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Eye movements under the control of working memory : the challenge of a reading-span taskGendt, Anja January 2011 (has links)
During reading oculomotor processes guide the eyes over the text. The visual information recorded is accessed, evaluated and processed. Only by retrieving the meaning of a word from the long-term memory, as well as through the connection and storage of the information about each individual word, is it possible to access the semantic meaning of a sentence. Therefore memory, and here in particular working memory, plays a pivotal role in the basic processes of reading. The following dissertation investigates to what extent different demands on memory and memory capacity have an effect on eye movement behavior while reading. The frequently used paradigm of the reading span task, in which test subjects read and evaluate individual sentences, was used for the experimental review of the research questions. The results speak for the fact that working memory processes have a direct effect on various eye movement measurements. Thus a high working memory load, for example, reduced the perceptual span while reading. The lower the individual working memory capacity of the reader was, the stronger was the influence of the working memory load on the processing of the sentence. / Beim Lesen steuern okulomotorische Prozesse die Blickbewegungen über den Text. Die aufgenommenen visuellen Informationen werden erschlossen, beurteilt und verarbeitet. Erst durch den Abruf der Wortbedeutung aus dem Langzeitgedächtnis, und die Verknüpfung sowie Speicherung der einzelnen Wortinformationen erschließt sich die semantische Bedeutung eines Satzes. Somit stellt das Gedächtnis und hier insbesondere das Arbeitsgedächtnis eines der grundlegenden Prozesse für das Lesen dar. Die vorliegende Dissertation untersucht inwieweit sich unterschiedliche Gedächtnisanforderungen und Gedächtniskapazitäten auf das Blickverhalten während des Lesens auswirken. Für die experimentelle Überprüfung der Forschungsfragen wurde das in der Arbeitsgedächtnisforschung sehr häufig genutzte Paradigma der Lesespannenaufgabe verwendet, bei dem Probanden einzelne Sätze lesen und beurteilen. Die Ergebnisse sprechen für einen direkten Einfluss von Arbeitsgedächtnisprozessen auf verschiedene Blickbewegungsmaße. So reduzierte eine hohe Arbeitsgedächtnisbelastung beispielsweise die perzeptuelle Spanne während des Lesens. Je geringer die individuelle Arbeitsgedächtniskapazität des Lesers war, desto stärker war der Einfluss der Arbeitsgedächtnisbelastung auf die Satzverarbeitung.
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Hur påverkas arbetsmotivationen av åldrande? : En kvantitativ studie om skillnader i arbetsmotivation mellan åldersgrupper / How does ageing affect motivation for work? : A quantitative cross-sectional study of different age groupsJohansson, Amadeus, Magnusson, Henrik January 2015 (has links)
Syftet med denna studie är att undersöka skillnader mellan vad som motiverar olika åldersgrupper i arbetslivet. Studiens hypoteser bygger på tidigare forskning som visade att betydelsen av interna motivationsfaktorer ökar med ålder, samt att betydelsen av externa faktorer minskar. Studien genomfördes på en multinationell logistikorganisation i mars 2015 genom en kvantitativ enkätundersökning på 119 deltagare. Reliabilitetstest för studien visade på god reliabilitet för både externa faktorer (α=0,85) och interna faktorer (α=0,79). Korrelations- och variansanalyser genomfördes för att analysera data. En signifikansnivå på p=0,05 användes och resultatet visade att betydelsen av de externa faktorerna lön, karriärmöjligheter, status, beröm och auktoritet minskade med ökad ålder, samt att betydelsen av de interna faktorerna tillhörighet, egen prestation, flexibilitet, självständighet, intresse och utmaningar ökade med ålder. Samtliga nämnda motivationsfaktorer var signifikanta och hade en signifikansnivå mellan p=0,000 och p=0,019. Denna studie kastar därmed ljus på hur individers åldrande leder till att betydelsen av externa motivationsfaktorer förskjuts till en ökad betydelse av interna motivationsfaktorer.
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Design and Analysis of Cryptographic Pseudorandom Number/Sequence Generators with Applications in RFIDMandal, Kalikinkar 15 August 2013 (has links)
This thesis is concerned with the design and analysis of strong de Bruijn sequences and span n sequences, and nonlinear feedback shift register (NLFSR) based pseudorandom number generators for radio frequency identification (RFID) tags. We study the generation of span n sequences using structured searching in which an NLFSR with a class of feedback functions is employed to find span n sequences. Some properties of the recurrence relation for the structured search are discovered. We use five classes of functions in this structured search, and present the number of span n sequences for 6 <= n <= 20. The linear span of a new span n sequence lies between near-optimal and optimal. According to our empirical studies, a span n sequence can be found in the structured search with a better probability of success. Newly found span n sequences can be used in the composited construction and in designing lightweight pseudorandom number generators.
We first refine the composited construction based on a span n sequence for generating long de Bruijn sequences. A de Bruijn sequence produced by the composited construction is referred to as a composited de Bruijn sequence. The linear complexity of a composited de Bruijn sequence is determined. We analyze the feedback function of the composited construction from an approximation point of view for producing strong de Bruijn sequences. The cycle structure of an approximated feedback function and the linear complexity of a sequence produced by an approximated feedback function are determined. A few examples of strong de Bruijn sequences with the implementation issues of the feedback functions of an (n+16)-stage NLFSR are presented.
We propose a new lightweight pseudorandom number generator family, named Warbler family based on NLFSRs for smart devices. Warbler family is comprised of a combination of modified de Bruijn blocks (CMDB) and a nonlinear feedback Welch-Gong (WG) generator. We derive the randomness properties such as period and linear complexity of an output sequence produced by the Warbler family. Two instances, Warbler-I and Warbler-II, of the Warbler family are proposed for passive RFID tags. The CMDBs of both Warbler-I and Warbler-II contain span n sequences that are produced by the structured search. We analyze the security properties of Warbler-I and Warbler-II by considering the statistical tests and several cryptanalytic attacks. Hardware implementations of both instances in VHDL show that Warbler-I and Warbler-II require 46 slices and 58 slices, respectively. Warbler-I can be used to generate 16-bit random numbers in the tag identification protocol of the EPC Class 1 Generation 2 standard, and Warbler-II can be employed as a random number generator in the tag identification as well as an authentication protocol for RFID systems.
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Optimization of Span-to-depth Ratios in High-strength Concrete Girder BridgesPoon, Sandy Shuk-Yan 16 February 2010 (has links)
Span-to-depth ratio is an important bridge design parameter that affects structural behaviour, construction costs and aesthetics. A study of 86 constant-depth girders indicates that conventional ratios have not changed significantly since 1958. These conventional ratios are now questionable, because recently developed high-strength concrete has enhanced mechanical properties that allow for slenderer sections.
Based on material consumption, cost, and aesthetics comparisons, the thesis determines optimal ratios of an 8-span highway viaduct constructed with high-strength concrete. Three bridge types are investigated: cast-in-place on falsework box-girder and solid slabs, and precast segmental span-by-span box-girder. Results demonstrate that total construction cost is relatively insensitive to span-to-depth ratio over the following ranges of ratios: 10-35, 30-45, and 15-25 for the three bridge types respectively. This finding leads to greater freedom for aesthetic expressions because, compared to conventional values (i.e. 18-23, 22-39, and 16-19), higher ranges of ratios can now be selected without significant cost premiums.
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Bridge System with Precast Concrete Double-T Girder and External Unbonded Post-tensioningLi, Yang Eileen 06 April 2010 (has links)
This thesis compares the consumption of primary superstructure material in a conventional single span CPCI system with those of double-T alternatives. The CPCI system is currently the preferred bridge type for short and medium spans in Canada, despite its relatively inefficient use of materials due to imperfect live load sharing among multiple parallel girders. The double-T alternatives utilize slender double-T cross-sections, fully precast segments, and post-tensioning in both longitudinal and transverse direction.
The economy of the CPCI and double-T systems is compared within the framework of four sample designs. The results indicate that the double-T systems are in general more efficient than the CPCI system and have the potential to achieve better economy.
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Life Histories of Women in CoachingMcCharles, Beth Lynne 21 April 2010 (has links)
The Canadian sport system is challenged by the lack of representation of female leaders and coaches. This is, in spite of statistics showing that female athletes account for almost half of all participants in sport, a number that is still growing (Sport Canada, 1999). Women have acquired equity in many areas of life and are accepted in leadership roles, however in the area of sport, women have yet to gain the full credibility and professional respect equal to their male counterparts. Previous research indicates that women who pursue a career in coaching face many adversities and struggle to attain a level of leadership where they can achieve their highest potential (Acosta & Carpenter, 2002). The purpose of this research is to gain an understanding of the lived experiences of elite female coaches, using Erikson’s (1950) theory of psychosocial development. In this study, the qualitative method of life history was used to learn about the experiences of female coaches, specifically the process of becoming and being elite coaches. Five elite Canadian coaches were interviewed. The major themes that developed through the analysis of the interviews were: (a) Support, (b) Overcoming Obstacles, (c) Personal Qualities and (d) The Bigger Picture. The study noted the importance of various support systems through one’s lifespan and some of the challenges a female athlete and coach must overcome to become a successful athlete, coach and mother. The study shares insight into the five women’s personal qualities that helped them grow into elite coaches. Finally, the participants described the process by which they came to find a leadership style with which they were comfortable, as coaches and as women.
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Optimization of Span-to-depth Ratios in High-strength Concrete Girder BridgesPoon, Sandy Shuk-Yan 16 February 2010 (has links)
Span-to-depth ratio is an important bridge design parameter that affects structural behaviour, construction costs and aesthetics. A study of 86 constant-depth girders indicates that conventional ratios have not changed significantly since 1958. These conventional ratios are now questionable, because recently developed high-strength concrete has enhanced mechanical properties that allow for slenderer sections.
Based on material consumption, cost, and aesthetics comparisons, the thesis determines optimal ratios of an 8-span highway viaduct constructed with high-strength concrete. Three bridge types are investigated: cast-in-place on falsework box-girder and solid slabs, and precast segmental span-by-span box-girder. Results demonstrate that total construction cost is relatively insensitive to span-to-depth ratio over the following ranges of ratios: 10-35, 30-45, and 15-25 for the three bridge types respectively. This finding leads to greater freedom for aesthetic expressions because, compared to conventional values (i.e. 18-23, 22-39, and 16-19), higher ranges of ratios can now be selected without significant cost premiums.
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Bridge System with Precast Concrete Double-T Girder and External Unbonded Post-tensioningLi, Yang Eileen 06 April 2010 (has links)
This thesis compares the consumption of primary superstructure material in a conventional single span CPCI system with those of double-T alternatives. The CPCI system is currently the preferred bridge type for short and medium spans in Canada, despite its relatively inefficient use of materials due to imperfect live load sharing among multiple parallel girders. The double-T alternatives utilize slender double-T cross-sections, fully precast segments, and post-tensioning in both longitudinal and transverse direction.
The economy of the CPCI and double-T systems is compared within the framework of four sample designs. The results indicate that the double-T systems are in general more efficient than the CPCI system and have the potential to achieve better economy.
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The Performance Of Medium And Long Span Timber Roof Structures: A Comparative Study Between Structural Timber And SteelErtastan, Evren 01 December 2005 (has links) (PDF)
ABSTRACT
THE PERFORMANCE OF MEDIUM AND LONG SPAN TIMBER ROOF STRUCTURES: A COMPARATIVE STUDY BETWEEN STRUCTURAL TIMBER AND STEEL
ERTASTAN, Evren
M.S, in Building Science,
Department of Architecture
Supervisor: Assoc. Prof. Dr. Ercü / ment ERMAN
December 2005, 174 pages
This thesis analyzes the performance of structural timber and steel in medium and long span roof structures. A technical background about roof structures including structural elements and roof structure types, span definitions, and classification of roof structures are discussed. Roof structures are detailed with traditional and the contemporary forms. The thesis comprises the comparison between structural timber and steel by using structural, constructional and material properties. Structural forms and the performance of timber and steel are discussed. The research also includes the roof structures built with structural timber in Turkey, application, marketing and examples in Turkey are indicated. In the conclusion part the performance criteria of timber and steel are summarized, the researcher has prepared a table to compare the performance of timber and steel.
Keywords: Timber, Steel, Roof, Structure, Span
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Factors affecting the continuation of elderly people in a volunteering service /Li, Yuen-wah, Cecilla. January 1997 (has links)
Thesis (M. Soc. Sc.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 81-84).
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