Sökresultat:
1483 Uppsatser om Water vapour transmission - Sida 15 av 99
Utvärdering av lämpliga metoder för vattengenerering
This master thesis has been performed at the department of Machine Design at KTH, The Royal Institute of Technology. The thesis has been a part of a global development project in collaboration with Luleå University of Technology, Lund Faculty of Engineering and Stanford University. Corporate liaison and sponsor has been Immerse Global Inc. The project was also performed on sponsorship from the Product Innovation Engineering Program, PIEp. The thesis is a representation of some of the contributions made by the authors.The lack of clean drinking water is one of the key issues facing the world today.
Frystorkning Kontrollerad torkning av kulturhistorisk dräkt?
Cultural objects may become wet by deliberate water cleaning, water disaster or watersoaked for other reasons. Air drying textile objects and even other organic materials from awater wet state, involves many problems depending on the strong capillarity action of water.Damages and changes such as bleeding of dyes, stains or lines of impurities from watermovement, shrinking or stiffness can occur. Freeze-drying as an alternative drying methodhas often been used for wet archaeological and marine objects, but more seldom for historicalmaterials.This bachelor thesis addresses the issue of whether freeze-drying can be an alternative controlleddrying method for historic costumes. Costumes and related objects are often compositeobjects, consisting of multiple materials, as well as being three dimensional, all of whichwill complicate drying. The purpose of this study was to investigate whether it is possible tohandle costume objects after wet cleaning for drying by freeze-drying, and if damages due tosurface tension of water, can be avoided in this way.
RCC-Jordfelsskydd, mätmodul för övertonsanalys
The majority of all power cuts that affects individuals and communities are caused by earth faults on the power transmission lines at 10kV and 20kV level [1]. If these power cuts could be eliminated, less disturbances and interrupts would lead to large amounts of money savings.Swedish Neutral has developed such a protection system. When an earth fault occurs power is injected into the neutral point of the transformer. The RCC (Residual Current Compensation) protection calculates a compensation current exactly 180 degrees out of phase to the fault current. Doing this, the voltage at the fault location becomes very close to zero, without affecting the power transmission.The protection system can only compensate automatically for the fundamental frequency (50Hz), and manually for the 3rd, 5th, 7th and 9th harmonics.
Dagvattendammars reningseffekt : påverkande faktorer och metodik för statistisk modellering
Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined.
Aggregatstabilitet, jordbearbetning och fosforförluster i ett typområde på jordbruksmark :
Large amounts of phosphorus (P) are lost from the arable land due to water erosion. Both phosphorus attached to particles and dissolved phosphorus (mainly phosphate) are transported away with drainage-water and surface runoff. Good soil structure is important in minimizing these losses.
In this study, soils from 50 fields were analysed with respect to aggregate stability as measured by dispersion of clay together with the content of total phosphorus (TotP), particulate phosphorus (PP) and phosphate phosphorus (PO4P) in the water phase. All soils were clay soils with clay content varying between 21 and 54%.
Undersökning av miljöstatusen i Gothemsån / Dalhem i anslutning till utsläpp av lakvatten från sopdeponi i Roma 2010
In October 2010 it was discovered that leach water had been released from a waste deposit directly into a ditch during a period from March until October 2010. The river Dalhemsån runs close to the waste deposit, just about 10 meters from the ditch. By studying the benthic fauna it was discovered that the environmental status of Dalhemsån is bad in this part of the river, but the discharges of leachate from the waste deposit does not seem to have deteriorated the water further since May 2010..
Kvantifiering av föroreningstillskott från dagvatten inom skyddsområdet för Göta Älv : en simuleringsstudie med modellen SEWSYS
The river Göta Älv reaches between Vänern and Gothenburg and is the main raw water source for Gothenburg that supplies about 700 000 people with water. To protect and maintain a high water quality, continuously samples and water analyses are made throughout the river. In 1998 a protection area was founded between surte and Lärjeholm where the raw water intake is. This was made to increase the awareness of the importance to protect the water. However, there is a lot of contribution of untreated stormwater to Göta Älv within the protection area.Göteborg Water and Sewage Works commissioned this thesis where two areas, Tagene industrial area and Kärra residential area, with untreated stormwater outlets within the protection area are studied.
Bäddodling av matpotatis :
This study investigated potato growing in beds as an alternative to conventional ridges.It was based on results from field trials on bed-grown potatoes carried out by Halland Rural Economy and Agricultural Society in 2007, studies of literature and interviews with farmers with experience of bed growing of potatoes.
Due to their shallow root system, potatoes are one of the most drought-sensitive crops. Potatoes are often grown on sandy soils with poor water-holding capacity. Factors such as total yield, tuber size distribution and quality defects are negatively affected when water becomes insufficient. Wide beds have a more flat top which leads to more uniform water infiltration. Further on, beds have lower soil surface area due to its shape, and therefore, retain water more efficient.
In the field trials, which were carried out at the Stjärnarp Estate near Halmstad, potatoes were grown in beds alongside a conventional ridge-grown crop.
Analys av vattenkvalitet i ett kommunalt badhus
Bath has been a part of human history for a long time. Today bathing/swimming inmunicipal pools is for people of all ages and it is possible to take swimming courses,exercise or enjoy recreation. The municipal indoor pool of Hogdalen in Sweden wasbuild in the sixties and has had problems with high levels of heterotrophic bacteria. Thefacility has two larger pools, one adventure park for young kids, two smaller bath tubsand a jacuzzi. To improve water quality UV light and coal filter were installed inOctober 2009 to the already existing purification system.
Fosforavskiljning i reaktiva filter vid småskalig avloppsrening
An excessive input of nutrients to lakes and other water bodies has created a problem with eutrophication in Sweden. Untreated, or partially treated, domestic sewage is a major source for discharge of phosphorus (P), which is the nutrient most frequently responsible for eutrophication of most fresh waters and the Baltic Sea. The waste water can be cleaned by filter materials, which have a high P-retention ability and which after saturation may be used as fertilizers. Four potentially suitable filter materials were tested in batch- and column experiments in this study. In the batch experiments, the following materials were shaken with waste water in time series ranging from 5 seconds to 60 minutes: coarse (1-4 mm) and fine (0-2 mm) Polonite® (heated bedrock from Poland); Filtralite® (light expanded clay aggregates with limestone added before burning); water cooled blast furnace slag (BF-slag) and BF-slag mixed with 10% burned limestone.
Analys av dricksvattenrening med metoderna Mikrobiologisk riskanalys (MRA) och God desinfeksjonspraksis (GDP)
Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.
Q-plats : Eett nytt arbetssätt för kontrollmätning på Scania
Metoder och system för mätteknik får en allt större betydelse för moderna tillverkningsföretag. Allt fler företag har insett det strategiska värdet av en förbättrad kvalitetsuppföljning för att minimera kostnader på grund av kvalitetsbrist. Syftet med denna rapport är att ta fram en strategi för standardisering av kontrollmätningen vid den nya typ av mätplats, en Q-plats, som ställts upp inom avdelning DXMH vid Scania Transmission. Q-platsen ger möjligheter för operatörerna att i större grad själva genomföra kontrollmätningen i närheten av produktionslinjen. I rapporten analyseras först Q-platsens funktion utifrån en studie av Scania Transmission DX, dessutom redovisas fallstudier på andra avdelningar inom Scania och vid andra tillverkningsföretag.
Rekursiv greyboxidentifiering av drivsystem i industrirobot.
In modern industrial robots the components in the transmission contain nonlinearities. These nonlinearities need to be to estimated either for better control or to use the parameters for diagnosis of the system. There is a lot of work done within system identification and mainly within the field of iterative parameter estimation.This thesis considers recursive grey-box identification for a nonlinear model of the transmission in an industrial robot. The nonlinearities that are identified are friction, spring stiffnes, hysteresis and backlash. These nonlinearities are a part of the models that are presented in this thesis.
Identifiering av fosfatfosfors käll- och flödesfördelning i ett litet jordbruksområde
Eutrophication of lakes and streams are nowadays a well known environmental problem and implies an enrichment of the nutrients phosphorus (P) and nitrogen (N). Phosphorus is considered to be the most important component for the growth of aquatic plants and leads in too large quantities to an intensification of growth. Phosphate (PO4) is the fraction of phosphorus that can easiest be taken up by plants and thus have the greatest impact on eutrophication. Increased plant growth in lakes and unfavorable conditions for aquatic animals are two examples of negative consequences. A significant portion of the increased nutrient supply to nearby water can be derived to phosphate leaching from agricultural areas, where private sewers and agriculture is two main sources.
Sjuksköterskors erfarenhet av att vårda patienter med självskadebeteende
The Swedish industrial society has left several areas with contaminated soil and water which today is of danger for the environment and human health. One of these areas with contaminated soil and water is the region where the former Glava glassworks operated during 1859 to 1939. The main object in this study has been to study the responsibility for the contaminations according to the Environmental Code. The method used is a qualitative content analysis of relevant literature to answer the following questions:What types of contaminations can be found in the area of Glava glasswork and what health issues can these cause?What kind of activity has been conducted in the area that have caused the contaminations in soil and water?According to law, what are the responsibilities for the contaminations in soil and water at Glava glassworks?The contamination in the region has been confirmed to originate from the glasswork due to the environmental engineering survey made in the area in 2009.