In healthy dogs, heart rate fluctuates during the day. Heart rate variability (HRV) reflects the autonomic nervous system´s regulation of the cardiovascular unit. Heart rate variability shows the balance between the sympathetic and parasympathetic nervous system, also called sympathovagal balance. Heart rate variability can be measured by time domain - and frequency domain analysis. In a time domain analysis you study the beat-to-beat-interval (RR-interval) in an electrocardiogram (ECG), while a frequency domain analysis can be used to determine the size of the variability.

Minimizing power consumption is a critical part of many embedded design projects. Thechallenge is to limit the power consumption of the system and at the same time providesatisfactory service to the user. With regards to microprocessors, the main way of limiting powerconsumption during program execution is to adjust the frequency and the voltage at which theprocessor operates.To enable the implementation of real-time scheduling with support for dynamic voltage andfrequency scaling, an exhaustive study of the Freescale i.MX31 embedded microprocessor isperformed. Specifically, the power consumption relationship to all relevant frequency andvoltage settings is investigated. In addition, to enable frequency and voltage scaling in a real-timeenvironment, a complete timing analysis of proposed voltage and frequency scaling methods isperformed and their suitability for use in real-time systems is evaluated.To integrate voltage and frequency scaling capability into OSE RTOS, a software module hasbeen developed for this operating system.

Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.

A power system will inevitably be subjected to transient overvoltages, most often produced by switching operations and lightning strikes. These transient overvoltages may harm sensitive equipment without sufficient protection, but it is not an easy task to predict what transients may occur or how they affect the system. A fault occurred in a low voltage system at Forsmark 2012 and overvoltages from lightning were concluded as the probable cause. The three aims with this thesis are to develop and test a model of the power system at Forsmark 3, analyse the transient behaviour of the system when subjected to lightning surges and identify critical parameters, and lastly to provide a tool for investigating the protection of the system. The modelling and simulations were performed in the freely available simulation program LT Spice.

LEXION is the name of the largest series of combines made by the CLAAS factory in Germany. LEXION was introduced on the Swedish market 1996 and was for sale in Sweden from 1997. LMB have sold over 400 LEXION-combines in Sweden. In cooperation with the Swedish general agency we decided to make a market research on the Swedish LEXION-market. The questionnaire was supposed to give answers about capacity and technical equipment. Before I made the questionnaire I studied manuals and combines. I got 81 answers of about 325 questionnaires. That makes 25 % reply frequency.

The running of gas turbines with low emissions causes high pressure pulsations to arise in the combustion chamber. These pulsations are high amplitude sound vibrations. At some frequencies these are harmful to the gas turbine. Hence these pulsations are monitored to avoid operating conditions where pulsations are specifically harmful. It is necessary to expose the system of known pulsations to verify the functionality of the monitoring process.

This Master?s Thesis deals with a special problem that may be of importance when planning a frequency hopping mobile communication network. In normal cases the Frequency Assignment Problem is solved, in order to plan the use of frequencies in a network. The special case discussed in this thesis occurs when the network operator requires that the frequencies must be arranged into groups. In this case the Frequency Assignment Problem must be solved with respect to the groups, i.e.

The supply of uninterruptible power can be applied to many areas wherecontinuous operation is highly prioritized.The application of uninterruptible power for motor operation is facilitatedusing a frequency converter. Direct current operated frequency converters canbe applied directly to the power reserve which removes the need for additionalpower-converting.Batteries have long constituted the power reserve but advancements inthe development of ultracapacitors have created a viable substitution. Ultra-capacitors have high energy storing capabilities and can be applied to highpower applications.Maxwell is a leading manufacturing company of ultracapacitors and pro-vide different modules with built-in solutions for voltage balancing. Unevenvoltages between series-connected capacitors is a phenomenon caused by vary-ing capacitance. A configuration containing Maxwell?s 56V module is createdand constitutes the power reserve in the simulations.The discharge simulation shows a significant current that could damagethe system.

A pilot study conducted on four patients, which we received from the Sahlgrenska University Hospital, who were all potential candidates for a cochlear implant. We fitted our test subjects with a pair of frequency compressing hearing aids called Phonak Naida V SP during the study and let them evaluate them for about seven weeks. Measurements made with monosyllabic words throughout the study showed significant differences in speech perception (p?0.05) compared to their regular hearing aids in 3 out of 4 cases. De-activation of the frequency transposed function showed significant decreases in 3 out of 4 cases compared to when it was activated.All test subjects were satisfied with the new hearing aids and chose to keep using them at the end of the study..

To be able to measure high-surge voltages and transients with short rise times youneed measuring instruments with a high sampling frequency and large Bandwidth.These surges and transients occur primarily at lightning but can also occur at forexample at connecting errors at an electrical switch-gear. This report describes thework with finding two solutions for measuring and log data from these surges andtransients. One temporary solution where a measurement program has beendeveloped. A second solution where different company solutions have been analyzedto decide which fits best. For these measurement solutions two solutions for bringingdown the voltage has been used.

To be able to measure high-surge voltages and transients with short rise times youneed measuring instruments with a high sampling frequency and large Bandwidth.These surges and transients occur primarily at lightning but can also occur at forexample at connecting errors at an electrical switch-gear. This report describes thework with finding two solutions for measuring and log data from these surges andtransients. One temporary solution where a measurement program has beendeveloped. A second solution where different company solutions have been analyzedto decide which fits best. For these measurement solutions two solutions for bringingdown the voltage has been used.

This thesis deals with the field of warehouse management, focusing on frequency control of stock. The purpose of the thesis is to reduce the warehouse staff mileage by placing an article based on its number of picks, i.e. how frequently it gets picked. In order to achieve relevant results the following four questions have been answered in the thesis: How should the articles be placed with regard to the picking frequency?Which factors, if any, needs to be addressed beyond the picking frequency when articles are placed based on frequency?Can the present picking system be improved?Is frequency placement with regard to the picking frequency profitable to implement for the company?The thesis is based on literature studies and on the data that has been collected from the company?s business system.

The earmould acoustics affect the amplification that the hearing aid is programmed to give to its user. It is therefore important that the choices made for the earmould are correctly done. One choice is regarding the shape of the soundbore that affects the frequency response of the hearing aid above a certain cut-off frequency. The purpose of this project was to measure the frequency response when altering the shape of the soundbore in the earmould. Additionally, the aim was to examine how the frequency response is affected when the shape of the soundbore is not set or is not possible to set in the software when programming the hearing aid.

This thesis aims to analyse a time series containing the annual accumulation rate of minerogenic matter in the lake Kassjo?n. First there is a theoretical survey of some frequently used tools for the analysis of time series in the time domain and in the frequency domain. This survey is followed by a simulation study that illustrates how the theoretical tools work in practice. After this, the time series "toolbox" is used to analyse the time series from Kassjo?n (5701 data points).

To be able to measure high-surge voltages and transients with short rise times youneed measuring instruments with a high sampling frequency and large Bandwidth.These surges and transients occur primarily at lightning but can also occur at forexample at connecting errors at an electrical switch-gear. This report describes thework with finding two solutions for measuring and log data from these surges andtransients. One temporary solution where a measurement program has beendeveloped. A second solution where different company solutions have been analyzedto decide which fits best. For these measurement solutions two solutions for bringingdown the voltage has been used.