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International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Low cost recording devices for telemetry and other data acquisition applications are of vital importance in light of today's shrinking budgets and project cut-backs. The desire to replace large, expensive, multi-channel recorders with smaller, less expensive recorders is becoming commonplace in government and industry. Many of these small recorders in the past have been limited to a single recording channel, and to one particular data type, due to recorder architectures. The 8 millimeter (8mm) tape cartridge recorder has been looked at in the past as a low cost recording device, however products utilizing this technology have been strictly limited in the number of channels, and data types. In response to this need, Veda has developed a new data acquisition recorder utilizing an 8mm recorder packaged in a small, flight qualified rugged enclosure with modular, and interchangeable, input channels. These microprocessor controlled inputs are capable of accepting PCM telemetry, MIL-STD-1553, voice, IRIG time, and ARINC 429/629 data. The new architecture allows for multiplexing of multiple channels onto the single channel tape medium as well as direct playback from the recorder for certain data types. This paper will discuss the recorder's architecture, design problems solved during development, and general capabilities.

The viability of any electric vehicle is critically dependent on it having an acceptable range between charges, a feature which is ultimately dictated by the capacity of the battery energy store. Considerable improvements in vehicle range are possible, however, by ensuring the most effective use of this limited energy resource through the minimisation of the losses in the electric drive-train, i.e. the combined machine and power electronic controller. A particular consideration is that, for the majority of the time, the electric drive-train will be operating at part load. The thesis investigates the operation of induction motor based electric traction drive-trains, with a view to minimising the system loss over typical driving cycles. The study is based around a 26kW induction motor and IGBT inverter drive, which is typical of the technology used to power a small urban vehicle. A potential advantage of an induction motor based drive-train is the ability to vary the level of excitation field in the motor, and therefore the balance of iron and copper loss. The control of the supply voltage magnitude necessitates the use of some form of modulation on the output of the power converter. The method of modulation employed will influence the harmonic content of the supply to the motor, the level of parasitic harmonic loss in the machine and the switching losses of the power semiconductors. A theoretical study supported by experimental work on a DSP controlled drive is presented and used to determine the most appropriate modulation strategy at a given operating point to achieve an optimal balance between the motor copper, iron and harmonic loss and inverter switching and conduction loss. It is shown that compared to the established method of constant flux and fixed inverter switching frequency control, a significant reduction in the traction system loss can be achieved. Some different modulation schemes involve varying amounts of computational overhead in a DSP, the implementation of candidate modulation and control schemes has also been investigated to ensure the defined scheme is practically realisable.

There is a vast diversity of karyotypes in nature, yet mechanisms that have facilitated such diversity are unclear. Alterations to an organism’s karyotype can have major negative fitness consequences in meiosis through non-disjunction and aneuploidy. Here, I investigated the role of biased segregation in female meiosis, i.e., meiotic drive, as a force that contributes to the evolution of karyotype form. The closely related species pair, Drosophila americana and Drosophila novamexicana, is an exemplar for understanding mechanisms of karyotype evolution. Since their recent divergence nearly half a million years ago, D. americana has evolved two different centromeric fusions: one fusion between the 2nd and 3rd chromosomes (Muller elements C and D), and the other fusion between the X and 4th chromosomes (Muller elements A and B). The 2-3 fusion is fixed in D. americana. However, the X-4 centromeric fusion remains polymorphic within the species. I uncovered biased transmissions for both fused chromosomes in D. americana such that the X-4 fused chromosome was inherited by 57% of the offspring from heterozygous females and the 2-3 chromosome was inherited by 62% of the offspring. Introgression experiments shoed the fused X-4 and the unfused X and 4th chromosomes are segregating at a 50/50 ratio in D. novamexicana. I have isolated the fused X-4 centromeric region as a possible player in the observed meiotic drive. However, the centromere is not sufficient to cause meiotic drive without a secondary factor. I also measured heterochromatin content between the fused and unfused X and 4th homologs. No obvious size differences were uncovered, but possible compositional differences were revealed. This suggests that if the centromere itself is involved in meiotic drive, either differences in the number of centromeres or compositional differences between the centromeres are influencing meiotic drive. Overall, I have identified and characterized meiotic drive as a force driving karyotype evolution in D. americana but appears to be absent in D. novamexicana, and I have begun to dissect the mechanisms of meiotic drive.

Ph.D. Thesis, 33 l. / Basic thesis: the behavior of any animal is the result of his drives to action and the opposing resistance.

Since the onset of automation, industry has relied on adjustable speed drives to accurately control the speed of motors. Recent advances have increased the number of adjustable speed drives hitting the market. The proper operation of the speed drives requires electrical supply with relatively high power quality which is not the case in most industrial facilities. Power quality problems such as harmonic, sag, swell, flicker, and unbalance can trip the speed drive with a wrong message, which is referred as a premature tripping. Although the power quality problems can be mitigated by using custom power devices, they are bulky and costly. Moreover, they themselves might adversely affect the operation of the adjustable speed drive. A comprehensive study done in this thesis presents the overlooked effect of the custom power devices on the speed drive stability. It is found that the speed drive system might trip due to its interaction with custom power devices. Obviously, it is vital to increase ASD immunity to premature tripping because of poor power quality or custom power. This thesis offers fast, efficient and robust algorithms to achieve this immunity by retrofitting the ASD control unit and integrating the power conditioning function with the adjustable speed drive. Therefore, the power quality problem is mitigated and the drive system performance is significantly enhamced. Such integration requires the modification of the control unit by considering various elements such as envelope tracking, phase-locked loop, symmetrical component extraction, and the controller. Simple but robust and fast algorithms are proposed for such elements based on a newly developed energy operator algorithm. The developed energy operator and the developed algorithms overcome the drawbacks of the existing algorithms.

The task of constructing a transmission has been provided to us by Digital Engineering, which is a company located in Hovmantorp. After meeting with Digital Engineering we started immediately with the brainstorming to find different ideas with pen and paper. After having presented a number of concepts for the company, we had finally chosen a winner. For the gearbox to be able to work in a good way the tension must never exceed the strain limit of the material. A prototype of the gearbox was produced by TKB Modell. Standard components that are available have been purchased from Sverull AB in Växjö.

This project has been assigned by SwePart Transmissions AB. It is about calculation and dimensioning, of the elements in a cycloid stage of a speed reducer. Their idea is to use the results from this project and go into production of such reducer to cover another segment of the market. The company is interested in supplying transmissions for robust systems and for various industrial purposes, where large ratios of speed reduction are needed. The company has given the necessary input data for the model. They have also provided a real cyclo-drive reducer for further analyses. To obtain the dimensions and forming the geometry of the gears, some parts of Professor Ognyan Alipiev’s Phd work have been used. Professor Alipiev is head of “Theory of Mechanisms and Machines” department in University of Ruse “Angel Kunchev”, Bulgaria. For the determination of forces on the elements, models and drawings has been used Solidworks (SW) CAD software and SW simulation environment. The resultant calculation process can be used for designing the geometry and determination of the properties regarding the cycloid reducer. / Design of a Planetary-Cyclo-Drive Speed Reducer

Since the onset of automation, industry has relied on adjustable speed drives to accurately control the speed of motors. Recent advances have increased the number of adjustable speed drives hitting the market. The proper operation of the speed drives requires electrical supply with relatively high power quality which is not the case in most industrial facilities. Power quality problems such as harmonic, sag, swell, flicker, and unbalance can trip the speed drive with a wrong message, which is referred as a premature tripping. Although the power quality problems can be mitigated by using custom power devices, they are bulky and costly. Moreover, they themselves might adversely affect the operation of the adjustable speed drive. A comprehensive study done in this thesis presents the overlooked effect of the custom power devices on the speed drive stability. It is found that the speed drive system might trip due to its interaction with custom power devices. Obviously, it is vital to increase ASD immunity to premature tripping because of poor power quality or custom power. This thesis offers fast, efficient and robust algorithms to achieve this immunity by retrofitting the ASD control unit and integrating the power conditioning function with the adjustable speed drive. Therefore, the power quality problem is mitigated and the drive system performance is significantly enhamced. Such integration requires the modification of the control unit by considering various elements such as envelope tracking, phase-locked loop, symmetrical component extraction, and the controller. Simple but robust and fast algorithms are proposed for such elements based on a newly developed energy operator algorithm. The developed energy operator and the developed algorithms overcome the drawbacks of the existing algorithms.