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Changes in size strongly influence organisms' ecological performances. For aquatic organisms, they can transition from viscosity- to inertia-dominated fluid regimes as they grow. Such transitions are often associated with changes in morphology, swimming speed and kinematics. Barnacles do not fit into this norm as they have two morphologically distinct planktonic larval phases that swim differently but are of comparable sizes and operate in the same fluid regime (Reynolds number 100–101). We quantified the hydrodynamics of the rocky intertidal stalked barnacle Capitulum mitella from the nauplius II to cyprid stage and examined how kinematics and size increases affect its swimming performance. Cyprids beat their appendages in a metachronal wave to swim faster, more smoothly, and with less backwards slip per beat cycle than did all naupliar stages. Micro-particle image velocimetry showed that cyprids generated trailing viscous vortex rings that pushed water backwards for propulsion, contrary to the nauplii's forward suction current for particle capture. Our observations highlight that zooplankton swimming performance can shift via morphological and kinematic modifications without a significant size increase. The divergence in ecological functions through ontogeny in barnacles and the removal of feeding requirement likely contributed to the evolution of the specialized, taxonomically unique cyprid phase.

The desire to gain knowledge about the quality and timing of construction projects delivered to clients has become an increased focus point in the field of construction management. Clients have expectations that are often based on their assumptions about the validity of making the learning curve theory applicable to construction projects. This research aims to determine what criteria need to be met for the learning curve theory to have some validity for construction projects. The results from the questionnaire survey, completed by professionals from the construction industry, show that several concepts were found to be of importance: project specifications, design, scope, budget, site management, planning, monitoring and controlling, and quality. If these concepts correspond between two projects, the chance of successfully applying the learning curve theory increases. Practical recommendations are made that highlight the concepts identified as critical for the successful application of the learning curve theory to construction projects, and that can be used by clients and contractors as a basis for negotiating project schedules. As deel van die evolusie in konstruksiebestuur het kennis van projekkwaliteit asook die tydsduur van konstruksieprojekte 'n groter noodsaaklikheid geword. Kliënte het verwagtinge wat dikwels gebaseer word op persoonlike aannames rondom die geldigheid van die leerkurweteorie en die toepaslikheid daarvan op konstruksieprojekte. Die doel van hierdie navorsing is om die projekkriteria te bepaal wat in plek moet wees om die geldigheid van die leerkurweteorie op konstruksieprojekte te bevorder. Die uitslag van die opnamevraelys, wat deur professionele persone in die konstruksiebedryf voltooi is, het getoon dat daar verskeie kriteria van belang is, naamlik: die projekspesifikasie, die ontwerp en omvang van die projek, die begroting, die bestuur van die konstruksiewerf, die beplanning, monitering en kontrole, asook die kwaliteitverwagtinge van die projek. Indien meerdere van hierdie kriteria tussen twee projekte ooreenstem, verhoog dit die kans dat die leerkurweteorie suksesvol van een projek na 'n ander toegepas kan word. Ter afsluiting word praktiese aanbevelings gemaak wat die belangrike kriteria uitlig wat nodig is vir die suksesvolle toepassing van die leerkurweteorie op konstruksieprojekte. Hierdie aanbevelings kan deur kliente en kontrakteurs gebruik word as n basis tydens die onderhandeling van projekskedules vir opkomende en soortgelyke projekte.

The Project Management Office (PMO) has been associated with organisational project management competence. However, there is a lack of empirical evidence to support this perception. This study examines the relationship of PMO maturity and the nine knowledge areas that describe Organisational Project Management (OPM) by collecting data from 129 PMO executives, staff, and project managers in South African Government Infrastructure Departments (SAGID) using a structured questionnaire. The results show that a PMO's 'strategic' maturity has the highest impact on all nine areas of OPM. It is thus recommended that public organisations need to accelerate the strategic maturity of their PMOs to benefit from them. Die projekbestuurkantoor word met organisatoriese projekbestuurbevoegdheid assosieer. Daar is egter min empiriese bewysstukke om hierdie persepsie te regverdig. Die verwantskap tussen die projekbestuurkantoor volwassenheid en die nege kundigheidsareas wat organisatoriese projekbestuur volgens die Project Management Institute (PMI) beskryf, word ondersoek deur inligting van 129 projekbestuurkantoor uitvoerende beamptes, personeel en projekbestuurders in die Suid-Afrikaanse Regering se Infrastruktuur Departemente te versamel met 'n gestruktureerde vraelys. Die resultate wys daarop dat die projekbestuurkantoor se strategiese volwassenheid die grootste invloed op al nege die kundigheidsareas het. Dit word dus aanbeveel dat publieke organisasies die strategiese volwassenheid van hul projekbestuurkantore versnel om sodoende die meeste baat daarby te vind.

Projects that fail, for whatever reason, can impact negatively on society, organisations, and other stakeholders. A number of researchers have identified various critical success factors (CSFs) that can influence the outcome and success of a project. This research therefore aims to determine the CSFs that influence various success measures of small- to medium-sized projects at a South African mining company, Exxaro Resources' Grootegeluk Coal Mine. Other objectives of this research include determining the extent of the impacts of these CSFs on the different success measures of a project. The investigation suggests that there are correlations among CSFs, and that certain factors impact the outcome of projects far more than others. This research finds that the single most important CSF for small- to medium-sized projects is the selection of a competent project manager. The competent project manager is characterised by a group of interrelated CSF factors: good leadership, commitment, and learning from past experiences. Based on the research results, other CSFs are discussed and explored in order for recommendations to be made on how this mining company, and possibly other organisations, can achieve greater project success. Mislukte projekte kan negatiewe impakte op die samelewing, organisasies en ander belanghebbendes hê. In die literatuur is daar reeds verskeie kritiese suksesfaktore geïdentifiseer wat die uitkoms en sukses van 'n projek kan beïnvloed. Hierdie navorsing mik daarna om die kritiese suksesfaktore wat verskeie suksesmaatstawwe van klein- tot mediumgrootte projekte by Exxaro Resources se Grootgeluk steenkoolmyn in Suid-Afrika beïnvloed. Nog 'n doelstellings van die studie sluit in die bepaal van die mate van die impak van hierdie kritiese suksesfaktore op die verskillende suksesmaatstawwe van 'n projek. Die ondersoek dui daarop dat daar korrelasies onder kritiese suksesfaktore bestaan en dat sekere faktore 'n baie groter invloed op die uitkoms van projekte het as ander. Die belangrikste kritiese suksesfaktor vir klein- tot mediumgrootte projekte is die aanstel van 'n bevoegde projekbestuurder. 'n Bevoegde projekbestuurder word gekenmerk deur etlike onderlinge kritiese suksesfaktore, naamlik goeie leierseienskappe, toewyding en ervaring. Ander kritiese suksesfaktore word op grond van hierdie studie bespreek en ondersoek om aanbevelings te maak oor hoe die mynboumaatskappy, en moontlik ander organisasies, verbeterde projek sukses kan behaal.

[ABSTRACT] Boundary layer has a diurnal variation of temperature near the ground with thickness variation ranging from hundreds of meters to a few kilometers. The dynamics of this layer can reveal the trapped pollutants related to atmosphere, climate, and human activities in urban areas of a city. In this paper, we present the first time a comprehensive result of tracking urban planetary boundary layer of Hong Kong (22.3N, 114.7E). The daily and seasonal variations of the mixing depth in the planetary layer over urban areas in Kowloon have been investigated using a ground-base Lidar station situated in the City University of Hong Kong to monitor relative aerosol concentration. The relationships between the aerosol profile, which is used to estimate the depth of the mixing layer, and the virtual potential temperature as well as relative humidity are examined. The Lidar observations and the radiosonde data obtained from the local meteorological station are in close agreement.

Past studies of performance management systems (PMS) have focused more on designing the framework and less on the effect it has on employees. Moreover, employees in developing countries may not be knowledgeable or familiar with PMS. This paper proposes two competing statistical models to examine the roles that supervisor support (SS) has in engineering organisations. It was found that SS is a mediator, but not a moderator, in the relationship between PMS and employee job satisfaction. In other words, SS partially explains why employees have positive perceptions of their jobs based on their evaluation of the current PMS; SS thus enhances the PMS in engineering organisations. Vorige studies van prestasiebestuurstelsels het op die ontwerp van die raamwerk, eerder as die effek daarvan op werknemers, gefokus. Verder is werknemers in ontwikkelende lande dikwels nie ingelig en vertroud met prestasiebestuurstelsels nie. Twee meedingende statistiese modelle om die rol van toesighouerondersteuning te ondersoek word voorgestel. Daar is gevind dat toesighouerondersteuning in die verhouding tussen prestasiebestuurstelsels en werksbevrediging 'n bemiddelaar eerder as 'n moderator is. Toesighouerondersteuning verduidelik dus hoekom werknemers positiewe persepsies van hulle werksgeleenthede koester, gegrond op hul evaluering van die huidige prestasiebestuurstelsel. Toesighouerondersteuning bevorder dus die prestasiebestuurstelsel in ingenieursfirmas.

Research in electronic controlled internal\ud combustion engines mainly focuses on improving performance\ud and lowering the emissions. Combustion performance depends\ud on the geometry of cylinders and on the design of all\ud mechanical parts, which are based on the laboratory\ud experimental research. Due to the limitations of the materials\ud used in the engine and the continuous high operating\ud temperature, engines function in either spark ignition or\ud charge ignition processes. Recent research on computer\ud controlled engines uses sensors and electronic actuators which\ud allows switching the engine operational mode between spark\ud ignition and charge ignition. Thus, this makes possible to mix\ud intake fuel compositions in order to give more choices to\ud consumers.\ud This study employs a neural network which is capable of\ud estimating fuel composition using the parameters of residual\ud gas. The simulation is based on a thermodynamic engine model\ud implemented in Matlab Simulink. The main advantages are the\ud capabilities of the model to 1) calculate the gas exchange as a\ud function of time in transient mode, and 2) to generate data for\ud the design control algorithms without the need of the engine\ud bed test environment to test various fuel compositions.

180 p. Virtual Reality (VR) technology opens up many new possibilities. Advances in VR technology especially in the field of 3D computer graphics modeling and animation techniques and faster computing power has enabled us to create increasingly realistic Virtual Environments (VE) and 3D virtual humans, animals and objects to inhabit these Virtual Environments. VR technology is being used in a variety of real-time application domains including architectural visualization, vehicle design and prototyping, entertainment, simulation and training, teleoperations, scientific visualization, engineering, education, medicine / non-invasive surgery, and cultural heritage. Innovative and intuitive interaction techniques and methods need to be developed and employed in these VR applications to further enhance the interactive experience of the user. This thesis presents a cultural heritage application utilizing VR technology to recreate a fully immersive 3D environment of a complex heritage structure specific to Singapore. MASTER OF ENGINEERING (SCE)