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1073 Uppsatser om Solar heat load - Sida 49 av 72
Diagnostiksystem i gaffeltruckar
This is a final thesis done at BT, considering one of their forklift truck models called Reflex. The first part of this report is about a preliminary investigation investigating what kind of diagnostic systems BTwants to use, and also which demands there are to meet all expectations on such system. Secondly a diagnostic system, which will show if the drive wheel is worn out, will be presented. In the preliminary investigation, two kinds of diagnostic systems were mentioned. These were Model based diagnosis and Predictive analysis.
Acceptansgränsen för solceller i lågspänningsnät : Kan den ökas?
Microproduction, also called distributed generation, is something that has become more and more popular in the electric grid. Microproduction can however lead to unacceptable performance if several units are installed in the same low voltage network. It is therefore good to know a limit where the performance of the low voltage network becomes unacceptable based on given parameters. This limit is usually called hosting capacity.In this report the hosting capacity with respect to voltage and current have been studied in three low voltage networks which are located in Falu Elnäts concession area. This has been done by simulations in a GIS-program where critical times of the grid have been simulated.
Uppvärmning med spannmål och trädbränslen :
This examination work brings up opportunities to invest in a construction for heating with grain
or pellets on farm level.
As example we have chosen Fröberga Gård which is a farm located in Östergötland outside of
Söderköping.
The farm`s residential buildings is to day heated with oil and electricity.
The result of our investigation shows that heating with grain is the best alternative, partly because
of economical issues but also because you can grow the grain on your own farm and by that you
can get better economy in your seed cultivation.
To grow 16 tonne of grain as is needed demand gives a insignificant increase of work.
Further an advantage is that no investment in machines is needed because all the machines witch
is needed already is in use on the farm.
In a situation where a new investment is needed as in the case we studied, is it often profitable to
invest in a integrated furnace. Because all the components are well adapted to each other, and
because that gives a high efficiency.
If you already own a well working furnace is it often most profitable to connect a burner to it.
It is important to know that heating with grain need more work than heating with pellets, because
the high contents of ash in grain.
Even if you choose pellets instead of grain the calculation shows good results.
Because peat is an excellent but fairly untested raw material for pelletsproduction we have
chosen to watch little more on its quality and conductions.
We discovered that peat has a high heating value which makes it possible to raise the heat value
in pellets through mix up peat and wood. Or you can make pellets with only peat and get a pellet
with high heating value. Even the calculation with peatheating shows good results..
Luftfuktighetens påverkan på konstruktion och klimat i en berghangar
Aeroseum is an aviation museum located in an old military underground hangar. The ventilation system in the hangar is designed for the military purpose of the hangar. This design includes a solution with air flowing through the space between the construction of the hangar and the rock surface. The solution is intended to avoid a buildup of inflammable gases. This design leads too high humidity levels in the hangar.
Investigation of yeast Grown in SSF Dring Biothanol Production from Lignocellusosic Material
Ethanol produced from lignocellulosic biomass has the potential to become a promisingalternative to gasoline. In this work the simultaneous saccharification and fermentation (SSF)technology was applied for ethanol production from hardwood with focus on cell growth,ethanol production and contamination.The SSF was performed at PH 5.5 and 35°C for different suspended solid concentrations(8%, 10% and 12%) of pretreated birch slurry which contained 16 % total suspended solids.Two different hexose fermenting yeast strain (Ethanol Red) and pentose fermenting yeaststrain were used.Quantifying the concentration of chemical components and metabolites in the fermentationmedium demonstrated that glucose and xylose are the major fermentable sugars in the slurry.The higher load of slurry (12%) represents a higher content of carbohydrates and potentiallyhigher end concentration of ethanol. Moreover, more lactic acid is produced with the lowerload of slurry (8 % or 10 %), presumably due to a result of a less inhibitory environment forbacterial growth. In this context, acetic acid sticks out as the most important inhibitor withconcentrations of 15.2 and 12.5 and 9.7 g/l respectively in the 12 %, 10 % and 8 % (ofsuspended solids) trials. Using pentose fermenting yeast may lead to higher ethanolproduction, lower xylose uptake and lower lactic acid formation.
Mjölkureahalten som mått på vommikrobernas kväveförsörjning och kons miljöbelastning
The aim of this literature study was to analyze how milk urea concentration is working as a measure of the nitrogen supply to rumen microbes and indicator of the environmental load. Questions included in this literature study were how to improve the dairy cattle nitrogen efficiency and what correlations there are between milk urea, nitrogen efficiency and crude protein content in the feed. Effects on the reproduction from high ration protein content are also addressed. Dairy cattle are today fed with large proportions of protein which could lead to high expenditure of feed and environmental pollutions. The nitrogen can be lost to the environment by different pathways; leaching, denitrification or by emission to the air.
Mjölkureahalten som mått på vom-mikrobernas kväveförsörjning och kons miljöbelastning
The aim of this literature study was to analyze how milk urea concentration is working as a measure of the nitrogen supply to rumen microbes and indicator of the environmental load. Questions included in this literature study were how to improve the dairy cattle nitrogen efficiency and what correlations there are between milk urea, nitrogen efficiency and crude protein content in the feed. Effects on the reproduction from high ration protein content are also addressed. Dairy cattle are today fed with large proportions of protein which could lead to high expenditure of feed and environmental pollutions. The nitrogen can be lost to the environment by different pathways; leaching, denitrification or by emission to the air.
Individers erfarenhet av icke farmakologisk behandling vid långvarig smärta : En litteraturöversikt
Aim: The aim of this study was to highlighting the experiences of individuals of non-pharmacological treatment for chronic pain.Method: The study was designed as a literature review with aim to review andcompile the articles results. This study has been based on a systematic literature search of supplementing out of an unsystematic search were 11 articles were found.Results: The participants in the studies had experienced a good effect out of non-pharmacological treatments for their pain and a improved quality of life. Based on participants´ experiences of treatment two categories occurred: body awareness and relaxation. Body awareness arose through treatments like yoga, mindfulness meditation and CBT. Relaxation occurred through treatments, like music, heat, massage and meditation.Conclusion: This study highlights how non-pharmacological treatments is experienced by individuals with chronic pain and two key areas have been identified.
Tågtrafikledare i praktiken : Informationshantering och systemanvändning vid Gävle driftledningscentral
In Sweden whenever trains or maintenance workers want access to the railway system, their requests of usage and movements are being supervised, granted and handled by train dispatchers. The profession holds a key role in making the complex railway system work in terms of efficiency, safety and delivering on-time arrivals. This master thesis, delegated by the Swedish Transport Administration, has been carried out at the Division of Human Computer Interaction at Uppsala University and at the train traffic control center in Gävle. The aim has been to map what information the train dispatchers use in order to make safety-related decisions concerning their working goals. And further to describe and analyze how the train dispatchers, visavi their tools and systems in the work domain, gather necessary information.The result indicates a complex, diverse and spread out setting of different programs, procedures and tools that make satisfactory fulfilment of efficiency, safety and punctuality in relation to the time table hard.
Utvärdering av utrustning för skörd av äpplen avsedda för färskkonsumtion
During the autumn 2009, a 15 hp degree project was accomplished. The objective of the study was to describe different equipment alternatives, suitable for fresh market apple harvest. A field study was conducted during the harvest period to evaluate the efficiency (kg / person/ hour), using the different equipment. Four different systems are described in the study; Pick-ing-bag, Picking-train, Pluk-O-Trak and the Conveyor Harvester. The information about the systems is based on interviews with growers together with previous studies.
Common misconceptions about everyday astronomy-related phenomena among students in the 9th grade
Students of all ages host a wide variety of scientifically inaccurate ideas and conceptions about everyday astronomical phenomena, such as the seasons, the moon phases, and gravity. The field of Astronomy Education Research has over the last decade experienced an accelerating growth, although the majority of studies have been conducted in the USA. In this work, the 9th grade students of a typical Swedish school were surveyed by means of a questionnaire in order to probe their conceptual understanding of several key concepts in astronomy. In the end, the number of respondents amassed to a total of 90. The results were analyzed with a constructivist approach in light of conceptual change theory and phenomenological primitives.
Våtmarker för näringsretention i Lillån : var bör de ligga och vilken effekt kan vi förvänta
Construction of wetlands in the agricultural landscape may reduce nitrogen and phosphorus
transfer to streams, thereby reducing the eutrophication of lakes and seas. The agriculturalstream Lillån, a tributary to stream Sagån, ends up in Lake Mälaren and is transporting large amounts of these plant nutrients. The aim of this study was to estimate how hypothetical wetlands of different size and location may reduce nitrogen and phosphorus load from stream Lillån. Estimated nutrient retention in several small wetlands was compared to retention in a single large wetland based on existing data from the agricultural stream and from a nearby smaller stream. Retention in the stream was suggested to decrease along with the nutrient concentration in the water.
Implementering av höghastighetsgränssnitt i 0,15 µm halvledarprocess
This study investigated the possibility of implementing three standards, Transistion Minimized Differential Signaling (TMDS) and two versions of Stub Series Terminated Logic (SSTL), for inter-chip communication in a specific manufacturing process. The two SSTL standards were implemented in one transceiver system while TMDS was implemented in a separate system. The evaluation was done with Spice simulations on schematic level with some parasitic capacitance and resistance. The idea was to investigate the possibility of implementing these standards and get an idea of eventual shortcomings. In order to create models as a basis for evaluation, simulation environments with models for circuit board and packages were created and transmitters and receivers were designed.
Rening av avloppsvatten med anaerob membranbioreaktor och omvänd osmos
This master's theses was carried out on assignment from Stockholm Vatten AB as a part of a project developing new waste water treatment techniques. The goal of the theisis has been to evaluate an anaerobic membrane bioreactor for treatment of waste water from Hammarby Sjöstad. The bioreactor has not been heated and the main interest has been to study the gas production, power consumption and the reduction of organic matter and nutrients.The system has been completed with a reverse osmosis unit and a total of four batch runs have been made with good results. The use of reverse osmosis allows nutrient in the waste water to be reintroduced into circulation as the reverse osmosis concentrate can be used as crop nutrient.The membrane unit is of VSEP ("Vibratory Shear Enhanced Processing") type and an extensive membrane test has been conducted. This so called L-test helped determine the most suitable type of membrane for the system to allow a higher ±ux and thus lower power consumption.
Energibalansberäkning
Abstrakt - As energy prices rise, energy-saving in buildings is becoming increasingly important. By applying different construction and installation technologies, to new buildings the energy consumption can be reduced effectively, compared to similar existing buildings. These technical measures are often an investment in the long term and will reduce energy costs significantly. The purpose of this report is to show how to reduce energy consumption in a small house. It is presented in this report that both building's technical saving arrangements (the sealing of a building) and an installation technical arrangement (changing from the F-system to the FTX-system) would reduce energy consumption in newly built detached houses, if compared with a similar existing house but without these technical measures. The report presents also detailed calculations showing how much energy an existing 2-storey house, built in the year 2007 in Eskilstuna, consumes and how much energy would be saved if these corrective measures were applied to a new building. It is also reported how much money would be saved each year over a 10 year period if the measures were applied. The results show that both solutions are a good investment in the reduction of energy consumption and hence the cost involved. Keywords: energy, heat energy, infiltration, FTX-system, free temperature effectively. .