Since the 1980’s horizontal drilling has been a game-changing technology as it allowed the oil and gas industry to produce from reservoirs previously considered marginal or uneconomic. However, while it is considered a mature technology, directional drilling is still done in a reactive fashion. Although many directional drillers are quite adept at predicting the directional response of the bottomhole assembly (BHA) in a given well, the ability to manage all of the drilling parameters on a foot by foot basis while accurately predicting the effects of each parameter is impossible for the human brain alone. Given current rig rates, any amount of increased slide time and its reduced ROP which occurred due to poorly predicted directional response can result in a significant economic impact. There exist many measured parameters or system inputs which have been proven to affect the directional response of a drilling system. One parameter whose effect has not been investigated is mechanical specific energy or MSE. MSE is measure of how efficient the drilling process is in relation to rate of penetration. To date, MSE has primarily been used with for vibration analysis and rate of penetration optimization. The following dissertation covers research into the effect of MSE on the overall wellbore direction change or dog-leg severity. Using published experimental data, a correlation was developed which shows a clear relationship between the dog-leg severity, rate of penetration (ROP) and MSE. The correlation requires only a few hundred feet of drilling before it is able to be tuned to match an individual well’s results. With minimal tuning throughout the drilling of a well, very good results can be obtained with regards to forecasting dog-leg severity as the wellbores were drilled ahead. The correlation was tested using data from multiple, geo-steered wells drilled in a shale reservoir. The analysis of the correlation using real-world data proved it to be a robust and accurate method of predicting the magnitude of dog-leg severity. The use of this correlation results in a smoother wellbore, drilled with a faster overall ROP with a better chance of staying within the geologic targets.

Horizontal Directional Drilling (HDD) has been used internationally for the trenchless installation of utility conduits and other infrastructure. However, the mud loss problem caused by excessive mud pressure in the borehole is still a challenge encountered by trenchless designers and contractors, especially when the drilling crosses through cohesionless material. Investigation of mud loss problem is necessary to apply HDD with greater confidence for installation of pipes and other infrastructure. The main objectives of this research have been to investigate the maximum allowable mud pressure to prevent mud loss through finite element analysis and small scale and large scale laboratory experiments. The recent laboratory experiments on mud loss within sand are reported. Comparisons indicate that the finite element method provides an effective estimation of maximum mud pressure, and “state-of-the-art” design practice- the “Delft solution” overestimates the maximum mud pressure by more than 100%. The surface displacements exhibit a “bell” shape with the maximum surface displacement located around the center of the borehole based on the data interpreted using Particle Image Velocimetry (Geo-PIV) program. A parametric study is carried out to investigate the effect of various parameters such as the coefficient of lateral earth pressure at rest K0 on the maximum allowable mud pressure within sand. An approximate equation is developed to facilitate design estimates of the maximum allowable mud pressure within sand. A new approach is introduced to consider the effects of coefficient of lateral earth pressure at rest K0 on the blowout solution within clay. The evaluations using finite element method indicate that the new approach provides a better estimation of the maximum allowable mud pressure than the “Delft solution” in clay when initial ground stress state is anisotropic (K0 ≠1). Conclusion of this research and suggestions on future investigation are provided. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2009-01-14 12:23:35.069

<p>High-spin states in the oblate deformed odd-odd thallium nucleus ( ) 109 190 81 Tl have been investigated through the reaction 175Lu(20Ne, 5n)190Tl at a beam energy of 115 MeV. The gamma rays emitted from 190Tl nucleus were detected with Ge detectors using the AFRODITE array at iThemba LABS, South Africa. Gamma-gamma coincidence data were obtained and used to construct the level scheme. In this work, Directional Correlations from Oriented (DCO) state ratios and linear polarization anisotropies were measured in order to deduce spin and parity of energy levels in the decay scheme. It was possible to determine the spin and parity of two additional signature-partner bands which decay to the ground-state band.</p>

Thesis (Ph. D.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references. / Also available by subscription via World Wide Web / xi, 102 leaves, bound ill. 29 cm

Equipment of many different types is operated by multiple control levers located in close proximity to each other. Selecting the wrong control, or moving the correct control in the wrong direction, has the potential to cause serious injury (e.g. Burgess-Limerick & Steiner, 2006). The objectives of this research were to use a virtual reality simulation of a generic equipment control task to examine: (1) the consequences of shape coding on selection error rate and reaction time; (2) the effect of mirror versus place control layout on shape coding and reaction time when the side to which the controls levers were placed changed; and (3) the consequences of different directional control-response relationships in the horizontal and vertical plane on direction errors and reaction time. Three experiments were completed by a total of 168 participants. Participants were presented with two identical virtual octagonal rods that could elevate/lower, slew left/right, extend/retract and change colour red/blue. One of the images was computer controlled and the other was controlled by four control levers, mounted on a stand, which could be altered in orientation and effects. The task for the participants involved replicating the movement of the computer controlled image by manipulating the four levers positioned on their right or left side. Each participant completed ten blocks of 16 trials, with each trial requiring sequential movements of each of the four control levers. Twenty-four participants completed Experiment One, using horizontal controls and a control-response relationship in which moving each of the horizontal control upwards caused the stimulus to elevate, slew right; extend; or change its colour to red, referred to as control-response relationship 1 (CRR1). Each participant was randomly assigned to start with shape or non-shape coded controls, changing to the reversed coding condition after five blocks. Fewer selection errors occurred in shape coded conditions in the first five blocks, although the difference was not statistically significant. Reaction times decreased as a function of block, and were higher in shape coded trials. There were very few elevation directional errors. Slew and extension directional errors were less likely when there was a spatial correspondence between the movement of the control and the response. Horizontal controls, and the same set of control-response relationships was used in Experiment Two. Each of the 48 participants was randomly assigned to start the experiment with the controls located on their left or right side, whether to complete the experiment with shape or non-shape coded controls, and finally whether to transfer sides to a mirror or place arrangement after five blocks. An effect of coding on selection errors occurred only in the block immediately following a change of sides. However, the effect of coding on selection errors was only seen among participants transferring to a place arrangement, and there were no differences in the number of selection errors between transfer conditions for either coding conditions, nor were there any differences in reaction times between transfer conditions. Reaction times decreased as a function of block, and longer reaction times were measured in the shape coded trials. An advantage of a mirror arrangement when changing sides was suggested when controls were not shape coded, however no advantage was evident when the controls were shape coded. Ninety-six participants completed Experiment Three. Controls were horizontal or vertical, and data were collected for two directional control-response relationship conditions in each orientation: horizontal CRR1; horizontal CRR2 "up" = lower, slew left, retract and blue; vertical CRR1 "away from operator" = elevate, slew right, extend and red; and vertical CRR2 "away from operator" = lower, slew left, retract and blue. Each participant was randomly assigned to complete the experiment with the controls horizontal or vertical, using shape or non-shape coded controls, in the CRR1 or CRR2 condition. The effect of shape coding on reducing the rate of control selection errors in the first block was not significant, however reaction times for correct movements were consistently longer for shape coded conditions. Elevation directional errors in the horizontal CRR1 condition was minimised in all cases, regardless of whether the control movement and the response were spatially corresponding or not. Similar results were seen for the extension control in the horizontal and vertical CRR1 conditions. In other situations, directional errors were less likely when there was spatial correspondence between the movement of the control lever and the response. While only limited evidence was found to indicate that shape coding reduced the probability of selection errors being made in this situation, the observation that the time taken to make correct responses was consistently longer in the shape coded conditions could be interpreted from an information processing, stage model, perspective as indicating that the additional information available in the shape coding was being processed during the decision making stage. It may be that the effect on selection error rate would have been larger if more controls were involved. The results indicate that directional compatibility effects are not as straightforward as the current standards and guidelines suggest. In most, but not all, situations it is important to ensure that control-response relationships correspond spatially.

Doctor of Philosophy / Collective actions of large animal groups result in elaborate behaviour, whose nature can be breathtaking in their complexity. Social organisation is the key to the origin of this behaviour and the mechanisms by which this organisation occurs are of particular interest. In this thesis, these mechanisms of social interactions and their consequences for group-level behaviour are explored. Social interactions amongst individuals are based on simple rules of attraction, alignment and orientation amongst neighbouring individuals. As part of this study, we will be interested in data that takes the form of a set of directions in space. In Chapter 2, we discuss relevant statistical measure and theory which will allow us to analyse directional data. These statistical tools will be employed on the results of the simulations of the mathematical models formulated in the course of the thesis. The first mathematical model for collective group behaviour is a Lagrangian self-organising model, which is formulated in Chapter 3. This model is based on basic social interactions between group members. Resulting collective behaviours and other related issues are examined during this chapter. Once we have an understanding of the model in Chapter 3, we use this model in Chapter 4 to investigate the idea of guidance of large groups by a select number of individuals. These individuals are privy to information regarding the location of a specific goal. This is used to explore a mechanism proposed for honeybee (Apis mellifera) swarm migrations. The spherical theory introduced in Chapter 2 will prove to be particularly useful in analysing the results of the modelling. In Chapter 5, we introduce a second mathematical model for aggregative behaviour. The model uses ideas from electromagnetic forces and particle physics, reinterpreting them in the context of social forces. While attraction and repulsion terms have been included in similar models in past literature, we introduce an orientation force to our model and show the requirement of a dissipative force to prevent individuals from escaping from the confines of the group.

Thesis (Ph.D.)--York University, 2006. Graduate Programme in Computer Science. / Typescript. Includes bibliographical references (leaves 266-281). Also available on the Internet. MODE OF ACCESS via web by entering the following URL: http://proquest.umi.com/pqdweb?index=0&did=1306835141&SrchMode=1&sid=4&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1195136081&clientId=5220

Thesis (Ph. D.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references.

Thesis (Ph.D.). / Written for the Dept. of Physics. Title from title page of PDF (viewed 2009/06/11). Includes bibliographical references.

Thesis (Ph. D.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Mechanical Engineering, 2009. / Includes bibliographical references.