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894 Uppsatser om Mechanical properties - Sida 56 av 60
Privata skogsägares inställning till frivilliga naturvårdsavsättningar samt kvalitets- och tillväxthöjande skogsskötselåtgärder :
The business mission of Norra Skogsägarna is to achieve a profitable forestry for the private forest owners. With this as a background it is of interest for the forest owner association to know how forest owners think about voluntary retentions, the methods of increasing production and quality and if there are differences between those who have chosen to certify their forest and those who haven?t. This kind of knowledge is of importance, to in an effectively and adjusted way, help the forest owners achieve a profitable forestry.
The objective of this master thesis is to increase knowledge about private forest owners? opinions of the methods of increasing production and quality and to what extent these methods are used.
Evaluation of an ectomycorrhizal macrofungi as an indicator species of high conservation value pine-heath forests in northern Sweden
Since the 1950s, the development of modern rotation forestry in boreal Fennoscandia has resulted in a severe reduction of older forests, and a high degree of fragmentation among the small patches that remains of old forest. In Sweden, when performing conservation value assessments in order to identify and preserve the remaining forest habitats, the government authorities use to a significant extent a set of indicator species that indicate habitats of high biological conservation value. One species considered to indicate high conservation values in pine-heath forests is the red-listed ectomycorrhizal (EM) macrofungi Sarcodon scabrosus (Fr.) P. Karst. In the present study, the validity of using S.
Design och implementering av ett webbaserat personalhanteringssystem
Quickmatch is a company that recruits students to other companies that need temporary workers. Today all administration is done by hand, which is very time demanding and therefore inefficient. Employees send assignment reports by e-mail about the working hours and breaks to the administration office. Since these reports are handled manually, there is a great need for an automated system that makes the company more scalable.The purpose of this work was to solve the defined problem, i. e.
Muramaris anläggningshistoria 1915-24 :
Gardens from the first decades of the 20th century are often described as seen from a sublime ownership perspective. It may be artists, authors or some other intellectuals, they are all attributed as creators of the referred estate. As far as practically oriented gardeners, constructors or garden consultants are mentioned, they are consequently seen as the mere instruments for carrying out the intentions of the actual owners. Referring to those circumstances it is however well worth notifying that all properties, and in particular the gardens belonging to it, are submitted to a constant change. For anyone acquainted with garden work, it is quite obvious that the gardens vitality is closely related to the ongoing design process, by which form and content are created and re-created.
Förluster av nedströmsvandrande fisk vid turbinpassage : En fallstudie för att främja den småskaliga, såsom storskaliga vattenkraften
The expansion of the Swedish hydro power has contributed positively to the reduction of the environmental impacts from the fossil fueled power production. In the same time the extensive expansion has been proved to cause negative ecological and local environment impacts of a stream. This, in turn, has been affecting the biodiversity and fish stock negatively, which has been reduced. One of the underlying problems is the lack of possibility for the fish to pass the plants, but it is also directly correlated to the mortality rate of the fish passing through the turbine, which this study is investigating.The mortality rate has been computed for three different locations in Sweden, Untra, Tännfallet and a third one whose location is confidential, and is denoted as Case 1, 2 and 3. The model used to calculate the mortality rate in this investigation is based by existing blade strike models and knowledge and are investigating the death due to mechanical injuries from collision with a runner blade in the turbine.
Förslag till modell av kemikaliespridning i mark anpassad för användning vid räddningsinsats - Kemspill Mark 4.0
After emergencies involving chemical spills it is of great importance that correct measures are taken with short notice, both for the security of people and in order to minimize future environmental consequences. The RIB-unit at the Swedish Rescue Services Agency initiated this study, the aim of which is to propose changes to the existing chemical transport calculation tool: Chemical Spill 3.4, included in RIB - Integrated Decision Support for Civil Protection, so that it can be used for decision support as well as in preventive work. A rough estimation of chemical transport in the subsurface is considered being of great importance when making decisions during emergency response operations.The proposition presented in this report is a non site specific chemical transport model which is designed to give a rough estimation of NAPL flow in homogenous isotropic soil shortly after an instantaneous release. The model can be used at two levels; both in situations without access to information on subsurface properties, and with more accuracy in situations with knowledge of the included parameters. For that reason the user can choose among predefined alternatives or assign the parameters a numeric value to increase the quality of the model output.
Termisk hantering av litium-jon- batterier i elektriska drivsystem
The automotive market is currently undergoing a historical change where stricter emission legislations and ever increasing fuel costs have intensified the search for effective alternatives to the conventional internal combustion engine, which has resulted in a substantial trend towards electrification of powertrains. Storage of electrical energy is the fundamental component in this technology where the lithium-ion batteries are currently considered as the most appropriate solution. Lithium-ion batteries, however, as other types of batteries, can only be used efficiently and durably within a specific temperature range.This Master thesis has been carried out in collaboration with Electroengine in Sweden AB, situated in Uppsala, which has an ongoing project regarding development of a modular battery system for electric powertrains. The project is at a stage where an initial prototype has been developed which provides the foundation for this thesis. The study has addressed the battery system performance from a thermal perspective, in order to validate the ability of the system to create a thermally serviceable environment for the lithium-ion battery cells.
Leaf area index in Vittelaria Paradoxa parklands in Burkina Faso estimated by light interception and leaf sampling
Burkina Faso as well as most sub-Saharan African countries struggle with providing food for a fast growing population. The dominating farming system is agroforestry parklands. Agroforestry parklands can broadly be defined as areas where scattered trees occur on farmlands as a result of selective clearing. The presence of trees in crop fields may in the long term have a positive effect on the production of annual crops. It is commonly discussed, but not proven, that the presence of trees leads to increased groundwater recharge due to higher infiltration capacity of the soil.
Korrelation mellan hållfasthet i kalkcementpelare och oförstärkt lera : En studie av sonderingar utförda på projekt BanaVäg i Väst
A today common soil reinforcement method is the installation of lime-cement columns. Lime-cement columns have been used since the 1970?s and have been a useful method for stabilizing soil at great depths. It is mostly used for stabilizing road and railway embankments because the method is economically viable and the columns are easy to install. The total costs for the installation of the lime-cement columns is dependent on the numbers of installed columns, what percentage of lime and cement that has been used and the pattern in which the columns has been installed.
Vintervegetation genom ljus : om hur man med belysning kan framhäva avlövad vegetation i offentlig stadsmiljö
Use of lighting is crucial to make public urban
places available during dark hours. Landscape
architects participate in planning of lighting, but
during our education there is very little taught on
the subject. Through this study we approach the
subject of lighting by looking into lighting methods
for urban plant materials during winter.
In this thesis we look into ways to emphasize the
visible characters and experiences of urban plants
during winter season using light. Target audience
are landscape architect students and landscape
architects without knowledge of lighting. The part
of the thesis that describe basic conditions for, and
visual characters of plants can be useful to lighting
designers without knowledge in this subject.
Working methods used were the following:
? Pre-study about light and lighting techniques
through literature and dialogues.
? Compiling important visual winter plant
characters through photography and literature.
? Outdoor light experiments with plants.
Produktutveckling av klämskydd
Abstrakt
Klämning mellan dörrblad och dörrkarm är en frekvent förekommande olyckstyp som
drabbar såväl barn som vuxna i alla åldrar. I genomsnitt drabbas var fjärde
svensk någon gång under sin livstid av så pass allvarliga skador till följd av
klämning i dörr, att sjukhusvård krävs. Som regel är det handens fingrar som
skadas.
På marknaden finns ett stort utbud av tekniska lösningar som i någon mån syftar
till att förhindra klämskador i kontakt med dörrar. Dock är de flesta av dessa
lösningar utformade för dörrens gångjärnssida. För dörrbladets låssida
existerar inget klämskydd som kan göra anspråk på att vara heltäckande.
Möjligheter till reduktion av ljud från kuggväxel i markvibrator
Bakgrunden till projektet är ett examensarbete initierat av Metso Dynapac.
Företaget tillverkar maskiner för utläggning och packning av beläggnings-
och fyllnadsmaterial, t.ex. vid asfaltering. En av de maskiner som företaget
tillverkar är en markvibrator, vilken har problem med buller. En ingående
komponent i maskinen består av en kuggväxel. Kuggväxeln bedöms av företaget
vara en av källorna till buller, vilket fastställts genom mätningar.
Pga.
Anaerob psykrofil behandling av hushållsavloppsvatten i UASB : Utvärdering av kapaciteten hos en två-stegs UASB-reaktor för behandling av hushållsavloppsvatten
Hammarby Sjöstad is a new district in southern Stockholm. A main objective with the Sjöstad project was to halve the environmental impact compared to other construction work. The environmental goals involve a halved water consumption rate, a local treatment of storm water and trials aiming to extract nutrients from the waste water. Sjöstadsverket is an experimental treatment plant used for testing new treatment processes for domestic waste water from Hammarby Sjöstad. The results are to be compared with the conventional process used at Henrikdals treatment plant today.
Opportunities for improved environmental sustainability of a wine producer in South Africa : natural resource management and climate change adaptation and mitigation
South Africa has been among the top ten wine producing countries for at least 20 years. Even though the land under grapevines is decreasing globally it is still increasing in Africa. The awareness of environment has strengthen the last years and South African producers experience a high demand of environmentally friendly produced wine, especially from the European market. This demand was the driving force behind the development of the world unique sustainability certification, Integrated Production of Wine (IPW), which is inscribed in the South African legislation. What makes this certification unique is that consumers can trace their product all the way back to the farming practices owing to the identity number specified on the IPW Integrity & Sustainability seal on certified products.
Utfackningsvägg av lättbetongblock i passivhus
AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.