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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.

A multichannel borehole radar for three dimensional imaging

Hargreaves, Jonathan January 1995 (has links)
No description available.


Berry, Frank Herman 27 May 2013 (has links)
Although the quantity surveyors had laid their claim to the building industry for more than a century, poor scientific knowledge analyses with reference to the professional communication capabilities and communication instruments in the construction industry still exists. The aim of this thesis is to measure the determinants of a communication maturity model in respect of the communication capabilities of the profession. The proposed most important determinants used were brought to light through research undertaken by the University of the Free State in collaboration with the Wirtschafts University in Vienna, Austria in 2005/6. The results of the survey indicate that respondents were positive with regard to professional communication in general. This can influence the construction industry with continuous advantages for the property development environment. The survey results indicate that the determinant contractual communication of the quantity surveyor is experienced the most positive. The determinant leadership communication of the quantity surveyor is experienced the least positive. A model of the most important determinants for effective communication was used to measure the maturity of the professionâs communication capabilities in the construction industry.


Burger, Michelle 23 July 2013 (has links)
The use of project management has expanded and is used in many industries. The generic component of project management across all industries without the necessary technical knowledge has been debated. This study investigates the knowledge base of construction project management and the need for industry specific knowledge. The study includes a literature and also empirical research section. The empirical study made use of interviews, a case study and questionnaires. A construction project management knowledge model was developed based on the research and research findings. The research findings suggest that a project manager in the built environment requires various types of knowledge â project management knowledge, industry specific knowledge and knowledge gained through experience. The project management knowledge includes the 13 areas from the construction extension to the PMBOK guide, the industry specific knowledge is divided into four main areas that are knowledge of construction science, knowledge of construction processes, knowledge of design processes and knowledge of financial cost factors and the knowledge through experience is gained through time spent working in the industry. The construction project management knowledge model aims to contribute to improving the project management environment, aiding in awareness of the various knowledge areas and subareas that are important and the NQF level that is suggested. This could contribute to sufficient education by creating awareness of the level of education a project manager in the built environment requires. Organisations could use the model as reference to determine which areas their project managers could improve on in order to develop and increase project management maturity in the organisation. The project management construction model also offers tertiary institutions a framework for syllabus planning of constructions project management courses. Further research is welcomed and may include improving the model, or using the model as foundation to develop a measuring instrument to determine the knowledge of a construction project manager.

Satellite laser ranging and the determination of earth rotation parameters

Moore, Terry January 1986 (has links)
Over recent years considerable advances have taken place in the field of space geodesy, resulting in a number of highly precise global positioning techniques. The increased resolution of many of the scientific products from the new observational techniques has stimulated the interest of not only geodesists but also geophysicists. Furthermore, their potential to determine the orientation of the earth's axis of rotation (polar motion) and the variations of the rate of rotation of the earth about that axis, was recognised by the scientific community. The result was the establishment of Project MERIT, to intercompare these new observational techniques. Satellite Laser Ranging, a method of measuring the distance from a point on the earth's surface to an artificial satellite by means of timing the flight of a short pulse of laser light, is currently the most accurate available means of tracking near earth satellites. However, in order to reach the accuracy requirements of current geodetic applications dedicated satellites, such as the NASA LAser GEOdynamic Satellite (LAGEOS), must be tracked and specialised processing software must be used. This Thesis describes the basic theory behind the analysis of Satellite Laser Ranging Observations, with a special emphasis on the determination of earth rotation parameters (the polar motion and the variations in the rate of rotation). The development and testing, at Nottingham, of the Satellite Orbit Determination and Analysis Package Of Programs, SODAPOP, for the processing of laser range data, is described. The thesis also presents and discusses the results of the analysis of laser range observations the LAGEOS satellite, from the short and main campaigns of project MERIT.

Curriculum and pedagogical developments within university surveying & geomatics courses

Young, Garfield Osbourne January 2013 (has links)
In the last three decades there have been major changes in how surveying is practiced, and what surveyors have been trained and educated to do with the new expertise that technological advancements offer. Within surveying communities it is generally acknowledged that the changes in the profession have brought about an urgent need for change in educational programmes if they are to have relevance to contemporary practice. The thesis reports on a research study which explored the nature and impact of the educational strategies used in university surveying courses. The study employed a nested case study approach at two levels. Firstly, fifteen initial case studies of university programmes from thirteen countries provided a broad perspective of surveying education across the world. Secondly, two of these programmes were selected for in-depth comparative case studies to provide deeper understandings of the educational systems in two distinct contexts. The inquiry methods for the initial case studies included documentary analysis and interviews of senior academics and representatives of professional surveying bodies. For the two in-depth case studies, the inquiry methods included observations of pedagogical activities, focussed group discussions and interviews of university staff and students as well as professional surveyors. The interviews were recorded and thematically analysed. Some concepts from Bourdieu’s theory of practice were useful in coming to understandings about the interrelationship between the field of surveying education and the field of surveying practice. The study identified tensions and prospects within and between the programmes studied and between them and the profession. The key issues that emerged were: the predominance of highly discipline specific curricula with some indication of a shifting to a more broad-based education; tensions between industry expectations and the academic focus; a high level of interest in the university courses from the profession and uncertainty about the real meaning of geomatics and its relevance to local surveying communities. The findings have critical implications for how surveying/geomatics educational courses are developed in the future. The empirical evidence led to the development of a proposed improved model for contemporary surveying/geomatics education.

The use of targets to improve the precision of mobile laser scanning

Abdulrahman, Farsat Heeto January 2013 (has links)
A Mobile Laser Scanning System (MLSS) is a kinematic platform combining different sensors, namely: GPS, IMU and laser scanner. These sensors are integrated and synchronised to a common time base providing 3D geo-referenced data. MLSS is used in several areas; such as 3D urban and landscape modelling for visualisation in planning and road design, simulations for environmental management, and to support land use decision-making. The accuracy of 3D geo-referenced points, achieved via Mobile Laser Scanning (MLS) under normal conditions, can reach the level of 3cm. However, this accuracy tends to be degraded in urban areas, because of trajectory errors of the laser scanner (IMU drift due to the limited availability of GPS signal). This, also, can be attributed to the difficulty of matching natural features in the point cloud. Previous researches have tried to overcome the problems in urban laser scanning by focusing on enhancing the performance of the navigation system (NGS). This can be costly and may not achieve the high accuracy level required for some engineering application. When the navigation solution is degraded, the accuracy of the point cloud results will be degraded. Using different data sources is another way to improve accuracy in urban areas. For example using airborne LiDAR, terrestrial imagery, and unmanned aerial vehicle (UAV) but these are very time consuming as well as costly compared to MLS systems. Targets are used in a number of ways in MLS and are often chosen from natural detail points. These can be difficult to define, particularly when high accuracy requirements need to be met, for example, when matching scans together or fitting scans to existing surveys as used in this project, and calibrating the system. The accuracy of MLS in the urban area was tested using three methods, namely ground control points (GCPs), surface to surface comparing, and additional source of data. Also, the effect of range, incidence angle (IA), resolution and brightness on different types of targets (sphere, cone, pyramid and flat target) was studied to explore the optimal target design. Moreover, an algorithm for automatic target detection was developed to detect the optimal target. Then, for each target in the point cloud, the centre/apex was calculated using least squares surface fitting. Tests show that the accuracy of 3D coordinates, obtained from MLS in an urban area is about 2-5 cm. Tests also show that using targets with MLS can improve the quality of results reaching 5 mm levels of accuracy even in the urban area, based on the use of check points to assess the quality and reliability of the outputs Almost all work on this project was carried out using the software packages available at the Nottingham Geospatial Institute (NGI) and MLS data provided by 3D Laser Mapping Ltd. (3DLM). Two terrestrial laser scanners, namely: HDS 3000 and Faro Focus3D have been used for testing the designed targets. The findings of this research will contribute easy, cost effective and improved accuracies in MLS data. This enhances usefulness in applications, such as change detection, deformation monitoring, cultural heritage and the process of 3D modelling, particularly in urban areas.

Development of azimuth dependent tropospheric mapping functions, based on a high resolution mesoscale numerical weather model, for GNSS data processing

Orliac, Etienne J. January 2009 (has links)
This thesis is dedicated to the development of two new tropospheric mapping functions for GNSS data processing, based on a high resolution mesoscale numerical weather model (NWM). NWMs have proven to be beneficiary in the processing of GNSS and VLBI data, both for deriving mapping functions and for providing a priori information such as zenith hydrostatic delay (ZHD). The mapping functions derived here make a greater use of the NWM information than the mapping functions currently recommended by the International GNSS Service. In addition to using a single vertical pro¯le at the site in order to derive mapping functions under the assumption of an azimuthally symmetric atmosphere, the NWM was also ray traced every thirty degrees in azimuth. This way, a complete volume of the atmosphere is sensed, and better modelling is expected if the NWM does indeed provide an accurate representation of the atmosphere, by accounting for azimuthal variations. An emphasis was put in this thesis on assessing the mathematical models used to vertically interpolate meteorological information, as they play a key role in computing the refractivities in the ray tracing algorithm. Error sources were identified and quantified. As expected, water vapour is the major source of error. However, the results showed that the model used for the total pressure induced a systematic bias. To derive an azimuth dependent mapping function, the Marini model traditionally used had to be left in favor of a cubic spline interpolation (CSI). This new approach was validated by comparing the performance of the new azimuthally symmetric mapping functions against the updated Vienna mapping functions (VMF1), the best mapping functions currently available. Similar positioning performances were obtained, therefore validating the CSI based approach. The performance of new azimuth dependent mapping functions (AMF) in handling the troposphere asymmetry were compared to those obtained when estimating horizontal tropospheric gradients with an azimuthally symmetric mapping function. Results show a good agreement in the modelling of the asymmetry, and that estimating gradients is justified. The gradient solution performed better overall, although it failed for some sites, and better inter-station consistency was obtained with the AMF. This thesis also investigated the role of the tropospheric modelling in the retrieval of the atmospheric pressure loading (APL) in GNSS data processing, which is now part of the IGS 2008 recommendations. The results show that differential height time series obtained with different tropospheric modelling can correlate with the APL signal to a level up to 0.7. In other words, the choice of tropospheric modelling strategy does greatly influence the retrieval of the APL.

Selection of surveying methods

Harris, Robert James January 2011 (has links)
Digitized by Kansas Correctional Industries

En inblick i en byggmätares vardag vid LKAB:s anläggning i Kiruna

Brännlund, Therese January 2007 (has links)
<p>Målet med detta examensarbete var att jag skulle omvandla mina teoretiska kunskaper inom mätning till praktiska färdigheter. Resultatet blev denna skriftliga rapport, en muntlig presentation och en poster.</p><p>Jag gjorde mitt examensarbete hos Svenska Mätcenter AB. Projektet hette KK4 och innefattade kulsinterverk, utfrakt och bangård på LKAB:s anläggning i Kiruna. Svenska Mätcenter AB var även utsättare nere i gruvan där LKAB drev en ny väg. Under mitt examensarbete var jag runt på alla delarna av projektet för att lära mig så mycket som möjligt.</p><p>När mina fem veckors praktik var över hade jag lärt mig en hel del om mätning i allmänhet och byggmätning i synnerhet. De områden där mina kunskaper ökade mest var inom toleranser, kvalitetssäkring, tunnel- och gruvmätning och maskinstyrning.</p><p>En relationsritning över bultgrupperna vid drivstationen skapades för att kontrollera att de låg inom toleranserna.</p><p>Den slutsats jag har dragit är att all kunskap man får inom skolan är bara en bråkdel av vad man kommer att lära sig när man börjar jobba. Men det är en bra bas att stå på.</p>

Wireless Data Transmission System for Real-time 3D Geophysical Sensing

Viggiano, David Anthony 01 January 2007 (has links)
A wireless data transmission system was developed and implemented for use in real-time 3D geophysical sensing. Server and Client applications were designed to run on a stationary computer and a mobile computer attached to the geophysical sensor, respectively. Several methods for optimizing communication over wireless networks using commonly available hardware were tested and compared, and a scheme for varying the size of transmissions in accordance with the recent performance of the wireless network was chosen. The final system was integrated with a 3D Ground Penetrating Radar (GPR) system and tested in a field experiment that spanned two weeks and involved the acquisition of 16 data volumes. The system performed successfully throughout the experiment and provided necessary feedback to assist in the error-free acquisition of all data volumes. Future development of the system is discussed in order for the system to support an automated wireless geophysical sensor network with multiple client sensors moved around the survey area by automated robots.

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