Sök:

Sökresultat:

726 Uppsatser om Frequency weighting - Sida 6 av 49

Ulla Molin - Östbergs trädgård i Lund

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.

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.

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.

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.

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.

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.

Hållbar utveckling i Kungsängen : ett gestaltningsarbete med fokus på folkhälsa, biologisk mångfald och ekologisk dagvattenhantering

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.

Social Demokrati : Sociala medier, Politiker och Demokrati

The aim was to explore how the first page of a student newspaper has been changed over time since it was founded in the 1960´s.This thesis explores how the front page of the student newspaper Lösnummer has been changed since it was founded in 1966. It concerns the location and frequency of elements and it is based on theories of layout, the first page and visual communicationIn addition, the thesis develops a new kind of method for determining the location of elements on the type area. The method is based on the hexadecimal number system. It is formed as a grid which is placed on the first page to determine the location of the elements.It concludes that the frequency of elements had its peak during the 1970´s and has ever since decreased gradually. Image placement has gone from being scattered all over the front page to be centered and increase in size. .

A comparison of transporters? paddle use when unloading pigs at slaughter

Today, pigs are moved on farm, between farms, between countries and to abattoirs. This movement of live pigs requires handling practices that are designed for the purpose. The objective of this study was to research the use of paddle in moving pigs, to investigate if there were different methods of paddle practice, explore the time efficiency of different kinds of paddle use and if there were any time variations in methods that varied in intensity of touch. This study was done on two Swedish abattoirs for a total of five weeks. A total of 22 transporters working at two different abattoirs where studied during unloading of pigs at the abattoirs.

Relationen mellan cyklister och fotgängare vid Södra Älvstranden, Göteborg En utvärdering av trafiken på cykelstråket Älvsborgsbron - Centrum

This paper describes a method for wireless energy transfer via near-field electromagnetic inductionthat is inexpensive, simple and can be applied to almost any type of system, regardless of size andenergy demands.The method uses a primary unit consisting of an oscillator, amplifier and inductive coil thattransfers energy to a secondary unit consisting of a coil, rectifier and voltage regulator. Two typesof oscillators and several amplifier designs were realized and evaluated together with a multitudeof flat coils of both monofilar and bifilar type.The results show that it is important to use an oscillator whose frequency is dependent on theinductance of the connected transmission coil, such as the Colpitts oscillator. This is preferable toan oscillator with a preset frequency, such as a Schmitt-trigger oscillator..

Optimering av informationsinsamlingvid prototyptillverkning

This report discusses a method to detect divers in harbour environments usingpassive acoustic detection. The goal was to achieve as high detection as possiblewithout having too high false alarm rate. A short execution time was also desirable.By using the characteristic of an inhalation a band-pass filter was applied to the signalto improve the signal to noise ratio. After the filtering an energy estimation of thesignal was made. This energy estimation was later used in a frequency analysis, whichcould tell us if there were enough energy in the frequencies that correspond to adivers breathing frequency.

<- Föregående sida 6 Nästa sida ->