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1685 Uppsatser om Frequency distribution - Sida 9 av 113

Jämförelse mellan ?Auditory Brainstem Response (ABR) och ?Auditory Steady State Response? (ASSR) för att uppskatta hörtrösklar på barn i narkos. Kan testtiden minska om 500 Hz utesluts vid ASSR-mätning?

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.

Modell för analys och effektivisering av e-handel med tillhörande distribution : En fallstudie på EM-Möbler

Bakgrund och problem: Anva?ndningen av e-handel har va?xt de senaste a?ren och detta har medfo?rt sto?rre mo?jligheter fo?r kunder. E-handeln har mo?jlighet att na? ut till en sto?rre ma?lgrupp utan geografiska hinder. Detta medfo?r ett behov av fo?ra?ndring i distributionen av fysiska produkter.

Förekomst & kostnad av kapsprickor i stormaskadad skog

The aim for this study where to investigate the frequency of cutting cracks in saw timber harvested in the storm-damaged forests in regions where the storms Hilde and Ivar hit. The idea for this work came from one of the region?s biggest actors, SCA Skog and Jämtlands district. The purpose where to find out how big proportion of the saw timber that contains cutting cracks, their financial cost in lost wood value and also give advice and suggestions on how to work against the frequency of cutting cracks. For the field-study some guidelines where used to make sure that the samples were taken under the same conditions, they were: ? The field-study must be performed under harvesting of storm-felled forest, which are horizontal/inclined trunks. ? The averaged sized tree will make it possible to harvest saw timber. ? The trunks can?t be root cut. A methodology called in Swedish ?Trissmetoden? was used because it is the most frequent used methodology in earlier performed studies and the only one that can be used I field. Under the field-study data were collected from 570 saw timber logs, 30 logs from each one of the tested harvesters.

En studie om vad som behövs för att skolträdgårdar skall fungera under en längre tid : en utvärdering av Edane skolas skolträdgård

Tail-biting in pigs is an animal welfare issue and in Sweden during 2002 the producers lost tree million Swedish crowns because of tail biting. This economic loss depends on the pigs which are discarded at slaughter because of tail biting. Tail biting can be separated into two stages, "pre-injury" and "injury". The aim of this study is to investigate if tail biting depends on environment or genetic background.A lot of research on the environments effects on the behaviour of pigs but not so much on the genetic effects has been performed. The frequency of tail biting in pig farms influence among others of environment enrichment, ventilation, gender and breed of the pig.

Risken för spridning av röta vid förröjning i granskog i södra Sverige :

Root rot causes large economical losses for Swedish forestry. The spread of root rot can partly be prevented by treating the spruce stumps in thinnings. Late pre-commercial thinning (PCT) is one of the forestry measures where stump treatment is not used. Late PCT can be defined as: The act of cleaning the stand with the aim of improving accessibility and sight within the stand, and so to increase the mean stem´s volume during the first conventional thinning. The aim of this study was to examine how late PCT is performed, its spatial extent and if it aids the spreading of root rot. The study was limited to encompass late PCT before first conventional thinnings in spruce stands in southern Sweden. Samples of spruce stumps were taken from four stands where late PTC had been carried out.

Marknadsundersökning av Claas Lexion tröskor : kapacitet och kundnöjdhet

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.

MPD-vågformer för helikopterradar

A helicopter based system equipped with a millimetre-wave fire control radar is studied for improvement of the detection probability for moving ground targets. The system is a pulse doppler radar that sends out the electromagnetic wave in repetitive pulses. The frequency in which radar sends this pulse is called Pulse Repetition Frequency (PRF). The velocity of the moving targets is measured by spectral analysis of the pulses received. With this sort of system some targets will not be possible to detect.

RCC-Jordfelsskydd, mätmodul för övertonsanalys

The majority of all power cuts that affects individuals and communities are caused by earth faults on the power transmission lines at 10kV and 20kV level [1]. If these power cuts could be eliminated, less disturbances and interrupts would lead to large amounts of money savings.Swedish Neutral has developed such a protection system. When an earth fault occurs power is injected into the neutral point of the transformer. The RCC (Residual Current Compensation) protection calculates a compensation current exactly 180 degrees out of phase to the fault current. Doing this, the voltage at the fault location becomes very close to zero, without affecting the power transmission.The protection system can only compensate automatically for the fundamental frequency (50Hz), and manually for the 3rd, 5th, 7th and 9th harmonics.

Digital videoväxel

This thesis discusses the possibilities to distribute digital video in a military vehicle. Today, an analogue system is used, which has a maximum capacity of eighteen video sources and the same number of monitors. The purpose of this thesis is to increase the systems capabilities regarding secure distribution and additional functions. Both software and hardware tests are made to investigate the features of the digital video standard MPEG-2. Both the coding delay and the image quality are of great interest.

Konstruktionsforslag for kabelprovningsutrustning av serieresonanstyp

In order to decrease the disturbance from a cable testing equipment, the company Ericsson Network Technologies in Falun determined to design a new series resonant test system with a lower frequency. The new equipment is of series resonant type with a system frequency of 500 Hz. This equipment consists of an inductor, a capacitor and a voltage source. The voltage source is the same as the old one, the cable acts as the capacitor but the inductor has to be designed especially for the new equipment. In this thesis work several air coil inductor types were examined.

Analys och utveckling av en metod för distribution av data

Detta examensarbete omfattar utveckling och test av en metod för distribution av data i ett multidatabassystem. Testen av metoden har gjorts genom att den har implementerats i en fallstudie. Fallstudien berör en organisation som har behov av att integrera tre av sina databassystem. Detta för att information ska kunna utbytas mellan dessa. Integrationen av databassystemen har gjorts på ett sådant sätt att de data som distribueras från dessa skickas till en central databas, med SQL Server som databashanterare.Det verktyg som har valts att användas i examensarbetet för att lösa uppgiften är Data Transformation Services, DTS, i SQL Server..

Bedömning och kunskapssyn i matematik : Förändringar i lärares bedömningspraktik

This paper examines women's positions in the music industry. By quantitativelyinvestigate ten major companies on the swedish music market, the authors have beenable to mapp positions that are dominated by women and as well as men. The essaydiscusses several theories of both gender in organizations and gender in society inorder to analyze the quantitative results.The aim of the paper is to highlight the current segregation of careers in the musicindustry as well as to lay a foundation for further research on why it is segregated.Clear graphs shows the gender distribution between women and men in business butalso the distribution of gender in occupations / positions in similar companies. In theanalysis the authors reflects on the results using relevant gender theories. In theconclusion, the authors explain the result generated by the analysis and illustrates theprevailing segregation that exists in the music industry.This paper has concluded that a seemingly even distribution between men andwomen in business organisations can sometimes be misleading.

Bestämning av optimal fordonspark -Distribution av bitumen vid Nynäs AB

Nynas produces bitumen at two refineries in Sweden. The bitumen is shipped to seven depots along the swedish coast line, and from the depots special trucks handle the transportation to customers. Recently Nynas has transformed its supply chain and closed down a few depots. At the moment the company is considering a further reduction of the number of depots. In connection to these discussions an analyse of the companys distributionsystem and of possible changes is required.

Att genom design effektivisera räddningsinsatsen för motorcyklister i trafikolycka

What if the emergency response directly knew exactly where to go and what to do if a road accident occured? During the last ten years the number of motorcyclists in Sweden has doubled. Every year, more than 300 riders are seriously injured and over 40 die in road accidents. Being found in time is critical to increase the chance of survival. The goal of this project is to use design methods to find a solution that enables a fast and adequate emergency response for motorcyclists and other unprotected road users..

Observatörer för skattning av verktygspositionen hos en industrirobot : Design, simulering och experimentell verifiering

This thesis approaches the problem of estimating the arm angles of an industrial robot with flexibilities in joints and links. Due to cost-cutting efforts in the industrial robots industry, weaker components and more cost-effective structures have been introduced which in turn has led to problems with flexibilities, nonlinearities and friction. In order to handle these challenging dynamic problems and achieve high accuracy this study introduces state observers to estimate the tool position.The observers use measurements of the motor angles and an accelerometer and the different evaluated observers are based on an Extended Kalman Filter and a deterministic variant. They have been evaluated in experiments on an industrial robot with two degrees of freedom. The experimental verification shows that the state estimates can be highly accurate for medium frequency motions, ranging from 3-30Hz.

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