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1549 Uppsatser om Strength of materials - Sida 1 av 104

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This technical report describes the master thesis in material engineering called ?Testing of surfaced hardened materials conceivable for gears and shafts?. The work extents 20 academic points. Land systems Hägglunds manufactures and sells different kinds of combat vehicles and terrain vehicles. Since the demands for bigger and stronger vehicles increases all the time, so are the demands on shafts, gears and other transmission details.

MUSKULÄR STYRKA VID MULTIPLA REPETITIONER: : SKILLNADER VID STYRKETEST I BÄNKPRESS OCH LIGGANDE BÄNKRODD MED SKIVSTÄNGER AV OLIKA DIAMETEROMFÅNG

Introduction: A complex interaction between muscles, tendons, bones, joints and nerves are required for optimal function of the human hand. It is known that an individual?s grip strength is vital for performance of physical demanding tasks such as strength training with free weights. Strength training including a thicker grip around the bar may enhance the strength of the grip in the athlete without other special routines for grip strength development. The purpose of this investigation was to examine the difference in performance in multiple repetitions in two strength training exercises using two different sizes on the bar, to look for correlations between grip strength of the subjects hand and the amount of repetitions executed with two different size of the bar and finally the correlation of hand size and the amount of repetitions executed with two different size of the bar.Method: 15 strength training men (23,9 ± 4,1 years), underwent measurements of hand size, maximum grip strength, 1 repetition maximum (1RM), a 80 % of 1RM weight strength test with two different  bar sizes.Results: The results from the present investigation indicates a 21,1 % reduction of 80 % of 1 RM weight performance in repetitions executed in the bench press with the thicker diameter of the bar and a 66,2 % reduction in repetitions executed with a 80 % of 1 RM weight in the lying bench row with the thicker diameter of the bar.

Eurocodes : Beräkningsjämförelser mellan eurocodes och BKR

In the year 2010 a transition will take place here in Sweden from the present rules how to dimension buildings in to the common rules with have been developed in Europe, the Eurocodes. Eurocode is the term for a collection standard that contains calculation rules in how to dimension constructions and buildings. They are developed by the European standardize committee.The purpose with this examination work is to get an insight of what changes this will contribute to, and how it will affect the dimensioning. Are there going to be any differences in the dimension you finally chose?To investigate these possible differences two constructions will be calculated first in the present Swedish rules, and then in the coming eurocodes.One of these two constructions will be build completely in steel, while the other will be build completely in concrete.

Hur påverkar byggnadsmaterial av stål en induktiv hörslingas fältstyrka samt frekvensgång?

This research analyzed differences in measurements of magnetic field strength and frequency response in five audio induction loops installed in rooms of wooden construction materials and five audio inductive loops installed in rooms of steel reinforced concrete constructions. The inductive loops were installed at floor level and the measurements were made at the listening height of 1.2m. Measurements of background noise, field strength and frequency response were made at fifteen different measurement points across the room. The research measurements showed that there are differences in field strength and frequency response between these two conditions, whether the audio induction loop is installed in a wooden construction or the audio induction loop is installed in a reinforced concrete construction. The results had a significance level of p=0,05..

Konstruktion av efterbehandlare

The purpose of this report is to examine various roof structures that can operate in a warehouse with large spans. The building that is examined in the report is currently under construction, and the roof construction has already been selected. The selected roof system will therefore be compared with some other structures and materials that have been possible. The report will evaluate three different frame materials, two insulating barriers and two overlaying materials. Another important part in major construction projects is the roof safety.

Jämförelsestudier av Takkonstruktioner med Stora Spännvidder

The purpose of this report is to examine various roof structures that can operate in a warehouse with large spans. The building that is examined in the report is currently under construction, and the roof construction has already been selected. The selected roof system will therefore be compared with some other structures and materials that have been possible. The report will evaluate three different frame materials, two insulating barriers and two overlaying materials. Another important part in major construction projects is the roof safety.

Den ultimata träningsmetoden?

Crossfit is a recently developed form of training which is based on a number of functional resistance exercises performed at high intensity, often to the point of muscular failure. Crossfit has since its introduction 30 years ago, reached vast popularity all around the world, including Sweden. Its practitioners considers Crossfit to be an effective training method for achieving a functional and total trained physique thru improvements in VO2max, muscle strength, endurance, balance and speed. Few scientific studies has been published in the subject which is why this study sets out to examine the effect of Crossfit on VO2max (measured with Åstrands submaximal cyclingtest), maximal strength capacity in lower- and upper body muscles (measured with 1 RM tests in bench press and leg press), rapid strength capacity and strength endurance capacity in upper body muscles (measured with push-up test in 30 seconds) and explosive strength capacity in lower body muscles (measured with sergeant jump test). Five women with an average of 33(±5) years of age all new to Crossfit, performed these tests at two separate occasions with a training period of four weeks consisting of 12(±3,67) Crossfit sessions in between.The result showed a significant improvement in the maximal strength capacity of the leg extension muscles (p=0,025).

Effekter av muskeluppbyggande träning på muskelstyrka och funktionsnivå hos personer med Multipel Skleros: en litteraturstudie

Multiple sclerosis (MS) is one of our most common neurological diseases. The development of the disease often make the affected persons live with it for a long time. There are two types of the disease, the first is a progressive type and the other is relapsing remitting. Strengthening exercises isn?t commonly used as a treatment method although muscle weakness and fatigue are common symptoms.

Bildernas byggstenar : En studie om pixlar och vektorers egenskaper i form av digitala material

With a new digital world that runs parallel with our physical one, we are also facing a new type of architecture and new materials that this new architecture is built on. In this thesis I examine pixels and vectors, two of the digital materials used to create pictures. By approaching them as digital materials, I have mapped their different qualities, when and where one or the other is more or less applicable and the reason behind it. My main research question asked was the following: Are the (digital) materials challenged outside their primary fields of application, and in that case, in which way? With this question in mind, I carried out a semiotic picture analysis on four pictures, later on dividing them into four different categories, based on their different qualities and their ability to deliver information.

Inverkan av flisig krossballast på betong

Concrete is one of the world?s most common construction materials and is composed of 70-80 % stone material. Today crushed stone is used as aggregate in concrete in order to replace natural aggregates due to strong environmental reasons. Stone crushing yields flaky material and in this thesis studies are made on the flaky particle shape and how it influence properties of concrete such as workability, rheology and strength. The concrete recipes used in this thesis have fixed values, the only variable is the flakiness of the crushed stone.

Finns det någon variation i CMJ som återföljs av förändringar i någon av pulsvariationerna och handstyrkan?

IntroductionSuccessful training is a key for athletes to make progress in their development. Training must not just involve overload, but also must prevent the combination of excessive overload plus inadequate recovery. Athletes can experience short-term performance decrement without severe psychological or lasting other negative symptoms. Too much hard exercise or too little sleep can cause overtraining, a condition in which the subject can prevent to be away from the sport for several weeks or months. Previous studies have detected that it is important to avoid overtraining.

Landet lagom och dess "lagomläromedel" : Om jämställdhet och genus i grundskolans läroplaner och läromedel från olika årtionden

The purpose of this study is to examine two educational materials from different decades, to see if they have a conscious gender and equality perspective, and to see if they have followed the development society made regarding gender and equality. Even the curricula have a part in my study as I will relate them to the educational materials. Equality as a concept means briefly that women and men should have the same conditions, and gender depicts our notions of femininity and masculinity.I have chosen to do textual analyses, focusing on multimodal discourse because I analyze both text and image. I also use both quantitative and qualitative methods.My questions are: In which way do the curricula and the educational materials express equality?; In which way do the curricula and the educational materials express gender?; Do the educational materials express the fundamental values written about equality and gender in the curricula? And, if this is the case, does it mean that educational materials have followed the development of the Swedish society?The conclusion of this work is that equality and gender are presented as goals in both curricula, but the new curricula have developed that section more.

Dynamisk styrketräning av M : Quadriceps femoris hos personer i övre medelåldern

AbstractElderly people are going to be a growing number in Europe. Between one third are going to be 60 years or older at 2025. For Sweden the situation is going to be similar. A reduced muscle function could lead to complications for the individual to perform daily tasks and will lead to a higher rate for falling and getting bone fractures. The positive sides are that for men and women there are a possibility for maintaining physical function and strength even in older years.

Icke utövande Kvinnors relation till styrketräning : Om Kunskap, Fördomar, Arbetsgivaruppmuntran och Manslukt

In this study it has been investigated what is missing in non-strength training women to begin exercise regular strength training. It has also examined the level of knowledge about the health benefits and the employer's encouragement to maintain good health. The study was designed in a qualitative methodology and data collection was designed in form of semi-structured interviews. Six women were interviewed between the ages 22-51år. The results showed that women possessed a very low level of knowledge about strength training and also fears and prejudices existed among them.

Analys och dimensionering av robusta kilspårsförband

This master thesis comprises analysis and dimensioning of a keyed joint between a generator axis and a hub with aid from the FEM-software ANSYS Workbench 13.0.The generator axis is a part of a hydroelectric power station that generates electricity with a reactions turbine, a Kaplan turbine. The existing keyway consists of one parallel key with the width 90 mm and height 45 mm. Due to a planned increase of the power of the generated power with 32 % a design study was needed to see if the keyed joint would be suitable for the extra force. Because of the fact that the axis diameter is bigger than the standards covers/recommends a the keyway had to be re-dimensioned. In an earlier assignment from Skellefteå Kraft AB to Sweco Energuide the keyway was planned to be properly dimensioned, but no final solution was approved.During this master thesis a number of different numerical tests were made.

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