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Dissertations / Theses on the topic 'Signal behavior'

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Published: 10 December 2022
Last updated: 28 January 2023

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1

Elmitiny, Noor. "Providing a Better Understanding for the Motorist Behavior Towards Signal Change." Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4264.

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This research explores the red light running phenomena and offer a better understanding of the factors associated with it. The red light running is a type of traffic violation that can lead to angle crash and the most common counter measure is installing a red light running cameras. Red light running cameras some time can reduce the rates of red light running but because of the increased worry of the public towards crossing the intersection it can cause an increase in rear end crashes. Also the public opinion of the red light running cameras is that they are a revenue generator for the local counties and not a concern of public safety. Further more, they consider this type of enforcement as violation of privacy. There was two ways to collect the data needed for the research. One way is through a tripod cameras setup temporarily placed at the intersection. This setup can collect individual vehicles caught in the change phase with specific information about their reactions and conditions. This required extensive manual analysis for the recorded videos plus data could not be collected during adverse weather conditions. The second way was using traffic monitoring cameras permanently located at the site to collect red light running information and the simultaneous traffic conditions. This system offered more extensive information since the cameras monitor the traffic 24/7 collecting data directly. On the other hand this system lacked the ability to identify the circumstances associated with individual red light running incidents. The research team finally decided to use the two methods to study the red light running phenomena aiming to combine the benefits of the two systems. During the research the team conducted an experiment to test a red light running countermeasure in the field and evaluate the public reaction and usage of this countermeasure. The marking was previously tested in a driving simulator and proved to be successful in helping the drivers make better stop/go decisions thus reducing red light running rates without increasing the rear-end crashes. The experiment was divided into three phases; before marking installation called "before", after marking installation called "after", and following a media campaign designed to inform the public about the use of the marking the third phase called "after media" The behavior study that aimed at analyzing the motorist reactions toward the signal change interval identified factors which contributed to red light running. There important factors were: distance from the stop bar, speed of traffic, leading or following in the traffic, vehicle type. It was found that a driver is more likely to run red light following another vehicle in the intersection. Also the speeding vehicles can clear the intersection faster thus got less involved in red light running violations. The proposed "Signal Ahead" marking was found to have a very good potential as a red light running counter measure. The red light running rates in the test intersection dropped from 53 RLR/hr/1000veh for the "before" phase, to 24 RLR/hr/1000veh for the "after media" phase. The marking after media analysis period found that the marking can help the driver make stop/go decision as the dilemma zone decreased by 50 ft between the "before" and the "after media" periods. Analysis of the traffic condition associated with the red light running it revealed that relation between the traffic conditions and the red light running is non-linear, with some interactions between factors. The most important factors included in the model were: traffic volume, average speed of traffic, the percentage of green time, the percentage of heavy vehicles, the interaction between traffic volume and percentage of heavy vehicles. The most interesting finding was the interaction between the volume and the percent of heavy vehicles. As the volume increased the effect of the heavy vehicles reversed from reducing the red light running to increasing the red light. This finding may be attributed to the sight blocking that happens when a driver of a passenger car follows a larger heavy vehicle, and can be also explained by the potential frustration experienced by the motorist resulting from driving behind a bigger vehicle.
Ph.D.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering PhD
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2

Jai, Wun Hoa Arthur. "Underwater acoustic signal behavior prediction in the region of Kauai Island." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/33582.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
Includes bibliographical references (p. 175-176).
Behavior of underwater sound propagation over long-ranges has been studied for several decades. The purpose of this is to describe sound propagation phenomena in various ocean environments. The key to understanding and visualizing is mathematical modeling. In the ocean acoustics community, four major mathematical techniques have been commonly used to model behavior of acoustic signal in the ocean environment. And they can be categorized into two different fields, range-independent and range-dependent. The accuracy of each method is depends on the environment characteristics. Since the propagating signal can be characterized through the mathematical modeling, it is then possible to use the propagating signal to perform beamforming and determine the characteristic of beam output.
by Wun Hoa Arthur Jai.
S.M.
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3

Glaser, John Stanley 1964. "Topics in large-signal behavior of power electronic converters and systems." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/282217.

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A variety of topics in large-signal and system-level power electronics are explored. First, the load-sharing problem for converters with parallel- and series-connected outputs is defined and explained. Requirements for load-sharing behavior are illustrated graphically. Many classes of switching converters are capable of load-sharing aside from current-programmed-mode (CPM) converters, including but not limited to discontinuous-mode (DCM) pulse-width-modulated (PWM) converters and resonant converters. The input filter problem is studied for high-power-factor rectifiers (HPFRs) based on the DCM flyback converter. Such HPFRs require an input filter to reduce switching noise conducted to the AC line, but the filter can degrade the power factor and interfere with converter operation. The analysis allows filter design that minimizes and balances these effects. Intuitive and analytical approaches are given and compared. The analytical approach uses phase plane methods usually used for resonant converter analysis. Although the filter design is for a specific converter, the approach is applicable to any HPFR. A single-quadrant negative resistor is synthesized from a DCM flyback converter. This circuit is simple, efficient, and can handle power levels over 100W. A design procedure and small-signal analysis are given. Additionally, a set of large-signal dynamic circuit models are presented for DCM PWM converters. A general impedance synthesizer is developed based on a four-quadrant switching converter. This circuit is used to create the negative resistance pseudoinverter, which puts power onto the AC line for sale to a utility. To develop the pseudoinverter, the concept of load reduction is employed. Potential stability problems are studied and a solution implemented. The synthesis of self-contained reactive components is also studied. Extensive experimental verification substantiates the majority of the concepts in this dissertation. Simulation is also used to support some of the analysis.
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4

Phillips, Catherine T. Johnston Carol Eileen. "Evolution of signal divergence and behavior in Cyprinella galactura, the whitetail shiner." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Fall/Dissertations/PHILLIPS_CATHERINE_27.pdf.

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5

Al-Mudhaffar, Azhar. "Impacts of Traffic Signal Control Strategies." Doctoral thesis, Stockholm : Division of transports and logistics, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4268.

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6

Drake, Daniel F. "Information's role in the estimation of chaotic signals." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/14793.

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7

McKay, Ailsa J. "Central vasopressin signalling and aggressive behaviour." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/4194.

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Although many signalling molecules appear relevant to the production of complex behaviours, those that are important to the physiological regulation of behaviour, and so those that characterise individual styles of behaviour, are unknown. Vasopressin is the strongest candidate regulator of social behaviour. Experiments were carried out in consideration that vasopressin may directly regulate aggressive behaviour in lactating rats. Patterns of immediate early gene expression during/subsequent to aggressive behaviour suggested specific neural circuits may have significant direct regulatory influence over particular behaviours, and that activation of the V1b vasopressin receptor, in these circuits, may contribute to this putative regulatory signalling. In situ hybridisation studies indicated that patterns of vasopressin release, rather than receptor expression, might be important for any peripartum changes in behaviour driven by vasopressin. Although their relative importance is unknown, central actions of vasopressin may exert a strong regulatory influence over a range of behaviours, across a range of species.
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8

Saggese, Alessia. "Detecting and indexing moving objects for behavior analysis by video and audio interpretation." Doctoral thesis, Caen, 2014. http://www.theses.fr/2014CAEN2021.

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Dans les dernières décennies, nous avons été témoin d'un besoin grandissant de sécurité dans les espaces publics. La limitation principale induite par les systèmes de vidéo surveillance réside dans la surcharge cognitive des opérateurs humains chargés de la sécurité, ce qui diminue leur capacités à analyser le flux d'information émanant de sources multimédia multiples. Pour ces raisons, nous proposons dans cette thèse un système de surveillance intelligent capable d'associer des images et des vidéos à une interprétation sémantique afin de faire le lien entre des représentations bas niveau, sous forme de pixels, et le haut niveau correspondant à une description en langage naturel qu'un être humain pourrait faire d'une scène. Plus précisément, les travaux proposés débutent par l'analyse des vidéos et par l'extraction des trajectoires des objets présents dans la scène. Une fois extraites, ce grand nombre de trajectoires doit être indexé et stocké afin d'augmenter la performance du système durant la phase de reconnaissance. En outre, l'opérateur humain est informé immédiatement si un comportement anormal est observé. Tandis que l'information extraite des vidéos n'est pas suffisante ou n'est pas suffisamment fiable, le système proposé est enrichi par un module en charge de la reconnaissance des événements sonores tels que des tirs, des cris ou des vitres cassées. Chaque module proposé a été à la fois testé sur des jeux de données standards mais aussi dans un environnement réel ; les résultats obtenus, tout comme l'application des méthodes proposées dans un contexte réel, permettent de confirmer la contribution de nos travaux à l'état de l'art
In the last decades we have assisted to a growing need for security in many public environments. The main limitation of this traditional audio-video surveillance systems lies in the so called psychological overcharge issue of the human operators responsible for security, that causes a decrease in their capabilities to analyse raw data flows from multiple sources of multimedia information. For the above mentioned reasons, in this thesis we propose an intelligent surveillance system able to provide images and video with a semantic interpretation, for trying to bridge the gap between their low-level representation in terms of pixels, and the high-level, natural language description that a human would give about them. In particular, the proposed framework starts by analysing the videos and by extracting the trajectories of the objects populating the scene. Once extracted, this large amount of trajectories needs to be indexed and properly stored in order to improve the overall performance of the system during the retrieving. Furthermore, the human operator is informed as soon as an abnormal behaviour occurs. Whereas the information extracted from the videos are not sufficient or not sufficiently reliable, the proposed system in enriched by a module in charge of recognizing audio events, such as shoots, screams or broken glasses. Each proposed module has been tested both over standard datasets and in real environments; the promising obtained results confirm the advance with respect to the state of the art, as well as the applicability of the proposed method in real scenarios
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9

Lee, Chungyong. "Noise reduction methods for chaotic signals with application to secure communications." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/14823.

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10

Larsson, Petter. "Automatic Visual Behavior Analysis." Thesis, Linköping University, Department of Electrical Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1980.

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This work explores the possibilities of robust, noise adaptive and automatic segmentation of driver eye movements into comparable quantities as defined in the ISO 15007 and SAE J2396 standards for in-vehicle visual demand measurements. Driver eye movements have many potential applications, from the detection of driver distraction, drowsiness and mental workload, to the optimization of in-vehicle HMIs. This work focuses on SeeingMachines head and eye-tracking system SleepyHead (or FaceLAB), but is applicable to data from other similar eye-tracking systems. A robust and noise adaptive hybrid algorithm, based on two different change detection protocols and facts about eye-physiology, has been developed. The algorithm has been validated against data, video transcribed according to the ISO/SAE standards. This approach was highly successful, revealing correlations in the region of 0.999 between analysis types i.e. video transcription and the analysis developed in this work. Also, a real-time segmentation algorithm, with a unique initialization fefature, has been developed and validated based on the same approach.

This work enables real-time in-vehicle systems, based on driver eye-movements, to be developed and tested in real driving conditions. Furthermore, it has augmented FaceLAB by providing a tool that can easily be used when analysis of eye movements are of interest e.g. HMI and ergonomics studies, analysis of warnings, driver workload estimation etc.

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11

Laporte, Marion N. C. "Pant-grunts in wild chimpanzees (Pan troglodytes schweinfurthii) : the vocal development of a social signal." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/1973.

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While the gestural communication of apes is widely recognised as intentional and flexible, their vocal communication still remains considered as mostly genetically determined and emotionally bound. Trying to limit the direct projections of linguistic concepts, that are far from holding a unified view on what constitute human language, this thesis presents a detailed description of the pant-grunt vocalisation usage and development in the chimpanzees (Pan troglodytes schweinfurthii) of the Budongo forest, Uganda. Pant-grunts are one of the most social vocalisations of the chimpanzee vocal repertoire and are always given from a subordinate individual to a dominant. The question of how such a signal is used and develops is critical for our understanding of chimpanzee social and vocal complexity in an ontogenetical and phylogenetical perpective. Results suggest that pant-grunt vocalisations can be used in a flexible way, both in their form and usage within a social group. More specifically, chimpanzees seemed to take into account the number and identity of surrounding individuals before producing these vocalisations. At the acoustic level, pant-grunts seem to be very variable vocalisations that corresponded to different social situations commonly encountered. Grunts are one of the first vocalisations produced by babies but they are not first produced in social contexts. Although some modifications of the social grunts form and usage could not entirely be attributed to maturation only, the role of the mother seemed to be restricted. Her direct influence was perhaps more visible in the rhythmic patterns of chorusing events. Taken together, this thesis suggests that chimpanzee vocalisations are more flexible in their usage, production and acquisition than previously thought and might therefore be more similar to gestural communication.
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12

Magoon, Michael Austin Newland M. Christopher. "Response-consequence contingency discriminability when positive and negative reinforcement compete in concurrent schedules." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Summer/doctoral/MAGOON_MICHAEL_57.pdf.

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13

Bryant, Craig William. "Study of Truck Driver Behavior at Onset of Yellow Traffic Signal Indication for the Design of Yellow Times." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/25149.

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Traffic signal violations by drivers are a leading contributor to crashes at signalized intersections. The yellow indication is used to inform drivers of an upcoming change in the status of the traffic signal. Yellow-interval durations are currently calculated to provide dilemma zone protection for passenger cars. Due to differences in vehicle characteristics and driver characteristics, heavy trucks such as tractor-trailers behave differently at the onset of a yellow-indication. The research presented in this thesis characterizes the difference in driver behavior between truck and light-duty vehicle driver behavior at the onset of yellow-indication and then revises the yellow timing procedures to address the truck requirements. A dataset of 910 stop-go records was collected using a truck driving simulator located at the Virginia Tech Transportation Institute (VTTI). Participant drivers were placed in a simulated urban environment with a speed limit of 45 MPH and instructed to drive as they would regularly drive in such a situation. Participant drivers were recruited using the VTTI participant database. Using the data collected as part of this research effort, statistical models were created to model driver perception-reaction times (PRTs) and deceleration levels considering driver attributes (age) and the time to the intersection at the onset of yellow. The data collected, along with the statistical models developed were compared to data collected and statistical models created by the same research organization in 2008 in a similar study of passenger car driver behavior. Lastly, a Monte-Carlo simulation was conducted to develop appropriate yellow indication timings to provide adequate dilemma zone protection for trucks.
Master of Science
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14

Cai, Qin. "Detecting Chaotic Signals with Nonlinear Models." PDXScholar, 1993. https://pdxscholar.library.pdx.edu/open_access_etds/4564.

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In this thesis we apply chaotic dynamic data analysis to the area of discrete time signal processing. A newly developed Hidden Filter Hidden Markov Model is introduced in detection of chaotic signals. Numerical experiments have verified that this novel nonlinear model outperforms linear AR model in detecting chaotic signals buried by noise having similar power spectra. A simple Histogram Model is proposed which can also be used to do detection on the data sets with chaotic behavior. Receiver Operating Characteristics for a variety of noise levels and model classes are reported.
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15

Diep, Sanh K. "The role of social interactions on the development and honesty of a signal of status." UKnowledge, 2012. http://uknowledge.uky.edu/biology_etds/9.

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Badges of status are supposed to have insignificant production costs, so use costs are thought to be most important in ensuring signal reliability. Use costs arise from the use of the status signal in social interactions. Social experiences that arise from the use of inappropriate signals in social interactions may drive mechanisms that result in reduced fitness for inappropriate signalers. The role of social control, probing and familiarity in producing use costs was explored. There was no evidence that social control by dominants produced a cost for cheaters and no evidence that social control by subordinates produced a cost for inappropriate signaling by Trojans. Probing produced a cost for cheating when resource value was high but not when resource value was low. Familiarity had some effect on the cost and benefit of cheating but in patterns that were not predicted. Familiarity both eliminated a benefit of cheating and reduced a cost of cheating; therefore it is uncertain how familiarity affects honest signaling. The status signal of the receiver had no effect on the cost or benefits of cheating, and there was no evidence of punishment. Social experiences have the potential to affect signal development to produce a correspondence between signal and status. The effects of social experience on signal production were examined and there was little evidence that social experience influenced bib development. Neither aggression expressed nor aggression received was not predictive of bib size. Additionally, tests on the different measures of winning experience produced conflicting conclusions regarding the relationship between winning experience and bib development.
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16

Salazar, Vielka Lineth. "The Effect of male-male competition and its Underlying Regulatory Mechanisms on the Electric Signal of the Gymnotiform fish Brachyhypopomus gauderio." FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/114.

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Sexually-selected communication signals can be used by competing males to settle contests without incurring the costs of fighting. The ability to dynamically regulate the signal in a context-dependent manner can further minimize the costs of male aggressive interactions. Such is the case in the gymnotiform fish Brachyhypopomus gauderio, which, by coupling its electric organ discharge (EOD) waveform to endocrine systems with circadian, seasonal, and behavioral drivers, can regulate its signal to derive the greatest reproductive benefit. My dissertation research examined the functional role of the EOD plasticity observed in male B. gauderio and the physiological mechanisms that regulate the enhanced male EOD. To evaluate whether social competition drives the EOD changes observed during male-male interactions, I manipulated the number of males in breeding groups to create conditions that exemplified low and high competition and measured their EOD and steroid hormone levels. My results showed that social competition drives the enhancement of the EOD amplitude of male B. gauderio. In addition, changes in the EOD of males due to changes in their social environment were paralleled by changes in the levels of androgens and cortisol. I also examined the relationship between body size asymmetry, EOD waveform parameters, and aggressive physical behaviors during male-male interactions in B. gauderio, in order to understand more fully the role of EOD waveforms as reliable signals. While body size was the best determinant of dominance in male B. gauderio, EOD amplitude reliably predicted body condition, a composite of length and weight, for fish in good body condition. To further characterize the mechanisms underlying the relationship between male-male interactions and EOD plasticity, I identified the expression of the serotonin receptor 1A, a key player in the regulation of aggressive behavior, in the brains of B. gauderio. I also identified putative regulatory regions in this receptor in B. gauderio and other teleost fish, highlighting the presence of additional plasticity. In conclusion, male-male competition seems to be a strong selective driver in the evolution of the male EOD plasticity in B. gauderio via the regulatory control of steroid hormones and the serotonergic system.
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17

Kolodziejski, Johanna A. "Signal production and function in weakly electric fish a comparative investigation of sexually dimorphic communication behavior in Apteronotus /." [Bloomington, Ind.] : Indiana University, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3277965.

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Thesis (Ph.D.)--Indiana University, Dept. of Biology, 2007.
Source: Dissertation Abstracts International, Volume: 68-09, Section: B, page: 5788. Adviser: G. Troy Smith. Title from dissertation home page (viewed May 8, 2008).
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18

Pavony, Michelle. "Somatosensory processing and borderline personality disorder a signal detection analysis of proprioception and exteroceptive sensitivity /." Diss., Online access via UMI:, 2009.

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19

Branham, Marc A. "The evolution of Lampyridae, with special emphasis on the origin of photic behavior and signal system evolution (Coleoptera: Lampyridae) /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486402957196158.

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20

Talwar, Malvika. "Evolution of signal frequency in Neoconocephalus (Orthoptera: Tettigoniidae) a study of perceptual and environmental sources of selection /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/5972.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on October 18, 2007) Vita. Includes bibliographical references.
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Goosen, Ryno Johannes. "Sense, signal and software : a sensemaking analysis of meaning in early warning systems." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/96132.

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Thesis (MPhil)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: This thesis considers the contribution that Karl Weick’s notion of sensemaking can make to an improved understanding of weak signals, cues, warning analysis, and software within early warning systems. Weick’s sensemaking provides a framework through which the above mentioned concepts are discussed and analysed. The concepts of weak signals, early warning systems, and Visual Analytics are investigated from within current business and formal intelligence viewpoints. Intelligence failure has been a characteristic of events such as 9/11, the recent financial crisis triggered by the collapse of Lehman Brothers, and the so-called Arab Spring. Popular methodologies such as early warning analysis, weak signal analysis and environmental scanning employed within both the business and government sphere failed to provide adequate early warning in many of these events. These failures warrant renewed attention as to what improvements can be made and how new technology can enhance early warning analysis. Chapter One is introductory and states the research question, methodology, and delimits the thesis. Chapter Two sets the scene by investigating current conceptions of the main constructs. Chapter Three explores Weick’s theory of sensemaking, and provides the analytical framework against which these concepts are then analysed in Chapter Four. The emphasis is directed towards the extent of integration of frames within the analysis phase of early warning systems and how frames may be incorporated within the theoretical foundation of Visual Analytics to enhance warning systems. The findings of this thesis suggest that Weick’s conceptualisation of sensemaking provide conceptual clarity to weak signal analysis in that Weick’s “seed” metaphor, representing the embellishment and elaboration of cues, epitomizes the progressive nature of weak signals. The importance of Weick’s notion of belief driven sensemaking, in specific the role of expectation in the elaboration of frames, and discussed and confirmed by various researchers in different study areas, is a core feature underlined in this thesis. The centrality of the act of noticing and the effect that framing and re-framing has thereon is highlighted as a primary notion in the process of not only making sense of warning signals but identifying them in the first place. This ties in to the valuable contribution Weick’s sensemaking makes to understanding the effect that a specification has on identifying transients and signals in the resulting visualization in Visual Analytic software.
AFRIKAANSE OPSOMMING: Hierdie tesis ondersoek hoe Karl Weick se konsep van singewing ons insig teenoor swak seine, tekens, waarskuwingsanalise en sagteware binne vroeë waarskuwingstelsels verbeter. Weick se bydrae verskaf ‘n raamwerk waarbinne hierdie konsepte geanaliseer en ondersoek kan word. Die konsep van swak seine, vroeë-waarskuwing en visuele analise word binne huidige besigheidsuitgangspunte, en die formele intelligensie arena ondersoek. Die mislukking van intelligensie is kenmerkend van gebeure soos 9/11, die onlangse finansiёle krisis wat deur die ondergang van Lehman Brothers ingelei is, en die sogenaamde “Arab Spring”. Hierdie gebeure het ‘n wêreldwye opskudding op ekonomiese en politiese vlak veroorsaak. Moderne metodologieё soos vroeë waarskuwingsanalise, swaksein-analise en omgewingsaanskouing binne regerings- en besigheidsverband het duidelik in hul doelstelling misluk om voortydig te waarsku oor hierdie gebeurtenisse. Dit is juis hierdie mislukkings wat dit noodsaaklik maak om meer aandag te skenk aan hierdie konsepte, asook nuwe tegnologie wat dit kan verbeter. Hoofstuk Een is inleidend en stel die navorsingsvraagstuk, doelwitte en afbakkening. Hoofstuk Twee lê die fondasie van die tesis deur ‘n ondersoek van die hoof konsepte. Hoofstuk Drie verskaf die teoretiese raamwerk, die van Weick se singewingsteorie, waarteen die hoof konsepte in Hoofstuk Twee ondersoek word in Hoofstuk Vier. Klem word gelê op die diepte van integrasie en die toepassing van raamwerke in die analisefase van vroeё waarskuwingstelsels en hoe dit binne die teoretiese beginsels van visuele analise geïnkorporeer word. Die bevindinge van hierdie tesis spreek die feit aan dat Weick se konsepsualisering van singewing konseptuele helderheid rakende die begrip “swakseine” verskaf. In hierdie verband verteenwoordig Weick se “saad”- metafoor die samewerking en uitbouing van seine en “padpredikante” wat die progressiewe aard van swakseine weerspieёl. Die kernbeskouing van hierdie tesis is die belangrikheid van Weick se geloofsgedrewesingewing, veral die uitkoms van die bou van raamwerke asook die bespreking hiervan deur verskeie navorsers. Die belangrikheid van die aksie om seine op te merk, en die effek wat dit op die herbeskouing van raamwerke het, asook die raaksien daarvan in die eerste plek word beklemtoon. Laasgenoemde dui ook aan tot watter mate Weick se singewingsteorie ‘n bydrae maak tot visuele analise veral in ons begrip van die gevolg wat data of inligtingspesifikasie het op die identifisering van seine en onsinnighede in visualisering binne visuele analise-sagteware.
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Hallberg, Karen Irene. "Information in a long-distance vocal signal chorus howling in the coyote (Canis latrans) /." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1189626727.

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Reynolds, Anna R. "Gαq-ASSOCIATED SIGNALING PROMOTES NEUROADAPTATION TO ETHANOL AND WITHDRAWAL-ASSOCIATED HIPPOCAMPAL DAMAGE." UKnowledge, 2015. http://uknowledge.uky.edu/psychology_etds/74.

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Prolonged, heavy consumption of alcohol produces marked neuroadaptations in excitatory neurotransmission. These effects are accelerated following patterns of intermittent heavy drinking wherein periods of heavy consumption are followed by periods of abstinence. Studies have shown that neuroadaptive changes in the glutamatergic N-methyl-D-aspartate (NMDA) receptor produces excitotoxicity during periods of withdrawal; however, upstream targets were not adequately characterized. The present studies sought to identify these targets by assessing the role of group 1 metabotropic glutamate receptors (mGluR) and intracellular calcium in promoting cytotoxicity of hippocampal cell layers in vitro. It was hypothesized that ethanol-induced activity of mGluR1-and-5 contributes to hippocampal cytotoxicity and promotes the behavioral effects of withdrawal in vivo. In order to identify and test this theory, rat hippocampal explants were co-exposed to chronic intermittent ethanol exposure with or without the addition of a group 1 mGluR antagonist to assess cytotoxicity in neuronal cell types. In a second study, adult male rodents were co-exposed to chronic intermittent ethanol exposure with or without the addition of an mGluR5 antagonist to assess the role of these receptors in the development of dependence as reflected in withdrawal behaviors. Together, these studies help to identify and screen toxicity of putative pharmacotherapies for the treatment of ethanol dependence in the clinical population.
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Smith, David M. "A role for adenylyl cyclase and the CREB/CRE transctiptional pathway in mammalian behavior /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/6296.

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Ehlebracht, Daniel Verfasser], Detlef [Akademischer Betreuer] [Fetchenhauer, and Erik [Akademischer Betreuer] Hölzl. "Doing good does you good : Prosocial behavior as a sexual and social signal / Daniel Ehlebracht. Gutachter: Detlef Fetchenhauer ; Erik Hölzl." Köln : Universitäts- und Stadtbibliothek Köln, 2013. http://d-nb.info/104407356X/34.

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26

Ong, Boon Teck. "Study of Bus Driver Behavior at the Onset of Yellow Traffic Signal Indication for the Design of Yellow Time Durations." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/64454.

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Driver violations at traffic signals are a major cause of intersection vehicle crashes. The yellow interval is used to inform approaching drivers of an upcoming change in the traffic signal indication from green to red. Current yellow-interval durations are currently calculated to accommodate for dilemma zone protection for passenger cars only. Buses with different vehicle, driver, and occupancy characteristics behave differently at the onset of a yellow indication. The research presented in this thesis characterizes the difference between bus and passenger car driver behavior at the onset of yellow-indication. A revised set of yellow timing procedures are presented to address the requirements for bus dilemma zone protection. A dataset of 864 stop-go records were collected as part of the research effort using a school bus approaching a traffic signal on the Virginia Smart Road facility. The experiment was conducted at an instructed speed limit of 57 km/h (35 mph) approach speed where participant drivers were presented with yellow indications. A total of 36 participating bus drivers were randomly selected from three age groups (under 40 years old, 40 to 64 years old and 65 and above) with equal number of male and female for each age group. Using the data collected as part of this research effort, statistical models were created to model bus driver perception-reaction times (PRTs) and deceleration levels considering driver attributes (age and gender), roadway grade, vehicle approach speed, and time to intersection (TTI) at the onset of the yellow indication. A Monte-Carlo simulation was conducted to develop appropriate yellow indication timings to provide adequate dilemma zone protection for buses. Lookup tables were then developed for different reliability levels to provide practical guidelines for the design of yellow signal timings to accommodate different bus percentages within the traffic stream. The recommended change durations can be integrated within the Vehicle Infrastructure Integration (VII) initiative to provide customizable driver warnings prior to a transition to a red indication.
Master of Science
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Ehlebracht, Daniel [Verfasser], Detlef [Akademischer Betreuer] Fetchenhauer, and Erik [Akademischer Betreuer] Hölzl. "Doing good does you good : Prosocial behavior as a sexual and social signal / Daniel Ehlebracht. Gutachter: Detlef Fetchenhauer ; Erik Hölzl." Köln : Universitäts- und Stadtbibliothek Köln, 2013. http://d-nb.info/104407356X/34.

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28

Venator, Kurt Richard. "The Influence of signal attenuation and degradation on behavior and midbrain auditory thresholds in the cricket frog, Acris crepitans blanchardi /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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LaDue, Chase Andrew. "Chemical Signaling in Asian Elephants (Elephas Maximus): Concentration Effects with Applications for Management and Conservation." TopSCHOLAR®, 2016. http://digitalcommons.wku.edu/theses/1622.

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Asian elephants utilize two chemical signals that have been described to function in reproduction: (1) (Z)-7-dodecenyl acetate (Z7-12:Ac) is released by females near ovulation, and (2) frontalin is released by males around the time of musth. Signaling theory posits that the concentration at which either compound is emitted should have implications for the response of the receiver, varying with factors such as sex and reproductive experience. Here, the objectives were to: (1) investigate the effect of concentration on receiver chemosensory behavior in an effort to identify detection thresholds and concentrations of maximum response for reproductively experienced or inexperienced male and female Asian elephants, and (2) characterize the broader behavioral impacts of each of these compounds in an effort for application as environmental enrichment in captive settings. Concentrations from 0.0 mM to 2.0 mM of both frontalin and Z7-12:Ac were bioassayed simultaneously with captive elephants housed at facilities across North America in two experiments: one that tested mid-range concentrations and a second that tested low and high concentrations. There was a general increase in chemosensory response with increasing concentration of both compounds regardless of sex or reproductive experience. Females exhibited a lower detection threshold for frontalin, and the opposite was true for males with Z7-12:Ac. Reproductive experience also influenced thresholds: inexperienced males had a higher threshold than experienced males for frontalin (the same was true for females), and experienced males were able to detect Z7-12:Ac samples as low as 10–7 mM. Aside from inexperienced males, all elephants responded maximally to the 1.0 mM samples of both compounds. Elephants exposed to mid-range concentrations of either compound showed no notable changes in behavior after application of the signals, although inexperienced males spent less time inactive and more time walking after frontalin bioassays, and inexperienced females foraged more after exposure to Z7-12:Ac. Interpreted together, this suggests that the concentration at which either compound is emitted has strong implications for chemosensory response based on the identity of the receiver in Asian elephants, although it is unclear whether these compounds have other behavioral effects that can be targeted for a goal-oriented olfactory enrichment program.
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Gooch, Steven R. "A METHOD FOR NON-INVASIVE, AUTOMATED BEHAVIOR CLASSIFICATION IN MICE, USING PIEZOELECTRIC PRESSURE SENSORS." UKnowledge, 2014. http://uknowledge.uky.edu/ece_etds/56.

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While all mammals sleep, the functions and implications of sleep are not well understood, and are a strong area of investigation in the research community. Mice are utilized in many sleep studies, with electroencephalography (EEG) signals widely used for data acquisition and analysis. However, since EEG electrodes must be surgically implanted in the mice, the method is high cost and time intensive. This work presents an extension of a previously researched high throughput, low cost, non-invasive method for mouse behavior detection and classification. A novel hierarchical classifier is presented that classifies behavior states including NREM and REM sleep, as well as active behavior states, using data acquired from a Signal Solutions (Lexington, KY) piezoelectric cage floor system. The NREM/REM classification system presented an 81% agreement with human EEG scorers, indicating a useful, high throughput alternative to the widely used EEG acquisition method.
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31

Cournault, Laurent. "Regulation of reproduction in polygynous ants (Dolichoderinae): queen fertility signal and adult polyploidy." Doctoral thesis, Universite Libre de Bruxelles, 2009. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210332.

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Regulation of reproduction is one central feature of social life. In particular, only a few individuals are in charge of producing offspring in eusocial species. This division of the reproductive labour is mainly mediated by pheromones emitted by the queens in social insects. These queen pheromones may signal the presence of a fertile queen so that workers react accordingly by taking care of her and not reproducing.

Here I investigated two aspects of the reproduction of two polygynous ant species. The first one, Linepithema humile, is a unicolonial, highly polygynous and invasive species. It has been the focus of numerous studies about queen pheromones; in particular, it has been reported that queen cuticular hydrocarbons (CHC) profile is related to queen fertility. The other one, Tapinoma erraticum, is a multi-colonial, weakly polygynous and native species. Workers can lay haploid eggs in the absence of the queens which is impossible for Linepithema workers.

The major part of my thesis dealt with the queen fertility signalling issue. In the first two chapters I demonstrate the link between queen fertility and queen pheromone output. I first study a queen releaser pheromone, the queen retrieval behaviour. This behaviour is performed by the workers who lay a chemical trail toward a queen located outside the nest. I successfully show this behaviour to be related to queen fertility, and not mating status, in L. humile and T. erraticum since only fertile queens (mated or not) induce such recruitment. I then highlight the role of queen fertility in the prevention of worker reproduction in T. erraticum. Again, mated fertile queens and unmated fertile queens are both able to induce such primer effect. In a third chapter I report that CHC profiles may discriminate female castes (workers, queens, virgin queens, and virgin egg-laying queens) in T. erraticum. Finally, chapter 4 summarizes my attempts to prove that CHC may be involved in queen retrieval or queen attraction. None of the various bioassays tested allows me to demonstrate the putative role of CHC as queen pheromone.

In a second part, I was interested in the consequences of sex determination in T. erraticum. Chapter 5 presents the flow cytometry methodology (FC) which allowed me to score the number of sperm cells from spermathecae of several ant species, and to demonstrate that polygynous species (such as L. humile and T. erraticum) store less sperm than monogynous ones. FCM also allows determining the ploidy of sperm and adult somatic cells and chapter 6 which presents a large survey on the ploidy level within the species T. erraticum. This species displays diploid males that may produce diploid sperm which in turn can father a viable triploid female progeny. I report differences in the frequency of triploidy among female castes, the proportion of triploid workers being more important than triploid virgin queens whereas I never observed triploid mated fertile queens. Such results greatly suggest a putative regulatory mechanism involved in the rearing of triploid females. In the last chapter I investigated two populations that differ in the occurrence of triploid workers. I report these populations to vary in the number of queens and workers per nest.

/La régulation de la reproduction est un aspect essentiel de la vie sociale. En particulier, chez les espèces eusociales, seuls quelques individus sont impliqués dans la production de la descendance. Dans les sociétés d’insectes, une telle division du travail reproducteur est principalement assurée par l’émission de phéromones par les reines. Ces phéromones royales renseignent les membres de la colonie sur la présence d’une reine fertile, de telle sorte que les ouvrières réagissent en s’occupant d’elle et en s’abstenant de se reproduire.

Au cours de ce travail, je me suis intéressé à deux aspects de la reproduction au sein de deux espèces de fourmis polygynes. La première espèce, Linepithema humile, est invasive, unicoloniale et hautement polygyne dans les régions à climat méditerranéen. Elle a fait l’objet de nombreuses études portant notamment sur les phéromones royales. En particulier, il a été montré que le profil d’hydrocarbures cuticulaires (HCC) des reines est corrélé à leur fertilité. La seconde espèce, Tapinoma erraticum, est une espèce indigène, multi-coloniale et faiblement polygyne. Ses ouvrières sont capables de pondre des œufs mâles en absence de reines, ce dont sont incapables les ouvrières de Linepithema.

Je me suis principalement intéressé à la question de la signalisation de la fertilité des reines. Dans les deux premiers chapitres, je démontre le lien existant entre la fertilité des reines et la production de phéromone royale. J’ai d’abord étudié une phéromone incitatrice (releaser) qui provoque un recrutement royal. Ce comportement collectif très caractéristique correspond à la mise en place d’une piste chimique en direction d’une reine découverte par les ouvrières en dehors du nid. Je montre que ce comportement est lié à la fertilité de la reine chez les espèces L. humile et T. erraticum car seules les reines fertiles (fécondées ou non) sont capables de d’induire le recrutement royal. Je mets ensuite en évidence le rôle de la fertilité des reines dans la régulation de la reproduction des ouvrières de T. erraticum. A nouveau, les reines fécondées fertiles et les reines vierges fertiles sont toutes deux capables d’induire un même effet déclencheur (primer), en l’occurrence, l’inhibition de la reproduction des ouvrières. Dans un troisième chapitre, je montre que les profils d’hydrocarbures (HCC) permettent de distinguer sans ambiguïté les différentes castes femelles (ouvrières, reines fertiles, reines vierges et reines vierges pondeuses) chez T. erraticum. Enfin, le chapitre 4 résume mes tentatives pour démontrer le rôle des HCC dans les phénomènes de recrutement royal ou d’attractivité des reines. Aucun des bio-essais réalisés ne me permet de démontrer l’implication des HCC dans la phéromone royale.

Dans une seconde partie, je me suis intéressé aux conséquences du déterminisme du sexe chez T. erraticum. Le chapitre 5 présente cytométrie de flux (CF), une méthode qui me permet de compter les spermatozoïdes stockés dans les spermathèques de quelques espèces de fourmis et de montrer que les reines des espèces polygynes (telles que L. humile et T. erraticum) stockent moins de sperme que les espèces monogynes. La CF permet aussi de déterminer le niveau de ploïdie des cellules spermatiques ou somatiques chez l’adulte. Je me sers de cette application dans le chapitre 6 afin d’étudier le niveau de ploïdie au sein de l’espèce T. erraticum. Je montre que, dans les populations étudiées, il existe des mâles diploïdes et que ces mâles peuvent produire du sperme diploïde fertile, capable d’engendrer une descendance femelle triploïde. Je note des différences dans la fréquence des femelles triploïdes :la proportion d’ouvrières triploïdes est significativement plus importante que celle des reines vierges triploïdes. De plus, je n’ai jamais observé la présence de reines fécondées fertiles triploïdes. De tels résultats suggèrent fortement la présence d’un phénomène de régulation au cours de l’élevage du couvain triploïde. Dans le dernier chapitre, j’ai étudié deux populations de T. erraticum qui diffèrent au niveau de la proportion d’ouvrières triploïdes. Ces populations présentent des différences significatives dans le nombre de reines et d’ouvrières par nid.


Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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32

Olsen, Erik Charles Buck. "Modeling Slow Lead Vehicle Lane Changing." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/29889.

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Driving field experiment data were used to investigate lane changes in which a slow lead vehicle was present to: 1) characterize lane changes, 2) develop predictive models, 3) provide collision avoidance system (CAS) design guidelines. A total of 3,227 slow lead vehicle lane changes over 23,949 miles were completed by sixteen commuters. Two instrumented vehicles, a sedan and an SUV, were outfitted with video, sensor, and radar data systems that collected data in an unobtrusive manner. Results indicate that 37.2% of lane changes are slow lead vehicle lane changes, with a mean completion time of 6.3 s; most slow lead vehicle lane changes are leftward, rated low in urgency and severity. A stratified sample of 120 lane changes was selected to include a range of maneuvers. On the interstate, lane changes are performed less often, t(30) = 2.83, p = 0.008, with lower urgency ratings, F(1, 31) = 5.24, p = 0.05, as compared to highway lane changes, as interstates are designed for smooth flow. Drivers who usually drive sedans are more likely to make lane changes than drivers of SUVs, X ²⁺(1)= 99.6247, p < 0.0001, suggesting that driving style is maintained regardless of which experimental vehicle is driven. Turn signals are used 64% of the time but some drivers signal after the lane change starts. Of cases in which signals are not used, 70% of them are made with other vehicles nearby. Eyeglance analysis revealed that the forward view, rearview mirror, and left mirror are the most likely glance locations. There are also distinct eyeglance patterns for lane changing and baseline driving. Recommendations are to use forward view or mirror-based visual displays to indicate presence detection, and auditory displays for imminent warnings.  The "vehicle + signal" logistic regression model is best overall since it takes advantage of the distance to the front and rear adjacent vehicle, forward time-to-collision (TTC), and turn signal activation. The use of additional regressors would also improve the model. Five design guidelines are included to aid in the development of CAS that are useable, safe, and integrated with other systems, given testing and development.
Ph. D.
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33

Dumont, Emmanuel. "Collaboration entre un humain, un robot et un système ambiant pour l’évaluation de comportements." Thesis, Compiègne, 2019. http://www.theses.fr/2019COMP2484/document.

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Évaluer un comportement humain c’est évaluer tous les marqueurs traduisant ce comportement (gestes, paroles interactions, etc.). L’observation par un humain de certains marqueurs tels que les expressions faciales, la prosodie ou encore la linguistique, nécessite une formation spécialisée. Pour faciliter l’évaluation du comportement, des échelles indiquant les observations à mener et les conclusions à faire sont employées. Ainsi, automatiser l’évaluation du comportement revient à automatiser l’analyse d’un environnement par le biais de plusieurs capteurs, puis analyser les signaux obtenus afin d’en extraire les marqueurs permettant la déduction du comportement observé. Suite à la variabilité des observations de l’humain lors d’analyses trop spécifiques, de plus en plus d’études emploient ces systèmes automatiques d’observation et d’évaluation du comportement. L’objectif est d’assister l’analyse et l’évaluation humaine en exploitant des systèmes automatiques capables d’extraire des informations difficilement observables pour l’humain. En conséquence, la collaboration entre l’humain et les systèmes informatiques permet d’analyser plus d’éléments du comportement de manière fiable et objective. Cette thèse propose une approche de l’analyse du comportement s’appuyant sur la collaboration entre l’humain et un système automatique. Nous avons mis en place une plate-forme électronique et informatique composée d’un robot mobile et d’un système ambiant afin d’évaluer le comportement humain. Cette plate-forme se définie comme étant : — Modulaire à l’ajout ou le retrait de capteurs : L’ajout et la suppression de capteurs est faisable sans qu’un système ne soit impacté autrement que sur ses performances à reconnaître précisément les comportements; — Accessible à la lecture des données enregistrées : L’utilisation d’ontologies, en tant que base de données sémantiques et logiques, rend la plate-forme utilisable et accessible aux personnes non familiarisées aux systèmes informatiques complexes; — Robuste aux ambiguïtés : Chaque système de la plate-forme (ambiant ou robot) est indépendant et a sa propre représentation de l’environnement. Cependant, ils collaborent entre eux pour répondre aux incohérences ou aux manques d’informations durant l’accomplissement d’une tâche. A partir de la plate-forme présentée précédemment, nous analysons et mesurons la qualité de l’interaction entre un patient et un soignant lors d’une prise de sang réalisée en conditions habituelles. Pour cela, nous utilisons deux méthodes de renseignement des échelles : par un observateur présent lors du soin et par une étude de l’enregistrement vidéo réalisé durant le soin par la plate-forme. Nous émettons l’hypothèse que la présence d’un système automatique d’aide au diagnostic lors de l’analyse des vidéos enregistrées limite la complexité de l’évaluation du comportement et améliore l’objectivité de l’analyse
To evaluate a human behavior is equivalent to evaluate all the markers translating this behavior (gestures, lyrics interactions, etc.). The observation by a human of certain markers such as facial expressions, prosody or linguistics, requires specialized training. To facilitate the assessment of behavior, scales indicating the observations to be made and the conclusions to be made are used. Thus, automating the evaluation of the behavior amounts to automate the analysis of an environment by means of several sensors, then analyzing the signals obtained in order to extract the markers allowing the deduction of the observed behavior. Due to the variability of human observations in overly specific analyzes, more and more studies are using thes automatic observation and behavioral evaluation systems. The objective is to assist human analysis and evaluation by exploiting automatic systems capable of extracting information that is difficult to observe for humans. As a result, the collaboration between the human and the computer systems makes it possible to analyze more elements of the behavior in a reliable and objective way. This thesis proposes an approach of behavior analysis based on the collaboration between humans and an automatic system. We set up an electronic and computer platform consisting of a mobile robot and an ambient system to evaluate human behavior. This platform is defined as: — Modular to the addition or removal of sensors: The addition and removal of sensors is feasible without a system is impacted otherwise than its performance to accurately recognize behaviors; — Accessible to Reading Recorded Data: The use of ontologies, as a semantic and logical database, makes the platform usable and accessible to people unfamiliar With complex computer systems; — Robust to ambiguities: every platform system (ambient or robot) is independent and has its own representation of the environment. However, they collaborate With each Other to respond to inconsistencies or lack of information during the performance of a task
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34

Yu, Xiaoyang. "Dynamic acoustic emission for the characterization of the nonlinear behavior of complex materials." Thesis, Le Mans, 2020. http://www.theses.fr/2020LEMA1019.

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L’émission acoustique (EA) est reconnue pour être une technique efficace de surveillance de la santé des structures permettant de détecter la création et la propagation de microfissures dans les matériaux structuraux tels que le béton ou les composites lorsqu'ils sont soumis à des contraintes quasi-statiques. Sur la base de méthodes de traitement de signaux adéquates, différentes études ont établi des liens entre les salves d’EA et les micro-dommages créés. D'autres travaux ont montré qu'il est possible de corréler le temps de relaxation des composites et l'énergie des mécanismes d'endommagement mesurée durant la charge quasi-statique en utilisant les salves d’EA enregistrées. Cette thèse propose d'utiliser un protocole expérimental original pour détecter la relaxation non-linéaire d'échantillons de bétons à l'état intact et endommagés. Ce protocole est basé sur l'utilisation de l’EA pour capter passivement la relaxation non-linéaire d'échantillons de bétons au lieu du signal de faible amplitude habituellement utilisé dans les expériences de dynamique lente. Les résultats montrent que les méthodes de détection passives et actives conduisent à des temps de relaxation équivalents. De plus, le capteur d’EA révèle l’existence d’une ‘période de silence’ pendant les premières minutes de la relaxation non-linéaire après laquelle les salves d’EA commencent à être détectées. De plus, les caractéristiques des salves d’EA enregistrées pendant la relaxation passive ont montré une nette ressemblance avec celles obtenues lors de l'endommagement des mêmes échantillons, où des mécanismes de cisaillement et de compression sont impliqués. Enfin, nous notons qu’en plus de l'utilisation d'une approche de reconnaissance des formes non- supervisée pour la classification des salves d’EA, ce travail propose une nouvelle approche de classification des signaux d’EA basé sur l’image de la représentation en ondelettes continue (CWT) et le réseau de neurones convolutifs (CNN). Les résultats liés aux données d’EA dynamiques non-linéaires et quasi-statiques montrent que les deux approches de traitement du signal ont une grande précision de classification, ce qui représente un intérêt certain pour le développement de méthodes d’EA dynamiques en présence de microfissures
Acoustic emission (AE) is well known to be an efficient structural health monitoring technique to detect the creation and propagation of micro-cracks within structural materials such as concrete or composites when submitted to quasi-static stresses. Based on adequate signal processing methods, different research studies have established links between the detected AE hits and the created micro-damages. Other works have shown that it is possible to correlate the relaxation time in composites and the energy of the damage mechanisms measured during the quasi-static loading using the recorded AE hits. This thesis proposes to use an original experimental protocol to probe the nonlinear relaxation of concrete samples at the intact and damaged states. This protocol is based on the use of AE to passively probe the nonlinear relaxation of concrete samples instead of the weak amplitude signal usually used in slow dynamics experiments. Results show that passive and active probing methods lead to equivalent relaxation times. Furthermore, AE probing reveals the existence of a ‘silence period’ during the first minutes of the nonlinear relaxation after which AE hits start to be detected. In addition, the characteristics of AE hits recorded during the passive relaxation showed a clear resemblance to those obtained during the damaging of the same samples, where shear and compression mechanisms are involved. For the clustering of the AE hits, in addition to use of an unsupervised pattern recognition approach to cluster the detected AE hits, this work proposes a novel ‘image- based AE classification’ approach based on continuous wavelet transform (CWT) and convolutional neural network (CNN). Results related to the nonlinear dynamic and quasi-static AE data show that both signal processing approaches have high classification accuracy, which represents a great interest in the development of dynamic AE methods in the presence of micro-cracks
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35

Moretz, Jason A. "A Comparative Analysis of the Role of Male – Male Competition in the Evolution of Aggression, Vertical Bars and Male Body Size in the Northern Swordtail Fishes." Ohio University / OhioLINK, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1090936908.

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36

Narango, Desiree Lynn. "Causes and Consequences of Urban-associated Song Variation: A Study of Vocal Behavior in the Northern Cardinal (Cardinalis cardinalis)." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1337792731.

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37

Kim, Jonathan Chongkang. "Classification of affect using novel voice and visual features." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54301.

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Emotion adds an important element to the discussion of how information is conveyed and processed by humans; indeed, it plays an important role in the contextual understanding of messages. This research is centered on investigating relevant features for affect classification, along with modeling the multimodal and multitemporal nature of emotion. The use of formant-based features for affect classification is explored. Since linear predictive coding (LPC) based formant estimators often encounter problems with modeling speech elements, such as nasalized phonemes and give inconsistent results for bandwidth estimation, a robust formant-tracking algorithm was introduced to better model the formant and spectral properties of speech. The algorithm utilizes Gaussian mixtures to estimate spectral parameters and refines the estimates using maximum a posteriori (MAP) adaptation. When the method was used for features extraction applied to emotion classification, the results indicate that an improved formant-tracking method will also provide improved emotion classification accuracy. Spectral features contain rich information about expressivity and emotion. However, most of the recent work in affective computing has not progressed beyond analyzing the mel-frequency cepstral coefficients (MFCC’s) and their derivatives. A novel method for characterizing spectral peaks was introduced. The method uses a multi-resolution sinusoidal transform coding (MRSTC). Because of MRSTC’s high precision in representing spectral features, including preservation of high frequency content not present in the MFCC’s, additional resolving power was demonstrated. Facial expressions were analyzed using 53 motion capture (MoCap) markers. Statistical and regression measures of these markers were used for emotion classification along the voice features. Since different modalities use different sampling frequencies and analysis window lengths, a novel classifier fusion algorithm was introduced. This algorithm is intended to integrate classifiers trained at various analysis lengths, as well as those obtained from other modalities. Classification accuracy was statistically significantly improved using a multimodal-multitemporal approach with the introduced classifier fusion method. A practical application of the techniques for emotion classification was explored using social dyadic plays between a child and an adult. The Multimodal Dyadic Behavior (MMDB) dataset was used to automatically predict young children’s levels of engagement using linguistic and non-linguistic vocal cues along with visual cues, such as direction of a child’s gaze or a child’s gestures. Although this and similar research is limited by inconsistent subjective boundaries, and differing theoretical definitions of emotion, a significant step toward successful emotion classification has been demonstrated; key to the progress has been via novel voice and visual features and a newly developed multimodal-multitemporal approach.
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38

Shabani, Shkelzen. "The Role of Chemical Senses in Predation, Risk Assessment, and Social Behavior of Spiny Lobsters." Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/biology_diss/44.

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Chemical senses play a critical role in predator-prey and social interactions of many animals. Predators often evoke adaptive escape responses by prey, one of which is the release of chemicals that induce adaptive avoidance behaviors from both predators and conspecifics. I explore the use of chemicals in predator-prey and social interactions, using a crustacean model system, the spiny lobster. As predators, spiny lobsters are opportunistic, polyphagous feeders, and they rely heavily on their chemical senses during feeding. Some of their potential prey deter attacks through chemical defenses that act through the spiny lobsters’ chemical senses. An example of this is sea hares, Aplysia californica, which secrete an ink when vigorously attacked by sympatric spiny lobsters, Panulirus interruptus. I show that that this ink defends sea hares from spiny lobsters through several mechanisms that include phagomimicry, sensory disruption, and deterrence, and that the ink’s efficacy is enhanced by its naturally high acidity. As prey, spiny lobsters rely heavily on their chemical senses to assess risk from predators. One way to assess risk of predation is through ‘alarm cues’, which are injury-related chemicals. I show that injured Caribbean spiny lobsters, Panulirus argus, release alarm cues in their hemolymph, and that nearby conspecifics detect these cues using olfaction. Hemolymph from conspecifics induces primarily alarm behavior in the form of retreat, sheltering, and suppression of appetitive responses. In contrast, hemolymph from heterospecifics, depending on phylogenetic relatedness, induces either mixed alarm and appetitive behaviors or primarily appetitive behaviors. Spiny lobsters also use chemical cues to assess risk during social interactions with conspecific. I show that spiny lobsters use urine-borne chemical signals and agonistic behaviors to communicate social status and that these chemical signals are detected exclusively by the olfactory pathway. Dominant animals increase urine release during social interactions, whereas subordinates do not. Experimental prevention of urine release during interactions causes an increase in agonism, but this increase is abolished when urine of dominants is reintroduced. My findings lay the foundation for neuroethological studies of risk-assessment systems mediated by intraspecific chemical cues.
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Harirforoush, Homayoun. "Evaluation of the LHOVRA O-function using the microsimulation tool VISSIM." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-87757.

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The growth of serious injuries and fatalities resulting from traffic accidents at intersections is one of the main problems in urban areas. Signal control was proposed as an alternative intersection design on rural roads. There were many reasons behind this, the most outstanding of which was the traffic signals can be used as a cost effective tools for traffic management in urban areas. The LHOVRA technique was intended to improve safety and reduce lost time at signalized intersection along high speed roads. The LHOVRA technique is an isolated traffic control strategy in Sweden which is formed from different concepts. This thesis work is aimed to evaluate the LHOVRA technique with a focus on the O-function. Hence, two different scenarios, one with O-function and one without O-function were implemented in the micro traffic simulation software, VISSIM. VISSIM has been used to simulate the traffic situation of the Gamla Övägen – Albrektsvägen intersection by considering the LHOVRA scenario (with O-function) as well as traditional scenario (without O-function) of the intersection. Field measurements were used as input data for VISSIM simulation. The VISSIM simulation model was calibrated to find a close match between simulated and real data. Finally, a comparison of alternatives was carried out based on traffic performance and traffic safety measurements. The simulation experiment results gained by the comparisons were presented a higher time-to-collision value. The higher time-to-collision value the safer situation is. Both delays and travel time were reduced to primary road traffic.
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Cardoso, Alexandre Moraes. "Manejo de Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) em milho, Zea mays L.: bases para avaliação populacional e controle biológico utilizando o parasitóide de ovos Trichogramma atopovirilia Oatman & Platner, 1983 (Hymenoptera:Trichogrammatidae)." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/59/59131/tde-25042007-155956/.

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A presente pesquisa teve como objetivos aprimorar a amostragem de Spodoptera frugiperda através do uso de armadilhas com feromônio sexual, verificar a capacidade de dispersão de Trichogramma atopovirilia como agente de controle biológico desta praga bem como avaliar a atratividade de Amaranthus sp. às fêmeas de T. atopovirilia. Para aprimorar a amostragem de S. frugiperda, os estudos foram conduzidos em dois campos comerciais de produção de milho, sendo um composto de 36,3 ha (denominado de MIP e com 30 pontos de amostragem) e outro de 10 ha (denominado de convencional e com 10 pontos de amostragem). Nestes campos foram instaladas armadilhas com feromônio sexual, distribuídas de forma aleatória e na proporção de 1 armadilha / ha. As avaliações foram realizadas duas vezes por semana durante todo o desenvolvimento das plantas, considerando-se: número de adultos machos coletados pelas armadilhas, injúria dos insetos às plantas, número de posturas e de larvas (pequenas, médias e grandes). O número de adultos coletados nas armadilhas foi correlacionado com os níveis de injúrias, número de posturas e densidade larval. O número de larvas observadas não apresentou diferença entre áreas e pontos de amostragem. A injúria dos insetos às plantas, número de posturas e de larvas pequenas não apresentaram correlação com os adultos capturados pelas armadilhas. Houve correlação significativa entre o número de larvas grandes (4o e 5o ínstares) e o número de plantas apresentando o cartucho furado ou destruído. Não houve correlação da coleta de adultos nas armadilhas com a infestação ou níveis de injúria, demonstrando que as larvas ainda precisam ser contadas para determinar o momento do seu controle. A capacidade de dispersão de T. atopovirilia foi estudada em 3 fases distintas de desenvolvimento das plantas de milho, quando estas possuíam de 4 a 6 folhas, 8 a 10 folhas e pendoamento. Em cada fase foi realizada uma infestação artificial com posturas (até 24 h) de S. frugiperda nas plantas localizadas em distâncias que variaram de 6 a 24 m do ponto de liberação do parasitóide. Logo após esta infestação, foi realizada somente uma liberação de adultos do parasitóide para cada fase da cultura e sempre no período mais fresco do dia (manhã ou entardecer). O parasitismo foi permitido durante até 48 horas quando as posturas eram recolhidas e acondicionadas em câmara climatizada até a emergência dos adultos. Os resultados indicaram que as plantas em suas diferentes fases de desenvolvimento afetaram a capacidade de dispersão dos parasitóides. As posturas localizadas nos pontos mais distantes somente foram atingidas pelos parasitóides durante a fase de desenvolvimento da cultura em que as plantas de milho estavam menores (4 a 6 folhas). Nas outras fases, os índices de parasitismo foram maiores naquelas posturas localizadas mais próximas do ponto de liberação. A atratividade de quatro espécies de Amaranthus (A. retroflexus, A. viridis, A. hybridus e A. spinosus) às fêmeas de T. atopovirilia foram avaliadas utilizando-se olfatômetro Peterson. Estas plantas foram testadas em período de desenvolvimento vegetativo e reprodutivo. Adotou-se o delineamento inteiramente casualizado com 40 repetições (considerando-se um inseto/ repetição) e cada inseto foi observado durante o tempo máximo de 600 segundos. As espécies mais atrativas foram A. viridis e A. retroflexus, nos estádios vegetativo e reprodutivo, respectivamente. Quando testadas simultaneamente, as espécies de plantas não demonstraram atratividade ao parasitóide. Estes resultados sugerem a viabilidade do uso destas plantas ou seus derivados no manejo de habitats de hospedeiros e aumento de parasitismo em programas de manejo integrado de pragas.
The objectives of this research were the improvement of cross-section Spodoptera frugiperda using pheromone traps to verify the capacity of dispersion of Trichogramma atopovirilia as an agent for biological pest control as well as evaluating the attractiveness of Amaranthus sp. to T. atopovirilia females. To improve cross-section of S. frugiperda, the studies were carried out in two commercial corn field plantations, one made up of 36,3 ha (called MIP and with 30 points of sampling) and another of 10 ha (called conventional and with 10 points of sampling). In these fields pheromone traps were randomly displaced (ratio of 1 trap/ha). The evaluations were realized twice a week during the whole plant development, considering : number of male adults collected by the traps, insect injury to plants, egg masses and larval densities (small, medium and large). The numbers of adults collected were correlated to the insect injury, egg masses and larval density. The larval occurrence did not show difference between areas and sampling points. The injury levels, egg masses and small larva densities did not show correlation to adult caught by traps. There was significant correlation between large larvae (4th and 5th instars) and the number of plants showing whorl holes and/or destroyed ones. There were no correlations observed among adults caught by traps and insect infestation or injury, so demonstrating that larvae should be counted for timing pest control. The capacity of dispersion of T. atopovirilia was studied in 3 distinct phases of corn plant development, when they had 4 to 6 leaves, 8 to 10 leaves and tassel. In each stage was applied an artificial infestation with egg masses (< 24 h) of S. frugiperda on plants located 6 to 24 m from a parasitoid release point. Right after this artificial infestation, was applied only one parasitoid adult release to each distinct corn plant phase , always early in the morning or late in the afternoon. The parasite contamination was allowed during 48 h and then the egg masses were retrieved and taken into a climatic chamber until emerging adulthood. The results showed that plants affected the parasitoid dispersal. The egg masses placed farthest from the release point were parasited only during the 4 to 6-leaf stage. In the others stages, only egg masses next to the release point were parasited. The attractiveness of four species of Amaranthus (A. retroflexus, A. viridis, A. hybridus and A. spinosus) to the females of T. atopovirilia was evaluated by a Petersons olfactometer. These plants were evaluated in both vegetative and reproductive stages. Complete randomized procedure was adopted with 40 replications (considering one insect/replication) and each insect was observed during 600 seconds. The most attractive species were A. viridis and A. retroflexus during vegetative and reproductive stage, respectively. When plants were tested simultaneously, the species did not show attractive properties to the parasitoids. These results suggest the viability of the use of these plants or its derivatives to change host habitat and parasite increase for biological control in integrated pest management.
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41

Alderson, Robert. "ADHD AND STOP-SIGNAL BEHAVIORAL INHIBITION: IS MEAN REACTION TIME CONTAMINATED BY EXPOSURE TO INTERMITTENT STOP-SIGNALS?" Doctoral diss., University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2464.

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The current study investigates two recently identified threats to the construct validity of behavioral inhibition as a core deficit of attention-deficit/hyperactivity disorder (ADHD) based on the Stop-signal task: calculation of mean reaction time from go-trials presented adjacent to intermittent stop-trials, and non-reporting of the stop-signal delay metric. Children with ADHD (n=12) and typically developing children (TD) (n=11) were administered the standard stop-signal task and three variant stop-signal conditions. These included a No-Tone condition administered without the presentation of an auditory tone; an Ignore-Tone condition that presented a neutral (i.e., not associated with stopping) auditory tone; and a second Ignore-Tone condition that presented a neutral auditory tone after the tone had been previously paired with stopping. Children with ADHD exhibited significantly slower and more variable reaction times to go-stimuli, and slower stop-signal reaction times (SSRT) relative to TD controls. Stop-signal delay (SSD) was not significantly different between groups, and both groups' go-trial reaction times slowed following meaningful tones. Collectively, these findings corroborate recent meta-analyses and indicate that previous findings of stop-signal performance deficits in ADHD reflect slower and more variable responding to visually presented stimuli and concurrent processing of a second stimulus, rather than deficits of motor behavioral inhibition.
Ph.D.
Department of Psychology
Sciences
Psychology PhD
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42

Alderson, Robert Matthew. "ADHD and stop-signal behavioral inhibition is mean reaction time contaminated by exposure to intermittent stop-signals? /." Orlando, Fla. : University of Central Florida, 2008. http://purl.fcla.edu/fcla/etd/CFE0002218.

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43

GOMES, RENATO ARREGUI. "RADIO SIGNAL BEHAVIOUR ON MICROCELLULAR MOBILE ENVIRONMENTS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1999. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7473@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
Com o aumento da demanda pelos serviços celulares se faz necessário estudar e desenvolver técnicas cada vez mais sofisticadas para a melhoria da capacidade e da qualidade dos sistemas celulares. Uma destas é a utilização moderada de microcélulas em regiões urbanas, e em algumas situações em regiões suburbanas. Os maiores problemas da utilização de microcélulas são suas características de propagação, bem diferentes das características das células convencionais. Para melhor compreender as características de propagação de um sinal rádio móvel num ambiente microcelular, este trabalho se propôs a fazer um estudo experimental onde, fenômenos como forma de células, efeitos de sombreamento, multipercurso e outros, foram analisados. Um laboratório móvel foi montado e uma grande campanha de medidas foi realizada em ambientes urbanos de características diferentes. Análises determinísticas e estatísticas, foram realizadas para se determinar parâmetros como o fator de queda do sinal com a distância e o desvio padrão da variabilidade do sinal. Estes resultados são importantes para o cálculo aproximado da cobertura do sinal em regiões semelhantes às estudadas. Especial atenção foi dada ao cálculo do ponto de quebra da dependência do sinal com a distância. Este ponto define a transição entre a região de campo próximo e a região de difração, sendo fundamental para estudos de cobertura. Uma importante contribuição foi na determinação da dependência da cobertura do sinal com a altura da antena transmissora. Os resultados medidos ajudaram a caracterizar a célula e conseqüentemente obter informações para localizações ótimas das altura das antenas, além de definir a melhor cobertura que estas alturas podem oferecer. Uma análise estatística da variabilidade do sinal foi realizada e distribuições de probabilidade foram testados frente aos resultados experimentais. A determinação de parâmetros importantes destas distribuições ajudou na verificação da aderência destes modelos aos resultados medidos. Os resultados são de extrema importância para esclarecer aspectos de propagação do sinal em microcélulas e disponibilizar dados para a elaboração de modelos de predição para o cálculo da cobertura do sinal para o projetista, resultando numa melhoria da qualidade e da capacidade do sistema microcelular.
The ever-increasing demand for cellular services raises the necessity of developing more sophisticated techniques to improve system quality and capacity. One of the techniques is the use of microcells in urban and occasionally suburban regions. However, the major problems facing the microcell deployment are the microcells peculiar propagation characteristics, which are very different from the conventional cellular systems. In order to address this problem, an experimental study of cell shape, shadowing effects and multipath, was carried out. A mobile laboratory was assembled and extensive measurements on different urban environments were performed. Deterministic and statistical analysis were carried out to find the parameters such as path loss versus distance factor, and the standard deviation of signal variability. Special attention was given to the determination of the breaking point, transition between the near field and diffraction regions on line-of-sight path. An important contribution was on the study of the effects of transmitter antenna height on coverage. The measured results will help on cell characterization and on finding the best height for the base station antennas. A statistical analysis of signal variability was performed to determine the best-fit probability distribution function with parameters carefully calculated. The collected results are of extreme importance to clarify propagation aspects of microcellular signal and to make it available a huge data bank for elaboration of better prediction models which will produce better quality and capacity of the microcellular systems.
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44

Garcia, Thomas. "A behavioral approach of decision making under risk and uncertainty." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/132313/1/Thomas%20Jean-Christophe%20Lucien_Garcia_Thesis.pdf.

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This thesis investigates how individuals make decisions under risk and uncertainty. It is composed of four essays that theoretically and experimentally investigate decision-making. First, I study situations where individuals must decide whether an event has occurred using uncertain evidence. I highlight that individuals tend to maximize accuracy instead of maximizing expected payoffs. I find that it is partially due to the existence of a value of being right and a recency bias. Second, I study how ambiguity on the costs or the benefits of a donation affects donation behavior. I show that individuals use ambiguity strategically as an excuse to behave less generously without feeling guilty. Finally, I study the external validity of risk preference measures based on a representative panel of the Dutch population. I find that risk-preference measures are related to behavior in experimental risk tasks, however they are not related to risk-taking in the field.
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45

Garcia, Thomas. "A behavioral approach of decision making under risk and uncertainty." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE2042/document.

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Cette thèse porte sur la façon dont les individus prennent des décisions en présence de risque et d'incertitude. Elle est composée de quatre essais qui étudient théoriquement et expérimentalement la prise de décision.Les deux premiers essais étudient des situations où un décideur doit décider si un événement a eu lieu en utilisant des informations incertaines. Le fait d'identifier correctement que cet événement s'est produit est plus rémunéré que le fait d'identifier correctement qu'il ne s'est pas produit. Ce problème de décision induit une divergence entre deux qualités d'une décision : l'optimalité et l'exactitude. Les deux essais reproduisent de telles situations dans une expérience de laboratoire basée sur des tâches perceptuelles et analysent les décisions en utilisant la théorie de la détection du signal pour étudier l'arbitrage optimalité-exactitude. Le premier essai confirme l'existence d'un tel arbitrage avec un rôle dominant de la recherche de l'exactitude. Il explique l'existence de cet arbitrage par utilité non-monétaire associée au fait d'avoir raison. Le deuxième chapitre montre que présenter les informations perceptuelles en dernier contribue à l'existence de l'arbitrage optimalité-exactitude.Le troisième essai étudie comment les préférences vie-à-vie d'autrui interagissent avec l'attitude face à l'ambiguïté. Il présente les résultats d'une expérience où les sujets doivent faire des dons à des associations caritatives. Les dons peuvent avoir des coûts ou des bénéfices ambigus. Nous constatons que l'ambiguïté a pour effet de rendre les individus plus égoïstes. En d'autres termes, nous montrons que les individus utilisent l'ambiguïté comme une excuse pour ne pas donner. Ce comportement d’auto-justification est plus marqué pour les coûts ambigus que pour les avantages ambigus.Le quatrième essai examine la validité externe des mesures de préférence pour le risque en laboratoire en utilisant des décisions dans d'autres tâches expérimentales risquées et des décisions prisent sur en dehors du laboratoire. Nous constatons que les mesures de préférence pour le risque permettent d'expliquer les premières, mais qu'elles n'expliquent pas les secondes
This thesis investigates how individuals make decisions under risk and uncertainty. It is composed of four essays that theoretically and experimentally investigate decision-making.The first two essays study situations where a decision maker has to decide whether an event has occurred using uncertain evidence. Accurately identifying that this event has occurred is more rewarded than accurately identifying that it has not occurred. This decision problem induces a divergence between two qualities of a decision: optimality and accuracy. Both essays reproduce such situations in a laboratory experiment based on perceptual tasks and analyze behavior using Signal Detection Theory to study the optimality-accuracy trade-off. The first essay confirms the existence of the trade-off with a leading role of accuracy. It explains the trade-off by the concern of individuals for being right. The second chapter finds that presenting perceptual evidence last contributes to the existence of the optimality-accuracy trade-off.The third essay studies how other-regarding preferences interact with attitude toward ambiguity. It reports the results of an experiment where subjects have to make donations to charities. Donations may have either ambiguous costs or ambiguous benefits. We find that other-regarding preferences are decreased under ambiguity. In other terms, we highlight that individual use ambiguity has an excuse not to give. This excuse-driven behavior is stronger for ambiguous costs than ambiguous benefits.The fourth essay challenges the external validity of laboratory risk preference measures using behavior in experimental risk tasks and naturally occurring behavior under risk. We find that risk preference measures are related with the former but that they fail to explain the latter
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46

Dallaire, François. "Electric sensing zone signal behaviour in liquid aluminium." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61133.

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Metal cleanliness is a major concern of today's aluminium industry. The metal cleanliness is related to the number and size of nonmetallic inclusions suspended in the liquid metal. A sensor, submerged in a liquid metal bath, produces a characteristic electrical signal during the passage of a particle through its Electric Sensing Zone (ESZ). On-line analysis of these signals enable melt particle size distribution to the derived. The present study focuses on signals obtained during application of such a sensor to aluminium melts.
Both the sensor and the preprocessing stages of the signal are described. A mathematical model of the high pass filtering transfer function is developed in the time domain to predict its role in modifying the raw signal's transient waveforms.
Classes of signal transients are identified and described in anticipation of further development based on pattern recognition techniques. Signal behaviour description in specific situations are performed through the relative occurrence rates of each class of transient. Attention is directed towards extraction of information relative to, both the production of particle size distribution as well as for sensor control purposes.
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47

Vezenkov, Stoyan Raykov. "Pharmacological studies on the contribution of the neuropeptide proctolin to the cephalic control of singing behavior in grasshopper Chorthippus biguttulus (L. 1758)." Doctoral thesis, [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=974032557.

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48

Carneiro, Breno Tercio Santos. "Sincroniza??o dos ritmos de atividade motora e temperatura central ? disponibilidade de glicose em ratos." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17300.

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Made available in DSpace on 2014-12-17T15:36:59Z (GMT). No. of bitstreams: 1 BrenoTSC_DISSERT.pdf: 3046533 bytes, checksum: 8a10fc9b8e091299347bfd22993003fe (MD5) Previous issue date: 2010-08-10
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Food is essential for the survival of all animals. Its temporal availability is an important enviromental cue for the behavioral and physiological organization throughout the 24 hours of day in different species. Rats and mice, for example, show increased locomotion in the hours before food availability when it is presented in a recurrent manner, a behavior named foodanticipatory activity. Several lines of evidence indicate that this anticipation is mediated by a circadian oscillator. In this work, based on the hypothesis that pre- or post-ingestive humoral signals are involved in the entrainment process, we tested whether the daily intake of glucose is sufficient to induce anticipatory activity in rats. The rhythms of motor activity and central temperature were recorded in animals undergoing 10 days of temporal glucose (solution at 50%) or chow restriction in light-dark (LD) and constant darkness (DD). Animals under temporal glucose restriction increase motor activity and and central temperature in the hours preceding glucose availability and such aticipation is extremely similar to that observed in animals under temporal chow restriction. Glucose ingestion is, therefore, a sufficient temporal cue to induce anticipation in rats. It is possible that the increase in plasma glucose after food ingestion constitutes one of the signals involved in the behavioral entrainment process to food availability
O alimento ? essencial para a sobreviv?ncia de todos os animais. Sua disponibilidade temporal ? uma pista ambiental importante para a organiza??o comportamental e fisiol?gica ao longo das 24 horas do dia em diferentes esp?cies. Ratos e camundongos, por exemplo, mostram aumento da locomo??o nas horas que antecedem a disponibilidade de alimento quando este ? apresentado de forma recorrente, um comportamento denominado de atividade antecipat?ria ao alimento. V?rias evid?ncias indicam que esta antecipa??o ? mediada por um oscilador circadiano. Neste trabalho, com base na hip?tese de que sinais humorais pr?- ou p?s-ingestivos est?o envolvidos no processo de sincroniza??o, testamos se a ingest?o di?ria de glicose ? suficiente para induzir atividade antecipat?ria em ratos. Os ritmos de atividade motora e temperatura central foram registrados em animais submetidos a 10 dias de restri??o de glicose (solu??o a 50 %) ou ra??o em claro-escuro (CE) 12h:12h e escuro constante (EE). Animais submetidos ? restri??o temporal de glicose mostram aumento da atividade motora e da temperatura central nas horas que antecedem a disponibilidade de glicose e tal antecipa??o ? extremamente semelhante ?quela observada em animais sob restri??o temporal de ra??o. A ingest?o de glicose ?, portanto, uma pista temporal suficiente para induzir antecipa??o em ratos. ? poss?vel que o aumento na concentra??o plasm?tica de glicose ap?s a ingest?o de alimento constitua um dos sinais envolvidos no processo de sincroniza??o comportamental ? disponibilidade de alimento
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49

Shariat, Yazdi Ramin. "Mixed signal design flow, a mixed signal PLL case study." Thesis, University of Waterloo, 2001. http://hdl.handle.net/10012/916.

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Mixed-signal designs are becoming more and more complex every day. In order to adapt to the new market requirements, a formal process for design and verification of mixed signal systems i. e. top-down design and bottom-up verification methodology is required. This methodology has already been established for digital design. The goal of this research is to propose a new design methodology for mixed signal systems. In the first two chapters of this thesis, the need for a mixed signal design flow based on top-down design methodology will be discussed. The proposed design flow is based on behavioral modeling of the mixed signal system using one of the mixed signal behavioral modeling languages. These models can be used for design and verification through different steps of the design from system level modeling to final physical design. The other advantage of the proposed flow is analog and digital co-design. In the remaining chapters of this thesis, the proposed design flow was verified by designing an 800 MHz mixed signal PLL. The PLL uses a charge pump phase frequency detector, a single capacitor loop filter, and a feed forward error correction architecture using an active damping control circuit instead of passive resistor in loop filter. The design was done in 0. 18- µ m CMOS process technology.
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50

Sheehan, Kevin Michael. "Evolving analogue electronic signal processing circuit behaviour in hardware." Thesis, Royal Holloway, University of London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272073.

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