Automotive applications of high precision GNSS

This thesis aims to show that Global Navigation Satellite Systems (GNSS) positioning can play a significant role in the positioning systems of future automotive applications. This is through the adoption of state-of-the-art GNSS positioning technology and techniques, and the exploitation of the rapidly developing vehicle-to-vehicle concept. The merging together of these two developments creates greater performance than can be achieved separately. The original contribution of this thesis comes from this combination: Through the introduction of the Pseudo-VRS concept. Pseudo-VRS uses the princples of Network Real Time Kinematic (N-RTK) positioning to share GNSS information between vehicles, which enables absolute vehicle positioning. Pseudo-VRS is shown to improve the performance of high precision GNSS positioning for road vehicles, through the increased availability of GNSS correction messages and the rapid resolution of the N-RTK fixed solution. Positioning systems in the automotive sector are dominated by satellite-based solutions provided by GNSS. This has been the case since May 2001, when the United States Department of Defense switched off Selective Availability, enabling significantly improved positioning performance for civilian users. The average person most frequently encounters GNSS when using electronic personal navigation devices. The Sat Nav or GPS Navigator is ubiquitous in modern societies, where versions can be found on nomadic devices such as smartphones and dedicated personal navigation devices, or built in to the dashboards of vehicles. Such devices have been hugely successful due to their intrinsic ability to provide position information anywhere in the world with an accuracy of approximately 10 metres, which has proved ideal for general navigation applications. There are a few well known limitations of GNSS positioning, including anecdotal evidence of incorrect navigation advice for personal navigation devices, but these are minor compared to the overall positioning performance. Through steady development of GNSS positioning devices, including the integration of other low cost sensors (for instance, wheel speed or odometer sensors in vehicles), and the development of robust map matching algorithms, the performance of these devices for navigation applications is truly incredible. However, when tested for advanced automotive applications, the performance of GNSS positioning devices is found to be inadequate. In particular, in the most advanced fields of research such as autonomous vehicle technology, GNSS positioning devices are relegated to a secondary role, or often not used at all. They are replaced by terrestrial sensors that provide greater situational awareness, such as radar and lidar. This is due to the high performance demand of such applications, including high positioning accuracy (sub-decimetre), high availability and continuity of solutions (100%), and high integrity of the position information. Low-cost GNSS receivers generally do not meet such requirements. This could be considered an enormous oversight, as modern GNSS positioning technology and techniques have significantly improved satellite-based positioning performance. Other non-GNSS techniques also have their limitations that GNSS devices can minimise or eliminate. For instance, systems that rely on situational awareness require accurate digital maps of their surroundings as a reference. GNSS positioning can help to gather this data, provide an input, and act as a fail-safe in the event of digital map errors. It is apparent that in order to deliver advanced automotive applications - such as semi- or fully-autonomous vehicles - there must be an element of absolute positioning capability. Positioning systems will work alongside situational awareness systems to enable the autonomous vehicles to navigate through the real world. A strong candidate for the positioning system is GNSS positioning. This thesis builds on work already started by researchers at the University of Nottingham, to show that N-RTK positioning is one such technique. N-RTK can provide sub-decimetre accuracy absolute positioning solutions, with high availability, continuity, and integrity. A key component of N-RTK is the availability of real-time GNSS correction data. This is typically delivered to the GNSS receiver via mobile internet (for a roving receiver). This can be a significant limitation, as it relies on the performance of the mobile communications network, which can suffer from performance degradation during dynamic operation. Mobile communications systems are expected to improve significantly over the next few years, as consumers demand faster download speeds and wider availability. Mobile communications coverage already covers a high percentage of the population, but this does not translate into a high percentage of a country's geography. Pockets of poor coverage, often referred to as notspots, are widespread. Many of these notspots include the transportation infrastructure. The vehicle-to-vehicle concept has made significant forward steps in the last few years. Traditionally promoted as a key component of future automotive safety applications, it is now driven primarily by increased demand for in-vehicle infotainment. The concept, which shares similarities with the Internet of Things and Mobile Ad-hoc Networks, relies on communication between road vehicles and other road agents (such as pedestrians and road infrastructure). N-RTK positioning can take advantage of this communication link to minimise its own communications-related limitations. Sharing GNSS information between local GNSS receivers enables better performance of GNSS positioning, based on the principles of differential GNSS and N-RTK positioning techniques. This advanced concept is introduced and tested in this thesis. The Pseudo VRS concept follows the protocols and format of sharing GNSS data used in N-RTK positioning. The technique utilises the latest GNSS receiver design, including multiple frequency measurements and high quality antennas

Low-Dose Dexamethasone Therapy from Infancy of Virilizing Congenital Adrenal Hyperplasia

Objective. To assess the growth and control of adrenal androgen secretion in children with virilizing congenital adrenal hyperplasia (CAH) treated with dexamethasone. Method. We examined doses used, control of adrenal androgen secretion, and growth and skeletal maturation of 8 children with CAH treated with dexamethasone beginning in infancy. Results. 3 boys and 5 girls with classical CAH (17-hydroxyprogesterone at diagnosis >20,000 ng/dL) were treated with dexamethasone beginning at diagnosis (<10 days of age). Patients were also treated with fludrocortisone and sodium chloride. The average initial medication dose was 0.1 mg (0.28 ± 0.015 mg/m2); all doses were given in the morning using a dosing syringe to administer a 0.1 mg/mL elixir. The children were treated for 6.5 ± 2.0 years over which time the change in bone age to chronological age ratio (ΔBA/ΔCA) was 0.9 ± 0.06. Most recent height Z' scores were +0.5 ± 0.2, and body mass index (BMI) scores were 18 ± 0.2. Late afternoon levels of 17-hydroxyprogesterone, androstenedione, and testosterone were 780 ± 238 ng/dL (23.4 ± 7 nmol/L), 42 ± 10 ng/dL (1.4 ± 0.3 nmol/L), and 11.5 ± 3 ng/dL; (0.4 ± 0.1 nmol/L), respectively. Conclusions. These observations show that low doses of dexamethasone can be used to effectively treat CAH beginning in infancy

Reactions of poly(ethylene glycol) cations with iodide and perfluorocarbon anions

AbstractMultiply charged poly(ethylene glycol) ions of the form (M+nNa)n+ derived from electrospray ionization have been subjected to reactions with negative ions in the quadrupole ion trap. Mixtures of multiply charged positive ions ranging in average mass from about 2000 to about 14,000 Da were observed to react with perfluorocarbon anions by either proton transfer or fluoride transfer. Iodide anions reacted with the same positive ions by attachment. In no case was fragmentation of the polymer ion observed. In all cases, the multiply charged positive ion charge states could be readily reduced to +1, thereby eliminating the charge state overlap observed in the normal electrospray mass spectrum. With all three reaction mechanisms, however, the +1 product ions were comprised of mixtures of products with varying numbers of sodium ions, and in the case of iodide attachment and fluoride transfer, varying numbers of halogen anions. These reactions shift the mass distributions to higher masses and broaden the distributions. The extents to which these effects occur are functions of the magnitudes of the initial charges and the width of the initial charge state distributions. Care must be taken in deriving information about the polymer molecular weight distribution from the singly charged product ions arising from these ion/ion reactions. The cluster ions containing iodide were shown to be intermediates in sodium ion transfer. Dissociation of the adduct ions can therefore lead to a +1 product ion population that is comprised predominantly of M+Na+ ions. However, a strategy based on the dissociation of the iodide cluster ions is limited by difficulties in dissociating high mass-to-charge ions in the quadrupole ion trap

The Role of Isolation in Predicting New Principals’ Burnout

Professional isolation has hampered the quality of the work experience for employees in and outside public education for decades. This study explores the role that perceived isolation plays in predicting the quality of the work experience among new principals. The analysis tests whether isolation serves as a mediator in the relationship between factors that are known to affect the quality of work life of principals (social support; role stress; and participation in a structured coaching relationship) and three dimensions of burnout. Regression analysis supports the framework that places isolation as a mediator in predicting physical and emotional burnout, but does not support this role for cognitive burnout

Adverse Events Associated with Methimazole Therapy of Graves' Disease in Children

Objective. Graves' disease is the most common cause of hyperthyroidism in the pediatric population. Antithyroid medications used in children and adults include propylthiouracil (PTU) and methimazole (MMI). At our center we have routinely used MMI for Graves' disease therapy. Our goals are to provide insights into adverse events that can be associated with MMI use. Methods. We reviewed the adverse events associated with MMI use in our last one hundred consecutive pediatric patients treated with this medication. Results. The range in the patient age was 3.5 to 18 years. The patients were treated with an average daily dose of MMI of 0.3±0.2 mg/kg/day. Adverse events attributed to the use of the medication were seen in 19 patients at 17±7 weeks of therapy. The most common side effects included pruritus and hives, which were seen in 8 patients. Three patients developed diffuse arthralgia and joint pain. Two patients developed neutropenia. Three patients developed Stevens-Johnson syndrome, requiring hospitalization in 1 child. Cholestatic jaundice was observed in 1 patient. No specific risk-factors for the development of adverse events were identified. Conclusions. MMI use in children is associated with a low but real risk of minor and major side effects

Automotive applications of high precision GNSS

This thesis aims to show that Global Navigation Satellite Systems (GNSS) positioning can play a significant role in the positioning systems of future automotive applications. This is through the adoption of state-of-the-art GNSS positioning technology and techniques, and the exploitation of the rapidly developing vehicle-to-vehicle concept. The merging together of these two developments creates greater performance than can be achieved separately. The original contribution of this thesis comes from this combination: Through the introduction of the Pseudo-VRS concept. Pseudo-VRS uses the princples of Network Real Time Kinematic (N-RTK) positioning to share GNSS information between vehicles, which enables absolute vehicle positioning. Pseudo-VRS is shown to improve the performance of high precision GNSS positioning for road vehicles, through the increased availability of GNSS correction messages and the rapid resolution of the N-RTK fixed solution. Positioning systems in the automotive sector are dominated by satellite-based solutions provided by GNSS. This has been the case since May 2001, when the United States Department of Defense switched off Selective Availability, enabling significantly improved positioning performance for civilian users. The average person most frequently encounters GNSS when using electronic personal navigation devices. The Sat Nav or GPS Navigator is ubiquitous in modern societies, where versions can be found on nomadic devices such as smartphones and dedicated personal navigation devices, or built in to the dashboards of vehicles. Such devices have been hugely successful due to their intrinsic ability to provide position information anywhere in the world with an accuracy of approximately 10 metres, which has proved ideal for general navigation applications. There are a few well known limitations of GNSS positioning, including anecdotal evidence of incorrect navigation advice for personal navigation devices, but these are minor compared to the overall positioning performance. Through steady development of GNSS positioning devices, including the integration of other low cost sensors (for instance, wheel speed or odometer sensors in vehicles), and the development of robust map matching algorithms, the performance of these devices for navigation applications is truly incredible. However, when tested for advanced automotive applications, the performance of GNSS positioning devices is found to be inadequate. In particular, in the most advanced fields of research such as autonomous vehicle technology, GNSS positioning devices are relegated to a secondary role, or often not used at all. They are replaced by terrestrial sensors that provide greater situational awareness, such as radar and lidar. This is due to the high performance demand of such applications, including high positioning accuracy (sub-decimetre), high availability and continuity of solutions (100%), and high integrity of the position information. Low-cost GNSS receivers generally do not meet such requirements. This could be considered an enormous oversight, as modern GNSS positioning technology and techniques have significantly improved satellite-based positioning performance. Other non-GNSS techniques also have their limitations that GNSS devices can minimise or eliminate. For instance, systems that rely on situational awareness require accurate digital maps of their surroundings as a reference. GNSS positioning can help to gather this data, provide an input, and act as a fail-safe in the event of digital map errors. It is apparent that in order to deliver advanced automotive applications - such as semi- or fully-autonomous vehicles - there must be an element of absolute positioning capability. Positioning systems will work alongside situational awareness systems to enable the autonomous vehicles to navigate through the real world. A strong candidate for the positioning system is GNSS positioning. This thesis builds on work already started by researchers at the University of Nottingham, to show that N-RTK positioning is one such technique. N-RTK can provide sub-decimetre accuracy absolute positioning solutions, with high availability, continuity, and integrity. A key component of N-RTK is the availability of real-time GNSS correction data. This is typically delivered to the GNSS receiver via mobile internet (for a roving receiver). This can be a significant limitation, as it relies on the performance of the mobile communications network, which can suffer from performance degradation during dynamic operation. Mobile communications systems are expected to improve significantly over the next few years, as consumers demand faster download speeds and wider availability. Mobile communications coverage already covers a high percentage of the population, but this does not translate into a high percentage of a country's geography. Pockets of poor coverage, often referred to as notspots, are widespread. Many of these notspots include the transportation infrastructure. The vehicle-to-vehicle concept has made significant forward steps in the last few years. Traditionally promoted as a key component of future automotive safety applications, it is now driven primarily by increased demand for in-vehicle infotainment. The concept, which shares similarities with the Internet of Things and Mobile Ad-hoc Networks, relies on communication between road vehicles and other road agents (such as pedestrians and road infrastructure). N-RTK positioning can take advantage of this communication link to minimise its own communications-related limitations. Sharing GNSS information between local GNSS receivers enables better performance of GNSS positioning, based on the principles of differential GNSS and N-RTK positioning techniques. This advanced concept is introduced and tested in this thesis. The Pseudo VRS concept follows the protocols and format of sharing GNSS data used in N-RTK positioning. The technique utilises the latest GNSS receiver design, including multiple frequency measurements and high quality antennas

Influence of the visual field on manual roll and lateral stabilization

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1993.Includes bibliographical references (leaves 191-192).by Scott Bradley Stephenson.M.S

CHANGES IN RUNNING GAIT PARAMETERS DURING A 161 KM TRAIL RACE

The current study examined changes in running speed and technique during a 161 km trail race and their relationship to performance. Sixteen participants were video recorded during continuous running for each of the five 32 km loops of the race. Participant’s stride length (SL), stride rate (SR), and speed were calculated. Lap and finish times were also collated from the race results. All variables changed significantly during the race (i.e. Speed?, Lap time?, SL? and SR?). Increased consistency in stride rate and length across the five laps, as well as speed, correlated positively with performance. Increased stride length in laps one, two and four correlated positively with performance. Results indicated that fatigue during the race decreased both speed and SL. Better performers ran faster with a longer SL and were able to maintain their initial speed for longer

Oligarchy contested and interconnected: The New South Wales Labor Party and the trade unions from 1910 to 1939

The period from 1910 to 1939 was one of the most turbulent chapters in New South Wales labour history. It was defined by intense ideological conflict, winner-take-all factional warfare, widespread accusations of corruption and multiple Labor Party splits. Intertwined within these issues were questions of democracy and oligarchy within the labour movement. To what extent should members control labour institutions? Democracy within unions and parties means control by the ordinary members and, where necessary, their accountable representatives. Oligarchy sits at the opposite end of the spectrum from democracy and entails organisational domination by a small group of leaders. This thesis examines the tensions and struggles between democracy and oligarchy within three key labour organisations. Events inside one major organisation affected what happened inside the others and my study is therefore relational and comparative, examining the Australian Workers Union (AWU), the Miners Federation and the NSW Labor Party. Both the AWU and NSW Labor Party were oligarchies and became more oligarchical over time. Conversely, the Miners Federation was highly democratic, although it too became less democratic over time. The NSW Labor Party was an interconnected oligarchy, both influencing and influenced by its affiliated trade unions. These influences were complicated and sometimes counterintuitive. At times the effects were straightforward, with organisations and leaders transposing their own methods into another organisation, but in other instances the participation of oligarchical unions and union leaders enhanced democracy within the Labor Party and vice versa. Oligarchy predominated in the AWU and NSW Labor Party but it was always contested. Countervailing tendencies against oligarchy were continuously operating in some form, even when the organisations were at their least democratic. My analytical framework comes from the sociological literature on trade union and political party democracy and I compare each organisation’s community, rules, local autonomy, rank-and-file decision-making, internal opposition, free communication and equality between officials and members. The key factor that separated the democratic Miners Federation from the oligarchical AWU and Labor Party was that the miners worked and lived within united, stable occupational communities in which the majority of union members and officials believed in democracy and worked towards its realisation