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Jämförelse mellan Theory of Mind-förmåga och pragmatisk förmåga hos svenska barn i 4 och 5 års ålderKarlsson, Elinor, Östling, Linnéa January 2012 (has links)
Theory of mind involves the ability to take another person’s perspective in thought, emotions and intentions. There is today a lack of instruments to assess children’s development of Theory of Mind (ToM) in Swedish. ToM is considered by many scientists to be the basis for development of pragmatic competence. The relationship between these two abilities is complex and not fully resolved. Both abilities are important components for the development of social skills. The purpose of this study was to compare 4 and 5-year olds ToM-ability measured with a Swedish version of Wellman and Liu’s ToM-scale, Sally Anne and Social Emotional Test with estimated pragmatic competence measured with the Children’s Communication Checklist (CCC). To make this possible the study also aims to translate and evaluate a Swedish version of Wellman and Liu’s ToM-scale. In the study 39 children in the age of 4 and 5 years old participated (20 4-year olds and 19 5-year olds). The present study can point to the relationship between the ToM1 ability false belief and pragmatic abilities, as well as different abilities related to pragmatics (conversational rapport, use of discourse context and prosody). Correlation between prosody and other measures of ToM1 abilities was also observed. The result can be linked to previous research on the relationship between pragmatics and ToM. ToM and pragmatic are two abilities that are linked to each other. But as the result is not entirely conclusive, they may also shed more light to the complexity of these abilities and their relationship. The result of the evaluation of Wellman and Liu’s ToM-scale shows that most of the children got a result pattern that agreed with the hypothesis of a gradual acquisition of ToM-abilties. However, Swedish 4 year olds did to a greater extent passed questions in a pattern that was not compatible with the gradual acquisition claim than American children did in a previous study. One reason for this result may be cultural differences. More research is needed on a larger selection of subjects and a wider range of age groups before any conclusions can be drawn. However, the translated scale can be used in a qualitative way, to examine which aspects of a ToM a child comprehends.
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A game theoretic analysis of adaptive radar jammingBachmann, Darren John Unknown Date (has links) (PDF)
Advances in digital signal processing (DSP) and computing technology have resulted in the emergence of increasingly adaptive radar systems. It is clear that the Electronic Attack (EA), or jamming, of such radar systems is expected to become a more difficult task. The reason for this research was to address the issue of jamming adaptive radar systems. This required consideration of adaptive jamming systems and the development of a methodology for outlining the features of such a system is proposed as the key contribution of this thesis. For the first time, game-based optimization methods have been applied to a maritime counter-surveillance/counter-targeting scenario involving conventional, as well as so-called ‘smart’ noise jamming.Conventional noise jamming methods feature prominently in the origins of radar electronic warfare, and are still widely implemented. They have been well studied, and are important for comparisons with coherent jamming techniques.Moreover, noise jamming is more readily applied with limited information support and is therefore germane to the problem of jamming adaptive radars; during theearly stages when the jammer tries to learn about the radar’s parameters and its own optimal actions.A radar and a jammer were considered as informed opponents ‘playing’ in a non-cooperative two-player, zero-sum game. The effects of jamming on the target detection performance of a radar using Constant False Alarm Rate (CFAR)processing were analyzed using a game theoretic approach for three cases: (1) Ungated Range Noise (URN), (2) Range-Gated Noise (RGN) and (3) False-Target (FT) jamming.Assuming a Swerling type II target in the presence of Rayleigh-distributed clutter, utility functions were described for Cell-Averaging (CA) and Order Statistic (OS) CFAR processors and the three cases of jamming. The analyses included optimizations of these utility functions, subject to certain constraints, with respectto control variables (strategies) in the jammer, such as jammer power and spatial extent of jamming, and control variables in the radar, such as threshold parameter and reference window size. The utility functions were evaluated over the players’ strategy sets and the resulting matrix-form games were solved for the optimal or ‘best response’ strategies of both the jammer and the radar.
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Módulos neurais para modelagem de falsas memórias / Neural modules for false memories modellingRenato Ferrari Pacheco 08 April 2004 (has links)
As falsas memórias são um tipo falha de memória, em que o indivíduo pode (a) reconhecer como tendo visto antes um objeto ou evento que não tenha ocorrido ou (b) não reconhecer algo previamente presenciado. Estes são o falso reconhecimento e a rejeição errada. Segundo a teoria do rastro difuso, dois processos distintos agem em paralelo durante a memorização e reconhecimento, um sobre as informações literais (verbatim) e o outro sobre a essência do significado da palavra (gist). Neste trabalho é proposto um sistema modular de redes neurais artificiais que considera estes dois processos, características funcionais das estruturas cerebrais envolvidas na memorização e fluxo de informação análogo ao ocorrido no cérebro. O modelo neural é validado através de treinamento para armazenar e recuperar listas de palavras semanticamente relacionadas. Na formulação do modelo e da representação foram considerados a representação fonológica e significado das palavras, de forma a simular as computações ocorridas e os resultados obtidos em experimentos efetuados com sujeitos humanos. Nestes experimentos, 12 listas de aproximadamente 15 palavras, cada lista semanticamente relacionadas a um tema são ouvidas e, em seguida, algumas destas palavras, a palavra tema e outras palavras não relacionadas são também ouvidas e os indivíduos respondem se cada palavra fora ouvida previamente. Os resultados obtidos computacionalmente aproximam-se bastante dos resultados obtidos com sujeitos humanos, e o modelo produzido serve como base para estudo das influências dos diversos processos atuantes durante a memorização e reconhecimento. / False memories are a kind of memory failure, in which the subject may (a) recognize as known an never seen object or never happened fact or (b) don\'t recognize something that was already presented him. These are false memories and wrong rejections. According to false memory theory, two parallel processes act during memorization and recognition, one on verbatim information and other on gist information. In this work is proposed a artificial neural network model system that takes in account these two processes, functional issues about brain structures involved on memorization and the an information flow analog to the occurred in the brain. The neural model is validated by training to store in recover lists of semantically related words. In the model and representation scheme formulation, phonological and semantic informations were used intending to simulate brain computations and results of human subjects experiments. In such experiment, 12 lists of something about 15 semantically related words, are heard and, in the second step, in the sequence, many of these words, other related words and not related words are heard in a recognition test, when subjets say if that word was or was not heard during memorization steps. Results obtained from computer tests are very close of human results, and the produced model may be used as a tool for analysis of the influences of the many processes that take place during memorization and recognition.
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Conception de faux substrats fluorescents (FFS) dans le cadre de l’étude du transporteur vésiculaire de nucléotides et de la Sialine / Design of fluorescent false substrates (FFS) to study vesicular nucleotide transporter and SialinDubois, Lilian 15 November 2013 (has links)
Le concept de composés appelés FFS, pour faux substrats fluorescents (ou FFN pour les neurotransmetteurs), a été introduit par le groupe du Dr Sames qui a conçu et optimisé des molécules fluorescentes reconnues comme substrats par le Transporteur Vésiculaire de Monoamine (VMAT2). Ces composés, une fois accumulés dans des vésicules synaptiques, ont permis la visualisation de l’activité neuronale monoaminergique en temps réel. Ce concept a servi d’hypothèse pour ce travail de thèse. En effet, nous avons conçu, synthétisé et évalué la potentialité de deux familles chimiques comme substrats fluorescents de transporteurs de la famille SLC17 : VNUT (transporteur vésiculaire de nucléotides) et la Sialine (transporteur d’acide sialique). Les molécules fluorescentes synthétisées devront être capables de remplacer/mimer les substrats naturels de VNUT et de la Sialine (respectivement l’ATP et le Neu-5-Ac) et de couvrir une large gamme de longueurs d’ondes d’émission pour nous adapter aux problématiques biologiques. L’élaboration de tels composés a été effectuée par conception rationnelle en synergie avec les résultats des tests d’inhibition et de transport et à partir de touches issues du criblage virtuel. Deux composés ont été plus particulièrement étudiés. D’une part, l’ATP a été modifiée en remplaçant le motif adénine par un fluorophore (éthéno, coumarines, quinoléines…). D’autre part, une touche virtuelle (Fmoc-Lys(Cbz)-OH) issue d’un vHTS sur la Sialine a été sélectionnée pour sa structure facilement modifiable, qui a permis l’incorporation aisée de motifs fluorescents. Une cinquantaine de composés a donc été synthétisée et évaluée pour leur capacité d’inhibition ou de substrat sur les cibles sélectionnées. Les résultats prometteurs de plusieurs composés en tant qu’inhibiteur laissent de nombreuses perspectives pour la compréhension de la machinerie vésiculaire. / The concept of compounds called FFSs for false fluorescent substrates (or FFNs for neurotransmitters) was introduced by the group of Dr Sames who designed and optimized fluorescent molecules recognized as substrates by the Vesicular Monoamine Transporter (VMAT2). Once accumulated in synaptic vesicules, these compounds have allowed visualization of the monoaminergic neuronal activity in real time. This concept has been used as hypothesis for this thesis work. Indeed, we have designed, synthesized and evaluated the potential of two chemical families as fluorescent substrates of SLC17 transporter family: VNUT (Vesicular Nucleotide Transporter) and Sialin (sialic acid transporter). The synthesized fluorescent molecules must be able to replace/mimic the natural substrates of VNUT and Sialin ( ATP and Neu-5-Ac, respectively) and to cover a wide range of emission wavelengths to deal with biological problems. The development of such compounds was performed by rational design in synergy with the results of inhibition and transport tests and by virtual screening. Two compounds have been specifically studied. On one hand, ATP was modified by replacing the adenine pattern by a fluorophore (etheno, coumarins, quinolines…). On the other hand, a virtual hit (Fmoc-Lys(Cbz)-OH), derived from vHTS targeted to Sialin, was selected for the ease to incorporate fluorescent patterns. Therefore, fifty compounds were synthesized and evaluated for their inhibitory or substrate ability on selected targets. The promising results of several compounds as inhibitors give rise to perspectives for understanding vesicular machinery.
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Bayesian Methods Under Unknown Prior Distributions with Applications to The Analysis of Gene Expression DataRahal, Abbas 14 July 2021 (has links)
The local false discovery rate (LFDR) is one of many existing statistical methods that analyze multiple hypothesis testing. As a Bayesian quantity, the LFDR is based on the prior probability of the null hypothesis and a mixture distribution of null and non-null hypothesis. In practice, the LFDR is unknown and needs to be estimated. The empirical Bayes approach can be used to estimate that mixture distribution.
Empirical Bayes does not require complete information about the prior and hyper prior distributions as in hierarchical Bayes. When we do not have enough information at the prior level, and instead of placing a distribution at the hyper prior level in the hierarchical Bayes model, empirical Bayes estimates the prior parameters using the data via, often, the marginal distribution.
In this research, we developed new Bayesian methods under unknown prior distribution. A set of adequate prior distributions maybe defined using Bayesian model checking by setting a threshold on the posterior predictive p-value, prior predictive p-value, calibrated p-value, Bayes factor, or integrated likelihood. We derive a set of adequate posterior distributions from that set. In order to obtain a single posterior distribution instead of a set of adequate posterior distributions, we used a blended distribution, which minimizes the relative entropy of a set of adequate prior (or posterior) distributions to a "benchmark" prior (or posterior) distribution. We present two approaches to generate a blended posterior distribution, namely, updating-before-blending and blending-before-updating. The blended posterior distribution can be used to estimate the LFDR by considering the nonlocal false discovery rate as a benchmark and the different LFDR estimators as an adequate set.
The likelihood ratio can often be misleading in multiple testing, unless it is supplemented by adjusted p-values or posterior probabilities based on sufficiently strong prior distributions. In case of unknown prior distributions, they can be estimated by empirical Bayes methods or blended distributions. We propose a general framework for applying the laws of likelihood to problems involving multiple hypotheses by bringing together multiple statistical models.
We have applied the proposed framework to data sets from genomics, COVID-19 and other data.
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A performance measurement of a Speaker Verification system based on a variance in data collection for Gaussian Mixture Model and Universal Background ModelBekli, Zeid, Ouda, William January 2018 (has links)
Voice recognition has become a more focused and researched field in the last century,and new techniques to identify speech has been introduced. A part of voice recognition isspeaker verification which is divided into Front-end and Back-end. The first componentis the front-end or feature extraction where techniques such as Mel-Frequency CepstrumCoefficients (MFCC) is used to extract the speaker specific features of a speech signal,MFCC is mostly used because it is based on the known variations of the humans ear’scritical frequency bandwidth. The second component is the back-end and handles thespeaker modeling. The back-end is based on the Gaussian Mixture Model (GMM) andGaussian Mixture Model-Universal Background Model (GMM-UBM) methods forenrollment and verification of the specific speaker. In addition, normalization techniquessuch as Cepstral Means Subtraction (CMS) and feature warping is also used forrobustness against noise and distortion. In this paper, we are going to build a speakerverification system and experiment with a variance in the amount of training data for thetrue speaker model, and to evaluate the system performance. And further investigate thearea of security in a speaker verification system then two methods are compared (GMMand GMM-UBM) to experiment on which is more secure depending on the amount oftraining data available.This research will therefore give a contribution to how much data is really necessary fora secure system where the False Positive is as close to zero as possible, how will theamount of training data affect the False Negative (FN), and how does this differ betweenGMM and GMM-UBM.The result shows that an increase in speaker specific training data will increase theperformance of the system. However, too much training data has been proven to beunnecessary because the performance of the system will eventually reach its highest point and in this case it was around 48 min of data, and the results also show that the GMMUBM model containing 48- to 60 minutes outperformed the GMM models.
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UHF-SAR and LIDAR Complementary Sensor Fusion for Unexploded Buried Munitions DetectionDepoy, Randy S., Jr. January 2012 (has links)
No description available.
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Morphology and taxonomy of tortricid moth pests attacking fruit crops in South AfricaRentel, Monique 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Cydia pomonella (codling moth), Thaumatotibia leucotreta (False codling moth), Thaumatotibia
batrachopa (Macadamia nut borer), Grapholita molesta (Oriental fruit moth), Cryptophlebia peltastica
(Litchi moth), Epichoristodes acerbella (Pear leafroller/Carnation worm) and Lozotaenia capensana (Apple
leafroller) are the most economically important tortricids affecting various crops in South Africa. The
correct identification of these species, especially of the larval stage, is of great importance in pest
management. Using available literature, augmented by additional morphological studies, an interactive
identification key (Lucid key) for larval and adult stages of the seven species was developed. The colour
and markings of the head, characteristics of the prothoracic and anal shields, the position of the
prespiracular setae (L-group) relative to the spiracle on the prothoracic segment, the position of the spiracle
on the eighth abdominal segment and L-group on the ninth abdominal segment, as well as the presence or
absence of the anal comb are key characteristics for larval identification. For adult identification, wing
pattern and genitalia are the most important features. However, the use of genitalia for moth identification
might be difficult for the lay user, as the dissection and mounting of these structures requires certain skills
and specialized equipment. Thus, genitalia have not been included in the Lucid Key. Differences in the
morphological characteristics of most pupae were so minute that this stage was also not included in the
Lucid key. However, the pupae of E. acerbella and L. capensana are easily distinguished from those of the
other species by the presence of acremaster. This study also included the first morphological description of
the pupa of L. capensana, which can be distinguished from that of E. acerbella by various features of the
cremaster, antennae, spiracle shape, number of setae on abdominal segments A5-7, the size of spines on
A3-7, and the presence/absence of spines on A9. A previous study by Timm (2005) indicated that
geographically isolated populations of T. leucotreta tend to be genetically distinct. This raised the question
of whether speciation/subspeciation has occurred or is occurring. Male moth genitalia are thought to evolve
rapidly and are often the only features that can reliably distinguish similar species. Hence, variation in the
shape of the valvae of T. leucotreta was used to determine whether divergence has occurred between
populations of T. leucotreta. Elliptical Fourier analysis was used to analyze the valvar variation in three
different populations. Although some variation in valvar shape was detected among mean population values
for certain traits, no clear pattern emerged. Principle component analysis also showed no distinct clustering
of valvae shape among populations, providing no evidence for divergence in male genitalia and therefore
no morphological evidence of incipient speciation. / AFRIKAANSE OPSOMMING: Cydia pomonella (Kodlingmot), Thaumatotibia leucotreta (Valskodlingmot), T. batrachopa
(Makadamianeutboorder), Grapholita molesta (Oosterse vrugtemot), Cryptophlebia peltastica
(Lietsjiemot), Epichoristodes acerbella (Peerbladroller/Angelierrusper) en Lozotaenia capensana
(Appelbladroller) is die mees ekonomies belangrike tortrisiede van die vrugtebedryf in Suid-Afrika. Die
juiste identifikasie van hierdie spesies, veral van hulle larwale stadium, is van groot belang by plaagbestuur.
Deur gebruik te maak van beskikbare literatuur, aangevul deur bykomstige morfologiese studies, is ‗n
interaktiewe uitkenningssleutel (―Lucid key‖) vir die larwale en volwasse stadia van die sewe spesies
ontwikkel. Die kleur en tekening van die kop, kenmerke van die prothorakale en anale skild, die ligging
van die prespirakulêre setae (L-groep) relatief tot die spiraculum op die prothorakale segment, die ligging
van die spirakulum op die agste abdominale segment en L-groep op die negende abdominale segment,
asook die aan- of afwesigheid van die anale kam is sleutel kenmerke vir larwale uitkenning. Vir die
volwassenes is die vlerktekening en genitalia die mees belangrike kenmerke. Die gebruik van die genitalia
vir motuitkenning kan egter vir die leek gebruiker moeilik wees omdat die disseksie en montering van
hierdie strukture bepaalde vaardighede en gespesialiseerde toerusting vereis. Vir die rede is die genitalia
nie in die Lucid-sleutel ingesluit nie. Verskille in die morfologiese kenmerke van meeste papies is klein en
die stadium is gevolglik ook nie in die sleutel ingesluit nie. Die papies van E. acerbella en L. capensana
kan egter maklik van die ander spesies onderskei word deur die aanwesigheid van ‗n cremaster. Hierdie
studie sluit ook die eerste morfologiese beskrywing van die papie van L. capensana in, wat van dié van E.
acerbella onderskei kan word deur gebruik te maak van kenmerke van die cremaster, antennae, spirakulêre
vorm, aantal setae op abdominale segmente A5-7, die grootte van stekels op A3-7, en die aan- of
afwesigheid van stekels op A9. ‗n Vroeëre studie (Timm 2005) het aangedui dat geografies geïsoleerde
bevolkings van T. leucotreta neig om geneties verskillend te wees. Dit het die vraag laat ontstaan of
spesiasie/subspesiasie moontlik plaasgevind het of steeds plaasvind. Manlike mot genitalië word geag om
vinnig te ontwikkel en is dikwels die enigste kenmerke wat betroubaar tussen soortgelyke spesies kan
onderskei. Dus is die variasie in die vorm van die valvae van T. leucotreta gebruik om te bepaal of
divergensie wel tussen bevolkings van T. leucotreta plaasgevind het. Elliptiese Fourier ontleding is gebruik
om die valvae se variasie by drie verskillende bevolkings te ontleed. Alhoewel enkele variasie in die vorm
van die valvae bespeur is by die gemiddelde bevolkingswaardes vir bepaalde eienskappe, kon geen
duidelike patroon bespeur word nie. Hoofkomponentontleding het ook geen duidelike groepering van
valvae se vorm tussen bevolkings getoon nie, wat geen bewys lewer van divergensie in die manlike
genitalia en dus geen morfologiese bewys van beginnende spesiasie.
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Latewood Chronology Development For Summer-Moisture Reconstruction In The US SouthwestGriffin, Daniel, Meko, David M., Touchan, Ramzi, Leavitt, Steven W., Woodhouse, Connie A. 07 1900 (has links)
Tree-ring studies have demonstrated that conifer latewood measurements contain information
on long-term North American monsoon (NAM) variability, a hydroclimatic feature of great
importance to plants, animals, and human society in the US Southwest. This paper explores data-treatment options for developing latewood chronologies aimed at NAM reconstruction. Archived wood samples for five Douglas-fir (Pseudotsuga menziesii, Mirb. Franco) sites in southeastern Arizona are augmented with new collections. The combined dataset is analyzed along with time series of regionally averaged observed precipitation to quantify the strength of regional precipitation signal in latewood time series and to identify ways of increasing the signal strength. Analysis addresses the signal strength influences of including or excluding ‘‘false’’ latewood bands in the nominal ‘‘latewood’’ portion of the ring, the necessary adjustment of latewood width for statistical dependence on antecedent earlywood width, and tree age. Results suggest that adjusted latewood width chronologies from individual sites can explain around 30% of the variance of regional summer (July–August) precipitation—increasing to more than 50% with use of multiple chronologies. This assessment is fairly insensitive to the treatment of false latewood bands (in intra-annual width and 𝛿¹³C variables), and to whether latewood-width is adjusted for dependence on earlywood-width at the core or site level. Considerations for operational chronology development in future studies are (1) large tree-to-tree differences in moisture signal, (2) occasional nonlinearity in EW-LW dependence, and (3) extremely narrow and invariant latewood width in outer portions of some cores. A protocol for chronology development addressing these considerations is suggested.
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The influence of deceptive advertising on customer trust and loyalty : A Study of Telecom Sector in PakistanShahzad, Mirza Khuram, Kausar, Mehnaz January 2016 (has links)
Purpose: The effects of deceptive advertising practices on customer loyalty towards mobileservice providers have been investigated empirically by this study. The main contribution ofthis study is to investigate the perceived deception-customer loyalty relationship under themoderating effect of corporate image and mediating effect of customer trust. The study is done in the context of Pakistan’s telecommunication sector.Existing literature is insufficient to explain perceived deception and customer loyalty relationship. We proposed a model to test and explain the interrelationship of deception,trust, loyalty and corporate image. Research Methodology: we have adopted quantitative research method, according to needof our study. A total sample of 232 respondents has been achieved with the help of selfadministeredquestionnaire. Measurement scale for perceived deception were taken fromChaouachi & Rached (2012) and for corporate image, customer trust and customer loyaltyhave been found from Aydin & Özer (2005). Analysis & Findings: Descriptive and inferential statistical tools were used for analysis.Correlation analysis, simple and multiple regression analysis were conducted under theinferential statistical part. The findings have rejected the proposed hypothesis that perceiveddeception is negatively associated with customer trust and loyalty. We found customer trustas a mediator between perceived deception and customer loyalty while corporate imagemoderates the relationship between perceived deception and customer trust. Research Limitations: the study could not achieve highly representative sample of overallpopulation as Facebook was selected to conduct survey due to time constraint. Implications and future research: The study shows that deception in advertising perceivedby customer does not affect trust and loyalty in a negative way which suggests that there areadditional factor that can explain the relationship further. A comparative study withqualitative focus could be revealing in this context.
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