No description available.

Any future linear collider requires a beam stabilisation system at the interaction point to the to maintain luminosities. This thesis details the development of prototypes of three such systems based at the Accelerator Test Facility 2 (ATF2) at KEK, Japan. The upstream feedback system utilises two stripline beam position monitors (BPMs) and two stripline kickers located in the ATF2 extraction line to stabilise the position and angle of the beam; the correction is then measured downstream at the ATF2 beam waist by a cavity BPM. The feedforward system uses the two upstream stripline BPMs to measure the position of the beam and calculate a correction signal which is then implemented locally by a stripline kicker located near the beam waist; the correction is then measured at the beam waist by a cavity BPM. The IP feedback system uses the position measured at the ATF2 beam waist by a cavity BPM and implements a correction based on this position using the local stripline kicker; the correction is then measured at the beam waist by a cavity BPM. Tests of the upstream feedback system have demonstrated stabilisation of the ATF2 beam waist at approximately the 300 nm level; tests of the feedforward and IP feedback systems have demonstrated stabilisation of the ATF2 beam waist at approximately the 100 nm level. Additional work undertaken to improve the processing electronics of the stripline BPMs is detailed. The cavity BPMs and their electronics are characterised and offline analysis techniques to improve the BPM resolutions set out. Results demonstrating resolutions of approximately 350 nm for the stripline BPMs and 80 nm for the cavity BPMs are presented.

No description available.

A modelling methodology, consisting of tools and techniques, has been developed to achieve quality improvement in any area of a manufacturing organisation. A 3 step approach was piloted within the Test Department at ICL Kidsgrove which tests printed circuit boards manufactured at the factory. The first step was to produce a full process model and to use this to highlight non-conformances. The next step was to develop a cost of quality model. The information from this model is used to take cost prioritised and cost justified corrective actions. The final step is to prepare a procedure which defines to the customers how to use the cost of quality information effectively. This 3 step pilot methodology was then applied to indirect functions such as Finance and Maintenance through an implementation team. The process modelling step was also developed in other quality applications such as auditing and procedure preparation. The final methodology is currently being considered for adoption as a problem solving approach throughout ICL. The process modelling step is being incorporated into auditor training. The modelling methodology, developed through this research, provides a structured, disciplined approach to quality improvement.

Ling, Chi Yeung = 作高能量密度物理研究的一種新型強離子束加速器的模擬 / 凌子陽. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (p. 111-114). / Abstracts in English and Chinese. / Ling, Chi Yeung = Zuo gao neng liang mi du wu li yan jiu de yi zhong xin xing qiang li zi shu jia su qi de mo ni / Ling Ziyang. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Background --- p.7 / Chapter 2.1 --- High Energy Density Physics and Warm Dense Matter --- p.7 / Chapter 2.1.1 --- Definition of HEDP and WDM --- p.7 / Chapter 2.1.2 --- The physics of WDM --- p.9 / Chapter 2.1.3 --- Advantages of the ion beam approach --- p.10 / Chapter 2.2 --- Intense low energy ion beam machines requirements for NDCX-II --- p.12 / Chapter 2.3 --- Neutralized Drift Compression Experiment (NDCX) --- p.14 / Chapter 2.3.1 --- Neutralized Transport Experiment (NTX) --- p.15 / Chapter 2.3.2 --- The first NDCX --- p.18 / Chapter 2.4 --- Accelerator architectures proposed for NDCX-II --- p.20 / Chapter 2.4.1 --- Radio Frequency Linear Accelerator (RF Linac) --- p.20 / Chapter 2.4.2 --- Electrostatic accelerator --- p.23 / Chapter 2.4.3 --- Drift Tube Linac (DTL) --- p.23 / Chapter 2.4.4 --- Linear Induction Accelerator (induction linac) --- p.24 / Chapter 2.5 --- Pulse Line Ion Accelerator --- p.25 / Chapter 2.6 --- Review on tests of Pulse Line Ion Accelerator --- p.30 / Chapter 2.7 --- Simulation codes --- p.32 / Chapter 2.7.1 --- 3-D Electromagnetic code MAFIA --- p.33 / Chapter 2.7.2 --- Particle-in-cell code WARP --- p.35 / Chapter 2.8 --- Envelope equation of ion beam and beam diagnostics --- p.37 / Chapter 3 --- Investigations on insulator breakdown in the PLIA --- p.40 / Chapter 3.1 --- Modeling in MAFIA --- p.40 / Chapter 3.2 --- Scaling Law --- p.42 / Chapter 3.3 --- Investigation of different frequency modes near insulator surface --- p.46 / Chapter 3.4 --- Standing wave effect in PLIA --- p.50 / Chapter 3.5 --- Conclusion --- p.52 / Chapter 4 --- PLIA based design for the second Neutralized Drift Compression Experiment --- p.55 / Chapter 4.1 --- The injector --- p.56 / Chapter 4.2 --- Pulse Line Ion Accelerator sections --- p.60 / Chapter 4.2.1 --- Basic design strategy --- p.60 / Chapter 4.2.2 --- Simulation results of PLIA sections --- p.69 / Chapter 4.3 --- Neutralized Drift Compression Section --- p.77 / Chapter 4.3.1 --- Drift length --- p.78 / Chapter 4.3.2 --- First focusing solenoid --- p.80 / Chapter 4.3.3 --- Plasma-filled region --- p.84 / Chapter 4.3.4 --- Final focusing solenoid and the best focal point --- p.88 / Chapter 4.3.5 --- Sensitivity to drift length and focusing strength --- p.91 / Chapter 4.4 --- Conclusion --- p.92 / Chapter 5 --- Other Pulse Power Options --- p.94 / Chapter 5.1 --- The injector and the beamline --- p.95 / Chapter 5.2 --- 3-meter electrostatic column --- p.97 / Chapter 5.3 --- Induction linac --- p.100 / Chapter 5.4 --- Hybrid of induction linac and Pulse Line Ion Accelerator --- p.104 / Chapter 5.5 --- Conclusion --- p.107 / Chapter 6 --- Discussions --- p.108 / Chapter 6.0.1 --- Future development of PLIA --- p.110 / Bibliography --- p.111

Due to the difficulty of a complex commissioning technique for a multi energetic, multi-modality linear accelerator, I perform all the commissioning and acceptance testing for a TrueBeam linear accelerator with 4 megavoltage (MV) energies of which 2 are flattening filter-free (FFF) and 6 electron energies varying from 6 MeV to 20 MeV. A 2 dimensional (2D) water tank was used for scanning all the required field sizes for all the energies. The one dimensional (1D) water tank was used to collect all the output factors for all the photon fields sizes small to medium electron field sizes. For the large electron fields sizes, we had to use the 2D water tank. All the collected data was converted into a file type accepted by the planning system (Eclipse) and subsequently imported there. Treatment plans were generated using multiple forms of planning to verify the viability and quality of the beam data commissioned. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection

The measurement of productivity in health care is difficult. Studies in various specialty disciplines of medicine have identified that the variation in complexities (casemix) between departments or hospitals will vary and therefore will affect any basic productivity statistics that are produced. Radiation oncology is a discipline of medicine where no such studies into radiotherapy casemix variations and the effect that these may have on productivity measures have been performed, despite the high capital expenditure involved in the delivery of radiotherapy. Radiation oncology productivity on linear accelerators is currently measured by the number of patients treated or number of treatment fields treated per unit time (usually per hour). These statistics have been collected for many years and productivity assessments were made on the variations in these statistics that exist between departments. However, these statistics do not consider the variations in casemix that occur between departments. These complexity differences may be quite marked and therefore may strongly influence the ability of a department to achieve a high patient or treatment field throughput. This may be seen as 'reduced productivity' with no consideration of the complexity of the caseload seen in the department. In addition, future technological changes that improve patient outcome may be introduced. These changes may make treatment more complex. Using older measures of productivity such as fields per hour or patients per hour will not consider these technological changes and the subsequent changes in complexity and hence departments may be seen as less productive in the future using current methods of analysis unless a more valid measure of productivity that considers complexity variations is introduced. There have only been 3 previous attempts at developing measures of linear accelerator productivity. Each of these models have been developed empirically and have not been clinically validated. No previous attempts have been made in determining a scientifically-derived complexity model that considers the variations in treatment technique. This thesis describes research performed between 1995 and 2001. This research study???s primary aims were to study the factors that affect radiotherapy treatment time and treatment complexity and to develop a model of linear accelerator productivity that does consider complexity variations in radiotherapy treatment delivery. This model is called the Basic Treatment Equivalent (B.T.E.). This series of trials examines the old models of linear accelerator productivity, describes the derivation and validation of the BTE model both in Australasia and the United Kingdom, identifies the factors that contribute to treatment time and treatment complexity, describes the development of a pilot model of productivity of gynaecological brachytherapy and outpatient chemotherapy using similar BTE methodology, discusses the potential uses of the BTE model, recent independent reviews of BTE by other groups, and the advantages and disadvantages of using such a model. This research has shown that it is possible to identify the various factors that contribute to treatment time and treatment complexity and to derive a model of linear accelerator productivity that considers the variations in complexity. The BTE model has been clinically validated in Australia, New Zealand and a couple of departments in the United Kingdom and Canada and has been adopted as a new measure by various groups. It requires regular updating to maintain currency particularly as there are frequent improvements in radiation treatment technology. Future studies should identify the differences these technological enhancements make to productivity. The BTE derived from outpatient chemotherapy delivery and gynaecological brachytherapy delivery shows promise although these models require further research with the assistance of other departments.

<p>In this master thesis, the possibilities of customizing a low-cost microprocessor with the purpose of replacing an existing microprocessor solution are investigated. A brief survey of suitable processors is carried out wherein a replacement is chosen. The replacement processor is then analyzed and extended with accelerators in order to match set requirements.</p><p>The result is a port of the processor Lattice Mico32 for the FPGA curcuit Xilinx Virtex-5 which replaces an earlier solution using Xilinx MicroBlaze. To reach the set requirements, accelerators for floating point arithmetics and FIR filtering have been developed. The toolchain for the processor has been modified to support the addition of accelerated floating point arithmetics.</p><p>A final evaluation of the presented solution shows that it fulfills the set requirements and constitutes a functional replacement for the previous solution.</p>

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 124-132). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 124-132). Also available on the Internet.