment means of relative intensity. In conclusion, these results confirm the notion that percentages of MHRR. tend to underestimate percentages of VO2max in older subjects, however the differences observed within the present study were smaller than those reported previously. The small but statistically differences between the techniques would not appear to invalidate the use of percentages of MHRR as surrogate markers of percentages of VO2max in these subjects.School of Physical Education
18
Albertazzi, Victoria Boni. "Um procedimento para o estabelecimento de discriminações condicionais com o responder do sujeito como estímulo modelo." Pontifícia Universidade Católica de São Paulo, 2013. https://tede2.pucsp.br/handle/handle/16704.
Анотація:
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Previous issue date: 2013-05-23Conselho Nacional de Desenvolvimento Científico e Tecnológico
Operant behavior can be placed under stimulus control, and the relationship between discriminated responding and such stimuli can also be controlled by other stimuli, generating the behavioral process named conditional discrimination. Utilizing a rat as a subject, in order to study if it s own behavior could be used as conditional stimulus, controlling choice behavior in a simulateneous discrimination, a procedure was planed based on the proposal by Lionello-DeNolf and Urcuioli (2003). After preliminary training, central lever pressing was placed under the control of a buzzer, in a procedure in which responses emmited in tone cycle accessed a reinforcer (water) and terminated the presentation of the tone, with mean intertrial intervals (ITIs) of initially 30 seconds (range 15-45s), and passing, after two sessions, for 10 seconds mean (range 5-15s). The ratio of lever presses required for water access was gradually increased, and, after reaching FR10, a mixed schedule training was implemented, in which trials with requirements of one or 10 responses were randomically presented. The subject was then placed in a matching-to-sample situation, in which two other levers were presented, and the behavior established in the previous phase accessed comparison stimuli: a blinking and a steady lights, which alternated positions randomically. With the introduction of such condition, central lever press behavior deteriorated; in trials in which comparison stimuli were accessed, choice behavior seemed to be under the control of the position of the stimuli. The role of the ITIs duration in the establishment of simple discriminations was discussed, as well as diferences in the results of such procedures with pigeons and rats
O comportamento operante pode ser colocado sob controle de estímulos antecedentes, e a relação entre o responder discriminado e tais estímulos resultante desse processo pode, por sua vez, ser controlada por outros estímulos, gerando o processo comportamental chamado de discriminação condicional. Utilizando-se de um rato como sujeito, a fim de se estudar se o responder do mesmo poderia servir de estímulo condicional, controlando o comportamento de escolha em uma situação de discriminação simultânea, foi elaborado um procedimento com base no proposto por Lionello-DeNolf e Urcuioli (2003). Após passar por fases preliminares de treino ao bebedouro e seleção de pressão à barra central, esse responder foi colocado sob controle de um tom, em um procedimento no qual o responder em períodos de tom acessava o reforçador e terminava a apresentação do tom, com intervalos entre tentativas (ITIs) tendo inicialmente média de 30 segundos (amplitude 15-45s), e passando, após duas sessões, para média de 10 segundos (amplitude 5-15s). A razão de pressões à barra requeridas para acessar gotas de água foi aumentada, e, após chegar em FR10, foi feito um treino em esquemas mistos, no qual se alternavam, de maneira randômica, tentativas nas quais a água era liberada em CRF e tentativas nas quais a água era liberada em FR10. O sujeito foi então colocado em uma situação experimental de matching-to-sample, na qual foram apresentadas duas outras barras na caixa, e o comportamento estabelecido na fase anterior acessava estímulos comparação: uma luz constante e uma piscante, que alternavam em posição. Com a introdução do procedimento, o responder do sujeito na barra central se deteriorou; nas tentativas em que conseguiu acessar os estímulos comparação, seu comportamento de escolha pareceu estar sob controle da posição dos estímulos. Discute-se o papel do tamanho dos ITIs no estabelecimento das discriminações simples, bem como diferenças nos resultados do procedimento com pombos e ratos
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Buchta, Martin. "Řízení kurzového rizika v mezinárodním obchodě." Master's thesis, Vysoká škola ekonomická v Praze, 2009. http://www.nusl.cz/ntk/nusl-16565.
Анотація:
Diploma thesis is concerned with foreign exchange risk management in terms of international trade. It deals with types of foreign exchange rate risk (transaction exposure, economic exposure, translation exposure) and their influence on business activity. Diploma thesis also focuses on the possibility of future foreign exchange rate's prediction. The main part of the thesis is devoted to various methods of foreign exchange rate risk management. These methods are analysed under two main groups, internal methods and external methods. Under internal methods, following techniques are analysed: netting, matching, leading and lagging, currency diversification, choice of invoicing currency and pricing policy. External methods focus on the use of financial derivatives, specifically currency forwards, currency futures, currency option and currency swaps. Analysis of exchange rate risk management using financial derivatives is supported with illustrative examples.
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Burns, Stephanie Tursic. "The Predictive Validity of Person Matching Methods in Interest Measurement." Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1327781557.
21
Arwini, Saleh. "Improving the convergence rate of seismic history matching with a proxy derived method to aid stochastic sampling." Thesis, Heriot-Watt University, 2013. http://hdl.handle.net/10399/2651.
Анотація:
History matching is a very important activity during the continued development and management of petroleum reservoirs. Time-lapse (4D) seismic data provide information on the dynamics of fluids in reservoirs, relating variations of seismic signal to saturation and pressure changes. This information can be integrated with history matching to improve convergence towards a simulation model that predicts available data. The main aim of this thesis is to develop a method to speed up the convergence rate of assisted seismic history matching using proxy derived gradient method. Stochastic inversion algorithms often rely on simple assumptions for selecting new models by random processes. In this work, we improve the way that such approaches learn about the system they are searching and thus operate more efficiently. To this end, a new method has been developed called NA with Proxy derived Gradients (NAPG). To improve convergence, we use a proxy model to understand how parameters control the misfit and then use a global stochastic method with these sensitivities to optimise the search of the parameter space. This leads to an improved set of final reservoir models. These in turn can be used more effectively in reservoir management decisions. To validate the proposed approach, we applied the new approach on a number of analytical functions and synthetic cases. In addition, we demonstrate the proposed method by applying it to the UKCS Schiehallion field. The results show that the new method speeds up the rate of convergence by a factor of two to three generally. The performance of NAPG is much improved by updating the regression equation coefficients instead of keeping it fixed. In addition, we found that the initial number of models to start NAPG or NA could be reduced by using Experimental Design instead of using random initialization. Ultimately, with all of these approaches combined, the number of models required to find a good match reduced by an order of magnitude. We have investigated the criteria for stopping the SHM loop, particularly the use of a proxy model to help. More research is needed to complete this work but the approach is promising. Quantifying parameter uncertainty using NA and NAPG was studied using the NA-Bayes approach (NAB). We found that NAB is very sensitive to misfit magnitude but otherwise NA and NAPG produce similar uncertainty measures.
22
Stagner, Jessica P. "INVESTIGATION OF THE MONTY HALL DILEMMA IN PIGEONS AND RATS." UKnowledge, 2013. http://uknowledge.uky.edu/psychology_etds/31.
Анотація:
In the Monty Hall Dilemma (MHD), three doors are presented with a prize behind one and participants are instructed to choose a door. One of the unchosen doors is then shown to not have the prize and the participant can choose to stay with their door or switch to the other one. The optimal strategy is to switch. Herbranson and Schroeder (2010) found that humans performed poorly on this task, whereas pigeons learned to switch readily. However, we found that pigeons learned to switch at level only slightly above humans. We also found that pigeons stay nearly exclusively when staying is the optimal strategy and when staying and switching are reinforced equally (Stagner, Rayburn-Reeves, & Zentall, 2013).
In Experiment 1, rats were trained under these same conditions to observe if possible differences in foraging strategy would influence performance on this task. In Experiment 2, pigeons were trained in an analogous procedure to better compare the two species. We found that both species were sensitive to the overall probability of reinforcement, as both switched significantly more often than subjects in a group that were reinforced equally for staying and switching and a group that was reinforced more often for staying. Overall, the two species performed very similarly within the parameters of the current procedure.
23
Toivonen, T. (Tuukka). "Efficient methods for video coding and processing." Doctoral thesis, University of Oulu, 2008. http://urn.fi/urn:isbn:9789514286957.
Анотація:
Abstract
This thesis presents several novel improvements to video coding algorithms, including block-based motion estimation, quantization selection, and video filtering. Most of the presented improvements are fully compatible with the standards in general use, including MPEG-1, MPEG-2, MPEG-4, H.261, H.263, and H.264.
For quantization selection, new methods are developed based on the rate-distortion theory. The first method obtains locally optimal frame-level quantization parameter considering frame-wise dependencies. The method is applicable to generic optimization problems, including also motion estimation. The second method, aimed at real-time performance, heuristically modulates the quantization parameter in sequential frames improving significantly the rate-distortion performance. It also utilizes multiple reference frames when available, as in H.264. Finally, coding efficiency is improved by introducing a new matching criterion for motion estimation which can estimate the bit rate after transform coding more accurately, leading to better motion vectors.
For fast motion estimation, several improvements on prior methods are proposed. First, fast matching, based on filtering and subsampling, is combined with a state-of-the-art search strategy to create a very quick and high-quality motion estimation method. The successive elimination algorithm (SEA) is also applied to the method and its performance is improved by deriving a new tighter lower bound and increasing it with a small constant, which eliminates a larger part of the candidate motion vectors, degrading quality only insignificantly. As an alternative, the multilevel SEA (MSEA) is applied to the H.264-compatible motion estimation utilizing efficiently the various available block sizes in the standard.
Then, a new method is developed for refining the motion vector obtained from any fast and suboptimal motion estimation method. The resulting algorithm can be easily adjusted to have the desired tradeoff between computational complexity and rate-distortion performance. For refining integer motion vectors into half-pixel resolution, a new very quick but accurate method is developed based on the mathematical properties of bilinear interpolation.
Finally, novel number theoretic transforms are developed which are best suited for two-dimensional image filtering, including image restoration and enhancement, but methods are developed with a view to the use of the transforms also for very reliable motion estimation.
24
Anderson, Jesse Glenn Sigrid S. "An examination of the effects of accuracy+rate versus accuracy+observing response training methods on matching-to-sample performance." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3708.
25
Anderson, Jesse. "An examination of the effects of accuracy+rate versus accuracy+observing response training methods on matching-to-sample performance." Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3708/.
Анотація:
The relative efficacy of training procedures emphasizing accuracy versus those which add a rate criterion is a topic of debate. The desired learning outcome is fluent responding, assessed by measures of retention, endurance, stability, and application. The current study examined the effects of these two procedures on fluency outcomes using a matching-to-sample paradigm to train participants to match English to Japanese characters. An explicit FR-3 observing response was added to an accuracy-only condition to assess the extent to which it may facilitate learning. Total time spent responding in practice drills in accuracy-only conditions was yoked to total time spent in drills achieving rate aims in accuracy+rate (AR) conditions. One participant clearly demonstrated superior fluency outcomes after AR training while another displayed superior endurance and stability outcomes after such training. The remaining two participants did not demonstrate significantly different fluency outcomes across conditions.
26
Sandlund, Jonas. "Position-matching and goal-directed reaching acuity of the upper limb in chronic neck pain : associations to self-rated characteristics." Doctoral thesis, Umeå : Gävle : Univ. ; Centre for Musculoskeletal Research, University of Gävle, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1635.
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Nåtman, Jonatan. "The performance of inverse probability of treatment weighting and propensity score matching for estimating marginal hazard ratios." Thesis, Uppsala universitet, Statistiska institutionen, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385502.
Анотація:
Propensity score methods are increasingly being used to reduce the effect of measured confounders in observational research. In medicine, censored time-to-event data is common. Using Monte Carlo simulations, this thesis evaluates the performance of nearest neighbour matching (NNM) and inverse probability of treatment weighting (IPTW) in combination with Cox proportional hazards models for estimating marginal hazard ratios. Focus is on the performance for different sample sizes and censoring rates, aspects which have not been fully investigated in this context before. The results show that, in the absence of censoring, both methods can reduce bias substantially. IPTW consistently had better performance in terms of bias and MSE compared to NNM. For the smallest examined sample size with 60 subjects, the use of IPTW led to estimates with bias below 15 %. Since the data were generated using a conditional parametrisation, the estimation of univariate models violates the proportional hazards assumption. As a result, censoring the data led to an increase in bias.
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Sanaullah, Irum. "Real-time estimation of travel time using low frequency GPS data from moving sensors." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/11938.
Анотація:
Travel time is one of the most important inputs in many Intelligent Transport Systems (ITS). As a result, this information needs to be accurate and dynamic in both spatial and temporal dimensions. For the estimation of travel time, data from fixed sensors such as Inductive Loop Detectors (ILD) and cameras have been widely used since the 1960 s. However, data from fixed sensors may not be sufficiently reliable to estimate travel time due to a combination of limited coverage and low quality data resulting from the high cost of implementing and operating these systems. Such issues are particularly critical in the context of Less Developed Countries, where traffic levels and associated problems are increasing even more rapidly than in Europe and North America, and where there are no pre-existing traffic monitoring systems in place. As a consequence, recent developments have focused on utilising moving sensors (i.e. probe vehicles and/or people equipped with GPS: for instance, navigation and route guidance devices, mobile phones and smartphones) to provide accurate speed, positioning and timing data to estimate travel time. However, data from GPS also have errors, especially for positioning fixes in urban areas. Therefore, map-matching techniques are generally applied to match raw positioning data onto the correct road segments so as to reliably estimate link travel time. This is challenging because most current map-matching methods are suitable for high frequency GPS positioning data (e.g. data with 1 second interval) and may not be appropriate for low frequency data (e.g. data with 30 or 60 second intervals). Yet, many moving sensors only retain low frequency data so as to reduce the cost of data storage and transmission. The accuracy of travel time estimation using data from moving sensors also depends on a range of other factors, for instance vehicle fleet sample size (i.e. proportion of vehicles equipped with GPS); coverage of links (i.e. proportion of links on which GPS-equipped vehicles travel); GPS data sampling frequency (e.g. 3, 6, 30, 60 seconds) and time window length (e.g. 5, 10 and 15 minutes). Existing methods of estimating travel time from GPS data are not capable of simultaneously taking into account the issues related to uncertainties associated with GPS and spatial road network data; low sampling frequency; low density vehicle coverage on some roads on the network; time window length; and vehicle fleet sample size. Accordingly this research is based on the development and application of a methodology which uses GPS data to reliably estimate travel time in real-time while considering the factors including vehicle fleet sample size, data sampling frequency and time window length in the estimation process. Specifically, the purpose of this thesis was to first determine the accurate location of a vehicle travelling on a road link by applying a map-matching algorithm at a range of sampling frequencies to reduce the potential errors associated with GPS and digital road maps, for example where vehicles are sometimes assigned to the wrong road links. Secondly, four different methods have been developed to estimate link travel time based on map-matched GPS positions and speed data from low frequency data sets in three time windows lengths (i.e. 5, 10 and 15 minutes). These are based on vehicle speeds, speed limits, link distances and average speeds; initially only within the given link but subsequently in the adjacent links too. More specifically, the final method draws on weighted link travel times associated with the given and adjacent links in both spatial and temporal dimensions to estimate link travel time for the given link. GPS data from Interstate I-880 (California, USA) for a total of 73 vehicles over 6 hours were obtained from the UC-Berkeley s Mobile Century Project. The original GPS dataset which was broadcast on a 3 second sampling frequency has been extracted at different sampling frequencies such as 6, 30, 60 and 120 seconds so as to evaluate the performance of each travel time estimation method at low sampling frequencies. The results were then validated against reference travel time data collected from 4,126 vehicles by high resolution video cameras, and these indicate that factors such as vehicle sample size, data sampling frequency, vehicle coverage on the links and time window length all influence the accuracy of link travel time estimation.
29
Warren, Kristen Marie. "Multichannel Pulse Oximetry: Effectiveness in Reducing HR and SpO2 error due to Motion Artifacts." Digital WPI, 2016. https://digitalcommons.wpi.edu/etd-theses/1219.
Анотація:
Pulse oximetry is used to measure heart rate (HR) and arterial oxygen saturation (SpO2) from photoplethysmographic (PPG) waveforms. PPG waveforms are highly sensitive to motion artifact (MA), limiting the implementation of pulse oximetry in mobile physiological monitoring using wearable devices. Previous studies have shown that multichannel pulse oximetry can successfully acquire diverse signal information during simple, repetitive motion, thus leading to differences in motion tolerance across channels. In this study, we introduce a multichannel forehead-mounted pulse oximeter and investigate the performance of this novel sensor under a variety of intense motion artifacts. We have developed a multichannel template-matching algorithm that chooses the channel with the least amount of motion artifact to calculate HR and SpO2 every 2 seconds. We show that for a wide variety of random motion, channels respond differently to motion, and the multichannel estimate outperforms single channel estimates in terms of motion tolerance, signal quality, and HR and SpO2 error. Based on 31 data sets of PPG waveforms corrupted by random motion, the mean relative HR error was decreased by an average of 5.6 bpm when the multichannel-switching algorithm was compared to the worst performing channel. The percentage of HR measurements with absolute errors ≤ 5 bpm during motion increased by an average of 27.8 % when the multichannel-switching algorithm was compared to the worst performing channel. Similarly, the mean relative SpO2 error was decreased by an average of 4.3 % during motion when the multichannel-switching algorithm was compared to each individual channel. The percentage of SpO2 measurements with absolute error ≤ 3 % during motion increased by an average of 40.7 % when the multichannel-switching algorithm was compared to the worst performing channel. Implementation of this multichannel algorithm in a wearable device will decrease dropouts in HR and SpO2 measurements during motion. Additionally, the differences in motion frequency introduced across channels observed in this study shows precedence for future multichannel-based algorithms that make pulse oximetry measurements more robust during a greater variety of intense motion.
30
Chen, Xi. "Exploiting BioPortal as Background Knowledge in Ontology Alignment." Miami University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=miami1407331095.
31
Silva, Hélio Rodrigo Serra. "Imunização dos efeitos cíclicos no cálculo das provisões técnicas em ambiente solvência II : counter-cyclical premium e matching premium." Master's thesis, Instituto Superior de Economia e Gestão, 2012. http://hdl.handle.net/10400.5/10800.
Анотація:
Mestrado em Ciências ActuariaisA recente instabilidade dos mercados financeiros contribuiu para o aumento do debate em torno da avaliação das responsabilidades e dos ativos das empresas de seguros e de resseguros. Tal decorre do desvio significativo que os preços de mercado podem sofrer em relação aos fundamentos económicos implícitos, refletindo a aversão ao risco e o interesse próprio dos investidores. Este texto é o relatório de um estágio curricular realizado no Instituto de Seguros de Portugal. O projeto subjacente consistiu no estudo aprofundado de dois inovadores instrumentos, agora propostos pelas instâncias da União Europeia, para a imunização dos efeitos cíclicos no cálculo das provisões técnicas, em ambiente Solvência II: o counter-cyclical premium e o matching premium. Ambos atuam sobre a Estrutura Temporal das Taxas de Juro, mas enquanto que o primeiro é utilizado apenas em períodos de elevado stress financeiro, o outro tem em vista as empresas que utilizam uma estratégia de buy-and-hold de ativos.
The recent instability of financial markets has raised the debate on the area of the valuation of the liabilities and assets of the insurance and reinsurance undertakings. This follows from the significant deviation that market prices may suffer in relation to their implied economic fundamentals, reflecting the risk aversion and self-interest of investors. This internship report explains the insightful study that was developed about two new instruments, as proposed by European Union bodies: the counter-cyclical premium and the matching premium. The purpose is the immunization of cyclical effects in the calculation of technical provisions, under Solvency II environment. They are both added to the risk free interest rate term structure, but while the first is applied only during stressed periods the other can be used whenever insurers take a buy-and-hold strategy, being able to hold the relevant assets until maturity. The internship was with the Portuguese Insurance and Pension Funds Supervisory Authority (Instituto de Seguros de Portugal).
32
Choudhary, Saumya. "On Plasmonic Superradiance, the Scaling Laws of Spontaneous Parametric Downconversion, and the Principles and Recent Advances in Nonlinear Optics." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35132.
Анотація:
This thesis covers three different topics. The first part is a pedagogical review of the basic principles and recent advances in nonlinear optics. It was originally written as a chapter for the proceedings of the “International School of Physics (Enrico Fermi)” summer school on Photonics held in June, 2014. It is included to provide some background information about nonlinear optical processes in general, and is particularly relevant for the third part of this thesis which is based on the second-order nonlinear optical process of spontaneous parametric downconversion.
The second part is based on original research, and deals with superradiance in plasmonic nanostructures. The process of superradiance, as introduced by Dicke in 1954, entails the shortening of the spontaneous emission lifetime of a collection of N quantum emitters as a consequence of the development of a macroscopic dipole moment. Specifically, the lifetime is shortened by a factor of 1/N, and the linewidth is broadened by a factor of N. Such a linewidth dependence has been previously observed in systems of several plasmonic ‘emitters’. However, a clear physical insight into this phenomenon and how it relates to Dicke superradiance has not been shown yet. In this part, we demonstrate by experiment, simulation, and a simple analytical model that Dicke’s superradiance can indeed be observed in a planar array of plasmonic nanoantennas, with a linewidth that scales linearly with the number of nanoantennas within a square wavelength.
The third part is also based on original research, and is based on the scal- ing laws of spontaneous parametric downconversion (SPDC) for a type-I phase- matching configuration. The variation of bi-photon generation rate, heralding efficiency and radiance with parameters such as crystal length, pump focussing and collection waist sizes are examined for collinear and non-collinear emission. The results can be used to maximize the brightness of the SPDC source or increase the heralding efficiency depending on the application.
33
Brückner, Markus. "Essays in Macroeconomics." Doctoral thesis, Universitat Pompeu Fabra, 2010. http://hdl.handle.net/10803/7593.
Анотація:
This thesis consists of three chapters. The first chapter examines empirically the relationshipbetween foreign aid and economic growth in the Least Developed Countries. Instrumental
variables techniques are used to estimate the effect that economic growth has on foreign aid
and to adjust for the reverse causal effect that growth has on aid when estimating the effect that
aid has on growth. The second chapter examines the effects that fiscal expansions have on the
unemployment rate. The chapter presents SVAR evidence for ten OECD countries and builds a
DSGE model with a labor force participation choice and workers' heterogeneity to explain the
empirical findings. The third chapter examines the effects that economic growth has on the
support for extreme political platforms. The chapter provides a theoretical model in favor of
growth effects (as opposed to level effects) on the support for extreme political parties, and
investigates empirically the relationship between growth and extremist votes for 16 OECD
countries.
Esta tesis consiste en tres capítulos. El primer capítulo examina empíricamente la relación entre
la ayuda exterior y crecimiento económico en los países menos adelantados. Técnicas de
variables instrumentales se utilizan para estimar el efecto que el crecimiento económico tiene
sobre la ayuda exterior y para ajustar el efecto de causalidad inversa que el crecimiento tiene en
la ayuda al estimar el efecto que la ayuda tiene sobre el crecimiento. El segundo capítulo
analiza los efectos que las expansiones fiscales tienen sobre la tasa de desempleo. El capítulo
presenta pruebas SVAR para diez países de la OCDE y construye un modelo DSGE con una
participación en la fuerza de trabajo y heterogeneidad de los trabajadores para explicar los
resultados empíricos. El tercer capítulo analiza los efectos que el crecimiento económico tiene
en el apoyo a las plataformas políticas extremas. El capítulo ofrece un modelo teórico a favor
de los efectos del crecimiento (en contraposición a los efectos de nivel) con el apoyo de
partidos políticos de extrema, e investiga empíricamente la relación entre el crecimiento de
votos y extremistas para 16 países de la OCDE.
34
Mayberry, Curtis Lee. "Interface circuits for readout and control of a micro-hemispherical resonating gyroscope." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53116.
Анотація:
Gyroscopes are inertial sensors that measure the rate or angle of rotation. One of the most promising technologies for reaching a high-performance MEMS gyroscope has been development of the micro-hemispherical shell resonator. (μHSR) This thesis presents the electronic control and read-out interface that has been developed to turn the μHSR into a fully functional micro-hemispherical resonating gyroscope (μHRG) capable of measuring the rate of rotation. First, the μHSR was characterized, which both enabled the design of the interface and led to new insights into the linearity and feed-through characteristics of the μHSR. Then a detailed analysis of the rate mode interface including calculations and simulations was performed. This interface was then implemented on custom printed circuit boards for both the analog front-end and analog back-end, along with a custom on-board vacuum chamber and chassis to house the μHSR and interface electronics. Finally the performance of the rate mode gyroscope interface was characterized, showing a linear scale factor of 8.57 mv/deg/s, an angle random walk (ARW) of 34 deg/sqrt(hr) and a bias instability of 330 deg/hr.
35
Singh, Harshvardhan P. "Towards Achieving Highly Parallelized Publish/Subscribe Matching at Line-rates Using Reconfigurable Hardware." Thesis, 2011. http://hdl.handle.net/1807/31445.
Анотація:
We present fpga-ToPSS (Toronto Publish/ Subscribe System), an efficient
FPGA-based middleware platform geared towards high-frequency and low-latency event processing. fpga-ToPSS is built over reconfigurable hardware---FPGAs---to achieve line-rate processing by exploiting
unprecedented degrees of parallelism and potential for pipelining,only available through custom-built, application-specific and low-level logic design.
Furthermore, our middleware solution hosts an event processing engine that is built on a hardware-based packet processor and Boolean
expression matcher. Our middleware vision extends to a wide range of applications including real-time data analytics, intrusion detection, algorithmic trading, targeted advertisement, and (complex) event
processing.
36
Lin, Chih-wei, and 林志威. "LTE Downlink Systems Using Adaptive Rate Matching." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/24577405581166372554.
Анотація:
碩士國立中央大學
通訊工程研究所
99
This thesis focuses on LTE downlink systems with shared channel coding between medium access control layer (MAC) and physical layer, using turbo coding, and hybrid automatic repeat request (HARQ). It made reference to Incremental redundancy type II HARQ (IR Type II HARQ), and proposed adaptive rate matching, Its purpose is not IR Type II HARQ retransmission method, We want to adjust the way through the training code rate, allows the system to adapt to different channel environments. After adjust code rate, LTE systems can save computing time. And we also use OFDM, beamforming technology and simulation in different environments. The simulation results showed that adaptive rate matching can enhance the code rate according to different environments, saving transmission bits, and will not affect the decoding success rate, need to use very few number of HARQ.
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FU, CHEN-YOU, and 傅晨祐. "Improvement on Rate Matching for 5G Polar Codes." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/nhyccb.
Анотація:
碩士國立臺灣科技大學
電子工程系
107
With the development of communication technology, 3GPP NR standards discussions for 5G, polar codes have been adopted as the control channel coding because of its good performance. Although the polar code has the advantage of low block error rates, it has the disadvantage that its code length can only be limited to a power of two, resulting in a large limitation in various applications. In order to be able to choose the code length of the polar code, the fifth-generation mobile communication specification also proposes a rate matching mechanism, which can select the code length to transmit. There are three ways to rate matching, namely puncturing, shortening, and repetition. In this paper, we will only discuss how to improve the two mechanisms of puncturing and shortening in the existing 5G rate matching. The puncturing mechanism works by selecting not to transfer certain bits after coding, so that the effect of decreasing the code length is achieved. Shortening is also achieves the effect of decreasing the code length. The difference between puncturing and shortening is that the values of punctured bits are unknown to the receiver and the values of shortened bits are known in advance. The repetition mechanism works by selecting to retransfer certain bits after coding, so that the effect of extending the code length is achieved. The method we propose is based on the sub-channel reliability estimation by GA(Gaussian Approximation) and the 5G rate matching circular buffer. It turns out that our method achieves a better BLER.
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Lee, Da-Huei, and 李大輝. "Dynamic Element Matching Approaches for Oversampling-Rate and Nyquist-Rate Data Converters." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/97751080152686237249.
Анотація:
博士國立成功大學
電機工程學系碩博士班
96
Data converters have become very important building blocks for integrated circuits (ICs) due to the fast growth of digital signal processing systems recently. Lower cost high-performance data converters are strongly demanded to satisfy the requirements of more complicated system-on-a-chip (SOC) systems. Element mismatch is one of the major impairments for low-cost high-resolution data converters. Dynamic element matching (DEM) approaches have been widely used to suppress the harmonic distortions caused by element mismatches. In this dissertation, several DEM approaches are proposed and analyzed. For oversampling-rate data converters, advancing data weighted averaging (ADWA) is proposed to remedy baseband tone problems of conventional DWA. For Nyquist-rate data converters, random multiple DWA (RMDWA), random incrementing DWA (RIDWA) and randomized thermometer-coding (RTC) are proposed to achieve high spurious-free dynamic range (SFDR) and small maximum output error. Furthermore, an ultra low-cost Nyquist-rate current-steering digital-to-analog converter (DAC) is implemented to experimentally verify the proposed RTC. For oversampling-rate data converters, multibit sigma–delta modulators usually employ the DWA to suppress the element mismatch effect but are plagued by baseband tone problems. The existing DWA-like approaches for solving these problems are categorized in this dissertation as tone-suppressing and tone-transferring approaches. Although tone-transferring approaches can achieve a better signal-to-noise-plus-distortion ratio than tone-suppressing approaches, they may behave unfavorably for input signals with dc components. A flexible DWA-like approach, ADWA, which can achieve both tone-suppressing and tone-transferring functions, is proposed. Moreover, ADWA can be a reconfigurable approach that uses input signal detection schemes to set its configuration. For Nyquist-rate data converters, three DEM approaches are proposed to be used with a proper layout switching scheme in a proposed new DAC structure. RMDWA and RIDWA have randomization and consecutive selection properties. Randomization effectively suppresses harmonic distortions to achieve good SFDR. Consecutive selection obtains small static output errors when it is used with the presented rotated walk switching scheme. The third DEM approach proposed for Nyquist-rate DACs is RTC, which provides randomization, consecutive selection, and low element switching activity properties. In addition to the benefits of the proposed RMDWA and RIDWA, low element switching activity can achieve small dynamic errors caused by element switching. To experimentally verify the proposed RTC, a 14-bit ultra low-cost current-steering DAC is implemented in a 1P6M 0.18-μm 1.8-V CMOS process. The measured SFDR is up to 80dB for single-tone tests at a 10MHz sampling frequency. The measurement results show that the RTC can improve the SFDR by 16dB. The 14-bit current-steering DAC has an active area of less than 0.28-mm2. The active area of the DAC is smaller than those of the state-of-the-art DACs with 14-bit resolution. The active area of the DAC is also smaller than those of other published 12-bit and 10-bit DACs.
39
Reis, Sofia Santos dos. "Um olhar sobre os diplomados: a relação entre área de formação e posto de trabalho, em Portugal." Master's thesis, 2012. http://hdl.handle.net/10071/5465.
Анотація:
Projecto / JEL Classification System: I21, I25Este estudo enquadra-se nos estudos sobre a correspondência entre o nível de escolaridade e o posto de trabalho e centra-se exclusivamente no tipo de correspondência horizontal, em que se estabelece a correspondência entre a área de formação e o posto de trabalho. Procurando assim inovar e demarcar pela diferença ao não seguir a tendência dos estudos focados na correspondência vertical, em que se analisa se os indivíduos estão a ocupar postos de trabalho que correspondem ao seu nível de escolaridade. Os dados utilizados foram fornecidos pelo GEP – Gabinete de Planeamento e Estratégia, do Ministério do Trabalho e Solidariedade Social, provenientes dos Quadros Pessoal, abrangendo um período de dez anos, de 1999 a 2009, com um ano de quebra de série, correspondente a 2001, sendo seleccionados apenas os indivíduos com o ensino superior distribuídos pelas áreas de formação e pelos postos de trabalho. O foco da análise incide no cálculo de taxas de eficácia em duas leituras: sobre o total de diplomados no conjunto dos postos de trabalho da área correspondente e sobre o conjunto de diplomados com um posto de trabalho na sua área de formação no total de diplomados da área correspondente. Os resultados, marcados pela diversidade de resultados entre as diferentes áreas e nos dois tipos de leitura, confirmam taxas de eficácia abaixo dos 50%, em ambas as leituras, indicando que uma maioria significativa de diplomados trabalha fora da sua área de formação. Mediante resultados tão baixos em termos de eficácia, segue-se a problemática da ineficácia de correspondência, com a discussão sobre a concentração de diplomados em postos de trabalho fora das suas áreas, bem como a possível influência das taxas de desemprego das áreas, já que áreas de formação com a taxa de desemprego superior à da eficácia se traduzem num valor elevado de ineficácia, e a hipótese de mobilidade profissional, verificando que não houve um melhoramento da eficácia no decorrer do período em análise.
This study was based on studies of the matching between the level of education and the job and focuses exclusively on horizontal matching type, which establishes the correspondence between the study area and the job. Looking for innovating and demarcating by the difference to not following the trend of the studies focused on vertical matching, it analyzes whether individuals are occupying jobs that match your education level. The data used were provided by the GEP - Planning and Strategy Office, Ministry of Labour and Social Solidarity, from the Personnel Boards, covering a period of ten years, from 1999 to 2009, with one break series year, corresponding to 2001, being selected only individuals with higher education distributed by the study areas and jobs. The focus of the analysis concerns on the calculation of rates of efficacy in two readings: on total graduates in the jobs of the match area and on the number of graduates with a job in their study field in total graduates matching area. The results, marked by the diversity of results between the different areas and the two types of reading, confirm efficacy rates below 50% in both readings, indicating that a significant majority of graduates is working outside their area of training. Through such low results in terms of effectiveness, it follows the issue of ineffectiveness of correspondence with the discussion on the concentration of graduates in jobs outside their areas, as well as the possible influence of unemployment areas, since study areas with unemployment rates higher than the efficiency translate into high value of inefficiency, and mobility hypothesis, indicating that there was an improvement in efficiency, during the period under analysis.
40
Shen, Richar Jyh Sheen, and 沈志賢. "A Fast Predictive Block-Matching Motion Estimation Algorithm for Low Bit-Rate Coding." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/83875101746092077786.
Анотація:
碩士國立中興大學
電機工程學系
88
For low bit-rate video coding, predictive block-matching motion estimation algorithms have been used to replace the logarithmic step search algorithms because the motion vector searching time can be greatly reduced by utilizing the correlation existing in motion vectors. However, these algorithms still suffer from their large computations if the initial prediction is not accurate enough. As a result, the motion vector searching time can vary acutely from frame to frame. In this article, we investigate the correlation among motion vectors (MV). Our study shows that the x component of MV is more related to its vertical neighbor MVs while the y component of MV is more depedent on its horizontal neighbor MVs. Based on the observation, we design a modified three-block median predictor to improve the motion vector predicting accuracy. By employing the predictor, a fast predictive block-matching motion estimation algorithm, the vector search algorithm (VSA), is proposed. Instead of checking all locations in the search area, the VSA only searches locations in the most probable direction. Simulation results indicate that our algorithm is much faster than other fast search algorithms as well as maintaining similar or better performance in terms of mean-square error measurement.
41
Lu, Wei-Yuan, and 呂偉元. "A Low Bitrate Video System Using New Block Matching And Rate Control Schemes." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/92340124721772058595.
42
CHEN, HO-CHIAN, and 陳和謙. "Map Matching for Low-Sampling-Rate GPS Trajectories by Exploring Real-time Moving Directions." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/rxqjq5.
Анотація:
碩士國立中正大學
資訊工程研究所
104
Map matching is the process of matching a series of recorded geographic coordinates (e.g., a GPS trajectory) to a road network. Due to GPS positioning errors and the sampling constraints, the GPS data collected by the GPS device are not precise, and the location of a user can not always be correctly shown on the map. Therefore, map matching is an important preprocessing step for many applications such as navigation systems, traffic flow analysis, and autonomous cars. Unfortunately, most current map-matching algorithms only consider the distance between the GPS points and the road segments, the topology of the road network, and the speed constraint of the road segment to determine the matching results. Moreover, most current map-matching algorithms can not handle the matching problem at junctions. In this paper, we propose a spatio-temporal-direction based matching algorithm (STD-matching) for low-sampling-rate GPS trajectories. STD-matching considers (1) the spatial features such as the distance information and topology of the road network, (2) the speed constraints of the road network, and (3) the real-time moving direction which shows the movement of the user. Moreover, we also reduce the running time by performing GPS clustering, GPS smoothing, and the A* shortest path algorithms. In our experiments, we compare STD-matching with two baseline algorithms, the ST-matching algorithm and the stMM algorithm, using a real data set. The experiment results show that our STD-matching algorithm outperforms the two baseline algorithms in terms of matching accuracy.
43
Shih, Liang-chun, and 石良俊. "Rate-distortion optimization based on quality layer assignment for scalable matching pursuit video coding." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/5ehehf.
Анотація:
碩士國立中山大學
通訊工程研究所
97
Although fine granularity scalability (FGS) video coding based on matching pursuits and bit-plane coding have been proven to have better coding efficiency than discrete-cosine-transform-based FGS at low bit rates, it might not be the most efficient method in terms of rate-distortion optimization (RDO). We propose a rate-distortion optimization FGS video coding by dividing a frame into blocks to generate block-based embedded bit-streams and reorganize the bit-streams into several quality layers according to the rate-distortion slopes. The comparison between FGS matching pursuit video coding and RDO-FGS matching pursuit video coding is shown in the experimental results.
44
Cheng, Li-Jie, and 鄭立傑. "A Link-Adapted Fragment and Rate Matching (FaRM) MAC Protocol for Mobile Ad Hoc Networks." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/96732255557812977502.
Анотація:
碩士淡江大學
資訊工程學系碩士班
94
In the wireless environment, the channel condition varies due to several factors, especially in mobile ad hoc networks. Previous researches use SNR thresholds to determine the channel condition. However, SNR thresholds may not be an accurate decision, especially in a quickly varied environment. This paper proposes a fragment and rate matching (FaRM) MAC protocol for mobile ad hoc networks. In FaRM, stations dynamically detect the current signal-noise-ratio (SNR) to present the channel quality through the control frame exchange. Then FaRM uses Finite State Markov Chain to predict the variation of the channel quality. FaRM therefore can get closer results of the error occurrence in the channel than previous researches. According to the results generated from Finite State Markov Chain, FaRM dynamically selects the transmission rate with an acceptable fragment length. FaRM not only gains better throughput through the selection of high rate, but also increases the reliability by fragmentation. Comparing to other researches, the simulation results show FaRM has better performance, higher transmission reliability and lower transmission delay time by fragmentation according to the prediction of the network.
45
CHEN, PING-SHEN, and 陳丙紳. "Relationship between Different Testing and Judo Matchon Heart Rate." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/35834528917697198409.
Анотація:
碩士國立體育大學
競技與教練科學研究所
102
Relationship between Different Testing and Judo Match on Heart Rate Abstract Research purposes: to explore the relationship between the different test methods and the heartbeat rates of special judo loads. Research Method: the research objects were eight lightweight ((<66 kg) and (<73kg)) university Group A judo players (average age: 21±1.06 years old; height: 171±6.84 cm; weight: 69±5.59 kg; training years: 10±2 years). Each player performed the continuous suplex attack for 10 seconds, the cross run and the 150m speed run. Then, the comparison was made between the Judo match play and 90-second attack in terms of the heartbeat rate. The data were analyzed with the Pearson product-moment correlation and the repeated measures one-way ANOVA. Results: there a correlation between 150m sprint and the test of the 90-second special judo (r2=0.5); the correlation coefficient of the coordination and the special test is r2=0.3; there is a correlation between special judo UKSN and the coordination test (r2=0.7); there is no correlation between special Judo UKSN and the 3m cross run (r2=0.1). Conclusion: the basic and special abilities of all players can be observed from the four-quadrant analysis model. The poor basic judo abilities affects the special athletic performance. In the future training, the sections needing to be strengthened by the players can be clearly known and the predicted basic abilities of the training preparation period can be planned through the four-quadrant analysis model. Keywords: Special judo training, 3m cross run, coordination, 150m
46
Greguson, Lezlee Ann. "Differential effects of reinforcement rate and delay on response allocation a systematic approach utilizing the matching law /." 2008. http://digital.library.okstate.edu/etd/umi-okstate-2803.pdf.
47
Park, Han-Young. "A Hierarchical Multiscale Approach to History Matching and Optimization for Reservoir Management in Mature Fields." Thesis, 2012. http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11779.
Анотація:
Reservoir management typically focuses on maximizing oil and gas recovery from a reservoir based on facts and information while minimizing capital and operating investments. Modern reservoir management uses history-matched simulation model to predict the range of recovery or to provide the economic assessment of different field development strategies. Geological models are becoming increasingly complex and more detailed with several hundred thousand to million cells, which include large sets of subsurface uncertainties. Current issues associated with history matching, therefore, involve extensive computation (flow simulations) time, preserving geologic realism, and non-uniqueness problem. Many of recent rate optimization methods utilize constrained optimization techniques, often making them inaccessible for field reservoir management. Field-scale rate optimization problems involve highly complex reservoir models, production and facilities constraints and a large number of unknowns.
We present a hierarchical multiscale calibration approach using global and local updates in coarse and fine grid. We incorporate a multiscale framework into hierarchical updates: global and local updates. In global update we calibrate large-scale parameters to match global field-level energy (pressure), which is followed by local update where we match well-by-well performances by calibration of local cell properties. The inclusion of multiscale calibration, integrating production data in coarse grid and successively finer grids sequentially, is critical for history matching high-resolution geologic models through significant reduction in simulation time.
For rate optimization, we develop a hierarchical analytical method using streamline-assisted flood efficiency maps. The proposed approach avoids use of complex optimization tools; rather we emphasize the visual and the intuitive appeal of streamline method and utilize analytic solutions derived from relationship between streamline time of flight and flow rates. The proposed approach is analytic, easy to implement and well-suited for large-scale field applications.
Finally, we present a hierarchical Pareto-based approach to history matching under conflicting information. In this work we focus on multiobjective optimization problem, particularly conflicting multiple objectives during history matching of reservoir performances. We incorporate Pareto-based multiobjective evolutionary algorithm and Grid Connectivity-based Transformation (GCT) to account for history matching with conflicting information.
The power and effectiveness of our approaches have been demonstrated using both synthetic and real field cases.
48
Lin, I.-chi, and 林沂錡. "A research on the matching rate of foreign health caring labors - take K international labor agency for example." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/85348191955726310630.
Анотація:
碩士國立中山大學
高階經營碩士班
100
According to the lower birth rate and more mature demographic structure, our society is facing the problem about aging of population. The market need for long term care is getting more and more obvious in recent years, and especially the atmosphere to hire the foreign care assistant is quite common and widely-spread in Taiwan. Also by viewing the statistic survey, it is pretty obvious to know that the number about foreign worker who were imported into Taiwan is increasing year by year in a quite significant way. However the processes and paper work are with great complicated, so most of the people who have the demand of foreign care assistant will tend to apply through the international humanity agency. Then the original motive of our research is from the prospect of the agency to elevate its value of their service. Therefore at the very beginning we will focus on the related factors which influence the rate of match, and then we will go deeper to explore the more specific cause which has the relevant connection with the foreign workers’ job satisfaction. In addition, we conclude that there were two significant dimensions which might influence the job satisfaction, and then they are the relationship between employer and employee, and the other dimension is about the qualification of the workers to meet the requirement and the characteristic of caring job. This thesis will utilize some questionnaires which include: performance, job satisfaction, leader-member exchange relationship, empathy, hardness and social personality. This Research used the foreign health care assistants working in Taiwan from Indonesia as samples to do the actual research. We gave out 100 questionnaires in total, and collected 93 effective. And we used SPSS statistic software to analyses the relation between every parameter.The result of study is found as follows: 1. The match rate will be demonstrated by the performance which received by the employer. 2. The Job satisfaction will influence the performance as care assistants. 3. The Job satisfaction will be influenced by the leader-member exchange relationship, empathy and social personality tendency.
49
Lyons, Laura. "The Effects of the Mastery of Auditory Matching of Component Sounds to Words on the Rate and Accuracy of Textual and Spelling Responses." Thesis, 2014. https://doi.org/10.7916/D8542KRM.
Анотація:
Textual responding or a see print and say sound response, often called "decoding," is a key component of reading. Teaching letter sounds and how to say these sounds together as words is a repertoire that allows students to become independent readers (McGuiness, 2004). However, some students have difficulty with blending letter sounds to read words (Carnine, 1997). Spelling is the reciprocal process to textual responding (McGuiness, 2004). To spell, an individual must segment component sounds in a word to write the correct graphemes.
In two experiments, the experimenter tested the effects of the acquisition of matching component phoneme sounds to the words they comprise and vise-versa using an experimenter designed computer-based auditory match to sample (MTS) instructional program on textual responding and spelling of words with taught phonemes, and the rate of acquisition of new textual responses. Participants in Experiment I included 6 kindergarten students and 3 preschool students who required many instructional trials to meet textual responding objectives. Participants in Experiment II were 2 students (one kindergartener and one second grader) diagnosed with autism and 3 kindergarten students. Participants did not read words composed of letter sounds they had mastered. Results of Experiments I and II demonstrated a functional relation between the auditory matching program and textual responding and rates of learning for all participants. Results are discussed from the perspective of the Verbal Behavior Developmental Theory (VBDT), in terms of the importance of verbal developmental cusps and the joining of listener and speaker repertoires in textual responding and spelling.
50
Lee, Heung Ki. "Adaptive Resource Management Schemes for Web Services." 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7608.
Анотація:
Web cluster systems provide cost-effective solutions when scalable and reliable
web services are required. However, as the number of servers in web cluster systems
increase, web cluster systems incur long and unpredictable delays to manage servers.
This study presents the efficient management schemes for web cluster systems.
First of all, we propose an efficient request distribution scheme in web cluster
systems. Distributor-based systems forward user requests to a balanced set of waiting
servers in complete transparency to the users. The policy employed in forwarding
requests from the frontend distributor to the backend servers plays an important
role in the overall system performance. In this study, we present a proactive request
distribution (ProRD) to provide an intelligent distribution at the distributor.
Second, we propose the heuristic memory management schemes through a web
prefetching scheme. For this study, we design a Double Prediction-by-Partial-Match
Scheme (DPS) that can be adapted to the modern web frameworks. In addition, we
present an Adaptive Rate Controller (ARC) to determine the prefetch rate depending
on the memory status dynamically. For evaluating the prefetch gain in a server node,
we implement an Apache module.
Lastly, we design an adaptive web streaming system in wireless networks. The
rapid growth of new wireless and mobile devices accessing the internet has contributed
to a whole new level of heterogeneity in web streaming systems. Particularly, in-home
networks have also increased in heterogeneity by using various devices such as laptops, cell phone and PDAs. In our study, a set-top box(STB) is the access pointer between
the internet and a home network. We design an ActiveSTB which has a capability of
buffering and quality adaptation based on the estimation for the available bandwidth
in the wireless LAN.