The subject of this diploma thesis is design of motion axes of horizontal milling and boring machines. The first part contains literary research of linear systems of feeding and equipment. The second part contains calculations and the design of the motion machine axis. The 3D model of the motion axis designed in SolidWorks 2010 software and part of drawings are also included in this thesis.

The diploma thesis is focused on the construction design of elevator for pallets with car seats weighing 200 kg. This device is proposed for vertical transport of the load between two working positions which are separated by 6m. Part of the pallet hoist is a roller conveyor attached on a lifting frame. The roller conveyor allows loading and unloading pallets from the fixed roller conveyors in the lower and upper station. There are the functional calculations of important parts, strength control of traction belt and shaft of driving pulley drum. By FEM (Finite Element Method) is detected stress distribution of the lifting frame. Parts of the annex are the manufacturing drawings of the lifting frame, shaft of driving drum, the driving station and drawing of the whole assembly vertical conveyor. Furthermore, the timing diagram function for one cycle, risk analysis and FMEA.

Growing memory capacities and the increasing number of cores on modern hardware enforces the design of new in-memory indexing structures that reduce the number of memory transfers and minimizes the need for locking to allow massive parallel access. However, most applications depend on hard durability constraints requiring a persistent medium like SSDs, which shorten the latency and throughput gap between main memory and hard disks. In this paper, we present our winning solution of the SIGMOD Programming Contest 2011. It consists of an in-memory indexing structure that provides a balanced read/write performance as well as non-blocking reads and single-lock writes. Complementary to this index, we describe an SSD-optimized logging approach to fit hard durability requirements at a high throughput rate.

В результате условий эксплуатации коммунальной техники снижается надёжность гидравлических систем, повышаются затраты на техническое обслуживание и резко снижается производительность машины в целом. Для выявления недостатков гидропривода щеточного узла коммунальной машины и разработки мероприятий по их устранению, необходима имитационная модель с возможностью изменения кинематических и динамических параметров. В ходе данной работы были рассчитаны параметры гидропривода с помощью программы Mathcad, создана твердотельная имитационная модель щеточного узла МК2000 с подключенным гидроприводом используя пакета программ MATLAB Simulink Multibody/Fluids. Наличие имитационной модели позволяет в дальнейшем анализировать изменения в динамике механизма на этапе проектирования; верно подобрать ответственные узлы; уменьшить затраты времени на сложные расчеты; повысить качество построения механизма с исключением человеческих ошибок. / The operating conditions of municipal equipment reduce the reliability of hydraulic systems, increase maintenance costs, and drastically reduce the overall performance of the machine. A simulation model with the possibility of changing kinematic and dynamic parameters is needed to identify the disadvantages of the hydraulic drive of the municipal machine brush unit and to develop measures for their elimination. In the course of this work parameters of hydraulic drive were calculated using Mathcad program, a solid-state simulation model of the sweep gear MK2000 with connected hydraulic drive was created using MATLAB software package Simulink Multibody/Fluids. The simulation model allows further analysis of changes in mechanism dynamics at the design stage; to correctly select responsible units; to reduce time spent on complex calculations; to increase quality of mechanism construction with exclusion of human errors.

В данной работе изучено общее строение станов ХПТ и в частности строение приводного механизма. На основе этих данных созданы модели деталей привода в системе трехмерного моделирования КОМПАС-3D. В программе Mathcad рассчитаны данные переходных процессов пуска двигателя, а в программе для моделирования систем Simulink смоделирован двигатель. Далее в среде для имитационного моделирования многозвенных трёхмерных механических систем Simscape Multibody собрана блок-схема приводного механизма рабочей клети стана ХПТ, к ней подключён электродвигатель. В результате исследования была получена имитационная модель приводного механизма рабочей клети стана ХПТ-90, проведена симуляция и исследование её работы. Данная модель позволяет: наглядно продемонстрировать работу механизма; обнаружить ошибки в работе; определить оптимальные параметры прокатки; оптимизировать процессы; снизить стоимость испытаний механизма; снизить затраты времени при проектировании. / In this work, the general structure of cold pipe rolling mills and, in particular, the structure of the drive mechanism were studied. Based on these data, models of drive parts were created in the KOMPAS-3D three-dimensional modeling system. The motor starting transient data was calculated using Mathcad, and the motor was simulated using the systems modeling software Simulink. Next, in the simulation environment for multi-link three-dimensional mechanical systems Simscape Multibody, a block diagram of the drive mechanism of the working stand of a cold pipe rolling mill was assembled, and an electric motor was connected to it. As a result of the study, a simulation model of the drive mechanism of the working stand of the cold pipe rolling mill (ХПТ-90) was obtained, a simulation and study of its operation was carried out. This model allows you to: clearly demonstrate the operation of the mechanism; detect errors in operation; determine optimal rolling parameters; optimize processes; reduce the cost of testing the mechanism; reduce time spent on design.

Das Kolloquium Getriebetechnik findet seit 1995 im zweijährigen Turnus statt. Im aktuellen Tagungsband zum 9. Kolloquium in Chemnitz werden in 22 Fachbeiträgen aktuelle Lehr- und Forschungsschwerpunkte aus den Gebieten der Bewegungs-, Getriebe,- und Antriebstechnik, Berechnung und Simulation bis hin zu internetbasierten Wissensportalen vorgestellt. Besondere Themenschwerpunkte sind einerseits die aktuellen und zukünftigen Ausbildungsstrategien im Themengebiet der ungleichmäßig übersetzenden Getriebe an den Universitäten und Fachhochschulen. Andererseits werden die aktuellen F&E-Aktivitäten der einzelnen Professuren und Institute sowie Applikationen von Firmen präsentiert. Dabei stehen heute neben den mechatronischen Antriebssystemen auch verstärkt werkstofftechnisch bzw. bionisch geprägte Konzeptideen im Focus. Neben neuen und effizienten CAD-Lösungsstrategien zeigen die Beiträge ganzheitliche Lösungsansätze sowie den Einsatz der Mehrkörpersimulation und FEM im Umfeld der Getriebeentwicklung.

The thesis presents phase stability studies for the Compact Linear Collider (CLIC) and focuses in particular on CLIC Drive Beam longitudinal phase stabilisation. This topic constitutes one of the main feasibility challenges for CLIC construction and is an essential component of the current CLIC stabilisation campaign. The studies are divided into two large interrelated sections: the simulation studies for the CLIC Drive Beam stability, and measurements, data analysis and simulations of the CLIC Test Facility (CTF3) Drive Beam phase errors. A dedicated software tool has been developed for a step-by-step analysis of the error propagation through the CLIC Drive Beam. It uses realistic RF potential and beam loading amplitude functions for the Drive and Main Beam accelerating structures, complete models of the recombination scheme and compressor chicane as well as of further CLIC Drive Beam modules. The tool has been tested extensively and its functionality has been verified. The phase error propagation at CLIC has been analysed and the critical phase error frequencies have been identified. The impact of planned error filtering and stabilisation systems for the Drive Beam bunch charge and longitudinal phase has been simulated and the optimal specifications for these systems, such as bandwidth and latency time, have been calculated and discussed. It has been found that a realistic feed-forward system could sufficiently reduce the longitudinal phase error of the Drive Beam, hence verifying that a satisfactory CLIC luminosity recovery system is possible to develop. Alternative designs of the Drive Beam accelerator, the recombination scheme and the phase signal distribution system have also been analysed. Measurements of the CTF3 Drive Beam phase have been performed. The source of the phase and energy errors at CTF3 has been determined. The performance of the phase feed-forward system prototype for CTF3 has been simulated. The prototype's specifications have been defined so that it will provide a sufficient test of the feed-forward correction principle. The prototype based on the defined specifications is currently in development and is to be installed at CTF3 in the second half of 2013.

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: With the current worldwide energy problems electric vehicles are set to replace conventional combustion engine vehicles. Electric vehicles with gearless in-wheel mounted brushless permanent magnet motors provide a more flexible and efficient means of vehicle propulsion but the electric motors, particularly the non-overlap stator winding type have not been fully researched. This study focuses on the selection and design of suitable in-wheel hub drive machine. Several machine topologies are evaluated and the single-sided axial flux machine is chosen. The average vehicle requirements are determined and design optimisations are carried with the aid of finite element analysis and an optimisation algorithm. A comparison of torque quality between single-layer and double-layer machines is carried out and it is found that double-layer machines have the least torque ripple and single-layer machines with un-equal teeth the best torque per ripple characteristics. A 16 kW, 30-pole 27-slot prototype machine optimised for power density is built, and it is found fitting for the application meeting the design requirements. The prototype machine is extensively tested and good agreement is found between finite element and measured results. The well known axial flux attraction forces are encountered in the prototype machine and they are overcome by suitable bearing selection and mechanical design. It is found that theoretical and measured cogging torques are inconsistent, the reason for this is that practical machines are not absolutely ideal due to material and manufacturing tolerances. Excessive rotor losses are found in the prototype machine and appropriate methods for their reduction are presented. This work does not aim to find the best in-wheel hub drive solution, but instead looks to uncover some of the technical available solutions. / AFRIKAANSE OPSOMMING: Met die huidige wêreldwye energie probleme, is elektriese voertuie bestem om konvensionele binnebrandenjin voertuie te vervang. Elektriese voertuie met ratlose binnewiel-geleë borsellose permanente magneet motors, voorsien „n meer aanpasbare en effektiewe metode van voertuig aandrywing, maar die elektriese motors, veral die oorvleulende stator winding tipe is nog nie ten volle nagevors nie. Hierdie studie fokus op die keuse en ontwerp van „n binnewiel aandryf masjien. Verskeie masjien uitlegte word geëvalueer en „n enkelkant aksiaalvloed masjien is gekies. Die gemiddelde voertuig behoeftes word bepaal en ontwerp optimalisering word uitgevoer met behulp van eindige element analise en „n optimaliserings algoritme. Enkellaag en dubbellaag masjiene se draaimoment kwaliteit word vergelyk. Die bevinding is dat dubbellaag masjiene die laagste draaimoment rimpel toon terwyl die enkellaag masjiene, met oneweredige tande, die beste draaimoment per rimpel karakteristieke toon. „n 16 kW, 30 pool, 27 gleuf prototipe masjien, wat vir drywingsdigtheid ge-optimaliseer is, is gebou en is geskik vir die toepassing en die vereistes. Die prototipe masjien is getoets en goeie vergelykings word getref tussen die eindige element analise en die gemete resultate. Die alom bekende aksiaal vloed aantrekkings kragte word in die prototipe masjien gesien en word oorkom deur die regte rollaer keuse en meganiese ontwerp. Nog „n bevinding is dat die teoretiese en gemete waardes vir die vertandings draaimoment nie ooreenstem nie. Die rede hiervoor is dat die praktiese masjien nie ideaal is in terme van materiaal en vervaardigings toleransies nie. Groot rotor verliese in die prototipe masjien is gevind en goeie metodes vir die minimering daarvan word voorgestel. Hierdie werk is nie „n soektog na die beste binnewiel aandrywings oplossing nie, maar mik eerder om sommige van die tegniese beskikbare oplossings te onthul.

The first aim of this study was to develop a research based, integrated, secondary prevention programme, called the Weight Over-concern and Well-being (WOW) programme, for the reduction of Subclinical Eating Disorder (SED) symptoms, associated traits and negative mood states, and the promotion of psychological well-being (PWB) in female students. Consequently the second aim was to determine the effectiveness of the WOW-programme on its own, in comparison with a combined Tomatis Method of sound stimulation (Tomatis, 1990) and WOW-programme, regarding the reduction of SED-symptoms, associated traits and negative mood states; the promotion of PWB; and outcome maintenance. The last aim was to obtain a deeper understanding and "insiders' perspective" of the lived experience of SED, through an interpretative phenomenological inquiry (Smith & Osborn, 2003). The motivation for the current study is a need for research based, integrated, risk-protective, secondary prevention programmes from a social-developmental perspective for female university students (Garner, 2004; Phelps, Sapia, Nathanson & Nelson, 2000; Polivy & Herman, 2002), given their risk status (Edwards & Moldan, 2004; Senekal, Steyn, Mashego & Nel, 2001; Wassenaar, Le Grange, Winship & Lachenicht, 2000). Concurrently in-depth descriptions from an "insiders' perspective" on the lived experience of SED are non-existent and require interpretative phenomenological study (Brocki & Wearden, 2006). Consequently this thesis consists of three articles, namely: (i) Development of a secondary prevention programme for female university students with Subclinical Eating Disorder, (ii) A secondary prevention programme for female students with Subclinical Eating Disorder: a comparative evaluation; and (iii) Lived experiences of Subclinical Eating Disorder: female students' perceptions. The research context comprised Subclinical Eating Disorder, secondary prevention and Positive Psychology. The first article, Development of a secondary prevention programme for female university students with Subclinical Eating Disorder (Kirsten, Du Plessis & Du Toit, 2007a), is qualitative in nature, and narrates a process of participatory action research followed to develop the WOW-programme. This social process of knowledge construction, embedded in Social Constructivist theory (Koch, Selim & Kralik, 2002), gradually revealed best clinical practice, and in retrospect, evolved over four phases. Phase One comprised experiential learning based on personal experiences with SED as undergraduate student and interaction with "participant researchers" as scientist practitioner (Strieker, 2002), resulting in a provisional risk model of intervention. Phase Two, a formal pilot study (Du Plessis, Vermeulen & Kirsten, 2004), afforded an evaluation of ideas generated in Phase One through a three-group pre-post-test design. Outcomes of Phase Two informed Phase Three, an integration of prior learning with Positive Psychology theory and clinical practice, resulting in a risk-protective model of prevention. Theoretical assumptions previously constructed were integrated and operationalised during Phase Four, into the final 9-session WOW-programme. In conclusion the process of knowledge construction was rigorous, despite the small overall sample size (n=28), since data saturation occurred within that sample. Although the multitude of aims involved in each session of the WOW-programme could be seen as unrealistic, in some direct or indirect way, they were addressed by means of relevant interventions due to the integrative approach. Thus future refinement is essential. Finally, despite aforementioned concerns, the WOW-programme proved to be robust on its own in reducing SED-symptoms and associated traits and enhancing PWB, as described in the second article of this thesis. The second article, A secondary prevention programme for female students with Subclinical Eating Disorder: a comparative evaluation (Kirsten, Du Plessis & Du Toit, 2007b), describes the outcomes of the WOW-programme on its own, evaluated comparatively with a combined Tomatis sound stimulation and WOW-programme. In this article the research aims were to determine: (i) whether participation in the combined sound stimulation and WOW-programme (Group 1); and (ii) participation in a WOW-programme only (Group 2), would lead to statistically significant reductions in SED-symptoms, psychological traits associated with eating disorders and negative mood states, and enhancement of PWB; (iii) whether results of Groups 1 and 2 would exceed results of a non-intervention control group (Group 3) practically significantly; and (iv) whether programme outcomes for Groups 1 and 2 would be retained at four-month follow-up evaluation. A mixed method design (Creswell, 2003; Morse, 2003) was used, including a three-group pre-post-test (n=45) and multiple case study (n=30) design. Various questionnaires measuring SED-symptoms, associated traits, negative mood states and PWB were completed. Qualitative data were obtained by means of metaphor drawings, letters to and from the "SED-problem", focus group interviews, the researchers' reflective field notes and individual semi-structured feedback questionnaires (Morse, 2003). Participation in Groups 1 and 2 proved effective, since decreases in SED-symptoms, associated traits, most negative mood states, and increases in PWB differed practically significantly from the results of Group 3. Outcomes for Groups 1 and 2 were maintained at four-month follow-up evaluation. Qualitative findings provided depth, support and trustworthiness to quantitative findings in light of the small sample size, and highlighted the value of using a mixed method design in prevention programming. It was concluded that the WOW-programme on its own, was an effective secondary prevention programme, since it led to reduced SED-symptoms, associated psychological traits and enhanced PWB, with retention of gains at four-months follow-up evaluation. The combined programme involving Tomatis stimulation and WOW-intervention proved to be even more effective, thus the complimentary role of Tomatis stimulation was demonstrated. However, the cost-effectiveness and comparative brevity of the WOW-programme rendered it the programme of choice regarding individuals with SED. Findings showed that conceptually, pathogenic and salutogenic perspectives can be successfully combined into a risk-protective model of secondary prevention. Lastly, the WOW-programme may even prove useful as an enrichment programme for female students in general. The third article, Lived experiences of Subclinical Eating Disorder: female students' perceptions (Kirsten, Du Plessis & Du Toit, 2007c), provides a qualitative, in-depth perspective on the lived experience of SED of 30 white, undergraduate females, purposively sampled. In this interpretative phenomenological, multiple case study (Brocki & Wearden, 2006), Groups 1 and 2 of the aforementioned primary study in the second article were used, since they fitted the criteria of "good informants" and were able to answer the research question (Morse, 2003). Further sampling was deemed unnecessary since data saturation occurred within their written and verbal responses and no negative cases were found. Rich individual qualitative data, further clarified through focus groups, emerged from graphic colour representations of lived SED, explanatory written records and "correspondence" with and from their "SED problem" (Gilligan, 2000; Loock, Myburgh, & Poggenpoel, 2003; White & Epston, 1990). Four main categories, characterised by serious intra-, interpersonal, existential and body image concerns were subdivided into seven subcategories, namely: Personal Brokenness, Personal Shame, Perceived Personal Inadequacy and Enslavement, Existential Vacuum, Perceived Social Pressure, Perceived Social Isolation and Body-image Dysfunction. Results were indicative of underestimation of SED-severity, its comprehensive detrimental impact on participants' PWB and high risk for escalation into full-blown eating disorders. It was concluded that the lived experiences of SED depicted the severity of SED-symptoms; descriptions resonated well with most of their pre-programme mean scores; and their risk status and need for contextually and developmentally relevant secondary prevention programmes were highlighted by the findings. / Thesis (Ph.D. (Psychology))--North-West University, Potchefstroom Campus, 2008.

A new torque transfer standard using metallic TBTF resonant sensor was developed to overcome the overload capability problem which occurs with conventional metallic resistance strain gauges. Previous research work, however, has shown that the first prototype of the metallic TBTF resonant sensor was not suitable for use in a torque transfer standard due to its size and subsequent sensitivity to parasitic lateral forces. To maximize the benefits from this sensor, particularly overload capability and long-term stability, in the high accuracy torque measurement application area, there is a need to develop significantly smaller devices. The aim of this thesis is to research through FEA modelling and experimental characterisation the key performance parameters required to produce a miniaturised metallic TBTF resonant sensor that provides better performance when applied in a torque measurement system. For high accuracy any torque transducer using these sensors ought to have low sensitivity to parasitic influences such as bending moments and lateral forces, which can only be achieved with reduced size. The problems with the existing design, key design issues, possible configuration and packaging solutions of the metallic TBTF resonant sensor that could be used for achieving a higher accuracy torque transfer standard are considered. Two designs of miniaturised metallic TBTF resonant sensors, SL20 and SL12, are considered and experimentally investigated. The lateral forces are reduced by 52% for SL20 design and by 80% for SL12 design when compared to the original SL40 design. A torque transducer using the SL20 design was calibrated falling into the Torque Transfer Standard class of accuracy 1 category, uncertainty 0.8%. A torque transducer using the SL12 design was made and calibration showed a class of accuracy 0.5 category, uncertainty 0.2%. The results from this research indicate that the SL12 design is suitable for use in a torque transfer standard. The SL12 design is optimal and the smallest size possible based on the overload capability design criteria requiring the tine cross sectional area to remain constant.