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1524 Uppsatser om Sub surface flow wetlands - Sida 7 av 102
Evaluation and Comparison of Ecological Models Simulating Nitrogen Processes in Treatment Wetlands,Implemented in Modelica
Two ecological models of nitrogen processes in treatment wetlands have been evaluated and compared. These models have been implemented, simulated, and visualized in the Modelica language. The differences and similarities between the Modelica modeling environment used in this thesis and other environments or tools for ecological modeling have been evaluated. The modeling tools evaluated are PowerSim, Simile, Stella, the MathModelica Model Editor, and WEST. The evaluation and the analysis have been performed using McCall?s factors for software quality (McCall et al, 1977), a correlation analysis and the Constant Comparative Method (Glaser&Strauss, 1999).
Utveckling av heltäckande gångbord
This thesis work is a 30hp D-level assignment in design as a co-operation between MälardalenUniversity and Scania CV AB in Södertälje. The purpose was to develope a close fitted catwalk.The market has seen an increasing value for these types of applications and have the ambition to keep up with the rest of the competitors. The catwalks of todays standards shall be estetical attractive, have a non slippery surface and be costefficient.While working with this project I have spent a lot of time with the concept proposals and with the evaluation of the concepts, resulting in a final CAD model and a approximation of the cost estimate. The new catwalk fulfils all the new recommendations and rules as sharp edges, ADR, the height of the stepup and a non slippery surface with built in drainage..
Störs laxens lekvandring i en kraftverkspåverkad älvsträcka? :
The upstream spawning migration of Atlantic salmon (Salmo salar) at the confluence
area between the power-station outlet and the bypass-channel in river Umeälven (flow 430
m3s-1) was compared in 2004 and 2005, two years with different experimental flow-regimes.
In 2004 the water flow in the bypass-channel was altered during the day with increased
flows during the nights while the water flow in 2005 mainly was altered between the
weekdays and weekends. Salmon showed altered migratory behaviour in this confluence
area, assessed with telemetry (n=116) and echo-sounding, with up- or downstream responses
depending on flow-changes in both the bypass and the power station outlet. Increased
turbine flow through the power-station generally attracted salmon into the tunnel outlet area
while increased spill-flows facilitated salmon to enter the bypass. Echo-sounding in the
confluence area showed an increased swimming activity up- and downstream due to time in
the day and flow-rates through the tunnel outlet. No changes in activity could be detected
due to increasing or decreasing flow through the hydro-power facility.
Behuggning av betongytor: ett test av hantverksmetoder
During the latter half of the 18th century, when concrete started seeing general use in
modern cities, the use of different methods to give the concrete a finished surface texture
saw use. One of these was using different methods of mechanically altering the surface using
a slew of cutting and crushing techniques with mallet and chisel. This was done in order to
hide the often dull and gray look of concrete, and allude to other more expensive and
luxurious stones. The work would possibly have been done by experienced stonemasons,
using much of the same techniques and tools they would have used while working natural
stones. Or did they? This essay explores, through the use of traditional handcrafts and tools,
the claim that the working of concrete surfaces can be done with the same tools and skillset
as the working of natural stone.
Hur påverkar bävern skogens värden?
The activities of beavers in forested landscapes affect both ecological and economical values. The creation of the dynamic wetland mosaic associated to beaver activities can even improve the quality of water and have been documented as an important landscape engineer affecting the environment for many species. The local office of Sveaskog in Skinnskatteberg is responsible for the management of large areas of the forests in the County of Västmanland. In this area one of several company?s goals are to create ten new wetlands in their own forests as a part of cooperation with the Swedish bird society and Swedish wetland association.
Energieffektivisering i ett reningsverk för skogsindustriellt avloppsvatten genom förfällning av extraktivämnen
Pulp- and papermills expend vast amounts of water in order to produce pulp, paper and cardboard. Hence, they alsocreate vast amounts of waste water which has to be cleaned before it can be released into the receiving body of water. Insuch a wastewater treatment plant, tremendous amounts of energy are expended by the aeration in the biologicalcleaning process. This aeration is necessary to supply the microorganisms that shall decompose organic material withoxygen, which they need for their metabolism. The transfer of oxygen from the gas phase to the liquid phase isprimarily inhibited by surface-active substances in the waste water like resin acids or fatty acids.
Dimensioner. Mellan 2D och 3D, en undersökning av yta och innehåll
A project exploring the boundaries between 2D and 3D. What is surface and what is substance? A countinuation of previous projects where I?ve examined the journey from two dimensional paper to three dimensonal objects. This project deals with the journey from three dimensonality back into a flat two dimensional surface, and the question if something can be both 2D and 3D at the same time. I decided not to center the project around a specific item, but rather let the project itself be in focus.
Fälttest av en ny metod att med objektiva mätmetoder karaktärisera egenskaperna hos ridunderlag- en pilotstudie. :
Background
Research concerning footing and its contribution to injuries has been conducted primarily in racing Thoroughbreds. Studies in UK and Japan indicate that some specific factors could be responsible for an increase in performance-associated injuries. Researchers in Sweden have performed studies on Standardbred trotters. More research is needed to be done on equestrian sports since requirements on footing are not exactly the same in riding and trotting horses.
The lack of scientific evidence on the construction of equestrian surfaces has lead to anecdotal validation of designs.
Kartläggning och effektivisering av ljuddämparflöde
In 2013 a new emission standard for heavy trucks was introduced and hence a number of new parts was brought in to Scania CV AB. This created a need for modifications in the silencers flow. The flow is highly complex involving several suppliers, call off methods and different models of silencers. The aim for this project was to improve the existing silencers flow. The flow, from supplier to assembling, has therefore been mapped.
Kassaflödesanalyser - En undersökning av kassaflödesanalysens användning i förhållande till det tidsperspektiv som styr företagens agerande.
Purpose: The purpose of this thesis is to investigate potential associations
between usage of the cash flow statement report and time perspective in which
companies? acts and set goals.
Method: Our approach is quantitative, using empirical data summarized in a
statistical procedure. The result is thereafter analysed through the developed
analysis model from which conclusion is drawn.
Results: We have in the investigation stated that the usage of the cash flow
statement report varies depending on the time perspective in which companies?
acts.
Förstudie till våtmark i Rimbo : Design för optimal hydrologi och kväverening
The euthropthication of the Baltic Sea is a threat that is beginning to be taken seriously by the governments concerned. In Sweden, regulations concerning the allowed nitrogen (N) concentration in the effluent water from wastewater treatment plants are being tightened up. The Rimbo wastewater treatment plant has been imposed to reduce the annual mean concentration of total N in the effluent water to levels below 15 mg l-1. A more and more common way to reduce the nitrogen level in wastewater is to let the water pass through a wetland. This study investigates the possibility to build this kind of wetland at the outlet of the Rimbo wastewater treatment plant.A prestudy of the topography, soil characteristics and groundwater flow indicates that the land area in question is well suited for the construction of a wetland.
Klinisk termografi som diagnostiskt hjälpmedel vid rörelsestörning hos häst :
Thermography is the assesment of the surface temperature of the horses body and it falls into the categori of physiological imaging. Thermography allows us to portray inflammation and changes in sympathetic tone in a graphical manner.
The purpose of this study was to review thermography in equine medicine and to evaluate thermography as an aid in the diagnosis of lamness in horses.
Thermography has been helpful to identyfy sprains, stress fractures, shin splints and soft tissue, tendon, ligamentous and nerv injuries and to monitor healing processes during rehabilitation. Routine thermography may reveal inflammatory responses prior to clinical signs.
In present study thermograpy gave especially valuabel information in two cases. In one horse reduced blood flow in a. saphena due to a thrombosis were visualised and in the other horse bilateral thoracolumbal radiculopati was diagnosed.
Översvämningskartering av Vombs ängar
Vomb meadows is an area well knows for its rich bird life. During the 19:thcentury until mid 20:th century, the meadows were flooded annually in order toincrease the hay yield. The river Klingavälsån situated along the west side of themeadows, used to be a shallow river, meandering across the landscape. In the1940?s the river was straightened and made deeper.
Prestanda på luftfilter : En jämförelse mellan olika filter till bil
This reports goal is the give BSR AB more information that's useful towards their customers in marketing of their products.It involves tests of different air filters designed for cars and 3D-modelling of Opti-Flow systems. The three models thats being tested is SAAB (93SS), VAG (1.8T) and Volvo (S60). To every brand there are three different models. A orginal- , sport- and an open cone air filter (Opti-Flow).The results indicate that the open Opti-Flow filter has better performance compared to the other cased filters. The sport filters for SAAB and Volvo has better performance then the original filter.
Flyt tillsammans : Emotionell gemenskap i kooperativa spel
Studien undersöker känslomässiga reaktioner vid kooperativt spelande, vilka som är gemensamma för båda spelarna och hur de påverkas av hur svårt spelet är. Arbetet utgick från studier av spelares emotionella reaktioner på spel och teorierna om Flow. Spelet Sanctum användes i en serie tester där mätningar utfördes på två spelare med hjälp av rapportformulär, pulsmätare och hjärna-till-datorgränssnittet Emotiv EPOC. Studien fann att spelarna ibland upplevde samma känslor när de spelade tillsammans och att den ökade svårighetsgradens huvudsakliga effekt var att förändringarna i känslorna blev skarpare och större. Det tycktes huvudsakligen vara motgångar som splittrade spelarnas upplevelser.