Sök:

Sökresultat:

4044 Uppsatser om Hypothesis testing and t-test - Sida 36 av 270

Mixture and single-compound toxicity using Daphnia magna : comparisons with estimates of concentration addition and independent action

Aquatic organisms are usually not exposed to single substances but rather to mixtures of toxicants in streams located in agricultural areas. The transport of pesticides used in the agricultural area in Sweden is monitored with continuous environmental supervision every year. During 2002-2008 an average of 10 pesticides were found in each sample and 40% of the samples contained substances with concentrations higher than the Water Quality Standards. Chemical risk management is normally based on single-test evaluations. A problem when assessing mixture toxicities is that the constituents and concentrations of pollutants in the environment vary greatly.

Adaptivt e-lärande av grundläggande programmering med Live-programmering

e-lärande handlar om hur man ska ha tillgång till lärandeinformation vart man än är, oberoende enhet så länge internetuppkoppling finns. Adaptivt test är ett test som kontrollerar användarens kunskaper för att kunna anpassa t.ex. läroinnehållet efter användarens kunskaper. Live-programmering är då användaren kodar i ett program som ger direkt feedback på vad koden gör.Problemet består utav att utforma en algoritm och en datastruktur som kan utnyttja den data som erhålls från en live-programmerings-miljö för att kunna genomföra ett adaptivt test. Undersökningen kommer att ske i en webbläsare med hjälp av live-programmering.Implementationen av arbetet sköts smidigt genom att programmera en hemsida där användaren får testa de olika algoritmerna.

Användandet av samlingsprover för att bestämma besättningsstatus för smitta med Dictyocaulus viviparus hos förstagångsbetande nötkreatur :

Infection with the bovine lungworm - Dictyocaulus viviparus - is occasionally a problem in Swedish cattle herds. The infection could act in synergism with other infections such as Corona virus to create a poorer welfare and productivity in cattle. Studies have shown that a diagnosis can be made with both the Baermann method and with an ELISA. In Norway diagnosis of BVDV on a herd level is attained through pooled serum samples. The question was raised whether pooled serum samples could be used in a similar fashion to attain status on a herd level for lungworm.

DFM för Lasersvetsning

 The purpose with this thesis was to develop a designguideline which will simplify the development of new products that will be laser welded. The need for this thesis has come forward from the quality problems that Volvo Construction Equipment, Components Division is having with their laser welding manufacturing unit. The reason for the problems emerges from the bad communication between the development unit and the manufacturing unit within the company when the products produced today was developed. This resulted in products that were hard to and in some cases almost impossible to weld. To avoid these problems from occurring again it was needed to gather the experiences within this area and compile it and present in a brief a pedagogical manner. The information for the groundwork of our results has been gathered by interviews of several key persons in Volvo Construction Equipment, Components Division.

Styrtransmission för bandfordon

The purpose of this master thesis is to construct a steering transmission, for a trackedvehicle, containing two hydraulic circuits which are connected. The steeringtransmission should be mechanical to avoid steer-by-wire.BAE Systems Hägglunds has in an earlier study examined a system with two hydraulicpumps and one hydraulic motor, but the safety of the system wasn?t sufficient.To achieve sufficient redundancy there must be two hydraulic motors, which arecontrolled separately. When the two systems are connected in one point, this point is acritical part of the system because it directly affects both circuits. If one of the hydrauliccircuits fails the other should be able to operate independently as a steeringtransmission.

Privatpersoners sparbeteende i Tillväxtmarknadsfonder Ryssland, Kina & Afrika

This paper includes astudy of the mutual fund market investors during a selected timeperiod. The reader is given a descriptive picture of how people in different age groups have  acted  in  conjunction  with  the  last  major  financial  crisis.  It  has  been  studied whether people in the different age categories have saved,purchased or sold during this time  period  based  on  theories  and  analytic  material  from  one  of  the  largest  fund operators in Sweden. The result enlightens people?s activity and risk appetite in relation to the fund market. The essay results in an explanation of the underlying cause of the behavior        of         the         people         in         the         different         age         categories.The paper assumes that the market is cyclical and that more crises will occur in the future.

INFÄSTNING AV LED-ARMATUR

The thesis was performed at the lighting company Zpecta AB. Zpecta needed to develop alternative attachment of their LED-luminaire Capella. Today Capella attaches in metal ceilings with four magnets. Zpecta got indications from their customers that there was a need for other attachments. The purpose is to determine the customer?s requirements and the interfaces that are considered for Capella.During the thesis, Capella was only on the market for testing and evaluation.The thesis was initiated to create a specification.

Truppgymnastik

According to recent research the basics for a good body posture is balance between the muscles, if unbalance originates this can be strengthen by gymnastics when most of the practise performs only in one direction. Because of limited research in the area was an explorative study conducted. The purpose of the study was to inquire if exercise adjusted to the individual contributes for balanced muscles and if it contributes for a positive or negative development for the team.On the basics of that the team is not equable an other team in the area has the results for two different periods been measured, during the first period the exercise continued as usual but during the second period each gymnast (n=9) received an individual strength- and stretch program that was performed during the teampractise twice a week. The gymnasts were tested in areas that are imported for them as body posture, balance between the muscles, vigour, range of movement, balance, the running and coordination. The results showed on that the difference is largest between test two and three, except the coordination and balance which did not show any particular change.

Orden bland drakar och demoner : En språkstudie av svenska rollspelsböcker

The purpose of this essay was to do a research about if the language in Swedish role-playing books is used correctly and if the composition along with the possible language errors makes the books hard to understand.This research was also about to find out why these problems occurs and if the authors are aware of them.I choose books from two Swedish role-playing games, Eon and Drakar och Demoner. I read them trough, noted the mistakes made and put them together in a scoring table. I also did a LIX-test on the books and interviewed one of the authors.The results shows that the books to Eon is harder to read than the books to Drakar och Demoner and this agrees with the vision the authors of the books claims to have.The results also shows that it is not only the language mistakes and the composition that makes the books hard to read, but also the choice of difficult words and badly formulated rules..

Analys, modellering och återskapande av fordonsdynamiska rörelser i tåg

The purpose of this thesis was to analyse, model and finally generate dynamic vehicular motions in a train. The objective with the analysis was to find important motions for a realistic train experience. The motions from the analysis were then weighted against possibilities for generation in a motion platform.A dynamic motion model was created to model the selected motions. The model was implemented in a simulation environment, more specifically MATLAB/Simulink. The simulation environment was used to simulate the model and to generate outputs to control a motion platform.

Aktiv lastbilsstol för bättre förarergonomi och hälsa

The project concerns a predevelopment work for Scania AB, a leading manufacturer of heavytrucks, and was performed as a master thesis work for the program Design and ProductDevelopment at KTH. The purpose of this work was to examine how the work situation of truckdrivers, especially long-haulage drivers, can be improved with respect to prolonged sedentaryoccupation. Mental fatigue and under-stimulation due to low cognitive load during long drivescan be major risk factors for traffic accidents. Physical strain injuries to both the skeleton andmuscles are common for this working group and minimal opportunity for daily exercise alsoincreases the risk of developing blood clots in the legs, which can have serious consequences forthe driver's health.An extensive background study, both theoretical and exploratory, was performed to identify thedrivers' concerns and comfort needs. Various treatments such as massage and active sitting wereinvestigated and existing products within the area studied.

Mätning av mobila datanät i Arvidsjaur

This report presents the results of the tests of data rate and signal strength that I have conducted. The tests have been performed in the municipality of Arvidsjaur, Sweden. The report also contains the conclusions I have drawn from the results as well as an introduction to radio and the technology used in the nets that have been testedThe equipment used is:LG G2 cellphone used to test Telias 3GHuawei b593s-22 3G/4G router used to test Tele2s 3G/4GMobile Broadband Gateway R-90 used to test Net1s CDMAThe data rate has been tested with bredbandskollen (www.bredbandskollen.se). The signal strength(RSSI) has been read in the configuration menu of the broadband routers as well as in the cellphone.The conclussions drawn:Net1s net appears to be more used compared to its capacity than the other netsTele2s net has a high and even data rate where it?s signal strength is sufficient.

Sigma energy app

Sigma energy app is a mobile application for subscribers to various energy subscriptions. The subscribers can use this mobile application to access information regarding their consumption, invoices and active subscriptions. The mobile application that was built consists of a GUI and a web API as middleman between the application and the database.                     .

Avsättningars värderelevans

Introduction: This thesis is about how the accounting entry provisions are linked to corporate market value. By statistically examining accounting and share data for 56 companies listed on NASDAQ OMX Stockholm, the question of whether accounting information regarding provisions are value relevant for investors is studied. Listed companies shall follow the rules of IAS 37 ? Provisions, Contingent liabilities and Contingent assets, when preparing financial statements.Aim: The purpose of this thesis is to examine the relationship between reported information about provisions and investors assessment of listed companies that comply with IFRS-regulations, by statistically testing the value relevance of the accounting entry.Method: The study is based on a quantitative, deductive methodological approach. The value relevance of provisions is examined by statistically testing the collected empirical data based on the two models that is described in the reference frame.Results: The conclusion to be drawn from the study is that reported provisions have no statistically significant association with return on shares and thus is not value relevant.

Olfactory responses of the parasitic wasp, Trybliographa rapae (Hymenoptera: Figitidae)

Delia flies (Diptera: Anthomyiidae) are economically important pests in several horticultural crops. The control is commonly relying on chemical insecticides, though there are possibilities with biological control from the natural enemies in the field. An important natural enemy is the parasitic wasp, Trybliographa rapae Westwood (Hymenoptera: Figitidae) that lays eggs in the Delia fly larvae. The parasitoid larva and the host larva have a parallel development until the host dies within its puparium and an adult parasitoid emerges. The aim of this thesis was to understand the attraction to host- and food-associated plant volatiles of T. rapae, in order to enhance the effectiveness of the parasitic wasp as a biological control agent.

<- Föregående sida 36 Nästa sida ->