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586 Uppsatser om Muscle strength - Sida 11 av 40

Viktoptimering av ett kompositchassi till en multimodal lättviktsfarkost

This report describes the master thesis project ?Weight Optimization of a Composite Chassis for a Multimodal Lightweight Vehicle? which is a part of the Master program in Naval Architecture and a part of a research project at the Centre for Naval Architecture, KTH. Demands on smart and energy efficient transport solutions are continuously increasing. In the Stockholm region the citizens are expected to increase with 25% and the road vehicles with 80% until 2030, putting high demands on the traffic system. Using a small multimodal vehicle deals with this problem and uses both the land and waterways for transportation.

Bindningsstyrkan mellan glaskeram och ett laboratorieframställt stansmaterial. En in-vitro pilotstudie.

Introduktion/Syfte. Intresset för och användandet av adhesiv cementering av keramiska material har ökat under de senaste åren. Detta har lett till ett ökat intresse att kunna jämföra olika studiers resultat med varandra och därmed har även intresset för att utveckla internationella standarder inom forskning ökat. Syftet med denna studie var att jämföra den adhesiva bindningsstyrkan mellan ett laboratorieframställt material innehållande kvartsmjölsförstärkt epoxyresin (Sipoxy), med emalj och dentin. Detta för att avgöra om Sipoxy kan användas som en standardiserad ersättning istället för tänder i in vitro studier som utvärderar bondade keramiska rekonstruktioner. Material & metod.

Optimering av sintrade kugghjul

Powder Metal (PM) gears are machine element components which operate under the same principle as conventional gears, but, due to their intrinsic material characteristic need to be designed slightly different, and its manufacturing process offers advantages previously unobtainable by conventional steel gear manufacturing methods. The use of PM in similar applications, such as synchronous hubs, makes them a suitable candidate for production in such material. The current master thesis work focuses on gear design using PM by utilizing finite element method (FEM) to reduce weight and inertia taking into account root bending strength and tooth deflection.First a topological optimization is used to determine feasible candidates for different web designs which have as objective to reduce volume, similar topologies were shown during different loading conditions; and hence, this topology was chosen as a suitable candidate. A shape optimization of the topological candidate was performed having as state variables root bending strength, independent for compressive and tensile side of the tooth loading; and tooth deflection, which in concept can be correlated to static transmission error (TE).Another aspect in this thesis analysed is the possibility to incorporate non-trochoid root geometry, a trochoid root is always present when machining with a hob, into the gear root and hence reduce the stress concentration here. Due to the use of PM, a non-symmetric optimized root can be achieved and hence be optimizing compression and tension.Results showed significantly lower inertia, for example certain results showed 40% reduced when compared to solid gear, with adverse effects as increase in tooth deformation and increase in maximum principal stress.

Stamskador i gallringsbestånd

This study was conducted on a property with a thinning machine team. The purpose was to investigate in which machine, the harvester or the forwarder, that caused most damage to the trees in six different stands. Different factors, related to the damage frequency in the stands, were checked out. For example: basal area per hectare, thinning strength, tree diameter and the rate of production. The harvester drivers were also interviewed about how, when and why stem damages occur and how to minimize them. The study stated that 4.3 percent of the trees were damaged. Out of these 88 percent was caused by the harvester and the rest, 12 percent, by the forwarder..

Effekten av ett sammanlagt nio veckor långt plyometriskt träningsprogram på accelerationsförmåga, snabbhet i riktningsförändringar och kraftutveckling hos manliga juniorishockeyspelare

Ishockey är en explosiv idrott och plyometriska övningar främjar explosiviteten, en ishockeyspelare behöver explosiv styrka för att prestera på isen. Syftet med den genomförda studien var att genom ett sammanlagt nio veckor långt plyometriskt träningsprogram, under off-season perioden, undersöka effekten på accelerationsförmåga, snabbhet i riktningsförändringar och kraftutveckling i nedre extremiteterna hos manliga juniorishockeyspelare. Totalt deltog åtta manliga juniorishockeyspelare. I undersökningen användes mätinstrumenten Harres test, Muscle Lab model 4000 (Ergotest Technology, Norge), 10 meter Sprint test och Power and Force explosiv knäböjning i Smith-maskin. Resultatet visade på signifikanta samband mellan för- och eftertestet för riktningsförändringar.

Fågel fisk eller mittemellan?

The project is a thesis which intends to strengthen the form language and increase the user friendliness of an International Moth. This is a single handed dinghy with only one sail. It sails on two hydrofoils and receives a very high speed compared to its size, and are therefore often referred to as ?the Formula One on water ?. The result is a new concept where the aerodynamic forces have been used to stabilize the boat and relieve the hydrofoils.

Lärares erfarenheter av arbete med elever som far illa

The purpose of this study was to investigate the association between physical activity and perceived stress, energy and musculoskeletal disorders among office-workers and warehouse-workers and also to see if there were any differences depending on work-place and gender. The method that was used to collect data was three different validated questionnaires that measured stress and energy (the Stress-Energy questionnaire), musculoskeletal disorders (intensity and localization of pain, a Pain Drawing questionnaire with a VAS-scale) and physical activity (IPAQ ? the short version). Eighty-eight workers participated in the study. Forty-seven of them were office-workers and forty-one were warehouse-workers.

Högtrycket-Initierande undersökning av nytt limträmaterial

The present study examines a new production line of glue-laminated wood (glulam). The glulam is produced from non-planed boards of spruce, which also is convex, that is pressed together with high pressure during the gluing. According to a economic calculation, the material has a economical potential mainly on account of the absent planning. The study mainly found out that the shear strength of the material tolerated the demanded values in standard SS-EN 386, but the delaminating values did not. Since there are more areas to be studied around the material, the prospect to achieve the right delamination values is seen as positive..

Den djupa muskelfunktionen hos kvinnliga elitvolleybollspelare : En studie om transversus abdominis funktion påverkas av stabilitetsträning.

Background and purpose: Volleyball requires a lot of the human body, andeffective core stability is necessary for the athlete. Our muscles cooperate as achain of motions and core stabilization is the base for the moving muscles.The most well-known stabilization muscle is m.transversus abdominis (TrA).The purpose of the present study was to evaluate the function of TrA inSwedish female elite volleyball players and to observe the influence of eightweeks of stabilization exercise on the TrA. Method: 10 female elitevolleyball players (mean age 24,7 years, range 18-31 years) participated inthe study. TrA was measured in supine position with a pressure biofeedbackunit. Subjects were instructed to draw in the abdominal wall without movingthe pelvis and hold for 10 seconds.

Behavioral studies in healthy Standardbred trotters subjected to short term forced recumbency aiming at an adjunctive treatment in an acute attack of laminitis

Laminitis is a debilitating disease causing much suffering to horses and ponies all over the world. It is manifested in the hooves as a mechanical failure of the suspensory apparatus between the hoof capsule and the distal phalanx. Due to the weight of the horse the disease may result in a dislocation of third phalanx. Six healthy standardbred trotters were used in this study on whether standardbreds tolerate forced recumbency as well as Shetland ponies. Recumbency was induced pharmacologically but maintained only by lowering the ceiling height of the box to a height of approximately 125 ? 140 % of the horse´s thoracic height.

Elevers uppfattningar om kunskap, motivation och undervisning kopplat till SO-ämnena

The purpose of this study was to investigate the association between physical activity and perceived stress, energy and musculoskeletal disorders among office-workers and warehouse-workers and also to see if there were any differences depending on work-place and gender. The method that was used to collect data was three different validated questionnaires that measured stress and energy (the Stress-Energy questionnaire), musculoskeletal disorders (intensity and localization of pain, a Pain Drawing questionnaire with a VAS-scale) and physical activity (IPAQ ? the short version). Eighty-eight workers participated in the study. Forty-seven of them were office-workers and forty-one were warehouse-workers.

Cutaneous Melanoma in the Grey Horse

Equine cutaneous melanomas arise much more often in horses with a grey coat color than in horses of other colors. Some scientists have in different studies come to the conclusion that the melanomas are neoplasms which can be classified by examining their histological and macroscopic features. The more defined and demarcated a tumor is, the more benign it tends to be. Other scientists believe that the skin lesions are the result of a pigmentation disorder that is linked to the greying of the coat color. According to this theory, the lesions are not malignant although they have the ability to metastasize.

Konstruktion av statorstomme för synkrongenerator : Förslag på design av statorstomme för användning i vertikalaxlade vindkraftverk

This thesis describes a conceptual design of a support frame for a synchronousgenerator used in a vertical axis wind power plant. In this system the generator isplaced on ground level. The thesis also considers the design of housing for thesupport frame and generator. The concept presented in this report is based on anearlier design. Besides geometric design, simplified simulations has been run in orderto optimize some of the parts included in the construction considering naturalfrequencies and structural strength.The result is presented as CAD-models andan assembly drawing..

Elever som inte når målen i de samhällsorienterande ämnena : Orsaker och insatser i grundskolans tidigare åldrar

The purpose of this study was to investigate the association between physical activity and perceived stress, energy and musculoskeletal disorders among office-workers and warehouse-workers and also to see if there were any differences depending on work-place and gender. The method that was used to collect data was three different validated questionnaires that measured stress and energy (the Stress-Energy questionnaire), musculoskeletal disorders (intensity and localization of pain, a Pain Drawing questionnaire with a VAS-scale) and physical activity (IPAQ ? the short version). Eighty-eight workers participated in the study. Forty-seven of them were office-workers and forty-one were warehouse-workers.

Muskelstyrka i lårmuskulatur efter operation av främre korsbandet ? finns skillnader avseende ålder och kön?

Det finns idag ingen konsensus om den optimala rehabiliteringen efter en främrekorsbandsrekonstruktion, vi vet heller inte idag huruvida rehabiliteringen skaspecificeras efter parametrar som kön och ålder. Studien var en korrelerandetvärsnittsstudie med syfte att ta reda på om det förelåg någon skillnad i postoperativlårmuskelstyrka 4-7 månader efter en korsbandsrekonstruktion med avseende på kön,ålder, skada och typ av operativt ingrepp. Av de 330 aktuella försökspersonerna var detendast 74 personer som godkänt deltagande och uppfyllde kraven förinklusionskriterierna. Försökspersonerna testades i en isokinetisk dynamometer(Biodex)för maximal styrka(60gr/s) och uthållig styrka(180gr/s). Resultaten presenteradesgenom ett Limb Symmetry Index.

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