Dissertations / Theses on the topic 'Draugar'

This essay deals with the concept of 'soul' in beliefs among north germanic pagans. As it comes forth in written sources, this concept can easely be seen as an odd contradiction, since the concept of 'soul' after the demise of a person seems to split. There seems to exist both an idea of different realms for the dead, and a thought that the dead would 'live' on in their graves. Some researchers, i.e. Price (2002) and Kaliff (1997), think that the soul of the dead human according to Nordic pagan belief split apart in a way, that there was an idea of the human soul being made up of several aspects, each with its own goal an purpose. Five such aspects have been identified - a protective free-soul, a personification of the inviduals luck (and possibly part of his/her destiny), a physical body or an aspect of the soul abilitating shape shifting, a persons thoughts and goals and very essence, and finally the dead body 'living' on in the burial mound. An alternative interpretation (i.e. Ellis 1968) is that the different explanations of the future of the dead are results of different traditions, connected to geographically and/or chronologically fixed ideas, but that certain remnants of earlier traditions could remain even when a new view of the afterlife has taken over. I have chosen to discuss these different viewpoints by comparing them with each other and with later swedish folklore, that is documented and seemingly originating during christian times. By peeling off views and beliefs of known christian origin, suprisingly well preserved representations of presumably older (pagan) views of the 'soul' and and its aspects have been identified. Furthermore, representations of soul aspects not yet described in connection with nordic paganism, and still not traceable to christian views, have been found. The result of the essay is that the theory of several soul aspects in pre-christian or pagan nordic beliefs seems to hold up best. Even if there, without a doubt, to some degree existed local variations and even though no tradition remains unchanged over time, it still would seem that the influence of these factors cannot in full explain the observed variation in views on soul aspects in pre-christian viking age Norse religion.

The number of horses in Ireland had shown remarkable consistency from 1861 until just before 1951. Between the end of the Second World War and 1951 there was a rapid decrease in the number of working horses, and the rate of the decrease accelerated during the decade of the 1950s and the early 1960s. Throughout the 1960s popular emphasis was placed on mechanisation, as if there were no role for the horse as a working animal. Even the production of pleasure horses seems to have been initially regarded as of little value. The 1970s were a sad period for both light and heavy draught horses in County Cork, as in the rest of Ireland. With increased mechanisation, the market for heavy draught animals which had previously dominated transport in the city of Cork, came to an end. There was a great danger that the Irish Draught would soon become extinct, so the formation of the Irish Draught Horse Society in 1976 was of great importance for the development of the Irish Draught as a breed. In 1982 this society published the "Breed Standard and Guideline", the first time that an official standard had been published for an Irish Draught. Despite various schemes during the 1980s and 1990s designed to increase the number and improve the quality of the Irish Draught horse population, it is, at the beginning of the 21st Century, one of the world's endangered breeds.

Thesis (MScEng)--Stellenbosch University, 2007.<br>ENGLISH ABSTRACT: A natural draught wet-cooling tower (NDWCT) was modelled using the Merkel method with an improved energy equation as recommended by Kloppers and Kroger (2005a) - referred to as the Improved Merkel method. The improved energy equation is used for calculating the heat rejection rate of the tower and includes the energy associated with water evaporation. The sensitivity indexes of a NDWCT were calculated numerically with the Improved Merkel method model. It was found that the perfonnance of a NDWCT is most sensitive to the fill Merkel number. The "Natklos" fill test facility at Stellenbosch University was used to estimate typical uncertainties found in fill performance characteristics. The zeroth order uncertainty for the Merkel number and loss coefficient was calculated to be 0.2100 m-1 and 0.4248 m- 1 , respectively, while the first order uncertainty for the Merkel number and loss coefficient was calculated to be 0.1933 m- 1 and 0.2008 m-1 , respectively. ASME requires that the uncertainty in tower capability has to be less than 6 % for a NDWCT perfonnance test to be deemed ASME approved. Propagating typical measurement uncertainties found in NDWCT test standards and experimental data into the tower capability showed that the 6 % uncertainty limit imposed by ASME is unrealistic and too stringent. Performance curve generator (PCG) is a software package developed that generates NDWCT perfonnance curves. With these performance curves it is possible to easily and effectively adjust the off-design test results in order to detennine whether the NDWCT has met its guarantee or not.<br>AFRIKAANSE OPSOMMING: Die werksverrigting van 'n natuurlike trek nat koeltoring (NTNT) is gemodelleer deur gebruik te maak van die Merkel metode met 'n verbeterde energie vergelyking, soos aanbeveel deur Kloppers en Kroger (2005a) - Verbeterde Merkel metode. Die energie vergelyking word gebruik om die toring se tempo van warmteoordrag te bereken en sluit die energieverlies as gevolg van verdamping in. Die Verbeterde Merkel metode model was gebruik om die sensitiwiteits-indekse van 'n NTNT te bepaal. Die analise toon dat die toring se werksverrigting die sensitiefste is vir die pakking se Merkel getal. Die Natklos pakkingstoetsfasiliteit aan die Universiteit van Stellenbosch was gebruik om tipiese onsekerheid in die pakkingsprestasiekarakteristieke te bepaal. Die zero-orde onsekerheid in die Merkel getal en verlieskoeffisient was bereken as 0.2100 m· 1 en 0.4248 m· 1 , onderskeidelik, terwyl die eerste-orde onsekerhede bereken was as 0.1933 m·1 en 0.2008 m· 1 , onderskeidelik. Die toelaatbare onsekerheid in toringvennoe vir 'n NTNT aanvaardingstoes volgens ASME is 6 %. Deur tipes meetonsekerhede, soos gegee deur NTNT aanvaardings-toesstandaarde sowel as eksperimentele data, deur te propageer, word 'n onsekerheid veel groter as die toelaatbare 6 % gegenereer. 'n Renekaarpakket, genaamd Performance Curve Generator (PCG), is ontwikkel om werksverrigtinskurwes vir 'n NTNT te genereer. PCG se werksverrigtinskurwes maak dit moonltik om maklik te bepaal of a NTNT sy ontwerpskriterea bereik het of nie.

Thesis (PhD)--Stellenbosch University, 2011.<br>ENGLISH ABSTRACT: Axial flow fan arrays form part of air-cooled steam condensers in direct drycooled power plants. This dissertation investigates the performance of axial flow fans when located at the perimeter of a fan array. The perimeter (or edge) fans may experience a reduction in air flow through the fan due to the prevalence of distorted inlet conditions upstream of the fan. The reduction in air flow leads to a reduction in the heat transfer capability of the steam condenser and a consequent reduction in the electricity output of the power plant. Due to the physical size of an air-cooled condenser, full-scale experiments are often impractical and computational fluid dynamics (CFD) is used to model its performance under various conditions. To limit the size of the CFD model the axial flow fans in the CFD analysis are represented by means of simplified methods. Three different simplified methods are presented and applied to a CFD model of a single axial flow fan, namely the pressure jump method (PJM), actuator disc method (ADM) and extended actuator disc method (EADM). The results are compared to experimental values. The comparison highlights the limitations of the models: The ADM fails to model fan performance correctly at low flow rates, while the PJM ignores the variation in fan blade properties at different locations within the fan rotor. The EADM is presented as an improvement on both the other two models. A multiple fan test facility is constructed, consisting of three 630 mm diameter fans extracting air from a common inlet chamber. The inlet chamber is constructed in such a way that one of the three fans act as the perimeter (edge) fan. The floor of the inlet chamber can be adjusted to increase or reduce the inlet flow distortion experienced by the edge fan. Six different fan configurations are tested in the position of the edge fan and an empirical method is derived by which the volumetric effectiveness of an edge fan can be predicted. The experimental results are compared to CFD results for the same facility using the three different simplified simulation methods investigated previously. Particle image velocimetry (PIV) measurements are also performed upstream of the edge fan and the velocity profiles at the inlet of the fan are compared to the profiles obtained numerically. The comparisons show that the EADM predicts the performance of the edge fan more accurately than the ADM en PJM. The effect of adding a walkway and removing the bell mouth upstream of the edge fan was investigated using the EADM. The results are used to show the location of the loss mechanisms upstream of the edge fan. The addition of a walkway moves the location of the pressure loss away from the edge fan bell mouth towards the edge of the walkway. Consequently the distortion directly upstream of the edge fan is reduced and its volumetric effectiveness increased. The effect of removing the edge fan’s bell mouth is similar to the effect of adding a walkway upstream of the edge fan.<br>AFRIKAANSE OPSOMMING: Aksiaalwaaiermatrikse vorm deel van lugverkoelde kondensors in direk droëverkoelde kragstasies. Hierdie verhandeling ondersoek die werkverrigting van aksiaalwaaiers wat geleë is op die rand van ‘n groot waaiermatriks. Die randwaaiers kan ’n vermindering in deurvloei ondervind as gevolg van versteurde inlaattoestande stroom-op vanaf die waaier. Die vermindering in lugvloei lei tot ’n vermindering in die warmetoordagvermoë van die stoomkondensor en ’n gepaardgaande afname in die elektrisiteitslewering van die kragstasie. As gevolg van die fisiese grootte van die lugverkoelde kondensor is volskaalse eksperimente gewoonlik onprakties en word berekeningsvloeimeganika (BVM) gebruik om die werking van die aanleg onder verskeie toestande te modelleer. Ten einde die grootte van die BVM model te beperk, word die aksiaalwaaiers in so ‘n BVM analiese voorgestel met behulp van vereenvoudigde metodes. Drie verskillende vereenvoudigde metodes word aangebied en toegepas op ‘n BVM model van ‘n enkelwaaier, naamlik die druksprongmetode, die aksieskyfmetode en die verlengde aksieskyfmetode. Die resultate word vergelyk met eksperimentele waardes. Die vergelyking benadruk die beperkings van die modelle: Die aksieskyfmetode kan nie die werking van die waaier akkuraat voorspel by lae vloeie nie en die druksprongmetode ignoreer die variasie in lemeienskappe op verskillende liggings binne-in die waaierrotor. Die verlengde aksieskyfmetode word voorgestel as ‘n verbetering op die ander twee metodes. ‘n Veelvuldige waaiertoetsfasiliteit is saamgestel, bestaande uit drie 630 mm deursnee waaiers wat lug uit ’n gemeenskaplike inlaatkamer suig. Die inlaatkamer is so saamgestel dat een van die waaiers in die fasiliteit ‘n randwaaier verteenwoordig. Die vloerhoogte van die inlaatkamer kan aangepas word om die inlaatversteuring wat deur die raandwaaier ondervind word te vermeerder of te verminder. Ses verskillende waaierkonfigurasies is getoets in die randwaaierposisie. ‘n Empiriese metode waarmee die volumetriese effektiwiteit van ‘n randwaaier voorspel kan word is afgelei. Die eksperimentele resultate word vergelyk met ooreenstemmende BVM resultate vir dieselfde fasiliteit deur gebruik te maak van die drie verskillende vereenvoudigde metodes wat vroeër ondersoek is. Partikelbeeld snelheidsmetings word ook stroom-op vanaf die randwaaier uitgevoer en die snelheidsprofiele by die inlaat van die waaier word vergelyk met profiele wat numeries bereken word. Die vergelykings wys dat die verlengde aksieskyfmetode die werkverrigting van ’n aksiaalwaaier meer akkuraat voorspel as die aksieskyf- of druksprongmetodes. Die effek van die installering van ‘n loopvlak en die verwydering van die randwaaier se inlaatmondstuk word ondersoek met behulp van BVM deur gebruik te maak van die verlengde aksieskyfmetode. Die resultate word spesifiek gebruik om die ligging van die verliesmeganismes stroom-op vanaf die randwaaier aan te dui. Die resultate wys dat die installering van ‘n loopvlak die ligging van die drukverlies wegneem vanaf die rand van die waaierinlaat na die rand van die loopvlak. Dit verminder die inlaatversteuring stroom-op vanaf die randwaaier en die volumetriese effektiwiteit word verhoog. Die verwydering van die randwaaier se inlaatmondstuk het ‘n soortgelyke effek as die installering van ‘n loopvlak stroom-op vanaf die randwaaier.

Thesis (PhD) -- University of Stellenbosch, 2010.<br>ENGLISH ABSTRACT: In the design of a modern natural draught wet-cooling tower (NDWCT), structural and performance characteristics must be considered. Air flow distortions and resistances must be minimised to achieve optimal cooling which requires that the cooling towers must be modelled two-dimensionally and ultimately threedimensionally to be optimised. CFD models in literature are found to be limited to counterflow cooling towers packed with film fill, which is porous in one direction only and generally has a high pressure drop, as well as purely crossflow cooling towers packed with splash fill. This simplifies the analysis considerably as the effects of flow separation at the air inlet are minimised and fill performance is determined using the method of analysis originally employed to determine the fill performance characteristics from test data. Many counterflow cooling towers are, however, packed with trickle and splash fills which have anisotropic flow resistances, which means the fills are porous in all flow directions and thus air flow can be oblique through the fill, particularly near the cooling tower air inlet. This provides a challenge since available fill test facilities and subsequently fill performance characteristics are limited to purely counter- and crossflow configuration. In this thesis, a CFD model is developed to predict the performance of NDWCTs with any type of spray, fill and rain zone configuration, using the commercial code FLUENT®. This model can be used to investigate the effects of different: atmospheric temperature and humidity profiles, air inlet and outlet geometries, air inlet heights, rain zone drop size distributions, spray zone performance characteristics, variations in radial water loading and fill depth, and fill configurations or combinations on cooling tower performance, for optimisation purposes. Furthermore the effects of damage or removal of fill in annular sections and boiler flue gas discharge in the centre of the tower can be investigated. The CFD modelling of NDWCTs presents various options and challenges, which needed to be understood and evaluated systematically prior to the development of a CFD model for a complete cooling tower. The main areas that were investigated are: spray and rain zone performance modelling by means of an Euler-Lagrangian model; modelling of air flow patterns and flow losses; modelling of fill performance for oblique air flow; modelling of air pressure and temperature profiles outside and inside the cooling tower. The final CFD results for the NDWCT are validated by means of corresponding one-dimensional computational model data and it is found that the performance of typical NDWCTs can be enhanced significantly by including protruding platforms or roundings at the air inlet, reducing the mean drop size in the rain zone, radially varying the fill depth and reducing the air inlet height.<br>AFRIKAANSE OPSOMMING: By die ontwerp van ‘n moderne natuurlike trek nat koeltoring (NTNK), moet strukturele en werkverrigtings eienskappe in ag geneem word. Wanverdeelde lugvloei en vloeiweerstande moet geminimaliseer word om optimale verkoeling te bewerkstellig, wat vereis dat die koeltorings twee-dimensioneel en uiteindelik driedimensioneel gemodelleer moet word om hulle te kan optimeer. Dit is gevind dat berekeningsvloeidinamika (BVD of “CFD” in engels) modelle in die literatuur, beperk is tot teenvloei koeltorings gepak met film tipe pakking, wat net in een vloeirigting poreus is en boonop gewoonlik ook ‘n hoë drukval het, sowel as suiwer dwarsvloei koeltorings met spatpakking. Hierdie vergemaklik die analise aansienlik omdat die effekte van vloeiwegbreking by die luginlaat verklein word en die pakking se werkverrigtingsvermoë bereken kan word met die analise metode wat oorspronklik gebruik is om die pakkingseienskappe vanaf toets data te bepaal. Baie teenvloei koeltorings het egter drup- (“trickle”) of spatpakkings met anisotropiese vloeiweerstand, wat beteken dat die pakking poreus is in alle vloeirigtings en dat die lug dus skuins deur die pakking kan vloei, veral naby die koeltoring se lug inlaat. Hierdie verskaf ‘n uitdaging aangesien beskikbare pakking toetsfasiliteite, en dus ook pakking karakteristieke, beperk is tot suiwer teenvloei en dwarsvloei konfigurasie. ‘n BVD model word in hierdie tesis ontwikkel wat die werkverrigtingsvermoë van NTNK’s kan voorspel vir enige sproei, pakking en reënsone konfigurasie deur van die kommersiële sagteware FLUENT® gebruik te maak. Hierdie model kan gebruik word om die effekte van verskillende: atmosferiese temperatuur- en humiditeitsprofiele, lug inlaat en uitlaat geometrië, lug inlaat hoogtes, reënsone druppelgrootteverdelings, sproeisone werkverrigtingskarakteristieke, variasie in radiale waterbelading en pakking hoogte, en pakking konfigurasies of kombinasies op koeltoringvermoë te ondersoek vir optimerings doeleindes. Verder kan die effekte van beskadiging of verwydering van pakking in annulêre segmente, en insluiting van ‘n stoomketel skoorsteen in die middel van die toring ondersoek word. Die BVD modellering van NTNK bied verskeie moontlikhede en uitdagings, wat eers verstaan en sistematies ondersoek moes word, voordat ‘n BVD model van ‘n algehele NTNK ontwikkel kon word. Die hoof areas wat ondersoek is, is: sproeien reënsone modellering mbv ‘n Euler-Lagrange model; modellering van lugvloeipatrone en vloeiverliese; modellering van pakking verrigting vir skuins lugvloeie; modellering van lugdruk- en temperatuurprofiele buite en binne in die koeltoring. Die BVD resultate word mbv van data van ‘n ooreenstemmende eendimensionele berekeningsmodel bevestig en dit is bevind dat die werkverrigting van ‘n tipiese NTNK beduidend verbeter kan word deur: platforms wat uitstaan of rondings by die luginlaat te installeer, die duppelgrootte in die reënsone te verklein, die pakkingshoogte radiaal te verander, en die luginlaathoogte te verlaag.

The aim of this work was improve and validate the Oxylog portable oxygen consumption meter for use with draught ruminants, and to test its ability to estimate the energy expenditure of these animals in the field. Few data were available on the energy costs of the various tasks that draught ruminants perform and it was expected that the calorific factors established during laboratory experiments may not necessarily reflect the energy consumption during field work with farmers. This could have important implications in the establishment of the nutritional requirements of draught ruminants. A review of the literature on the various techniques and instruments available for the field measurement of energy consumption was carried out. A new facemask for use with the Oxylog was designed and the Oxylog equipment with this mask was validated against the open circuit gas analysis system available at the Centre for Tropical Veterinary Medicine in Edinburgh. It was found that the Oxylog on average over-estimated oxygen consumption, as measured by the gas analysis system, by 1.5%. In the second experiment, carried out with buffaloes and oxen pulling carts on the Unipalma oil-palm plantation in Meta, Colombia, the modified Oxylog system was tested in the field. Technically, the method worked satisfactorily, although the small digital displays on the Oxylog were difficult to read, and the measurements obtained generally agreed with the more established calculation methods of estimating energy consumption. It was concluded that the use of the modified Oxylog was an accurate and reliable method for the estimation of energy expenditure in the field.

This thesis considers the making and circulation of drawn and printed imagery in Britain over the period 1610-1750 with a particular emphasis on the observation and record of place. It takes as its focus the contested position of the visual image in Britain over this period, considering the place of the record of the land, past, present and future, in the making and re-making of the country. It is particularly concerned to elucidate links between different forms of depictive practice: ‘pictorial’ and ‘mathematical’, evident at the time of their making, if often lost in their interpretation in the modern literature. These depictive traditions are explored in order to examine the value of the categories of ‘real’ and ‘ideal’ that have tended to dominate narratives of landscape history. Throughout, drawings and prints are considered as forms of knowledge that combined a number of traditions and practices, aged along with those more recent. Tensions between theories and practices of image-making are central rather than incidental to the study, discovered through an examination of manuals and treatises as well as drawings and prints. There is also a recognition of the importance of collecting practices and patronage over this period, explored through the extended legacies of Lord Thomas Howard, Earl of Arundel. A focus on collections and the legacies of landscape imagery has necessitated that images be brought together from a wide range of regional and metropolitan libraries, archives and art galleries, and reconnected with the wider cultural, political and religious worlds through which they were circulated and enacted at the time of their making. Drawing on a number of disciplinary traditions, this approach offers a new perspective on topographically-informed imagery over this extended period, seeking to expand the parameters of the interpretation of such works.

The interactions of disease, work and undernutrition in draught animals were examined in three separate studies. The first study carried out in Indonesia investigated the effects of <I>Trypanosoma evansi </I>on the work output of twelve swamp buffalo in two groups. The second undertaken in the UK, used four groups of six sheep as a model to examine the effects of exercise and plane of nutrition on cellular and humoral immune responses in the absence of a pathogen. The final study in The Gambia, looked at the effects of work and undernutrition on the trypanotolerance of 32 N'Dama cattle in four groups challenged with <I>T. congolense. </I>In the first experiment work output was monitored for 11 weeks in infected and uninfected animals using a cross-over design. In the second laboratory based experiment the immune responses of sheep challenged with two foreign antigens, <I>Brucella abortus </I>and ovalbumin, were measured for 11 weeks after challenge in a factorial design with two planes of nutrition and two levels of exercise. In the third study the same factor design was adopted to examine the effects of work and undernutrition on the trypanotolerance of N'Dama cattle challenged with <I>T. congolense. </I>The results of all three studies were analysed using both parametric and non-parametric statistical tests as appropriate. In the first experiment carried out in Indonesia after a protracted period of work (5 weeks pre-infection and 4 weeks post-infection), the parasitaemias of some infected buffalo increased dramatically and this was associated with a marked decline in work output. In the second study with sheep, immune responses varied markedly between individuals but there were no significant differences between groups, with one exception, the speed of the primary antibody response to ovalbumin was significantly faster in sheep on the high plane of nutrition than in those on the low plane. In the final study work caused significant increases in animal parasitaemias and reductions in blood packed cell volumes. Some of the working cattle became so severely anaemic (PCVs < 15%) that they were unable to complete the normal daily work programme and had to be retired early, the first after only seven weeks work. In conclusion it appears that in some circumstances work can affect the course of a disease and conversely diseases can reduce work output. It is however very difficult to quantify these effects because of large differences in response between individual animals and differences in pathogenicity between different diseases and different strains of the same disease.

A literature review was conducted on several models which have been developed, based on Terzaghi's passive earth pressure theory, to describe the forces acting upon tillage implements during tillage operations. These models require a knowledge of cohesion (c) and angle of internal shearing resistance (cp) data which are not easy to obtain especially in remote areas. The main objective of the study was to establish a prediction model for the draught force required for a range of primary tillage implements under different field and soil conditions. The data obtained from the model were used to investigate whether the model was adequate for the mechanisation planning of the GAP region (South Eastern Anatolia Integrated Development Project) in Tiirkiye where by the year 2012, approximately 1.7 million ha ofland will be opened to irrigation. An effective three-point linkage dynamometer system was developed to measure the draught of implements under different soil conditions. The system consists of bi-axial Linkage Extended Octagonal Ring Transducers (LEORTs) for the lower links, a modified top link and a rotary position transducer sensing the angle of the crossshaft, together with a 21x datalogger and a portable computer. All transducers outputs were repeatable and linear with a co'efficient of determination of ~ 0.999. The output hysteresis effect was small for all transducers; the largest deviation from the mean was 1.006 % [f.s.] which occurred in the top link. Cross-sensitivity errors for the LEORTs were not significant at a maximum of 0.001 J.lV V-IN-I. A spreadsheet model was developed in order to download the data from the instrumentation system to the computer. The model is user friendly and can be used to calculate and plot the forces on the linkage system. Field experiments were conducted to determine draught force requirements of tillage implements such as a disc plough, mouldboard plough, chisel and subsoiler both under sandy loam soil conditions in UK and clay soil conditions in Tiirkiye. The standard tine which has a 450 rake angle was used as a reference tine. The field tests were Gonducted to examine the validation of a model for different soil conditions in UK such as dry, wet, light and heavy soil conditions.

In some industrial air-cooled heat exchangers, such as those in the generating set industry, the flow must turn through 90° after exiting the heat exchanger. In such arrangements, the plenum depths are typically very shallow. Furthermore., the axial fan often operates in the mixed-flow region of the fan characteristic, due to the restrictive nature of the system. These two factors lead to a reduction in the thermal performance of the system. The purpose of this study was to investigate the effect on thermal performance of inclining the heat exchanger relative to the axial fan. It was also important to compare this with simply increasing the plenum depth without inclining the heat exchanger, since inclination itself may increase the mean plenum depth. This was achieved through an isothermal experimental investigation, complemented with a numerical study using CFD. The results showed that as the heat exchanger was inclined, the low velocity core at the centre of the heat exchanger tended to move to one side. The opposite side had increased flow through the heat exchanger due to the inclination. For a mixed-flow fan operating point typical of some industries, it was found that inclination has a negligible effect on the performance of the system, when compared with a baseline case. Increasing the plenum depth also had no significant effect. At the axial fan operating point investigated, it was found that an angle of approximately 30° inclination gave the best performance. Increasing the plenum depth was found to improve the performance more than inclination. The best performing case was the non-inclined case with a plenum depth of 0.65 fan diameters. This gave an increase in flow of2.8% over the baseline case, and a corresponding 1.1 % increase in thermal performance.

Thesis (MScEng)--Stellenbosch University, 2011.<br>ENGLISH ABSTRACT: The meteorological conditions at Eskom’s Majuba Power Station are measured, evaluated and trended in this dissertation. The results are used to evaluate the current natural draught wet-cooling tower (NDWCT) design- and performance test specifications and to compare these to the original design- and performance test specifications. The evaluation reveals that the design parameters for the NDWCTs at Majuba Power Station, a cooling system that was originally designed optimally, could have been determined differently and arguably more accurately by using the wet-bulb temperature (Tawb) as the main design variable instead of the dry-bulb temperature (Ta). A new technique to determine optimal NDWCT design and performance test conditions is consequently proposed. In order to satisfy the atmospheric conditions required for a successful NDWCT performance test, it is also proposed that the tests be undertaken between 12:00 and 14:00 during Summer. It is found that the NDWCT inlet Tawb, measured at specific heights, does not compare well to the far-field Tawb measured at the same heights when a Tawb accuracy of 0.1 K is required. It is proposed that a more representative far-field Tawb measuring height of 10 m should be used in future NDWCT designs as the NDWCT design temperature reference height. The industry-standard reference height should, however, still be used during temperature profile calculations. A parametric study of the water-steam cycle and wet-cooling system at Majuba indicates that during full load conditions, the generated output (Pst) is primarily dependent on the condenser saturation pressure (pc). The latter is reliant on Tawb, the temperature lapse rate (LRT) that is represented by the temperature profile exponent (bT), the main cooling water flow rate (mcw), atmospheric pressure (pa), and wind speed (VW). Using historical plant data relatively simple methods, enabling the quick and effective determination of these relationships, are proposed. The plant-specific and atmospheric parameters required for these analyses are also tabulated. Two NDWCT effectiveness models, one mathematical (Kröger, 1998) and one statistical artificial neural network (ANN) model are presented and evaluated. ANNs, which are not often used to evaluate NDWCT effectiveness, provide accurate NDWCT temperature approach results within 0.5 K of measured values for varying dependent variables. This motivates that an ANN, if set up and used correctly, can be an effective condition-monitoring tool and can be used to improve the accuracy of more empirical NDWCT performance models. The one-dimensional mathematical effectiveness model provides accurate results under NDWCT design conditions. The dependency of Majuba’s NDWCT to the rain zone mean drop diameter (dd) is evaluated by means of the one-dimensional mathematical model. A reduction in dd from 0.0052 m to 0.0029 m can reduce the NDWCT re-cooled water temperature (Tcwo) so that the rated pc is reduced by 0.15 kPa, which relates to a combined financial saving during peak and off-peak periods of R1.576M in 2013 and R1.851M in 2016. Similar improvements can result in higher savings at other wet-cooled stations in the Eskom fleet due to less optimally-designed wet-cooling systems. The proposed techniques should be considered in future economic evaluations of wet-cooling system improvements at different power stations.<br>AFRIKAANSE OPSOMMING: Die meteorologiese toestande by Eskom se Majuba-kragstasie is deur die navorser gemeet en -evalueer. Die resultate word gebruik om die Natuurlike-trek, Nat koeltoring (NTNKT) se ontwerp- en werkverrigting toetsspesifikasies te evalueer en vergelyk met die oorspronklike toetsspesifikasies. Die resultate dui daarop dat die ontwerpsparameters vir die NTNKTs by Majuba-kragstasie, ‘n verkoelings-sisteem wat aanvanklik optimaal ontwerp is, op ‘n ander, selfs meer akkurate manier bepaal kon word deur die natbol-temperatuur (Tawb) te gebruik as die hoof-ontwerpsparameter inplaas van die droëbol temperatuur (Ta).’n Nuwe tegniek wat gebruik kan word om akkurate NTNKT ontwerp- en werkverrigting toetsspesifikasies te bepaal word voorgestel. Die tydperk vir die mees optimale atmosferiese toestande, wanneer NTNKT-toetse uitgevoer moet word, word vasgestel as tussen 12:00 en 14:00 tydens Somermaande. Dit word bewys, vir ’n Tawb akkuraatheid van 0.1 K, dat die NTNKT inlaat-Tawb, gemeet by verskillende hoogtes, nie vergelykbaar is met Tawb wat ver van die NTNKT af op dieselfde hoogtes gemeet word nie. ’n Meer aanvaarbare hoogte van 10 m word voorgestel as die NTNKT ontwerpstemperatuur verwysingshoogte vir toekomstige NTNKT ontwerpe wanneer die Tawb ver van die NTNKT af meet word. Die industrie-standaard temperatuur verwysingshoogte moet wel steeds gebruik word tydens temperatuur-profielberekeninge. ’n Parametriese studie van die turbine se water-stoom siklus en die nat-verkoelingstelsel by Majuba dui daarop dat die generator se uitset (Pst) hoofsaaklik afhanklik is van die kondensator se druk (pc) gedurende vol-vrag toestande. Druk (pc) is weer afhanklik van Tawb, die temperatuur vervaltempo (LRT) wat voorgestel word deur die temperatuur profiel eksponent (bT), die verkoelingswater-vloeitempo (mcw), atmosferiese druk (pa) en windspoed (VW). Deur die gebruik van historiese data word redelike eenvoudige metodes voorgestel om dié verhoudings doeltreffend te bepaal. Die atmosferiese- en stasie-spesifieke parameters wat benodig word vir dié ontleding is ook getabuleer. Twee modelle vir NTNKT-effektiweit, ’n wiskundige (gebaseer op Kröger, 1998) en statistiese kunsmatige neurale-netwerk (KNN) model, word aangebied en geëvalueer. KNNe, wat nie gereeld gebruik word om NTNKTe se effektiwiteit te evalueer nie, lewer akkurate NTNKT temperatuur-benadering resultate binne 0.5 K van die gemete resultate vir wisselende afhanklike parameters. Dié resultate motiveer dat ’n KNN wat korrek opgestel is doeltreffend gebruik kan word om die toestand van NTNKTs te bepaal en om die akkuraatheid van ander NTNKT-modelle te verbeter. Die eendimensionele, wiskundige model lewer akkurate resultate onder NTNKT ontwerpspesifikasies. ’n Wiskundige NTNKT-model word gebruik om die afhanklikheid van Majubakragstasie se NTNKTe tot die reënsone druppelgrootte (dd) te bereken. 'n Vermindering in dd van 0,0052 tot 0,0029 m kan die NTNKT se afgekoelde watertemperatuur (Tcwo), van só 'n aard verlaag dat pc verminder met 0,15 kPa. Só kan ’n gesamentlike vol- en gedeeltelike vrag finansiële besparing van R1.576M in 2013 en R1.851M in 2016 behaal word. Soortgelyke verbeterings aan verkoelingstelsels sal lei tot meer en hoër besparings by ander Eskom nat-verkoelde stasies. Dié tegnieke moet in ag geneem word tydens toekomstige ekonomiese evaluasies van verbeterings tot nat-verkoelingstelsels by ander kragstasies.

Nuo to, kaip elgiasi individas priklauso, kokia bus jo sveikata. Sveikatai žalingas elgesys turi daug formų: alkoholio, tabako, kitų narkotinių medžiagų vartojimas, neatsakingas ar per ankstyvas lytinis aktyvumas. Tyrėjai yra pastebėję, jog lytinės brandos pradžia ir alkoholio vartojimas padidėjęs depresiškumas, ankstyvas seksualinis gyvenimas turi glaudžių sąsajų. Darbo tikslas – ištirti ankstyvosios lytinės brandos ir draugų elgesio sąsajas su sveikatai žalingu elgesiu paauglystėje. Palyginti ankstyvosios lytinės brandos paauglių, turinčių draugų, kuriems būdingas sveikatai žalingas elgesys, elgesį, su tokių draugų turinčių, kito lytinės brandos statuso paauglių elgesiu. Tyrime naudotas Jessor R. modifikuotas probleminio elgesio klausimynas, bei lytinio brendimo skalė. Tyrime dalyvavo 198 (84 berniukai ir 114 mergaitės) 14 – 19 metų tiriamieji amžius. Iš jų 50 buvo priskirti ankstyvosios lytinės bandos grupei. Tyrimo rezultatai atskleidė, jog sveikatai žalingas elgesys yra labiau būdingas berniukams negu mergaitėms, taip pat, kad ankstyvoji lytinė branda turi mažai sąsajų su sveikatai žalingo elgesio pasireiškimu ir tai, jog yra daugiau sąsajų tarp draugų elgesio ir sveikatai žalingo elgesio pasireiškimo, negu tarp sveikatai žalingo elgesio pasireiškimo ir ankstyvosios lytinės brandos.<br>Pubertal processes have a major effect on physical, psychological, and social development. Early pubertal timing is associated with early initiation of alcohol, sexual behaviour, drug use and deviance in adolescence. The aim of this study was to examine the relationship between pubertal statuses, peer behaviour and health behaviour in adolescence. Children reported their pubertal development status and timing using a self-report Pubertal Development Scale and Jessor R. questionnaire of Problem Behaviour. There were 198 (84 boys and 98 girls) investigate in the study. The findings demonstrated that boys were more likely than girls to use alcohol, drugs and have early sexual intercourse. There were no associations between puberty, peer behaviour and health behaviour, but there are association between peer behaviour and health behaviour.

Goal of the paper: examine and evaluate stress and stressors of the senior pupils (that attend the 11th-12th forms). Objectives: Identify stressors of the urban and regional pupils and evaluate possible territorial differences. Learn about pupils’ subjective evaluation of their health state. Set recommendations for the prophylaxis of pupils’ stress. Research material and methods: 521 senior pupils - 286 from Kaunas and 235 from Birzai - were selected at random and questioned. The stress-evaluating questionnaire covered two parts: scale of subjectively perceived stress (10 points) and stress-evaluating scale for the juvenile. The pupils were also questioned about the issues of smoking, use of strong drinks. They were asked to mark all the symptoms that bothered them through the past 12 months. The statistical data analysis was performed by means of a statistical package “SSPS 11.5”. Results: 29.9% out of 521 pupils that were questioned experience slight stress, 46.3 % - great stress, and 23.8%- enormous stress. The major stressors of the aforementioned pupils are lack of sleep (70.6%), arguments with family and friends (62.2%), problems at school (39.0%), use of alcohol and drugs (36.5%). Girls usually pinpoint arguments with family and friends, separation, alteration of living conditions. Boys distinguish more often the use of strong drinks and drugs or a misdemeanor. It has been noticed that the more pupils use strong drinks (starting with abstinence and continuing with... [to full text]

In this work are analyzed the problems of how music demands are revealed in pedagogical and psychological literature as well as the problem of genesis, motivation, the influence of valuable orientation to music demands and their adjustment. The problem of how music demands are classified, what musical needs are among students in different age groups and what influence education can have to satisfy students‘ needs are trying to be solved out in this work. The research carried out in Juozas Balčikonis gymnasium and Vytautas Žemkalnis gymnasium among 9-12th formers helped to purify family influence to meet students music needs. It allowed to form a set of recommendations on how students can increase the satifaction of their music needs in families. The research also showed the necessity to satisfy their needs while communicating with friends. It is found out that learning music at school has a positive influence to students‘ music needs. The fact of a small number of students playing music was established. The most interesting musical activity among students is found out, which should encourage teachers to pay more attention to it. A part of students‘ free time devoted to attending concerts is defined. According to the research, professional perfomances should be organized in gymnasiums. The tendency that students spend most of their free time in entertainment centers was exposed. It should induce teachers to increase the culture of entertainment and change students‘ attitude... [to full text]

Tyrimo objektas – Mokinių socialinės paramos, fizinės aplinkos ir mokymosi pasiekimų sąsajos su fiziniu aktyvumu Tyrimo tikslas – Nustatyti 8–9 klasių mokinių socialinės paramos, fizinės aplinkos ir mokymosi pasiekimų sąsajas su fiziniu aktyvumu. Uždaviniai: 1. Nustatyti mokinių fizinį aktyvumą lyties ir amžiaus aspektu. 2. Nustatyti socialinė paramos įtaką mokinių fiziniam aktyvumui. 3. Nustatyti fizinės aplinkos įtaką mokinių fiziniam aktyvumui. 4. Nustatyti mokinių mokymosi pasiekimus skirtingo fizinio aktyvumo aspektu. 5. Nustatyti fizinio aktyvumo, socialinės paramos įtakos, fizinės aplinkos ir mokinių mokymosi pasiekimų tarpusavio sąsajas. Išvados: 1. Tyrimo metu nustatyta, kad 52,2 proc. tirtų mokinių buvo fiziškai aktyvūs ir 47,7 proc. pasyvių, fiziškai aktyvesni buvo vaikinai (p<0,05), fiziniu aktyvumu dažniau užsiima vyresni mokiniai. Dauguma mokinių fiziniam aktyvumui per savaitę skiria po 2–3 kartus per savaitę. Fiziškai aktyvesni mokiniai subjektyvų savo fizinį aktyvumą ir pajėgumą vertino aukštesniais balais. 2. Nustatyta, kad tėvai palaiko ir paremia jaunesnius mokinius ir vaikinus fiziniam aktyvumui (p<0,05). Tyrimo metu nustatyta, kad tėvai mažiau domisi vyresnio vaiko fiziniu aktyvumu, nei jaunesnio, o taip pat vaikinus fiziniam aktyvumui remia mažiau, nei merginas. Išanalizavus draugų įtaką mokinių fiziniam aktyvumui pastebėjome, kad vyresnių klasių mokiniai kur kas dažniau siūlo užsiimti fiziniu aktyvumu kartu. Šiuo atveju jaunesni mokiniai savo... [toliau žr. visą tekstą]<br>The object of research – Students of social support, physical environment and learning outcomes interfaces with physical activity The aim – Set of 8-9 grade students of social support, physical environment and learning outcomes relationship with physical activity. Objectives: 1. Set the physical activity of students by gender and age. Third set of physical environment on students physical activity. 2. Identify social support impact on student physical activity. 3. Identify the physical environment on students' physical activity. 4. Identify students' learning achievements of different aspects of physical activity. 5. Set physical activity, social support influence the physical environment and the students' learning achievement between the interfaces. Conclusions: 1. The study found that 52,2 rate surveyed students were physically active and 47,7 rate passive, were more physically active males (p<0,05), physical activity, older students more engaged. Most of the students' physical activity per week to 2 – 3 times a week. Physically active students of their subjective physical activity and capacity by higher scores. 2. It was found that parents support and support younger pupils and boys physical activity (p<0,05). The study found that parents are less interested in the older child's physical activity than younger, but also guys supporting physical activity less than girls. The analysis of students' friends and influence physical activity found that older students much more... [to full text]

Thesis (Ph.D.)--University of Stellenbosch, 2000.<br>ENGLISH ABSTRACT: The primary purpose of this dissertation is to further the understanding of the influence of plenum chamber aerodynamic behaviour on mechanical draught air-cooled heat exchanger (ACHE) performance. The investigation, which included both forced and induced draught ACHEs, was conducted through the use of a commercially available computational fluid dynamics (CFD) code. A numerical axial flow fan and heat exchanger model that simulates the effect of the axial flow fan and heat exchanger bundle respectively on the flow field within the ACHE was developed and included in the CFD-code through user-programming. Where appropriate the numerical investigation was augmented with experimental data. The plenum chamber aerodynamic behaviour is characterised and included in the draught equations associated with forced and induced draught ACHEs through the introduction of dimensionless plenum chamber recovery and plenum chamber loss coefficient respectively. The influence of changes made to a range of mechanical draught ACHEs on plenum chamber aerodynamic behaviour was investigated. These changes include: • Operating conditions of the axial flow fan. • The height of the plenum chamber in the fan axial direction. • The heat exchanger bundle isothermal flow resistance. • The fan to heat exchanger area ratio. • The axial position of the fan in the fan casing. From the results of the numerical investigation a set of design guidelines are set for both forced and induced draught ACHEs. The design guidelines include recommended values for the dimensionless plenum chamber recovery and plenum chamber loss coefficient to be used in the respective draught equations enabling a more accurate prediction of the operating point of a proposed mechanical draught ACHE. KEYWORDS: air-cooled heat exchanger numerical investigation plenum chamber aerodynamic behaviour<br>AFRIKAANSE OPSOMMING: Die primere doel van hierdie proefskrif is om die kennis aangaande die invloed van plenum ruimte lugdinamiese gedrag op die werking van meganiese-trek lugverkoelde warmteruilers (LVWRs) te verbreed. Die ondersoek wat geforseerde- asook geinduseerdetrek LVWRs ingesluit het is uitgevoer deur gebruik te maak van In kornmersiele verkrygbare berekeningsvloeimeganika-pakket. In Numeriese aksiaalwaaier- en warmteruilermodel wat die invloed van respektiewelik die aksiaalwaaier en die warmteruiler op die vloeiveld in die LVWR simuleer is ontwikkel en in die berekeningsvloeimeganika-pakket geinkorporeer d.m.v gebruikers-roetines. Waar van toepassing is die numeriese ondersoek aangevul met eksperimentele data. Die plenumruimte lugdinamiese gedrag word gekarakteriseer en ingesluit in die onderskeie trekvergelykings vir geforseerde- en geiduseerde-trek LVWRs deur die daarstelling van In dimensielose plenumruimteherwinnings- en plenumruimteverlieskoeffisient. Die invloed van veranderinge wat aangebring is aan In reeks meganiesetrek LVWRs op die plenumruimte lugdinamiese gedrag is ondersoek. Hierdie veranderinge sluit die volgende in: • Die werking van die aksiaalwaaier. • Die hoogte van die plenumruimte in die aksiale rigting van die waaier. • Die isotermiese lugweerstand van die warmteruiler. • Die waaier-tot-warmteruiler area-verhouding. • Die aksiale posisie van die aksiaalwaaier in die waaierring. In Stel ontwerpsriglyne Vir beide geforseerde- en geinduseerde-trek LVWRs word geformuleer gebaseer op die resultate van die numeriese ondersoek. Die ontwerpsriglyne sluit aanbevole waardes vir die dimensielose plenumruimte-herwinnings- en plenumruimteverlieskoeffisient in wat op hulle beurt aangewend kan word om In meer akkurate aanduiding van die werkspunt van In beplande LVWR te bereken deur gebruik te maak van die toepaslike trekvergelyking. SLEUTEL WQORDE: lugverkoelde warmteruiler numeriese ondersoek plenurnruimte, lugdinamiese gedrag

In South Africa, nearly 80 % of electricity is generated from coal fired power plants. Due to the complexity of the interconnected systems that make up a typical power plant, analysis of the root causes of load losses is not a straightforward process. This often leads to losses incorrectly being ascribed to the Induced Draught (ID) fan, where detection occurs, while the problem actually originates elsewhere in the plant. The focus of this study was to develop and demonstrate a modelling methodology to quantify the effects of major plant anomalies on the capacity of ID fans in coal fired power plants. The ensuing model calculates the operating point of the ID fan that is a result of anomalies experienced elsewhere in the plant. This model can be applied in conjunction with performance test data as part of a root cause analysis procedure. The model has three main sections that are integrated to determine the ID fan operating point. The first section is a water/steam cycle model that was pre-configured in VirtualPlantTM. The steam plant model was verified via energy balance calculations and validated against original heat balance diagrams. The second is a draught group model developed using FlownexSETM. This onedimensional network is a simplification of the flue gas side of the five main draught group components, from the furnace inlet to the chimney exit, characterising only the aggregate heat transfer and pressure loss in the system. The designated ID fan model is based on the original fan performance curves. The third section is a Boiler Mass and Energy Balance (BMEB) specifically created for this purpose to: (1) translate the VirtualPlant results for the steam cycle into applicable boundary conditions for the Flownex draught group model; and (2) to calculate the fluid properties applicable to the draught group based on the coal characteristics and combustion process. The integrated modelling methodology was applied to a 600 MW class coal fired power plant to investigate the impact of six major anomalies that are typically encountered. These are: changes in coal quality; increased boiler flue gas exit temperatures; air ingress into the boiler; air heater inleakage to the flue gas stream; feed water heaters out-of-service; and condenser backpressure degradation. It was inter alia found that a low calorific value (CV) coal of 14 MJ/kg compared to a typical 17 MJ/kg reduced the fan's capacity by 2.1 %. Also, having both HP FWH out of service decreased the fan's capacity by 16.2 %.

Donkeys are becoming increasingly important for draught animal power (DAP) in Zimbabwe and the sub-Saharan region mainly because cattle, the traditional DAP source, have suffered high mortalities in recent droughts. However, there is limited information on the extent of use and potential of donkeys for DAP in Zimbabwe. To rectify the deficiency, two surveys and a series of studies were undertaken. In the first survey, a rapid rural appraisal (RRA) was undertaken to assess the status, role and management practices of DAP in smallholder farming areas in the semi-arid regions of Zimbabwe. The second survey assessed the morphological attributes of 335 working donkeys, the relationships between live weight and body measurements and the effect of seasonal fluctuations of herbage availability on live weight and body condition of the donkeys. This was followed by experiments to measure the draught performance at ploughing and to investigate the effects of water and work on dry matter intake (DMI) by donkeys. The results of the RRA showed that large numbers of cattle died during the 1991-92 drought (up to 75 per cent in some areas) and that this had increased the farmers' dependency on donkeys for DAP. The management of donkeys was generally inadequate. For example, there was widespread use of the inappropriate neck yokes on donkeys in some of the areas. The survey on morphological attributes indicated that the typical "Zimbabwean" donkey weighed 142 kg, had a heart girth of 115 cm, a withers height of 105 cm and was normally light grey in colour. Male and female donkeys were similar in size. The single best predictor of live weight was heart girth (r<SUP>2</SUP> = 0.864) followed by umbilical girth (r<SUP>2</SUP> = 0.753). Donkeys lost weight and body condition during the late dry season. When used for ploughing in the wet season, donkey and cattle teams of similar total team weights exerted a similar draught force (863 N (±49.6) and 912 N (±98.2), P>0.05), generated similar power output (743 W (±68.8) and 938 W (± 140), P>0.05), worked at similar speeds (862 m/s (±69.5) and 1012 m/s (±64.3), P>0.05) and had similar effective field capacities (14.9 hours/ha (± 1.30) and 13.6 hours/ha (± 1.46), P>0.05), respectively.

The objectives of this thesis were to i) determine the energy expenditure of draught oxen performing common farm operations, ii) establish the relationships between work on intake and digestibility of feeds by draught oxen, iii) investigate the effect of body condition before work and live weight losses during work on work output, and iv) investigate the implications of heat stress on draught oxen in semi-arid areas. The ultimate aim of this study was to generate information necessary for the design of feeding and working strategies for draught animals in semi-arid areas. To meet these objectives four experiments were conducted at the ICRISAT Sahelian centre, with the collaboration of the International Livestock Centre for Africa. In the first experiment the Oxylog, a portable breath by breath gas analyser, was used on 7 animals to determine their standing metabolic rate, their energy cost of walking on soils of different consistencies, and their efficiency of doing work, i.e. ploughing and carting. The average standing metabolic rate of animals was 487 (± 10.6) kJ/kg LW<SUP>0.75</SUP>. The consistency of the soil on which animals were working had a marked effect on their energy cost of walking which was 1.59 (±0.069), 2.15 (±0.084) and 1.0 (±0.10) J/m/kg live weight on unploughed land, ploughed land and laterite tracks, respectively. The efficiency of ploughing sandy soils was 0.32 and was not significantly different from the efficiency of carting with different loads. The efficiency of doing work was not influenced by the type of work performed, the draught force exerted or the walking speed. In the second experiment intake of millet stover, water intake, live weight, plasma concentrations of T3, T4 and urea-nitrogen were measured on 18 animals that worked for 0, 2 or 4 h/day in sequence during three 3-week experimental periods. In addition to these variables, the digestibility and rate of passage of feeds through the digestive tract were measured during the third experiment on 12 animals working either 0, 2.5 or 5 h/day in sequence during three 2-week experimental periods. In the fourth experiment feed intake was measured on 18 animals of different body condition that worked 4 days a week for 7 weeks. The absence of effect of work on intake of millet stover was consistent during these experiments. The efficiency of utilisation of eaten roughages and the rate of passage of the digesta in the gastro-intestinal tract were not influenced by work either. This suggests that the nutrient supply from intake of roughages by working oxen and bulls is unlikely to be sufficient to compensate for the extra energy expended during work. Feed intake was however significantly affected by the quality of the millet stover fed and by the body condition of the animal.

Energy use in buildings account for about one third of the total global energy supply and contributes as much as 30% of the anthropogenic greenhouse gas emissions. It is estimated that energy use in buildings will increase to 67% by 2030. The need for better thermal comfort and air quality in indoor environments is the leading cause for high energy use in buildings.  Heating, ventilation and air conditioning systems take up about 50% of the total energy use in buildings which is about 10-20% of the national energy use in most developed countries. The development and adoption of sustainable ventilation systems is a viable solution to mitigate climate change and curtail carbon emissions. The experimental study was conducted in a room resembling a modern office in a laboratory environment. The study involved investigating the ability of the system to provide cooling and heating. Concentration decay tracer gas technique using Sulphur hexafluoride (SF6) gas was used to determine the local air change index and air change efficiency in the room. Low-velocity omni-directional thermistor anemometer type CTA88 were used to measure the air velocity and temperature in the room. Smoke was used to visualise the flow patterns created in the room.  The climate chamber was used to mimic climatic conditions in winter. Fifteen cases were investigated with five air flow rates set points (30, 40, 50, 60 and 70 l/s) at three supply air temperatures, i.e., 17.6 °C, 21.0 °C and 25.3 °C. The results of the local air change index and air change efficiency for the nominal supply temperature of 17.6 °C showed that the system had strong characteristics of a mixing ventilation system. At the supply air temperature of 21.0 °C, the performance of the system deteriorated slightly to below that of a mixing ventilation system and could not satisfactorily provide heating at supply temperature of 25.3 °C. Better performance of the system at all supply air temperature setpoints was observed at lower airflow rates. At all supply air temperature setpoints, relatively higher degree of temperature stratification was observed at lower supply. The draught rate levels decreased with increase in supply air temperature and height. The location of the air inlet terminals in relation to the workstations had significant effect on the performance of the system. The stratum ventilation system did not work efficiently because the air streams were heavily mixed before reaching the occupants.

Falu Gruvas hästar har historiskt sett varit av stor betydelse för det dagliga arbetet vid gruvan. De användes ovan jord för transport av bland annat ved och malm, men även för att driva de många hästvindar som från och med 1540-talet användes för uppfordring samt för att pumpa upp grundvatten ur gruvan. Mellan 1697 och 1815 arbetade även hästar under jord med att driva hästvindar samt frakta malm. Dessa hästar hissades till en början ned i gruvan genom schakten dagligen, men fick sedan bo nere i gruvan där de kom att tillbringa merparten av sina liv. Uppsatsen ger en bred bild av flertalet aspekter av hästarnas liv, med fokus på tiden 1540 till 1815 då hästarna var som viktigast för att hålla igång gruvdriften. Trots hästarnas framstående roll i gruvans historia har de aldrig haft någon framträdande roll i historieskrivningen. Denna uppsats syftar till att skildra Falu Gruvas historia med hästen i fokus.<br>Falu mine horses have historically been of great importance for the daily work at the mine. They were used above ground for the transportation of for example wood and ore, but also to power the many horse capstans that were used for hoisting and for pumping groundwater out of the mine. Between 1697 and 1815 horses began to work underground as well, with running horse capstans and with transportation. At first, these horses were lowered to the bottom of the mine every day, but later they came to live below ground. This study gives a broad picture of several aspects of the horse's life, focusing on the period from 1540 to 1815, when the horses were very important to the mine. Despite the horses' prominent role in the mine's history, they have never fully been portrayed in historiography. This study aims to do that.

O Rio Grande do Sul possui um grande potencial para a navegação interior devido à extensão de sua rede hidrográfica de quase 2200 km, sendo 930 km navegáveis. Aliado a isto, na última década o estado apresentou um crescimento econômico em relação ao Produto Interno Bruto (PIB) de 167,2 %, segundo a Fundação de Economia e Estatística/RS. Mesmo com estas condicionantes favoráveis constata-se que o modelo atual da estrutura logística da movimentação de cargas continua a não privilegiar o setor hidroviário interior. Tendo em vista estes aspectos, esta dissertação apresenta um estudo cujos objetivos são: (i) identificar a representatividade do modal hidroviário interior em relação à movimentação de cargas, destinadas à exportação e importação, da metade norte do Rio Grande do Sul aos principais terminais privados hidroviários e ao porto público, localizados na cidade de Rio Grande; (ii) comparar o modal hidroviário com seus principais concorrentes, os modais rodoviário e ferroviário e (iii) avaliar o impacto econômico da adoção do calado sazonal. Para a comparação dos modais foram escolhidos três parâmetros que estabelecem custos em relação à tonelada quilometro transportada, são eles: custo médio de operação; custo despendido com combustíveis; e custos sociais. Após as informações coletadas foram processadas e analisadas, possibilitando identificar os custos gerados por cada modal. Na comparação destaca-se que o custo dos modais rodoviário e ferroviário são respectivamente 1541% e 405% maior do que o hidroviário interior e que a carga movimentada pelos três modais, em 2011, representou um custo total de R$ 1,79 bilhões, ou seja, 0,65% do PIB estadual. Na avaliação da adoção do calado sazonal foi estudado o possível ganho em termos de capacidade de transporte de cargas e a redução de custos gerada pela utilização do transporte hidroviário interior, no Rio Grande do Sul, decorrentes da possível implantação da permissividade de um calado sazonal, em função da variação histórica dos níveis de água, verificados através das curvas de permanências em nove estações pluviométricas localizadas na Laguna dos Patos e no Lago Guaíba. Constatou-se que a adoção do calado sazonal, no ano de 2011, teria um impacto de redução de custos de transporte na ordem de R$ 40,7 milhões, considerando a migração do modal rodoviário para o hidroviário e de R$ 10,1 milhões se fosse considerado a migração do modal ferroviário para o hidroviário.<br>The state of Rio Grande do Sul (RS), in Brazil, has a significant potential for internal navigation due to the extent of its drainage network of almost 2,200 km, of which 930 km are navigable. Allied to this, in the last decade the state had an economic growth in relation to Gross Domestic Product (GDP) of 167.2%, according to the Foundation of Economics and Statistics/RS. Even with these favorable conditions it appears that the current model of logistic structure of shipment continues to not emphasis on the internal waterway sector. Considering these aspects, this dissertation presents a study whose objectives are: (i) identify the representativeness of the interior waterways in relation to handling, for export and import, the northern half of Rio Grande do Sul to the main private terminals waterway and the public port, located in the city of Rio Grande , (ii) compare the waterways with its main competitors, the road and rail modes, and (iii) evaluate the economic impact of the adoption of the draft season. To compare the modals, three parameters that establish costs in relation to the tone kilometers transported were chosen, they are: average cost of operation, cost spent on fuel, and social costs. After the data were processed and analyzed, it was possible to identify the costs generated by each mode. In comparison it is emphasized that the cost of road and rail modes are respectively 405% and 1541% higher than the inland waterway and the shipment handled by the three modes, in 2011, represented a total cost of R$1.79 billion, i.e. 0.65% of the state GDP. In assessing the adoption of the draft seasonal possible gain was studied in terms of load carrying capacity and reducing costs generated by the use of inland waterway transport, in Rio Grande do Sul, from the possible deployment of the permittivity of a quiet season in function of the historical variation in water levels, checked through the curves stays in nine rainfall stations located in the Patos Lagoon and Lake Guaiba. It was found that the adoption of the draft season , in 2011, would have an impact of reducing transport costs in the order of R$40.7 million, considering the migration from road transport to waterways and R$10.1 million if found migrating the railroad to the waterway.

The topic of this diploma thesis is heating of apartment buildings, where an attention was focused on thermal comfort in heated rooms. The first theoretical part brings results of CFD simulations which compare radiators with floor heating. The second part consits of practical application o the given building. There are two options in this project - heating by radiators or floor heating. The third part describes two experiments - measurement of indoor environment in two rooms and measurement of gas consumption in apartment buildings with different heating concepts. In the last part the mean radiant temperature is simulated. There are compared different kind of heating, which have impact to distribution of mean radiant temperature in the room. The personal software was created for deeper understanding of mean radiant temperature.

James Joyce's interest in theater and cinema have led many to assume that both have heavily influenced his work. While such an assumption is somewhat valid, it ignores those characteristics of Joyce's fiction that are distinctly theatrical rather than cinematic--his reliance on dialogue over description, and thus the word over the image, and his panoramic rather than closeup vision--as well as the major differences between the theater and the cinema. Furthermore, by asserting that cinema influenced Joyce, critics ignore the fact that when cinema was beginning to implement the techniques they find in Joyce's work, Joyce had already written Dubliners, A Portrait of the Artist as a Young Man, and most of Ulysses This study explores the cinematographic versus theatrical characteristics of Joyce's novels by examining his techniques in light of the distinguishing characeristics of the two genres. I use dramatic adaptations of his prose works to demonstrate that these techniques are indeed ones that operate in the genres themselves, recognizing that while adaptations are somewhat influenced by the skill of the adaptor, the portions of an adaptation which work well or badly do so partly because of the original. This is especially true of the adaptations I have chosen because most of them lift whole sections of the novels virtually unchanged, making the adaptations even more useful as gauges of the theatrical or cinematic characteristics of their originals I consider three adaptations of Joyce's A Portrait of the Artist as a Young Man: Joseph Strick's film (same title), Hugh Leonard's Stephen D, and Phoebe Brand, John Randolph, and Frederick Ewen's A Portrait of the Artist as a Young Man. (All three also draw some of their material from Stephen Hero.) For Ulysses, I consider six adaptations: Joseph Strick's film Ulysses, Eamon Morrissey's Joycemen, Joseph Carroll's Mr. Bloom and the Cyclops, Donna Wilshire's Molly Bloom's Soliloquy, Marjorie Barkentin's Ulysses in Nighttown, and Louis Zukofsky's unpublished filmscript. For Finnegans Wake, I consider five adaptations: Mary Ellen Bute's film adaptation by the same title, Davie Heefner's play by the same title, Mary Manning's The Voice of Shem, Jean Erdman's Coach with the Six Insides, and Stuart Gilbert's unproduced scenario for Anna Livia Plurabelle<br>acase@tulane.edu

碩士<br>國立臺北科技大學<br>冷凍與低溫科技研究所<br>90<br>Draft can be defined as an unwanted feeling owing to locally convective cooling of human body caused by air movement. Usually, it is one of the main reasons to make people feel uncomfortable in an air-conditioning environment. Therefore, the discomfort caused by draft has close relation with people’s sensation on the indoor airflow characteristics. According to the studies of American and European countries, it is known that the main factors to cause draft include mean velocity, mean temperature, turbulence intensity, direction and fluctuating frequency of airflow. When the airflow frequency of fluctuation falls between 0.2 and 0.6Hz, the extent of discomfort caused by draft reaches the maximum. In this study, experimental results regarding to the distribution of airflow frequency of fluctuation generated by the split-type air-conditioner is discussed. Also, the relation of fluctuating frequency of airflow and draft is outlined. According to the experimental investigation, most frequency of fluctuation falls in the range of discomfort. In addition, both theoretical and CFD methods are used to investigate the sensation of people’s skin temperature on the changes of environmental temperatures. The relation of the change of skin temperature and thermal comfort is also discussed.

碩士<br>國立臺北科技大學<br>能源與冷凍空調工程系碩士班<br>100<br>This study is about the air distribution simulation of chilled beam systems. The temperature and velocity field were analyzed so to determine the draught rate (DR%) for the application of chilled beam air-conditioning. The common problems of the chilled beam system such as coil condensation were addressed as Taiwan is located in high temperature and humidity region. Therefore the chilled beam design requires appropriate consideration of outdoor air volume and humidity control so to prevent coil condensation. Pre-cooling before work hours is can be solution for the above problems. An actual case was analyzed with eQuest for cooling, then an accurate assessment of supply water temperature and flow rate can be calculated so to avoid the condensation. Different induction ratio (5, 4 and 3) and chilled beam spacing (3.6m, 3.8m, 4.0m and 4.2m) were investigated for the impact on the air distribution. The results show that different induction ratio has no obvious influence on the temperature distribution, and could be due to small difference in total air volume. The common point for all the cases is that the air velocity is higher and the temperature is lower at 0.1m height level than at 1.1m height level. The mean air velocity is at 0.1m is higher than 1.1m for about 30 ~ 60%. In addition for chilled beam spacing above 4.0m the airflow and temperature distribution is more even. Then higher comfort would be achieved. In ISO 7730 standard a thermal comfort indicator DR% is the discomfort level expressed as the percentage of people predicted to be unsatisfied. This value can be used in the design and construction of air-conditioning systems. For the air supply of chilled beam counter direction is better than parallel flow as it would result in lower DR%. The DR% is proportional to the mean air velocity that affects persons in a room. For the seven cases studied DR% at 0.1m level is higher than 1.1m level for about 47 ~ 93%. It can also be seen that the temperature and velocity fields are affected by the heat source. In summary for the cases studied the mean air velocity and DR% are mostly higher than the recommended value of the ISO7730 standard. The probable cause could be the cooling load is about 80m2 /W, greater than the nominal value of 70m2 /W.

M. Tech. Agriculture<br>Shortly after World War two (WWII), the South African government responded to the mounting food production crisis in the homelands by introducing public tractor services. Establishment of irrigation schemes and provision of public tractor services for use by smallholders were two important government-initiated modernisation projects in the homelands. It was in line with the idea of modernisation that smallholder irrigation schemes were the prime target for public tractor services, and this lead to the rapid abandonment of the use of animal draught for cultivation on these schemes. By the time public tractor services were completely dismantled, cultivation on smallholder irrigation schemes had become almost entirely dependent on tractor draught. Thereafter, hiring the services of privately owned tractor enterprises became the principal way in which farmers on smallholder irrigation schemes in Limpopo Province cultivated their plots. The rising cost of hiring private tractors placed financial stress on the cropping enterprises of smallholder irrigators, generating interest in alternatives that were more affordable. Animal draught represents an attractive alternative to tractor draught. Whereas prevailing economic circumstances on smallholder irrigation schemes favour the adoption of cultivation systems that are cheaper than those offered by private tractor enterprises, it is not known whether animal draught land preparation enterprises are an appropriate alternative to the existing tractor enterprises from an economic and social perspective. In order to resolve this knowledge problem, the current study was done with the following two main objectives: to determine the profitability of the different types of land preparation enterprises operating on smallholder canal irrigation schemes in Vhembe District Municipality; and to determine the social acceptability of these different types of land preparation enterprises by measuring the perceptions of the quality of the cultivation services provided by these enterprises among plot holders on these schemes.

John 21 tells of the “miraculous draught of fishes.” The disciples fish all night and catch nothing. In the morning, they fail to recognize Jesus on the shore, instructing them to cast their net again. After an amazing catch and subsequent breakfast, Jesus thrice questions Peter’s love and commissions him to “feed my sheep.” Using Narrative Criticism, this study examines this recognition scene, specifically in light of recognition scenes in Genesis. Previous work used primarily Greco-Roman texts to analyze Johannine recognition. This study adds the Hebraic perspective, asking, “How would a reader, well acquainted with Genesis, understand recognition in John 21?” This study labels characters who withhold recognition from others as “manipulators,” and argues that biblical recognition can be understood within a context of “manipulation.” It proposes a taxonomy of manipulation with six narrative kernels. This yields four patterns gleaned from Genesis: 1) Manipulation narratives are focused around chosen leaders—manipulators—undergoing a character development process; 2) These manipulators disempower others while empowering themselves for gain; 3) Genesis manipulation stories often contain evocative déjà vu motifs: repetitive words and themes connecting the units, reinforcing the story, and sometimes haunting manipulators; 4) Manipulators are often “counter-manipulated” in a reciprocal manner ironically similar to their own previous behavior. This may correct and transform the manipulator. The taxonomy and patterns are applied to John 21:1-19 as a lens for a new reading. The study also examines Greek diminutives in John 21, which enhances the reading. This reading characterizes Peter’s earlier behavior in John 18 as manipulative, when he withheld his identity three times. When the disciples go aimlessly fishing in John 21, Jesus actively withholds his identity in ironic counter-manipulation, mirroring Peter’s earlier denials. The disciples’ lack of recognition underscores their dullness, especially Peter’s. Jesus’ three questions to Peter continue the ironic counter-manipulation, paralleling Peter’s earlier three denials. Finally, Jesus predicts Peter will glorify God in his death, indicating his future turn toward ideal discipleship.<br>New Testament<br>D. Th. (New Testament)