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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

An ecological integrity assessment of the lower Amatikulu, Thukela and Umvoti rivers, KwaZulu-Natal, South Africa / Johannes Jacobus Venter

Venter, Johannes Jacobus January 2013 (has links)
The ecosystem services of the lower Amatikulu, Thukela and Umvoti Rivers are used extensively through sugarcane agricultural activities, heavy industries and rural sewage-treatment works. These activities affect the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers. The Umvoti River is already being referred to as a „working river‟. This study aims to determine the current state of ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers and to establish trends between current and historical periods for the evaluation of changing trends in ecological integrity. Abiotic (driver) and biotic (responder) indicator components were used in order to identify and monitor any changes in the surrounding environment as well as to determine the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers. Driver components include water quality, sediment grain size, moisture and organic content as well as habitat state, whereas responder components involve macroinvertebrates and fish assemblages. Two surveys were carried out; one during the low-flow period (5-11 August 2011) and the other during the high-flow period (20-28 March 2012). Current data and findings together with historical data from 1999 to 2010 were used to establish trends of selected driver and responder components. Water quality variables selected include general variables such as water temperature, chemical oxygen demand (COD), electrical conductivity (EC), pH and total alkalinity (TAL) as well as salts, nutrients and toxics. These variables provide indications as to the state of the water-quality component of this study. The Target Water Quality Requirements (TWQR) as developed by the Department of Water Affairs and Forestry for domestic use (Volume 1) and Aquatic Ecosystems (Volume 7) were used to evaluate the quality of the water sampled in this study. The water quality as well as quantity was also compared to historical data obtained from previous studies that have been done for the same study area. The sediment analyses were performed according to the protocol set out by the United States Environmental Protection Agency. Habitat availability, diversity and state were assessed by means of the Integrated Habitat Assessment System Version 2 (IHAS v 2) and the Index of Habitat Integrity (IHI). The water quality of the lower Amatikulu River was found to be in a slightly modified state with the majority of water quality parameters within the target values as set by the TWQG. Water quality parameters considered on the lower Thukela River such as water temperatures, oxygen levels, nutrient and salt loads occurred at elevated levels and were not within the TWQG requirements. The water quality of the Thukela River wasconsidered to be in a modified state which may cause negative impacts on the structure and function of the river, while the water quality of the lower Umvoti River was seriously modified. Sediment analyses revealed that the organic content of the Lower Amatikulu, Thukela and Umvoti Rivers was low. Sediment grain-size distributions are dominated by well-sorted larger soil grain-sizes (>500 μm) which is not ideal for the biodiversity. This is an indication that erosion and transportation are taking place in the Amatikulu, Thukela and Umvoti Rivers. The removal of riparian vegetation by agricultural activities and water abstraction contributes to the habitat deterioration as well as erosion and transportation of sediments that occurs in lower Amatikulu, Thukela and Umvoti Rivers. The use of macroinvertabrates as biological indicators in the determination of the ecological integrity, state or health of lotic ecosystems is globally well established. The South African Scoring System, version 5 (SASS 5), the Macroinvertebrate Response Assessment Index (MIRAI) and multivariate statistical analyses were implemented in order to determine the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers. Results revealed that the SASS 5 integrity classes were generally one class higher than the integrity classes of MIRAI. SASS 5 and MIRAI integrity classes of the Amatikulu River ranged from natural (Class A) to largely modified (Class D/E) while the Thukela and Umvoti rivers ranged from natural to seriously modified (Class E/F). Fish assemblages are commonly used as key indicators to describe the ecological state of aquatic ecosystems. Methods used to sample fish included electronarcosis and a 5m wide 12mm meshed seine net. The Fish Response Assessment Index (FRAI) and multivariate statistical analyses were implemented in order to determine the ecological integrity of the lower Amatikulu, Thukela and Umvoti rivers. Results revealed that the automated FRAI integrity classes were constantly lower than the adjusted FRAI integrity classes. Automated and adjusted FRAI integrity classes of the Amatikulu River ranged from largely natural (Class B) to largely modified (Class D) while the Thukela and Umvoti rivers ranged from natural (Class A) to seriously modified (Class E/F). The current ecological integrity of the lower Amatikulu River was found to be in a largely natural, with few modifications (Class B) state. The Thukela River was found to be in a moderately modified (Class C) state while the Umvoti River was found to be in a largely modified (Class D) state. The trends in ecological integrity of the selected driver components which include water quality, sediment and habitat availability fluctuated noticeably. The general trend in water quality of the lower Amatikulu, Thukela and Umvoti Rivers slightly recovered towards 2012. Sediment analyses revealed that the sediment grain-size distribution as well as the moisture and organic contents generally remained stable. There was a decline in the general state of habitat integrity towards 2012. As a result of the decline in the habitat ecological integrity the ecological integrity of macroinvertebrates also slightly declined towards 2012. However, a noticeable improvement in the ecological integrity of fish assemblages was observed towards 2012. To conclude, the ecological integrity of water quality and fish assemblages improved towards 2012, while habitat and macroinvertebrates deteriorated and sediment stayed the same. The general and overall state of ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers did not deteriorate nor did it improve, but rather it stayed the same. Impacts on the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers include a multitude of different sources. To prevent the current ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers from deteriorating further, a collective effort involving all parties is essential. / MSc (Zoology), North-West University, Potchefstroom Campus, 2013
42

Die antropometriese sprong- en vloeritem-prestasiedeterminante van jong dogtergimnaste / Annelize Willemse

Willemse, Annelize January 2006 (has links)
Although the available literature mentions a variety of anthropometric performance determinants for gymnastics, no one has until now made an attempt to determine the performance determinants of more advanced, young, South African (SA), female gymnasts. The purposes of this study were, therefore, firstly to determine the anthropometric variables that differ significantly @ 5 0,05) between successful and less successful young, SA, female gymnasts in the vault and floor item and secondly, to determine the anthropometric variables that contribute to the performance of young, SA, female gymnasts in the vault and floor item. Twelve young, female gymnasts (13,39 f 2,14 years) from a gymnastics club in the North-West Province of South Africa participated in this study. Only gymnasts who participated at level 6-9 and junior as well as senior olynlpic level were selected to participate in this study. Sixty one anthropometric variables were measured on the dominant side of the body according to the methods of Norton et al. (1996). Firstly, the descriptive statistics (means and standard deviations) of the gymnastics population were calculated. This was followed by an analysis which intended to arrange the gymnasts in a ranking order according to the vault and floor performances (marks) that were reached during the South African Gymnastics Championships. Due to differences in the participation level, data was normalised by making use of correction factors. Independent t-tests and effect sizes revealed that the gymnasts who obtained the highest marks (top 5) during the execution of the vault and floor item during the South African Gymnastics Championships had statistical and practical significantly (p 5 0,05) larger relaxed and flexed upper arm, wrist and ankle circumferences as well as mesomorph values than the less successful gymnasts. The cluster analysis-reduced variables were used to perform a forward, stepwise multiple regression analysis which showed that flexed upper arm (53,93%) and chest circumference (3,6996); midstillion dactillion (12,38%), trochanterion-tibia1 lateral (5,77%) and foot length (1 1,50%); fat percentage (8,93%), ectomorphy (l,96%), bideltoied breadth (1,54%), triceps skinfold (0,23%) and iliospinal box height (0,07%) contributed 100% to the variance in gymnasts' vault performances. Bi-trochanterion- (34,86%), femur- (17,07%) and bi-deltoied breadth (4,93%); front thigh skinfold (19,71%); fat percentage (7,68%); acromial-radial (4,09%) and foot length (0,05%) as well as waist- (6,68%), chest- (2,92%) and gluteal thigh circumference (2;02%) were the anthropometric variables which contributed 100% to the variance in gymnasts' floor performances. Flexed upper arm circumference, fat percentage, ectomorphy, iliospinal box height and bitrochanterion and femur breadth as well as gluteal thigh circumference and foot length were, however, the only anthropometric variables which contributed significantly to gymnasts' vault and floor performances, respectively. The conclusion that can, therefore, be drawn is that larger upper arm and upper body circumferences; hand, foot, upper and total leg lengths; triceps skinfolds, fat percentages and ectomorphy as well as larger limb and torso circumferences; waist breadths; fat percentages and front thigh skinfolds as well as upper arm and foot lengths are the respective, important anthropometric vaulting and floor performance determinants for young, South African, female gymnasts and should be included in the sport scientific testing protocols of gymnasts. / Thesis (M.Sc. (Human Movement Science))--North-West University, Potchefstroom Campus, 2007.
43

Die antropometriese sprong- en vloeritem-prestasiedeterminante van jong dogtergimnaste / Annelize Willemse

Willemse, Annelize January 2006 (has links)
Although the available literature mentions a variety of anthropometric performance determinants for gymnastics, no one has until now made an attempt to determine the performance determinants of more advanced, young, South African (SA), female gymnasts. The purposes of this study were, therefore, firstly to determine the anthropometric variables that differ significantly @ 5 0,05) between successful and less successful young, SA, female gymnasts in the vault and floor item and secondly, to determine the anthropometric variables that contribute to the performance of young, SA, female gymnasts in the vault and floor item. Twelve young, female gymnasts (13,39 f 2,14 years) from a gymnastics club in the North-West Province of South Africa participated in this study. Only gymnasts who participated at level 6-9 and junior as well as senior olynlpic level were selected to participate in this study. Sixty one anthropometric variables were measured on the dominant side of the body according to the methods of Norton et al. (1996). Firstly, the descriptive statistics (means and standard deviations) of the gymnastics population were calculated. This was followed by an analysis which intended to arrange the gymnasts in a ranking order according to the vault and floor performances (marks) that were reached during the South African Gymnastics Championships. Due to differences in the participation level, data was normalised by making use of correction factors. Independent t-tests and effect sizes revealed that the gymnasts who obtained the highest marks (top 5) during the execution of the vault and floor item during the South African Gymnastics Championships had statistical and practical significantly (p 5 0,05) larger relaxed and flexed upper arm, wrist and ankle circumferences as well as mesomorph values than the less successful gymnasts. The cluster analysis-reduced variables were used to perform a forward, stepwise multiple regression analysis which showed that flexed upper arm (53,93%) and chest circumference (3,6996); midstillion dactillion (12,38%), trochanterion-tibia1 lateral (5,77%) and foot length (1 1,50%); fat percentage (8,93%), ectomorphy (l,96%), bideltoied breadth (1,54%), triceps skinfold (0,23%) and iliospinal box height (0,07%) contributed 100% to the variance in gymnasts' vault performances. Bi-trochanterion- (34,86%), femur- (17,07%) and bi-deltoied breadth (4,93%); front thigh skinfold (19,71%); fat percentage (7,68%); acromial-radial (4,09%) and foot length (0,05%) as well as waist- (6,68%), chest- (2,92%) and gluteal thigh circumference (2;02%) were the anthropometric variables which contributed 100% to the variance in gymnasts' floor performances. Flexed upper arm circumference, fat percentage, ectomorphy, iliospinal box height and bitrochanterion and femur breadth as well as gluteal thigh circumference and foot length were, however, the only anthropometric variables which contributed significantly to gymnasts' vault and floor performances, respectively. The conclusion that can, therefore, be drawn is that larger upper arm and upper body circumferences; hand, foot, upper and total leg lengths; triceps skinfolds, fat percentages and ectomorphy as well as larger limb and torso circumferences; waist breadths; fat percentages and front thigh skinfolds as well as upper arm and foot lengths are the respective, important anthropometric vaulting and floor performance determinants for young, South African, female gymnasts and should be included in the sport scientific testing protocols of gymnasts. / Thesis (M.Sc. (Human Movement Science))--North-West University, Potchefstroom Campus, 2007.
44

Konfigurierbare Benutzerschnittstellen zur Vereinfachung formularbasierter Datenerfassung

Judt, Andreas January 2004 (has links) (PDF)
Zugl.: Karlsruhe, Univ., Diss., 2004
45

Modellgetriebene Konfiguration von Transaktionsdiensten in der komponentenbasierten Softwareentwicklung

Löcher, Sten January 2005 (has links)
Zugl.: Dresden, Techn. Univ., Diss, 2005
46

COBAMOS Endnutzerprogrammierung auf Basis nachrichtenbasierter Komponentenvernetzung

Töpfer, Guido Ralf January 2006 (has links)
Zugl.: Mainz, Univ., Diss., 2006
47

Ein generischer Ansatz zur vereinheitlichten strukturellen und funktionalen Modellierung evolutionärer Algorithmen /

Rummler, Andreas. January 2006 (has links)
Techn. Universiẗat, Diss., 2006--Ilmenau.
48

Externes Anwendungsmanagement : Organisation des Lebenszyklus komponentenbasierter, mobiler Anwendungen /

Lonthoff, Jörg. January 2007 (has links)
Zugl.: Darmstadt, Techn. Universiẗat, Diss., 2007.
49

Ausführung und Entwicklung adaptiver komponentenbasierter Anwendungen

Rasche, Andreas January 2008 (has links)
Zugl.: Potsdam, Univ., Diss., 2008
50

Automatische Konfiguration der Bewegungssteuerung von Industrierobotern /

Wenz, Michael. January 2008 (has links)
Zugl.: Karlsruhe, Universiẗat, Diss., 2008.

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