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1194 Uppsatser om Nitrogen flow - Sida 9 av 80
Where has the fertilizer gone? Closing the nutrient budget for a eucalyptus fertilization experiment in southern China
An increasing demand for wood products in China has resulted in large areas invested in fast-growing tree plantations of eucalyptus. Eucalyptus plantations are often associated with an intensive management including fertilization. By understanding the effects of fertilization and where in the ecosystem nutrients are accumulated a more sustainable forest management could be achieved. In this study, a nutrient budget including all biomass and soil components was created for Eucalyptus urophylla. The examined nutrients were nitrogen, phosphorus and potassium.
Elevers förståelse av fotosyntesen och dess koppling till andra organismer
The effects of the deregulation of the electricity market 1996 in Sweden on short-term hydropower regulation are unknown. This report investigates patterns in subdaily regulation in the Ångerman River Basin during the period 1993-2011. Differences in subdaily flows and zero flow events between the periods 1993-1995 and 1996-2011 were studied by analyzing hourly data from 8 regulated and 8 unregulated locations with four subdaily flow variation indices. No correlations between the market deregulation and the regulation intensity in the Ångerman River basin were detected. The number of days natural ranges of variability were exceeded and the magnitude of subdaily variation were significantly higher at regulated locations.
Modellering av ett bränslesystem i Modelica : tillämpat på ett obemannat flygplan
Mathematical models possible to simulate are of great importance in order to make successful projects in the aircraft manufacturing industry. An aircraft fuel system is very complex, containing pipes, tanks, orifices, valves and pumps. The principal of this thesis is using the tool Easy5, which no longer is considered reliable enough in terms of development and support. This thesis tries to evaluate the Modelica language as a possible alternative to Easy5. To make this evaluation, the components concerned in the fuel library in Easy5 are implemented to the Modelica language.
Urinsorterande toaletter : rensning av stopp samt uppsamling och attityder
It is important that the current urine separating systems are evaluated to allow improvements to be made and consequently increase their future propagation. In order to increase the knowledge about urine separating systems this study was made. It included, among other things, measurements of amounts of urine as well as of the composition of urine collected at Nytorgsgatan 4 in the city of Hallsberg. The study was increased after an inquiry that also included the district of Understenshöjden in the city of Stockholm. In the inquiry, the users were asked questions about odour, cleaning of toilets and occurrence of blockages in the urine water locks etc.
Opera i Stockholm : Stadsgårdskajen
The report is about efficiency of a current production group where there is no clear production flow and there are some buffers between the operations. The efficiency is done with the help of a tool that is calledWork process of flow production which is used by Atlas Copco CTO. The most obviously results are that the lead time drops from 25 hours to 425 minutes and that the balancing loss decreases from 85 % to 8 %. The report focus on decreasing transports, decreasing buffers, more reliability in lead time and quality. And a more stimulating labour content for the workers is another result..
Mätning av abrasivflöde för vattenskärningsmaskiner
The content of the following report is the summarized result of three students
thesis at Blekinge Institute of Technology in co-operation with Water Jet
Sweden AB.
This report will give the reader a description of principles how to measure the
abrasive mass flow in a waterjet cutting system.
The work began with a visit to Water Jet Sweden AB to get a closer look at the
problem. When the analysis of the problem was done the criteria were defined in
the form of demands and desires. The main task of the criteria was to guide the
search for the solution. The work proceeded with an extensive search for
abrasive flow meters along with obtaining information about flow measurement in
general. When the search for abrasive flow meters resulted in nothing all the
efforts were concentrated on finding a principle of measurement that could cope
with the criteria.
Närsaltsdosering till luftad damm : en åtgärd för ökad TOC-reduktion hos Skoghalls Bruk luftade damm
In the process of making carton boards into Skoghall Mill, are great quantities of water being contaminated. This water has to be treated before it is possible to release into the recipient, Kattfjorden. One of the contaminations that is important to extract from the wastewater, is organic carbon (measured as TOC-total organic carbon) because microbiological breakdown can lead to the bottom becomig free of oxygen.The wastewater treatment at Skoghall Mill is done through an external wastewater treatment that is located at the factory. The biological treatment (aerated lagoon) is a 140 000 m3 water pool with surface aerator, which is give oxygen to the water. In the lagoon live microorganisms who performs the biggest part of the TOC-reduction.One problem with the lagoon is that the treatment of TOC is considerably worse during wintertime than during summertime.
Kvickrotens reaktion på klippning och konkurrens i rajgräs- och vitklöverbestånd :
Couch grass (Elymus repens (L.) Gould) is a severe weed in Sweden, and since both the use of herbicides and cultivation should be decreased, it will become increasingly problematic to control couch. The present work is meant to, by literature studies and an experiment, give some answers to the question if cutting and competition can depress the growth of couch. The experiment was carried out in the growing season 2001 at Ultuna, Uppsala, in plastic boxes. The design was three-factorial randomised complete blocks. The factors were plant combination, nitrogen level and cutting strategy.
Information ochmaterialflödesförbättrings analys
This examination work is performed at the institution of industrial economy and production at Jonkoping technical university, for JELD-WEN Door Solutions plant in Forserum.Today the focus in the company is on to reduce their inventories binding of capitals as well as inventory of products and that includes to get a good control of the supply and handling of material which is of great importance.JELD-WEN Door Solutions is one of the worlds leading producers of windows and doors and the head-office is located in Oregon, USA.A great number of wooden doors are manufactured by the company in varying of constructions, classifications and performance.The production of the plant in Forserum has a project- and customer focus manufacturing where only internal doors are produced. The overall market they are concentrated on is to different institution such as schools, hospitals etc.The purpose of this work is to investigate possibilities to improvement of material- and production control at JELD-WEN. The report will handle the master production schedule to and from the production divisions within manufacturing industry. Focus will be on the way for information- and material flows from arrival, transport within the company and further on to customers.Further a map of the flow was performed which gave a clearer picture of the connection between the flow of information- and material for the manufacturing process. On the basis of the mapping of the flow, the group discovered that the flow of material had some improvement potential.
Översvämningsrisker längs Funboån
Flooding events are no longer rare, floods occur all over the world. Accordingly, it is vital for the society and different authorities to work with flood mapping. To meet the goal of Uppsala kommun to map the risks of floods in Uppsala län, a map of the different areas around Funboån which are inside the area of risk for flooding have been developed.In the work, cross sections and the water flow have been measured. Moreover, an echo-sounding have been carried out in Funboån to map the bottom topography. From the bottom map and laser scanned data covering the study area, a terrain model was created.
Nitrogen fixation among boreal feather mosses along a clear-cut chronosequence
The Swedish boreal forests are limited by nitrogen (N) availability. While biological N2 fixation by cyanobacteria hosted by pleurocarpous feather mosses are important sources of N input to natural boreal forest ecosystems, little is known about the patterns of N2 fixation in silvicultural systems. This study investigates the biological N2 fixation rates of two boreal feather moss species (Pleurozium schreberi and Hylocomium splendens) along a chronosequence from clear-cut to mature forest, as well as the vegetation characteristics along the chronosequence. Measurements and samples were collected from 32 forest sites that were classified into four age classes (clear-cut, pre-commercially thinned, thinned and mature forest). The sites were located near the city of Arvidsjaur in northern Sweden.
Del projekt inom ClampCal - Utvärdering av mätmetoder för temperatur, viskositet och densitet samt röregenskaper
The dissertation were performed on SP, Technical Institute of Sweden.
The dissertation were carried out on the measurement technical department, this dissertation is a part of a bigger project, project ClampCal.
One of SP?s returning assignments are flow-measurement. When flow-measurement is performed, the flow has to be stopped so that a meter can be installed in the pipes where measurement is going to take place. At every stop there is time delay in the flow which causes the customers to loose money. This is why SP wanted to find a better solution so that measurement can be done without any stops in the flow.
Usage of a so-called Clamp-on meter was considered, but since the measurement uncertainty is too large it takes some investigation on the parts where the largest uncertainties occur and thus find a solution that can diminish the uncertainty as much as possible.
The parts that were considered to have an opportunity to reduce measurement uncertainties were the fluid temperature, its characteristics and the pipe geometry and its characteristics.
For the fluid temperature a Pt100-sensor with four different radii for various pipes was used.
Möjligheter att förutsäga kvävegödslingsbehov i höstvete med Yara N-tester
The Yara N-Tester is a handheld chlorophyll meter which can be used in several different
crops as an aid to determine if there is a need of complementary fertilization with nitrogen
(N) or not. If the crop requires more N the N-Tester will recommend an amount in kg per ha.
The possibility to assess the need of N depends on the strong relation that exists between
chlorophyll- and N-concentration in the leaves of plants. In the multiannual trial series
?Nitrogen to winter wheat at different soil conditions? measurements with the N-Tester was
carried out at flag leaf emergence (GS 37). In this work the result of measurements, the NTesters
ability to estimate the need of N in winter wheat, will be presented for the years
2008-2011.
Förslag till energieffektivisering och energideklarationsunderlag : Munkebergsskolan och Bredängens äldreboende i Luleå
This examination work is performed at the institution of industrial economy and production at Jonkoping technical university, for JELD-WEN Door Solutions plant in Forserum.Today the focus in the company is on to reduce their inventories binding of capitals as well as inventory of products and that includes to get a good control of the supply and handling of material which is of great importance.JELD-WEN Door Solutions is one of the worlds leading producers of windows and doors and the head-office is located in Oregon, USA.A great number of wooden doors are manufactured by the company in varying of constructions, classifications and performance.The production of the plant in Forserum has a project- and customer focus manufacturing where only internal doors are produced. The overall market they are concentrated on is to different institution such as schools, hospitals etc.The purpose of this work is to investigate possibilities to improvement of material- and production control at JELD-WEN. The report will handle the master production schedule to and from the production divisions within manufacturing industry. Focus will be on the way for information- and material flows from arrival, transport within the company and further on to customers.Further a map of the flow was performed which gave a clearer picture of the connection between the flow of information- and material for the manufacturing process. On the basis of the mapping of the flow, the group discovered that the flow of material had some improvement potential.
Design för Flow : En analys av designkriterier för användbarhet
Human Computer Interaction (HCI) handlar om att utveckla produkter med god användbarhet. Med användbarhet menas att system ska vara lätta att använda och lära. Jakob Nielsen är en av förgrundsfigurerna när det gäller riktlinjer för hur detta ska uppnås. Han har utvecklat tio kriterier som kan användas för att ett så bra system som möjligt ska kunna utvecklas.På senare år har forskare börjat se till, inte bara tekniska aspekter utan även till de känslor som användaren kan tänkas uppleva under det att denna interagerar med en webbsida. Ett flertal forskare har utvecklat teorier kring begreppet Flow.