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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
481

The Constituents of Action Representation Evoked When Identifying Manipulable Objects

Lin, Yu-Tang Terry 08 May 2014 (has links)
We examined the effects of keeping hand actions in working memory on the speed of naming handled objects. The features of the hand action and objects’ handle matched or mismatched on two dimensions: alignment (left vs. right), orientation (horizontal vs. vertical). For objects presented in their canonical upright position, the speed of naming was only slower when the actions were partially incongruent with the target object. For rotated objects, the effect was reversed. The pattern of results suggests that the identification system is more sensitive to the functional goal (i.e. the end state) of the rotated object in evoking action representations than the actions evoked by the depicted view (i.e. the beginning state). The findings, overall, strongly support the notion that action representations play a functional role in object identification. / Graduate / 0633 / 0623 / tlin23@gmail.com
482

Development of a Method for GC/MS Analysis of PAHs and Alkylated PAHs for Use in Characterization and Source Identification of PAH Contaminated Sites

Vestlund, Hanne January 2014 (has links)
Polycyclic aromatic hydrocarbons (PAHs) are toxic and carcinogenic environmental contaminants originating from different sources; petrogenic, pyrogenic or biogenic. Depending on the source of contamination there will be different ratios of PAHs and the effects on the environment will differ. Petrogenic sources will be higher in concentration of alkyl substituted PAHs (APAHs) while pyrogenic sources will be higher in parent PAHs. In the present study a GC/MS method was developed to separate and calibrate PAHs, dibenzothiophenes and alkyl substituted PAHs in a mix containing 49 standards. The method was able to differentiate between PAHs and APAHs with the same mass number; up to six different compounds with the same mass number was separated. The developed method was used to analyse six different soil samples from various contamination sites. PAHs, APAHs and dibenzothiophenes were identified and quantified in all samples. In order to establish the source of contamination, the distribution pattern, the ratio between different PAHs, and the ratio between APAHs and parent PAHs were used. There was a higher ratio of APAHs/PAHs and a lower ratio between the parent PAHs in the soil samples from sites contaminated with oils compared to the other samples, indicating petrogenic source. / Polycykliska aromatiska kolväten (PAH) är giftiga och cancerframkallande miljögifter som härstammar från olika källor; petrogena, pyrogena eller biogena. Olika föroreningskällor kommer att ha olika förhållanden av PAH och effekterna på miljön kommer att skilja. Petrogena källor innehåller högre koncentrationer av alkylsubstituerade PAH (APAH) medan pyrogena källor kommer att ha högre koncentration av PAH. I denna studie har en GC/MS-metod utvecklats för att separera och kalibrera PAH, dibensotiofener och alkylsubstituerade PAH i en blandning innehållande 49 standarder. Metoden kunde skilja mellan PAH och alkylsubstituerade PAH med samma masstal; upp till sex olika föreningar med samma masstal särskildes. Den utvecklade metoden användes för att analysera sex olika jordprover från olika föroreningsplatser. PAH, APAH och dibensotiofener identifierades och kvantifieras i samtliga prover. För att fastställa föroreningskällan användes fördelningsmönstret för APAH och PAH, förhållandet mellan olika PAH och ration mellan APAH och PAH. Det fanns en högre kvot APAH/PAH i jordprover från områden som var förorenade med olja, vilket indikerar på petrogena föroreningskällor.
483

The Constituents of Action Representation Evoked When Identifying Manipulable Objects

Lin, Yu-Tang Terry 08 May 2014 (has links)
We examined the effects of keeping hand actions in working memory on the speed of naming handled objects. The features of the hand action and objects’ handle matched or mismatched on two dimensions: alignment (left vs. right), orientation (horizontal vs. vertical). For objects presented in their canonical upright position, the speed of naming was only slower when the actions were partially incongruent with the target object. For rotated objects, the effect was reversed. The pattern of results suggests that the identification system is more sensitive to the functional goal (i.e. the end state) of the rotated object in evoking action representations than the actions evoked by the depicted view (i.e. the beginning state). The findings, overall, strongly support the notion that action representations play a functional role in object identification. / Graduate / 0633 / 0623 / tlin23@gmail.com
484

Behaviour and personality in delinquent children

Shapland, Joanna January 1976 (has links)
The thesis is concerned with aspects of personality that may distinguish those children from a high delinquency area who become delinquent from those who do not. In Chapter 1 the limitations this approach places on the selection of the area and the sample to be studied are discussed. The two main methods of measuring criminality, convictions and self-report delinquency, are compared as to their usefulness for the study. The theoretical background for the choice of the personality variables to be considered is given. Two of these, susceptibility to reward and susceptibility to punishment, derive from operant conditioning tasks in which the subject presses a lever to obtain reward. Tests possibly measuring susceptibility to reward were stimulus generalization (from an intradimensional discrimination) and performance under differential reinforcement of low rates of response. In children, tests of susceptibility to punishment must be tests of susceptibility to frustrative nonreward (considered equivalent to punishment in its behavioural effects). In the present study the ones used were behavioural contrast on both extradimensional and intradimensional discriminations and a measure of peak shift. Questionnaire measures of extraversion, neuroticism and psychoticism were also used. The main hypothesis of the present study is that delinquents should be more susceptible to reward and less susceptible to punishment than nondelinquents. This may be tested in three ways: The first is to administer tests of susceptibility to reward and to purishment (the behavioural measures), and tests of delinquency (self-report delinquency) and to correlate the results of the two. The second is to correlate the scores of the children on tests of susceptibility to reward and to punishment and on personality questionnaires. The prediction (from Gray, 1973) is that susceptibility to reward should be correlated with extraversion and neuroticism and susceptibility to punishment with introversion and neuroticism. The third is to correlate delinquency scores with personality questionnaire scores, with the prediction that delinquents should be more extravert but not more neurotic than nondelinquents. All three ways are used in the present study. The total sample of the present study consisted of 54 school boys aged 11.1 to 12.9 years at the time of first testing, from a working-class housing estate. They were first given the personality questionnaires and delinquency tests (test administration). 31 boys (the behavioural sample) were selected from the total sample so that a full range of delinquency scores was obtained and given the behavioural tests of susceptibility to reward and to punishment. After this, the total sample was then given the personality questionnaires and delinquency tests again (retest administration). A study performed by Dr. J.P. Eushton on younger children aged 7 to 11 years was designed to run parallel with the present study. Comparisons are made with this study and with the previous work of Nicholson (1972) and de Wit (unpublished: described in Appendix C) throughout the thesis. Chapter 2 is concerned with the description of the personality questionnaires used and their reliability and intercorrelations. The questionnaires used were the Junior Eysenck Personality Inventory (JEPI), the High School Personality Questionnaire (HSPQ), the Junior Personality Questionnaire (JPQ) and a Teacher's Rating Scale (TRS: Nicholson, 1972), in which the form teachers of the boys rated the boys in their year. These give measures of extraversion, neuroticism, psychoticism and tendency to fake. Chapter 3 is concerned with the measurement of delinquency by the self-report method. A review of the rationale "behind the method and the various methodological problems encountered is given. It is also shown that delinquency is heterogeneous so that it is necessary to measure participation in various aspects of crime, for example, group versus solitary crime. The self-report interview used in the present study is described. This produces a measure of number of different types of crime committed and measures of involvement in group crime, solitary crime, self-suggested crime and other-suggested crime. The interview was shown to have high test-retest reliability and internal consistency. Principle components analysis produced a large first component, loading on all the delinquency items. Inconsistent responders between the test and retest administration of the interview were identified and inconsistent responding shown to relate positively to the JPQ, lie scale and negatively to number of crimes admitted. The third way of testing the main hypothesis, the correlations between personality and crime, is examined in Chapter 4. A review of the studies used to test Eysenck's theory of the relationship between personality and crime is given. Significant positive correlations of number of delinquent acts admitted with both extraversion and psychoticism were found. No such correlations were found with neuroticism. The hypotheses of Eysenck (1974) and Burgess (1972a) that the extravert neurotic quadrant should contain more criminals than other quadrants in the Eysenckian two-dimensional space was not supported. The behavioural measures and their correlations with the personality questionnaire scores and crime scores (the first and second ways of testing the main hypothesis) are discussed in Chapters 5 to 8. Chapter 5 deals with the phenomenon of behavioural contrast and its use to measure susceptibility to frustrative nonreward. A review of the animal and human literature is given, in which it is concluded that the frustration theory of behavioural contrast is the best currently available. The extra-dimensional and intradimensional discriminations of the present study are then described, together with possible controls for the behavioural contrast shown. Measures of the time taken to reach the baseline criterion, the time taken to be able to describe the discrimination conditions and the time then required to perform the discrimination to criterion were also used. The correlations with introversion and neuroticism found by Nicholson (1972) were not replicated with all the personality measures used in the present study. Chapter 6 discusses the phenomena occumng in the generalization test given after the intradimensional discrimination; peak shift, mean shift and stimulus generalization. A review of the animal and human literature on these phenomena is given. Mean shift, although shown by 18 out of 24 boys tested, was not found to be correlated with either introversion or neuroticism as found by Nicholson (1972). Stimulus generalization, however, did show some correlations with extraversion and neuroticism. Chapter 7 is concerned with the differential reinforcement of low rates of response tasks. A review of these tasks in am'mis and humans with regard to the use of a series of progressively more difficult tasks in measuring susceptibility to reward is given. The results of the present studies tend to indicate that the first task in the series correlates with developmental measures such as age, whereas the second and third tasks correlate more with the personality measures, notably extraversion and neuroticism. The third task (and, in the present study, the second task) may hence be used as a measure of susceptibility to reward. Chapter 8 discusses the correlations between all the measures taken. The two measures of susceptibility to reward show some moderate positive correlations.
485

Predicting social identity and the impact of typicality of group membership

Barlow, Kelly M. January 1998 (has links)
Des etudes anterieures ont ete incapbles de determiner quels facteurs sous-tendent l'identite sociale. A l'aide de plusieurs innovations methodologiques (une mesure permettant d'exprimer librement les facteurs relies a l'identite sociale, le fait de choisir l'endogroupe et l'exogroupe et une conceptualisation de l'identite sociale comme etant composee de l'attirance envers l'endogroupe et du rejet par l'exogroupe), cette etude avait pour but d'etudier l'influence des trois facteurs postules par Tajfel (cognition, emotions et evaluation) et les croyances symboliques (coutumes, valeurs et normes) sur l'identite sociale. Les resultats de cette etude indiquent qu'une evaluation positive de l'endogroupe, les emotions positives envers l'endogroupe et une evaluation negative de l'exogroupe menacant sont associees a une identification sociale plus forte. De plus, les resultats de cette etude demontrent qu'une difference individuelle (A quel point vous percevez-vous comme un membre typique de votre groupe?) est associee a des facteurs relies a l'endogroupe (une identification plus forte et une integration du concept de soi plus eleve) et a l'exogroupe (menace intergroupe, discrimination personnelle et collective).
486

Model predictive control of a thermoelectric-based heat pump.

Petryna, Stephen 01 December 2013 (has links)
Government regulations and growing concerns regarding global warming has lead to an increasing number of passenger vehicles on the roads today that are not powered by the conventional internal combustion (IC) engine. Automotive manufacturers have introduced electric powertrains over the last 10 years which have introduced new challenges regarding powering accessory loads historically reliant on the mechanical energy of the IC engine. High density batteries are used to store the electrical energy required by an electric powertrain and due to their relatively narrow acceptable temperature range, require liquid cooling. The cooling system in place currently utilizes the A/C compressor for cooling and a separate electric element for heating which is energy expensive when the source of energy is electricity. The proposed solution is a thermoelectric heat pump for both heating and cooling. A model predictive controller (MPC) is designed, implemented and tested to optimize the operation of the thermoelectric heat pump. The model predictive controller is chosen due to its ability to accept multiple constrained inputs and outputs as well as optimize the system according to a cost function which may consist of any parameters the designer chooses. The system is highly non-linear and complex therefore both physical modelling and system identi cation were used to derive an accurate model of the system. A steepest descent algorithm was used for optimization of the cost function. The controller was tested in a test bench environment. The results show the thermoelectric heat pump does hold the battery at the speci ed set point however more optimization was expected from the controller. The controller fell short of expectation due to operational restriction enforced during design meant to simplify the problem. The MPC controller is capable of much better performance through adding more detail to the model, an improved optimization algorithm and allowing more flexibility in set point selection.
487

Next Generation RFID Randomization Protocol

LaValley, Jason 06 December 2011 (has links)
Radio Frequency IDentification (RFID) is a wireless communications technology which allows companies to secure their assets and increase the portability of information. This research was motivated by the increased commercial use of RFID technology. Existing security protocols with high levels of security have high computation requirements, and less intensive protocols can allow a tag to be tracked. The techniques proposed in this thesis result in the increase of ciphertexts available without a significant increase in processing power or storage requirements. The addition of random inputs to the generation of ciphertexts will increase the number of possible results without requiring a more advanced encryption algorithm or an increased number of stored encryption keys. Four methods of altering the plaintext/ciphertext pair (random block, set pattern, random pattern, and indexed placement) are analyzed to determine the effectiveness of each method. The number of ciphertexts generated, generation time, and generation errors were recorded to determine which of the four proposed methods would be the most beneficial in a RFID system. The comparison of these method characteristics determined that the set pattern placement method provided the best solution. The thesis also discusses how RFID transmissions appear to attackers and explains how the random inputs reduce effectiveness of current system attacks. In addition to improving the anonymity of RFID tag transmissions, the concept of authenticating random inputs is also introduced in this thesis. These methods help prevent an adversary from easily associating a tag with its transmissions, thus increasing the security of the RFID system.
488

Enhancing risk identification workshops: an idea generation approach

Sosa Silverio, Eduardo 06 1900 (has links)
Risk identification is the first step of risk management for construction projects. Project experts use many different methods to identify risk factors, such as decision trees, standard checklists, questionnaires and the Hazard and Operability procedure, but brainstorming sessions are among the most successful methods for identifying risks offering advantages not encountered in any of the others identification methods. Although the brainstorming technique is widespread in the construction industry, it typically is not used to its full capacity. This may be due to brainstorming literature ambiguity, variations in reporting technique usage in the literature, and lack of a methodology outlining the use of the brainstorming technique specifically for risk identification purposes. In this thesis, the merits, procedures, and appropriate applications of the brainstorming technique are outlined. Implications of the session, the session leader, the participants, and the output are explored, and best practices for risk identification brainstorming sessions are identified. / Construction Engineering and Management
489

Taxonomy and diagnostics of fruit fly infesting Opiine Braconids in Australia and the South Pacific

Carmichael, Amy Elizabeth January 2009 (has links)
Opiine wasps (Hymenoptera: Braconidae: Opiinae) are parasitoids of dacine fruit flies (Diptera: Tephritidae: Dacinae), the primary horticultural pests of Australia and the South Pacific. Effective use of opiines for biological control of fruit flies is limited by poor taxonomy and identification difficulties. To overcome these problems, this thesis had two aims: (i) to carry out traditional taxonomic research on the fruit fly infesting opine braconids of Australia and the South Pacific; and (ii) to transfer the results of the taxonomic research into user friendly diagnostic tools. Curated wasp material was borrowed from all major Australian museum collections holding specimens. This was supplemented by a large body of material gathered as part of a major fruit fly project in Papua New Guinea: nearly 4000 specimens were examined and identified. Each wasp species was illustrated using traditional scientific drawings, full colour photomicroscopy and scanning electron microscopy. An electronic identification key was developed using Lucid software and diagnostic images were loaded on the web-based Pest and Diseases Image Library (PaDIL). A taxonomic synopsis and distribution and host records for each of the 15 species of dacine-parasitising opiine braconids found in the South Pacific is presented. Biosteres illusorius Fischer (1971) was formally transferred to the genus Fopius and a new species, Fopius ferrari Carmichael and Wharton (2005), was described. Other species dealt with were Diachasmimorpha hageni (Fullaway, 1952), D. kraussii (Fullaway, 1951), D. longicaudata (Ashmead, 1905), D. tryoni (Cameron, 1911), Fopius arisanus (Sonan, 1932), F. deeralensis (Fullaway, 1950), F. schlingeri Wharton (1999), Opius froggatti Fullaway (195), Psyttalia fijiensis (Fullaway, 1936), P. muesebecki (Fischer, 1963), P. novaguineensis (Szépliget, 1900i) and Utetes perkinsi (Fullaway, 1950). This taxonomic component of the thesis has been formally published in the scientific literature. An interactive diagnostics package (“OpiineID”) was developed, the centre of which is a Lucid based multi-access key. Because the diagnostics package is computer based, without the space limitations of the journal publication, there is no pictorial limit in OpiineID and so it is comprehensively illustrated with SEM photographs, full colour photographs, line drawings and fully rendered illustrations. The identification key is only one small component of OpiineID and the key is supported by fact sheets with morphological descriptions, host associations, geographical information and images. Each species contained within the OpiineID package has also been uploaded onto the PaDIL website (www.padil.gov.au). Because the identification of fruit fly parasitoids is largely of concern to fruit fly workers, rather than braconid specialists, this thesis deals directly with an area of growing importance to many areas of pure and applied biology; the nexus between taxonomy and diagnostics. The Discussion chapter focuses on this area, particularly the opportunities offered by new communication and information tools as new ways delivering the outputs of taxonomic science.
490

Arbuscular mycorrhizal community in a permanent pasture and development of species-specific primers for detection and quantification of two AM fungi / Zaida Ines Antoniolli.

Antoniolli, Zaida Ines January 1999 (has links)
Bibliography: leaves 138-160. / xii, 160 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The 152 species of mycorrhizal fungi can be difficult to identify and quantify because the taxonomy of these fungi is based on the description of spores, which is time consuming, requires considerable expertise and cannot be assumed to reflect the situation within the root. Few attempts have been made to identify the species which are present in roots. Several approaches have been identified in previous work and the development of sensitive molecular methods for identification and quantification of two species of arbuscular mycorrhizal (AM) fungi are described in this study. Mycorrhizal fungal communities were sampled in both natural and agricultural ecosystems at two sites in South Australia. The combination of spore identification from trap culture and field-collected soil promises to be an effective means to study diversity of AM fungi in a particular system. PCR primers for Glomus mosseae and Gigaspora margarita were designed from the internal transcribed spacer (ITS) sequences of field-collected spores, with the aim of providing tools for field diagnosis. / Thesis (Ph.D.)--University of Adelaide, Dept. of Soil and Water, 2000?

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