The International Organization for Standardization (ISO) proposes vibration standards for the evaluation for machine damage due to vibration in rotational machines, where some vibration parameters are given to measure the vibrationgrade. This work evaluates the relevance of the vibration standards in hydro plants that are proposed by the ISO, and also investigates if there are methods used in other countries could have greater importance. Through statistical analysis of collected data we got a better understanding of relation among different vibration parameters, and also the importance of correct choice of the parameters for the evaluation of vibration. We have found that the vibration standards available today in hydro plants are not reliable for the judgment of vibration?s grade.

On board ships different type of maintenance activities take place. Some of those require working with vibrating handheld tools. Traditionally there is a high awareness of the risks with different type of duties such as protecting the skin from oil or other chemicals, the eyes from splashes and hearing from high noise levels. The experience we have from our time as on-board cadets are that there is less information about vibration hazards available compared to the information concerning other hazards on board.There are threshold values that workers, by law, are not allowed to exceed when working with handheld vibrating tools. The purpose of this study is to investigate how common the use of this type of equipment that can cause damage by vibrations, to the hands and arm amongst the deck crew, and if the crew informed about the risks involved.

Syfte: Målsättningen med studien är att hos friska kvinnor utvärdera om intensiv tuggning leder till en proprioceptiv allodyni i massetermuskulaturen. Följande hypoteser testades i studien: 30 minuters intensivt tuggande leder till (1) ökad trötthet och smärta, (2) sänkt smärttröskel, (3) ökad vibrotaktil känslighet (4) samt träningsvärk i massetermuskulaturen bilateralt. Material och Metod: 16 friska kvinnor (medelålder 25.8 ± 5.0 år) deltog i studien som bestod av två 60-minuters sessioner med 24-timmars uppföljning. Vid ena sessionen tuggade försökspersonerna på ett grekiskt tuggummi (Masticha Chios) i 5-minuters intervaller under 30 minuter, och vilade vid den andra sessionen. En vibrameter användes för att mäta vibrationströskel, upplevd vibrationsintensitet och upplevd vibrationsobehag.

ObjectiveThe objective of this study was to investigate the clinical application to use ASSR in anesthetized childrenDesignOne main ambition of the investigation was to compare hearing threshold using ABR with estimated hearing threshold using ASSR. Another aim was to examine if the duration of an ASSR measurement could be reduced by only using the frequencies 1, 2 and 4 kHz and exclude the frequency 0.5 kHz. This is a retrospective study using electrophysiological measurement from a database.ResultResults showed a high correlation between hearing threshold using ABR and estimated thresholds using ASSR, with the frequency 0.5 kHz showing a slightly lower correlation. Result also showed that the test duration was increased when using all test frequencies in ASSR-measurement compared to when 0.5kHz was excluded. ConclusionThe study showed a high correlation when comparing hearing threshold using ABR and ASSR.

Thermia Värme AB is one of the market leading manufactures of heat pumps. In order tomaintain this position, the company wants to improve the vibration characteristics of theirproducts. The aim of this thesis is to develop product design changes that lead to a reductionof vibrations in the heat pump Thermia Diplomat 8.The main cause for vibrations in the system is flow pulsation and mechanical forces inducedby the scroll compressor. Vibration is transmitted through the compressor piping and receivedby the heat exchangers, from where it is further transmitted to the connection points for theradiator and heat source circuits.A number of design changes in order to improve the vibration characteristics have beenevaluated through calculations and practical experiments. The changes have included thecompressor and heat exchanger mountings, the compressor suction and discharge line pipingand also pulsation dampening.The results of the experiments show that the vibration levels in the connections for the heatingand brine circuits can be decreased strikingly through changes in suction and discharge linepiping.

The aim of the study has been to investigate physiotherapists? view on a new method of treatment in physiotherapy. In this case we have studied Whole Body Vibration training as an example of a new method of treatment. Semistructured interviews were performed with five physiotherapists. The study was carried out as a qualitative content analysis study.

Information about vibration injuries as a preventive measure is beneficial to society as well as the individual. As early as after a few years work with machines that vibrate can cause young sensitive persons to develop vibration injuries.An evaluation has been done on a web page with focus on information about work related vibration injuries. As a part of the evaluation a user observation and interview study was performed with workers who worked in different occupations. The workers all used machine that vibrate as part of the work. A total of eleven workers participated in the study.

The purpose of the set of regulations as regards to accounting and auditing within the Union, is primarily to ensure a high quality of the large public companies financial reporting and hence protect the capital market investors. As the set of regulations also applies to the small companies, these are burdened by administrative costs that are disproportionate. To increase the competitiveness of the European companies, the European council has stated that it is essential to reduce the companies? administrative costs. The main principle is that all companies are under an obligation to statutory audit, however Member States may make audit exemptions for small companies.

In cooperation with Hälsoteamet Halmstad a pilot study was made to see if whole body vibration exercise has any effect on muscle strength, movement and experience of pain in people with knee osteoarthritis. Today whole body vibration exercise is a revolutionary exercise method that needs more studies to show the positive and negative effects. Osteoarthritis is a degenerative disease where more cartilage is destroyed than replaced. The most common symptoms are pain, stiffness, restricted movement, muscularly atrophy, tenderness and instability. The cartilage needs pressure to rebuild, it is therefore important that the patient exercise.

A number of studies in human medicine has documented positive effects of whole body vibration treatment in humans. The Vitafloor system, witch is based on treatment of horses with vibration, has the purpose to be used in training of healthy horses and as rehabilitation for horses with injuries in their musculosceletal system. The purpose of this study was to analyse what happens with a clinically healthy horse during treatment with Vitafloor. The methods used is mainly thermography before and after treatment, but also blood samples, measurement of rectal temperature, heart rate, clinical examination and observation of psychic reactions has been done. Statistic significant changes in skin temperature in hoofs and fetlocks of front legs has been observed after treatment with Vitafloor. Analyzing of the blood samples showed a tendency for decrease in Kalium, and two of the horses had changes in CK. No negative effect has been observed with the treatment of horses with Vitafloor, and the horses seems to like the treatment. .

Att skatta sannolikheter för extrema händelser är svårt eftersom de sällan inträffaroch underlaget att bygga skattningar utifrån är begränsat. Ofta används skattningsmetodergrundade på asymptotiska resultat från extremvärdesteorin som inte självklart äruppfyllda när man utgår från en verklig datamängd. I den här uppsatsen har en sådan metod, som kallas peak over threshold-metoden, jämförts med en modifierad metodsom inte bygger på sådan asymptotik; fastypsmetoden. I peak over threshold-metoden skattas den betingade sannolikheten att befinna sig långt ut i svansen av en fördelning med hjälp av en generaliserad paretofördelning. I fastypsmetoden skattas istället den betingade sannolikheten att befinna sig långt ut i svansen med en fastypsfördelning.

Studien hade ett primärt och ett sekundärt syfte. Primära syftet var att genomföra en empirisk studie gällande vibration/accelerationsträning och undersöka om vibration/accelerationsträning påverkar styrka och balans. Sekundära syftet var att utföra en litteraturstudie och utvärdera positiva, negativa och uteblivna effekter av vibration/accelerationsträning.I studien deltog från start av studien 16 stycken kvinnor med en medelålder på 45 år, varav tre stycken kvinnor fullföljde studien. Testpersonerna tränade tre gånger i veckan under åtta veckor. Träningsprogrammet som utfördes innehöll 14 stycken övningar och tog cirka 20 minuter att genomföra.

Concrete floors have traditionally had no problems with annoying vibrations. However with the demand for larger spans the floors need to be made more slender with a higher degree of utilization and lower mass. Therefore new floors may have problems with vibration serviceability. This thesis studies the vibration characteristics of hollow core slabs. The analysis was made in the finite element program Ansys. The hollow core slab was subjected to a varying force simulating one person walking across the slab.

In this work, a method was developed and evaluated for calculating the life of welds under the influence of fatigue loads from a vibration environment. Typically, a shaker table is used for testing a component against vibration loads. The shaker table creates a vibration environment that is defined in the frequency domain by a power spectrum.Similarly, a virtual vibration table can be used to calculate the same type of load environment, which can then be used to calculate the expected lifetime. The benefit of this method is that it can be used in design, as well as in simulation of tests before physical verification tests are carried out.Today there are methods for calculating fatigue life of non-welded base material, but since many components contain welded joints, there is a need to apply this method to those types as well. To achieve this, the thesis combines two different areas, which together provide a method for fatigue assessment of welds using a virtual shaker table.The methodology is carried out by modeling the component, and its welded joints, in a finite element program.

Active Vibration Control of a Laser PatternGenerator in Microlithography.