published_or_final_version / Architecture / Master / Master of Architecture

Thesis (M. Sc.)--University of Hong Kong, 1997. / Cover title. Includes bibliographical references (leaf 138-139).

Thesis (M.B.A.)--University of Hong Kong, 1995. / Includes bibliographical references (leaves 78-81).

Thesis (Ph. D.)--Rutgers University, 2007. / "Graduate Program in Civil and Environmental Engineering." Includes bibliographical references (p. 194-200).

Στο κεντρικό νευρικό σύστημα υπάρχουν διακριτές περιοχές με αμιγώς αισθητική λειτουργία κι άλλες με αμιγώς κινητική. Υπάρχουν ωστόσο και περιοχές, των οποίων η λειτουργία είναι να συντονίζουν ολόκληρο το νευρικό σύστημα. Σημαντικό ρόλο σε αυτόν το συντονισμό έχουν οι χολινεργικοί και οι μονοαμινεργικοί νευρώνες, οι οποίοι με τους νευροδιαβιβαστές που εκκρίνουν, μπορούν να ελέγχουν μερικές από τις πιο περίπλοκες λειτουργίες του ΚΝΣ (μνήμη, δραστηριοποίηση, διάθεση, libido και πολλές άλλες). Η Ρ4 είναι μια πρωτεΐνη που ανακαλύφθηκε μόλις το 2004. Ανήκει στην οικογένεια των μεταφορέων SLC10 και μοιράζεται αρκετά κοινή δομή με τα υπόλοιπα μέλη, παρόλο που εκφράζεται σε εντελώς διαφορετικές περιοχές από αυτά. Η μοναδικότητα της Ρ4 έγκειται στο ότι είναι ένας διαμεμβρανικός νευροδιαβιβαστής που εντοπίζεται τόσο στους χολινεργικούς όσο και στους μονοαμινεργικούς νευρώνες, γεγονός που την καθιστά τον μόνο διαβιβαστή με διτή παρουσία και στα δύο αυτά συστήματα. Ωστόσο, δεν υπάρχουν ακόμη πολλές πληροφορίες για τον ακριβή εντοπισμό της σε αυτούς τους νευρώνες ούτε για το μήνυμα το οποίο μεταφέρει. Προηγούμενα πειράματα έδειξαν ότι η Ρ4 σχετίζεται με τον έλεγχο στην έκκριση της ντοπαμίνης. Η αρχική μας υπόθεση είναι ότι αυτό επιτυγχάνεται μέσω κάποιας αλληλεπίδρασης της Ρ4 και της VMAT2, η οποία είναι υπεύθυνη για την απελευθέρωση ντοπαμίνης από τα συναπτικά κυστίδια. Μια τέτοια σχέση, θα μπορούσε να δικαιολογηθεί αν οι δύο αυτές πρωτεΐνες εντοπίζονται στο ίδιο συναπτικό κυστίδιο. Προκειμένου να επαληθεύσουμε αυτήν την υπόθεση, χρησιμοποιήσαμε τη μέθοδο της Ανοσοκατακρήμνησης. Τα αποτελέσματα μέχρι στιγμής είναι ενθαρρυντικά και με μερικές βελτιστοποιήσεις, η μέθοδος αυτή θα μπορούσε να επαληθεύσει αυτήν την υπόθεση. Προκειμένου να διερευνηθεί περαιτέρω η λειτουργία της Ρ4, μελέτες συμπεριφοράς καθώς και φαρμακολογικές μελέτες πραγματοποιήθηκαν σε γενετικά τροποποιημένα ποντίκια, τα οποία δεν μπορούν να συνθέσουν Ρ4. Τα αποτέλεσματα έδειξαν ότι η Ρ4 δεν επηρεάζει τη λειτουργία της μνήμης, ωστόσο ίσως σχετίζεται με την ανάληψη πρωτοβουλίας και την επιθυμία ανταμοιβής. Παράλληλα, οι δοκιμές με αμφεταμίνη επαλήθευσαν ότι η Ρ4 σχετίζεται με την έκκριση ντοπαμίνης. Μελέτες με φλουοξετίνη έδειξαν πιθανή επίδραση της P4 στην έκκριση σεροτονίνης, η οποία ωστόσο δεν ήταν αρκετά ξεκάθαρη προς το παρόν. Τα πειράματα αυτά αποκάλυψαν ακόμη παράγοντες οι οποίοι μπορούν να επηρεάσουν την έκβαση των δοκιμών σε γενετικά τροποποιημένα ποντίκια και οι οποίοι θα πρέπει να λαμβάνονται υπόψη κατά το σχεδιασμό μελλοντικών πειραμάτων. Οι ιδιότητες της Ρ4 δεν έχουν κατανοηθεί ακόμα πλήρως και απαιτούνται πολλά επιπλέον πειράματα προκειμένου αυτές να αποκαλυφθούν. Νέες φαρμακολογικές μελέτες έχουν ήδη σχεδιαστεί, ενώ παράλληλα σύγχρονες μοριακές τεχνικές έχουν επιστρατευθεί ώστε να ρίξουν φως στην ακριβή της τοποθεσία. / This master thesis summarizes the efforts to identify the location and the behavioural effect of P4, a recently discovered protein. P4 belongs to the family of sodium‐dependent bile acid transporters (SLC10), whose first two members are expressed in the gastrointestinal system. However, P4 itself shows a wide expression pattern in various areas of the Central Nervous System. According to electron microscopy, in situ and immunohistochemistry studies, P4 is expressed specifically in both the cholinergic and the monoaminergic terminals, two systems that are responsible for various neurologic and psychiatric disorders. Previous cocaine provocation in KO animals indicated a possible effect of P4 in the release of dopamine. Since VMAT2 is responsible for the transfer of dopamine into the synaptic vesicles, the relation between P4 and VMAT2 needs to become clear. Using Immunoprecipitation, we tried to distinguish if P4 and VMAT2 share the same synaptic vesicle. Moreover, studies in animal models were used in order to unravel the function of P4: the Radial Arm Maze assessment showed no influence of P4 on memory but a possible effect in the reward system, amphetamine provocation showed that KO animals are more affected by amphetamine, while fluoxetine provocation indicated a possible effect of P4 in serotoninergic neurons. Tests in animals with different genetic origin revealed several factors that can affect the final outcome of these studies (age, weight and housing). All this data will help us design our future studies and cast more light in the properties of P4.

Because existing models have their limitations, there is a significant need for a model to estimate demand for intercity bus services, especially in rural areas. The general objective of this research was to develop an intercity mode choice model that can be incorporated into a statewide travel demand model to estimate demand for rural intercity bus services. Four intercity transportation modes were considered in the study: automobile, bus, rail, and air. A stated preference survey was conducted of individuals across the state of North Dakota, and a mixed logit model was developed to estimate a mode choice model. Results from the mode choice model showed the significant impacts of individual, trip, and mode characteristics on choice of mode. Gender, age, income, disability, trip purpose, party size, travel time, travel cost, and access distance were all found to have significant impacts on mode choice, and traveler attitudes were also found to be important. The study demonstrated how the mode choice model can be incorporated into a statewide travel demand model, and intercity bus mode shares were estimated for origin-destination pairs within the state. Alternative scenarios were analyzed to show how mode shares would change under different conditions or service characteristics. This study was conducted in the largely rural state of North Dakota, but results could be transferable to other areas with similar geographic characteristics. / U.S. Department of Transportation (USDOT)

The current study investigated the task performance and subjective preference for two color displays with differing image generation technologies, the standard cathode ray tube shadow mask (CRT) display and the newer liquid crystal/cathode ray tube (LC/CRT) display. Six subjects performed three different information processing tasks using each of the two color display technologies and expressed their display preference via evaluation questionnaires. Ambient illumination measurements were obtained to determine preferred conditions for each display. A four-way factorial design was used to collect task performance data and ambient illumination preferences; performance data were collected as errors per unit task quantity for each of the task types. Subjective evaluations consisted of 20 five-interval bipolar adjective scales and a forced choice rating on eight display parameters. An analysis of variance procedure and post-hoc Newman-Keuls analyses were employed in the analyses of the performance and subjective bipolar adjective scale data; the forced choice rating scales were evaluated using the Sign Test. The task performance results indicate that neither display produced better task performance. The subjective data revealed mixed results; while the bipolar adjective scales indicate no differences between the two display technologies, the forced choice rating shows a preference for the LC/CRT display on some display parameters. A significant difference between the two displays was demonstrated for ambient illumination preferences; the LC/CRT was viewed in greater ambient illumination than the CRT display. / Master of Science

This dissertation examined the effects of display spatial luminance nonuniformities on operator performance and perception. The objectives of this research were to develop definitions of nonuniformity, develop accurate measurement techniques, determine acceptable levels of nonuniformities, and to develop a predictive model based on user performance data. Nonuniformities were described in terms of spatial frequency, amplitude, display luminance, gradient shape, and number of dimensions. Performance measures included a visual random search task and a subjective measure to determine users' perceptions of the nonuniformities. Results showed that users were able to perform the search task in the presence of appreciable nonuniformities. lt was concluded that current published recommendations for acceptable levels of nonuniformities are adequately specified. Results from the subjective task showed that users were sensitive to the presence of nonuniformities in terms of their perceptions of uniformity. Specifically, results showed that as spatial frequency increased, perceived uniformity ratings increased. That is, users rated nonuniformities to be less noticeable. As amplitude and display luminance increased, the users' ratings of perceived uniformity decreased; that is, they rated the display as being farther from a uniform field. There were no differences in impressions between a sine and triangle gradient shape, while a square gradient shape resulted in lower ratings of perceived uniformity. Few differences were attributed to the dimension (1-D versus 2- D) of the nonuniformity and results were inconclusive because dimension was confounded with the display luminance. Nonuniformities were analyzed using Fourier techniques to determine the amplitudes of the coefficients for each nonuniformity pattern. These physical descriptors were used to develop models to predict users' perceptions of the nonuniformities. A few models yielded good fits of the subjective data. lt was concluded that the method for describing and measuring nonuniformities was successful. Also, the results of this research were in strong concurrence with previous research in the area of spatial vision. / Ph. D.

published_or_final_version / Transport Policy and Planning / Master / Master of Arts

Thesis (MScEng (Industrial Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The purpose of this study is to investigate the capacity of a proposed bus rapid transit (BRT) station in Cape Town. A bus rapid transit system is a high-capacity public transportation system that carries passengers from one point to another, providing a service that is faster and more efficient than an ordinary bus line. The implementation of these systems is increasing rapidly worldwide, serving as a solution to decrease traffic congestion. The capacity of the proposed bus station, known as the Thibault Station, is investigated in the study by developing a simulation model. The aim is to develop a stochastic simulation model, which represents the flow of passengers throughout the station so that the station capacity can be investigated. By developing a stochastic model as opposed to a deterministic model, elements of uncertainty can be included into the model, thereby representing a system that is closer to the real-life situation under investigation. The majority of BRT systems, as well as past studies undertaken on the Thibault Station, are designed using deterministic calculations. The study commences by researching literature on BRT systems and focuses on the current methods used to calculate station capacity requirements. Thereafter, the concept of simulation is introduced. Simulation is the method chosen to model and evaluate the passenger and bus operations at the Thibault Station. The study presents the methods used to build and verify the simulation model. This is done to familiarise the user with a number of aspects of the model. The model can then be used as a tool to investigate capacity parameters and alternative designs or scenarios. Using the results of these investigations, decisions can ultimately be made regarding the planning and design components of any bus rapid transit station given that the model is adapted. Scenario results, as well as interpretations of performance measurements, are presented at the end of the study. The results can be used for more realistic design of BRT stations using stochastic modelling. / AFRIKAANSE OPSOMMING: Die doel van die studie is om ondersoek in te stel na die kapasiteit van „n hoëspoed bus vervoer stelsel (BRT). Die ondersoek is gebaseer op „n voorgestelde bus stelsel vir Kaapstad. „n BRT-stelsel is „n hoë-kapasiteit publieke vervoerstelsel wat passasiers van een punt na „n ander vervoer, deur „n diens te verskaf wat vinniger en meer doeltreffend is as „n gewone bus stelsel. Die implementering van hierdie tipe stelsels neem wêreldwyd toe en dien as „n oplossing om verkeersopeenhopings te verminder. Die spesifieke busstasie wat ondersoek word staan bekend as die Thibault Stasie van Kaapstad se BRT-stelsel. Die kapasiteit van die stasie word ondersoek deur middel van simulasiemodellering. Die doel is om „n stogastiese simulasiemodel wat die vloei van passasiers modelleer te ontwikkel ten einde die kapasiteit van die stasie te ondersoek. Deur „n stogastiese model in plaas van „n deterministiese model te gebruik, kan elemente van onsekerheid ingesluit word. Dit verteenwoordig dus „n stelsel wat nader aan die werklikheid is. Tans word meeste BRT-stelsels ontwerpe gebaseer op deterministiese berekeninge, asook historiese studies wat onderneem is oor die Thibault Stasie. Die studie begin deur literatuur oor BRT-stelsels te bestudeer en fokus daarna op die huidige metodes wat gebruik word om die vereiste kapasiteit van „n busstasie te bepaal. Die konsep van simulasie word daarna voorgestel. Simulasie is die metode wat in die studie gebruik word om die passasier- en busaktiwiteite van die Thibault Stasie te modelleer en te evalueer. Die studie verskaf die metodes wat gebruik word vir die ontwikkeling en geldigmaak van die simulasiemodel. Gebruikers word op dié manier blootgestel aan die verskillende aspekte van die model. Nadat die gebruikers vertroud is met sekere aspekte van die model, word die model verder uiteengesit en word daar verduidelik hoe dit as „n instrument om kapasiteit parameters en alternatiewe ontwerpe van busstasies te ondersoek kan dien. Die resultate van die model kan gebruik word om beplannings- en ontwerpbesluite van enige busstasie te neem. Aan die einde van die studie word scenarioresultate bekendgestel, asook die interpretasie daarvan. Die resultate kan gebruik word vir meer realistiese ontwerp van BRT-stasies met behulp van stogastiese simulasie modellering.