Modern space geodetic techniques are required to provide measurements of millimetre-level accuracy. A new fundamental space geodetic observatory for South Africa has been proposed. It will house state-of-the-art equipment in a location that guarantees optimal scientific output. Lunar Laser Ranging (LLR) is one of the space geodetic techniques to be hosted on-site. This technique requires optical (or so-called astronomical) seeing conditions, which allow for the propagation of a laser beam through the atmosphere without excessive beam degradation. The seeing must be at ~ 1 arc second resolution level for LLR to deliver usable ranging data. To establish the LLR system at the most suitable site and most suitable on-site location, site characterisation should include a description of the optical seeing conditions. Atmospheric turbulence in the planetary boundary layer (PBL) contributes significantly to the degradation of optical seeing quality. To evaluate astronomical seeing conditions at a site, a two-sided approach is considered – on the one hand, the use of a turbulence-resolving numerical model, the Large Eddy Simulation NERSC (Nansen Environmental and Remote Sensing Centre) Improved Code (LESNIC) to simulate seeing results, while, on the other hand, obtaining quantitative seeing measurements with a seeing monitor that has been developed in-house. / Dissertation (MSc)--University of Pretoria, 2012. / Geography, Geoinformatics and Meteorology / MSc / Unrestricted

Tato diplomová práce si klade za cíl návrh hybridního lokalizačního zařízení, které je schopno lokalizace uvnitř i vně budov. Lokalizace uvnitř budov je dosažena pomocí technologie Ultra Wideband a venkovní lokalizace je provedena pomocí kombinace technologie RTK GNSS a PPP pomocí open - source softwaru zvaného RTKLIB. První část textu se zaměřuje na vysvětlení používaných technologií a výběr nejpřesnější technologie pro venkovní lokalizaci. Druhá část se zaměřuje ma vývoj potřebného hardware a software finálního zařízení a na integraci systému pro venkovní lokalizaci do systému pro lokalizaci vnitřní. Výstupem práce je plně funkční zařízení, které je schopné plynulé lokalizace uvnitř i vně budov. Funčnost celého zařízení je dokázána na finálních testech uskutečněných ve vnitřních i venkovních prostorách. Na závěr také práce zmiňuje možná vylepšení celého zařízení, která mohou být v budoucnu provedena.

Unsocialized stray dogs live unrestrained in urban areas, having limited to no direct contact with humans. Aggressive behaviour towards humans leads to their apprehension to shelters, where they tend to stay permanently. This study aimed to determine if unsocialized stray dogs could be rehabilitated and develop the social skills needed for adoption. Six unsocialized stray dogs (Group Stray) and 12 socialized dogs (C1: Control Group 1, n=6; C2: Control Group 2, n=6) housed in a shelter were selected. Stray and C2 dogs went through two training phases: social rehabilitation towards humans and leash training. Sociability towards humans and behaviour on a leash were tested in all groups following Valsecchi et al. (2011). Sociability Tests (ST) and Leash Tests (LT) were conducted before any intervention (ST1), after sociability training (ST2, LT1) and after leash training (ST3, LT2). Training sessions and tests were video recorded and posteriorly analysed by four observers. Results showed that for Stray, but not for C1 and C2, there was a significant increase in sociability from ST1 to ST3. Moreover, for Stray Group there was a significant decrease in the frequency of fear-related behaviours between ST1 and ST3. For leash behaviour, no significant changes were found from LT1 to LT2 for neither group. However, there was considerable individual variation, as not all strays overcame their extreme fear towards humans. These findings suggest that dog­–human interactions can be improved through training for dogs who do not show extreme fear and/or aggression towards humans.

The African wild dog, second most endangered carnivore in Africa, has a well-developed, highly cooperative pack system. The usual structure of a pack consists of a dominant breeding pair, the alpha male and female, several subordinates, non-breeding adults and dependent offspring. Domestic dog microsatellites were used to study the parentage in three packs and confirm that more than one dog, including the subordinate males, can sire pups within a litter as previously suggested. The study was performed on two isolated populations of wild dogs in the North West Province of South Africa. In Madikwe Game Reserve, skin samples from 47 dogs were obtained by means of biopsy darts (adults) and skin slivers taken from the ear (subadults) and stored in absolute ethanol. In Pilanesberg National Park, blood samples from 18 captured dogs were collected in EDTA blood tubes. The wild dogs were photographed and individually identified according to coat patterns. Behavioural data to determine ranking were collected from all three packs. DNA was extracted from collected samples using proteinase-K digestion followed by isolation of DNA with phenol/chloroform/isoamyl alcohol. A total of 16 microsatellite loci that consistently amplified and appeared to be polymorphic in wild dogs, were used. Polymerase Chain Reaction (PCR) was performed using two panels of microsatellite loci in multiplex reactions. An amount of 1 µl of PCR product was loaded on to the 3130 XL Genetic Analyser with Genescan 500 LIZ (Applied Biosystems) size standard and analysed using STRand (Board of Regents, University of California) software program. CERVUS 2.0 software was used to calculate allele frequencies, expected and observed heterozygosity, frequency of null alleles, polymorphic information content and exclusion probabilities for parentage assignment. Parentage verification was also performed manually. The parentage analysis revealed that at least one pup was not sired by the alpha male in each of the five litters studied. Although previous studies suggested that the alpha male sires the majority of offspring in the pack, our results confirm that subordinate males commonly sire pups with the alpha female if and when the opportunity arises. This is possibly a mechanism to decrease the effects of inbreeding. / Dissertation (MSc (Veterinary Sciences))--University of Pretoria, 2006. / Production Animal Studies / unrestricted

Unknown wireless devices that use receiver architectures with a mixer may be detected and located using stimulated emissions. Transmitting a known stimulation signal and correlating leaked mixer products allows measurement of the TOF and thus range. The FRFT improves the detection of the stimulated emissions by compressing the energy of the stimulated emissions to a single axis value. The stimulation signal has many parameters that may be optimized for maximum detection distance or minimum range error or somewhere in between. The primary limiting factor for the parameters is the processing time, as the algorithm to compute the discrete FRFT is computationally intensive at the time of this report. The tests performed in this investigation achieved 45+meters detection distance with < 3 meters of range error, with potential for farther detection distance.

Since March 2006 the Institute of Meteorology in Leipzig (LIM) is owner of a commercial Mini-SODAR. The Mini-SODAR is very small in size and therefore mobile. It can be set up with low effort in short time at any place. The first testmeasurement was operated in June 2006 at the boundary layer field site Falkenberg that belongs to the Meteorological Observatory Lindenberg (MOL) of the German Meteorological Service (DWD) and was parallel accompanied by the measurement of a windtower and a Doppler-SODAR. The results of this six-hour-measurement are presented here. A statistical comparison between Mini-SODAR, tower data and Doppler-SODAR was performed. Also backscatter intensity and profile data from Mini-SODAR were analysed and interpreted. / Seit März 2006 ist das Leipziger Institut für Meteorologie (LIM) in Besitz eines kommerziellen Mini-SODARs. Das Mini-SODAR ist auf Grund seiner Größe sehr mobil und lässt sich unter geringem Aufwand schnell an einem beliebigen Standort aufbauen. Die erste größere Testmessung und gleichzeitig Vergleichsmessung dieses Gerätes mit einem Windmast und einem Doppler-SODAR fand im Juni 2006 auf dem Grenzschichtmessfeld in Falkenberg statt, welches zum Meteorologischen Observatorium (MOL) des Deutschen Wetterdienstes (DWD) gehört. Die Auswertung dieser 6-stündigen Messung wird hier vorgestellt. Es wurde ein statistischer Vergleich zwischen Mini-SODAR, Windmast und Doppler-SODAR durchgeführt. Weiterhin wurden das Sodargramm und die gemessenen Profildaten des Mini-SODARs untersucht und interpretiert.

This thesis examines the role of grandchildren's existence in the retirement timing decision- making process of grandparents. Previous literature has focused mostly on other aspects of retirement and potential causes that can affect its timing. Using the Two-Stage least squares estimation on the SHARE dataset, representing 17 European countries and Israel, we estimate the desired effect with respect to various data limitations (age groups, gender, child existence). Residential proximity is used as the instrument for estimation. Having at least one grandchild yields a statistically significant result that increases on average the likelihood of retirement by 19% when compared to a non-grandparent while holding other factors constant. As a secondary outcome, the estimated effect of an additional child on retirement likelihood is negative. JEL Classification C36, C51, J26 Keywords grandchild, retirement, Instrumental variable, SHARE, IV, wide-ranging data, 2SLS Title The impact of grandchildren on retirement timing: evidence from SHARE data

There are many applications for which small unmanned aerial vehicles (SUAVs) are well suited, including surveillance, reconnaissance, search and rescue, convoy support, and short-range low-altitude perimeter patrol missions. As technologies for microcontrollers and small sensors have improved, so have the capabilities of SUAVs. These improvements in SUAV performance increase the possibility for hazardous missions through mountainous and urban terrain in the successful completion of many of these missions. The focus of this research was on remote terrain navigation and the issues faced when dealing with limited onboard processing and limited payload and power capabilities. Additional challenges associated with canyon and urban navigation missions included reactive path following, sensor noise, and flight test design and execution. The main challenge was for an SUAV to successfully navigate through a mountainous canyon by reactively altering its own preplanned path to avoid canyon walls and other stationary obstacles. A robust path following method for SUAVs that uses a vector field approach to track functionally curved paths is presented along with flight test results. In these results, the average tracking error for an SUAV following a variety of curved paths is 3.4~m for amplitudes ranging between 10 and 100~m and spatial periods between 125 and 500~m. Additionally, a reactive path following method is presented that allows a UAV to continually offset or bias its planned path as distance information from the left and right ranging sensors is computed. This allows the UAV to to center itself between potential hazards even with imperfect waypoint path planning. Flight results of an SUAV reactively navigating through mountainous canyons experimentally verify the feasibility of this approach. In a flight test through Goshen Canyon in central Utah, an SUAV biased its planned path by 3 to 10~m to the right as it flew to center itself through the canyon and avoid the possibility of crashing into a canyon wall.

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