The animal welfare act in Sweden states that dairy cows need to have at least a dim light present at night, but there are no recommendations for what intensity the light should have. It is unknown how cows perceive and react to low light intensities and earlier studies on this topic are limited. Red light as night light has also been suggested, based on the cows? inability to perceive red light. This have however been questioned. The aim with this study was to investigate how four different light intensities affect dairy cows behavior.

This study is about how changed light conditions induce dormancy in plants. It is divided in two parts. First a literature study where quantification of light, the concept dormancy, photoperiod and light quality are discussed. Second an experimental part, where the importance of light for sprouting capacity in root buds of perennial sow thistle (Sonchus arvensis L.) is investigated.In the science in how flowering in plants are induced the concepts short day/long day plants and light dominant/dark dominant are well-established. These concepts can also be applied to how light induce dormancy in plants.

Automatic milking systems (AMS) provide the opportunity for less manual labour and an increased milking frequency. But in order to reach an optimal milking frequency a well-functioning cow traffic is crucial. There are many factors affecting cow traffic but one factor that has not been studied thoroughly yet is the effect of different light intensities during the night, 22.00 h to 05.00 h. Therefore the aim of this study was to determine the effect of different light intensities during the night on number of selection gate passages (GP), milking frequency and milk yield. The study was conducted as a Latin square were three light intensities were applied: LOW (11 ± 3 lux), INT (33 ± 1 lux) and HIGH (74 ± 6 lux), in three different herds.

Today dairy farmers in Sweden are obligated to have lights turned on during night time in addition to the mandatory daylight inlet. This presents a cost for the production but many argue that it can be economically beneficial, especially in loose housing of dairy cows. In loose housing and even more so in herds with automatic milking, well functioning cow traffic during all hours of the day is crucial to optimise production. In order to keep the cow traffic flowing, lights may be an important management tool. It is also perceived among farmers with tied up stall that night light decreases the incidents of cows accidental stepping on their own or neighbours udders.

Lumilos is a work investigating the possibilities to use light and color in an interactive design context. I have explored different light sources and compared them to each other and given a short description of the history of light and how it has been developed during the industrialization in the western world. I have also investigated what is currently done in the field and summarized that with examples in the categories passive-, colored-, material- and interactive light. The conclusion is that working with interactive color and light is a hard task. There are many different angles to take into account such as personal likings and earlier experiences that is uncontrollable by the designer. Yet there are many possibilities and light is a material that is moldable in many forms. I have put the knowledge about light and color into practice and developed an interactive light wall that is visualizing energy consumption with the use of different colors of light and animations.

During the 1930´s the hot potato for the Swedish lighting associations were how to create the most suitable light for every situation, either for industries, offices or homes. The light bulb were the most frequently used source of light but due to limitied luminous intensity, big halls sometimes required up to hundreds of light bulbs to produce the right amount of light. Two kinds of different lights, by different reasons, can be titled the predecessors of the fluorescent lighting during the 1930´s: The volfram-filament tube light due to its estetic similarities and the electric discharge (mercury- and sodium-) lamps due to its technical resemblance. Even though they came in quite wide use (the volfram tube in public halls (e. g.

Inspired by how to sketch a light cone from a flashlight in a comic I wanted to create an armature carried only by its own light cone. To manage this challenge I sketched in an architectural and sculptural way, where I chose to ignore the function of the lamp as long as possible.As a result I developed an armature with a stunning shape, with an illusion that it was carried by its own light cone. It could be hanged on a wall, placed on a table, pushed against a ceiling or standing on the floor.Depending of its size the light cone from the light source lightens up the surface and draws attention to the otherwise forgotten wallpaper or the undisposed statue in the darkness of the city..

For a few decades, the wild boars are established over large areas in southern and centralSweden. Where they cause problems in terms of damage to crops in the agriculturelandscape, where rooting, browsing and trampling, but also damage to the crop when wildboars chosen daily rest in the cultivated fields. Along with the growing number of wildboars the rate of car accident with wild boars has also increased.Here I examined the daily rests of wild boar (Sus scrofa) sows in southern Sweden, todetermine the factors which the wild boars sows choose for daily rest. By determining whatfactors are important in this selection of daily rests, we may be able to make managementmeasures to reduce the damage wild boars make in the agriculture landscape by attractingthem to places where they do less economic damage and accidents on roads.In this study I have examined 123 daily rest positions from 14 different individual wildboar sows fitted with GPS collared in Southern Sweden, Skåne County in Christinehof,Högestad Kronovalls estate. Data was collared over the years 2004-2006 during the periodfrom June 1 to September 30.

The purpose of this review was to study the cow eye physiology, focusing on how it registers light, and to see how light affects the cow?s milk yield. It has been showed in studies that more hours of light per day (16 hours of light a day) as opposed to about 9-12 hours of light a day, increases milk yield for dairy cows. This review contains suggestions on how this is connected with the physiology of the eye. Vision is an important sense for many mammals, and is used to check out the animals surroundings. Sensor cells in the eyeball help in turning photons from the light into signals to the brain.

When cows in Sweden are inseminated the heat strength is reported to the Swedish milk-recording scheme and AI scheme. Cows that show strong signs of estrus are desirable and the trait is included in the Swedish breeding goal. A strong heat makes it easier to inseminate at the right time and to avoid long and expensive days open. Since ten years the heat strength is scored from one to five by the farmer and reported to the milk-recording scheme and AI scheme. Earlier the score was from one to three and the decision was made by the AI technician.

In this study, we investigate various lighting applications in a virtual environment, where we compare between light based in naturalism (natural light) and pictorialism (artistic light). The purpose of this study is to gain further knowledge in lighting, which is increasingly important for game graphics. Theory are examined to gather information and recommendations on how to use various light settings that convey different emotions. We then use this information to illuminate the environment that we have built. The environment is presented in Unreal 4 for respondents who are allowed to move around freely in the environment.

The relation between the cave and the circumpolar light conditions has long been a part of the interpretation of the meaning of the Norwegian cave art. This paper explores the relationship by trading the concept of a sensory dichotomy between light and darkness for that of a perceptual relationship between the paintings, the environment and the light..

This work is an exploration of a method and how to find balance between it and its contents. One part consists of a technical study on how to use UV light to yellow distinct surfaces on paper and the other is about how to find use of the method. The common denominator is determined as the consequence of the relationship between light and time. The result is three images that shows various traces of time with time as a graphic expression..

The aim of this study was to investigate the relationship between sleep, photoperiod, milk yield and hormones connected to milk formation. Variations of prolactin (PRL) and Insulin-Like growth factor-1 (IGF-1) in plasma were measured during two different light programs. The light programs consisted of either 24 hours of light (L24:D0) or four hours of light and 20 hours of darkness (L4:D20). Five cows of the Swedish Red breed were used in a cross-over experiment and each light program consisted of five days. Milk yield was measured at every milking and milk samples were analyzed with regard to fat, lactose and protein.

Successful broiler production in hot climates requires knowledge of how birds are affected by heat stress. It is important with access to water and good ventilation to facilitate coping with the heat. It may be useful to reduce the consumption of feed during the hottest hours of the days, which together with a few hours of extra light available could improve both productivity and animal welfare. The vision in birds is superior to that of humans and most other mammals. Continuous light and light with low intensity can cause eye injuries, affect the eye development in young chicken negatively, as well as provide increased incidence of foot pad lesions. Access to light affects the production but also the welfare of birds.