After the mandatory rules for clearing was removed in 1994, the clearing area has increased in Sweden. After the storms Gudrun and Per, the areas became planted with new plants, mainly spruce, but also other tree species. Storm areas are now being invaded by naturally rejuvenated birch in the tilling tracks. Since the birch often is initially growing faster than the spruce it is inhibiting the growth and is also damaging the spruce. The purpose of this thesis is to study the new brush saw with chain and compare it with the conventional clearing saw, mainly in terms of performance and ergonomics. The results show that the new brush saw with chain is very good in almost all clearing operations compared to the conventional clearing saw.

The demands for higher production yields and better quality materials from the forests are increasing globally. Tree breeding programs are directed to meet the future demands on forests. In order to capture the full benefits from the breeding programs, clonal propagation is necessary. For most conifer species, somatic embryogenesis (SE) is the only available option for large scale clonal propagation of Elite clonal material. For Norway spruce (Picea abies L.

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.

Radio Frequency Identification, RFID, is a convenient way to enable contactless identification which does not require any physical nor optical contact. As with any radio-based communication the signal can be intercepted, thus making the technology vulnerable to several kinds of attacks. Interception of communication is not the only threat. Since RFID tags might contain personal information or information that will grant the owner access to secure areas, skimming and spoofing attacks are also major threats against this technology. In this thesis report,  the perspective of an adversary is portrayed in an RFID-enabled environment by presenting where RFID is used and how it could be abused.

Grasslands which have been actively managed for a long time and which in modern times have not been subject to cultivation such as fertilization are called semi-natural grasslands. These rare and species-rich areas hold an ecological, biological and historical value and if the management stops these areas will likely diminish. More effective agricultural systems and a declining number of grazing animals have in Sweden, among other countries, made semi-natural grasslands less valuable as foraging areas. Shrubs and fast growing plants rapidly colonize abandoned semi-natural grasslands, threatening biodiversity. The objective of this experiment was to determine the effects of breed and season on diet composition, with special reference to four competitive species found in wet areas ? in cattle grazing heterogeneous semi-natural grasslands ? and thereby contribute to improved management of these areas.

The control of indoor temperature must be able to handle large time constants and both measureable disturbances like outdoor temperature, and non-measurable disturbances, like waste heat from appliances. Due to cheaper microcontrollers (small computers with designated tasks) with better performance, more advanced and computation-demanding methods for control can be used.In this thesis, Generalized Predictive Control (GPC) has been implemented and tested on a theoretically derived model of a house. GPC states that a model of the system is estimated in every sample, and the control is carried out simultaneously, based on predictions of the model. Disturbances like solar radiation can be estimated and used in the control as well. The control signals are determined by quadratic programming, which makes it possible to consider conditions, for example limitations on the control signals.GPC requires a number of parameters to be defined, like model order and control signal penalty, but is relatively robust for variations in them.

This thesis studies the stock price reaction around 68 announcements of special dividends and share redemptions on the Swedish stock market between the years of 2003 and 2007. We show that for the Swedish private investor, the tax effect of a share redemption is lower than that of a special dividend. Moreover, a share redemption could be interpreted as a signal of undervaluation. These two factors lead us to assume that the stock market would react more positively in connection to the announcement of a share redemption. We test this hypothesis through an analysis of the risk-adjusted abnormal return for the observations in the sample.

After the mandatory rules for clearing was removed in 1994, the clearing area has increased in Sweden. After the storms Gudrun and Per, the areas became planted with new plants, mainly spruce, but also other tree species. Storm areas are now being invaded by naturally rejuvenated birch in the tilling tracks. Since the birch often is initially growing faster than the spruce it is inhibiting the growth and is also damaging the spruce. The purpose of this thesis is to study the new brush saw with chain and compare it with the conventional clearing saw, mainly in terms of performance and ergonomics. The results show that the new brush saw with chain is very good in almost all clearing operations compared to the conventional clearing saw.

Människor tenderar att attribuera framgångar till sig själva och misslyckanden till externa källor, fenomenet kallas för Self-serving bias. Hur individer attribuerar kan enligt forskning påverkas av bland annat graden av självkontroll samt självkänsla. Enligt forskning kan intentioner eller beteendemål aktiveras automatiskt och omedvetet av en utlösande signal, så kallad priming, och därmed aktivt guida en persons självreglering. Denna studie har genom ett experiment, med 56 högskolestudenter, undersökt om priming av självkontroll och självförtroende kan påverka hur en individ attribuerar vid framgång och misslyckande. Resultatet visade ingen signifikant skillnad mellan priminggrupperna.

This report discusses developing a software log tool for analysis of industrial processes. The target was to develop software that can help electro Engineers for monitor and fault finding in industrial processes. The tool is called PLS (Process log server), and is developed in Visual Studio.NET Framework 2005. PLS works as a client with Beijer Electronics OPC Server. The program is able to read data from PLC (Programmable Logic Controller), trough the OPC Server.

The Pallas cat is a small cat living in central Asia. The cat is approximately the size of a domestic cat but the Pallas cat is more stocky build and has a much thicker fur that enables the cat to live in a climate with temperatures plummeting to -50°C. The thick fur is one of the reasons this cat has been a popular game for hunters in the past. Nowadays there are other threats to the Pallas cat. One of the major threats today is the reduction of food sources.

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.

To be allowed to sell Z-suspended vehicles with dipped beam Xenon or LED lighting, Scania have to develop automatic headlight level control. This master?s thesis aims to be the foundation to that development.The thesis consists of several parts; a market analysis of how competitors to Scania and the general vehicle industry solve this problem; several available principles for detecting the amount of control needed; the construction of a test station for sensors, a control unit and components connected controlled by the control unit; a further theoretical and practical development of one principle ? one rotational sensor connected between the chassis and the back drive axis; a state flow model programmed in Simulink that produces the control signal for the headlight leveling from the sensor input.Lastly the thesis gives some recommendations to the further development and implementation of automatic headlight level control on Scania vehicles..

AbstractThis report is about the creation of a test system for development of a control system for a off the shelf RC-helicopter, which can be bought for about two thousand SEK. The test system consists of both electronics for controlling the helicopter and mechanical constrainer. The constrainer is used for mounting the helicopter so that it won´t crash.A circuit board including processor and sensors was manufactured. This was used for doing test of the different control algorithms. In this way were we able to analyze the quality of the sensors chosen, and what other sensors that could contribute to the control of the system.Basic helicopter control have been studied and presented in the report.

The rainforests of the world are important not only to the countries in which they grow but to the world as a whole. They influence oxygen and water circulation as well as carbon sequestration which in turn affect global radiation and global warming. The forest also have great value and in Malaysia as in many other tropical countries large volumes are harvested which leaves great areas of degraded forest with little growth and biological diversity. Due to their low financial value these forests are often transformed and used for other purposes than forestry such as oil palm plantations. The trees are often transported out of the forest using large bulldozers. They are heavy which causes compaction of the forest floor and during transport the top soil layers are moved to improve mobility.