This study aims at examining if abnormal returns have existed on theSwedish stock market surrounding the ex-dividend period between the years2002 and 2006. The ex-dividend period that is studied is the ex-dividend dayplus the following five days. The stocks that have been studied are the thirtymost traded stocks which together constitute the index OMXS30.Furthermore, the study investigates if the size of the dividend has an effecton the size of the abnormal returns.Previously performed studies on both the Swedish stock market and foreignstock markets have shown that abnormal returns exist during the ex-dividendperiod. However, the results from these studies are not unambiguous, why itis interesting to follow up these studies with a new study.The method used for investigating the existence of abnormal returns aroundthe ex-dividend period has taken its starting point in the previouslyperformed studies. However, some changes have been made in order tocalculate for differences in risk between different stocks (using beta) whichhas been neglected in the previous studies.The results of our study are that abnormal returns have existed for four outof six days in the ex-dividend period when calculating a mean value over allfive years.

This study aimed to investigate whether there was a correlation between an individual?s selfesteem and search for confirmation on social media. The study also sought to answer whether there were differences in self-esteem and search for confirmation from a gender perspective. In this study social media was defined as Instagram. The choice was founded on the basis that Instagram in the current situation is one of the world's largest social media that allows users to share their everydaylife in pictures, which are commented and ?liked? by other users.

This study was made on former agricultural areas that had been planted with spruce or pine, in the county of Västerbotten. The goal of the project was to investigate suspected deficiency of boron in these areas. Several objects have been reported for possible deficiency and some of these have the characteristic symptoms of boron-deficiency. The hypotheses are that 1) Boron deficiency is present at several of the investigated objects. 2) Planting of forest on cultivated postglacial sediments leads to a successive podzolisation with a decreasing content of organic matter in the mineral soil, due to decomposition, and a decreasing pH in the soil, even on locations that have been added lime. To be able to confirm or reject the hypotheses a number of tests were performed.

This thesis has been carried out in cooperation with a company which develops mobile sensor platforms. The sensors measure different types of data such as temperature, pressure etc.. They will communicate through the internet with a server that stores data in a database. This system will be controlled and monitored through a web page. The project's aim has been to develop this system and to implement a server, a database, a website and a client application that simulates sensor signals.

The use of spread spectrum signals has increased dramatically in military applications. Finding methods for detecting and positioning of these signals have become interesting research areas for signal intelligence purposes. One method is to measure the time difference of arrival (TDOA) that occurs when two receivers are synchronous and spatially separated. Based on the TDOA-technique an audio-demonstrator has been developed and implemented. This report describes the theory for how sound received in microphones can be used to extract information about the transmitter?s position from the measured time difference.

The research group Soil and Water Management at the department of Soil and Environment at theSwedish University of Agricultural Sciences in Uppsala are studying greenhouse gas emissions fromcultivated peat soils. To measure carbon dioxide emissions from peat soils in the field the researchgroup are now using two portable carbon dioxide meters (Vaisala GMP343). For practical reasons,they plan to acquire a new type of automated field meter. The aim of this study is to evaluate thepresent meters to see how environmental conditions and instrument settings affect the results,which is meant to facilitate the introduction of the new field meter when the meters needs to becompared. As a part of the study the relationship between groundwater level and carbon dioxideemissions from peat soils will be investigated.The evaluation of the two carbon dioxide meters was made by connecting them to one single airtightsystem, with the aim of creating identical measurement environments.

Information security is an essential part of all information systems; especially in large organizations and companies dealing with classified material. Every large information system has an architecture that includes many parts that together form an Enterprise Architecture. The aim of this thesis is to study how to describe several security functions in an Enterprise Architecture and also how to ensure accountability between requirements and the implementation of the security functions. The description is for stakeholders on a conceptual level rather than a technical level. The study has been carried out by comparing the theoretical framework that has been formed by a study of the literature, and the empirical framework that has been formed by a group discussion and interviews with Information Security Consultants from Combitech AB.

Usability studies are not a central field of research in library and information science. Although literature in library and information science treats the importance of usable user interfaces quite extensively, the literature does not significantly treat potential problems in measuring usability. The aim of this master thesis is to investigate, through a critical analysis, the methods used when conducting usability studies in library and information science. The critical analysis is based on potential problems in measuring usability identified through a literature review from the field of studies Human-Computer Interaction, the concept of usabilitys original domain. The material which is to be analysed, is chosen from one library and information science journal Journal of the American Society for Information Science and Technology.

Sweden have 419 000 km road in the country and about half of these roads is forestroads. The forest road net most important mission is to make it possible to deliver wood from the forest to the industries. With a raw material that is spread over a large area the road network is important. Each year has the forest road network been extended with about 1 700 km new roads. To decide if a new road is to be built different forest road cost estimation models has been used.

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

Milk yield levels in dairy cows are influenced by many factors such as nutrition, breed, health status, management and environment. This study was conducted among small scale farmers in Zambia, where the climate can be dry for up to six months per year and cause a lack of green pasture for livestock and on-farm produced feed. The purpose of this study was to identify management factors that can influence milk yield at small scale dairy farms in Zambia, and present advice that could improve productivity, without the need of expensive investments. The study included semi-structured questionnaires presented to the farmers (n=29) including questions about cattle management and milk production. Testing of somatic cell count (SCC) with DCC (DeLaval Cell Counter) from herd milk samples (n=56) and observation of housing and animal body condition on-farm was also made.

A study has been performed that investigates the variation of iron content in groundwater.The study was initiated by Midvatten AB, which noticed that the iron content in groundwater samples can vary greatly over small distances. The purpose of this study was to geochemically and geohydrologically determine the factors that influence the content of iron and manganese in groundwater from a selection of eskers in Dalarna, and determine how to best sample groundwater with the method used by Midvatten AB. An evaluation was made of how the vertical variation in soil material, water composition, pumping time and pipe material affects the content of iron in groundwater. Piper diagrams were used to study the relationship between the chemical composition of the groundwater and the content of iron and manganese in groundwater samples from the studied areas. The groundwater from the studied areas was then classified in the Piper diagrams, according to the content of the major ions.

In this thesis, a computer program that in a simple way can calculate the performance of control loops at the refinery Preemraff Lysekil has been created. The computer program has been adapted to the environment at Preemraff Lysekil. Theories for evaluation has been studied in aspect of reliability and of automatic implementation. The evaluation has been carried out from data collected directly from control loops at the refinery and from simulated control loops with implemented errors. Among the studied methods are Harris index and Stattin´s oscillation index.

Vattenfall and Svenska Kraftnät perform start-up tests, where hydropower generators are used to power up the electrical grid in case of a blackout. To monitor the electrical grid, Phasor Measurement Units (PMU) are used. Each PMU is individually equipped with a GPS-receiver to precisely timestamp the data relative to the official time UTC. During the test, it is also of interest to timestamp the measurement signals from individual hydropower generators to later compare with PMU-data, and thus study the power grids impact on the generator. The aim is to work out an appropriate method to make these measurements and to build a data acquisition system, capable of timestamp data relative to UTC, from a generator in one of Vattenfalls hydroelectric power stations. The problem is that the generator is located in an underground station which hampers the reception of GPS-signals and wiring should be avoided if possible. Time synchronization has been solved by using Vattenfalls network, which is synchronized by the network protocol NTP.

Risk-based sampling program of microorganisms in the water source in northern SwedenAfter several disease outbreaks caused by parasites in the drinking water during the last years, it is more essential than ever to insure that the water supply companies have enough barriers to counteract the presence of microorganisms in the outgoing water. It is also discussed whether climate changes such as increased precipitation can have a connection to the increased cases of parasites in water sources. The water source at Gäddvik is Luleå municipality?s largest and provides drinking water to 64 500 of Luleå?s 74 000 inhabitants. The investigation of microorganisms in the water source, especially in the Lule River has not been as prioritized as the sampling of chemical parameters.