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1583 Uppsatser om Temperature efficiency - Sida 12 av 106

Olika naturliga kvävekällors inverkan på värmeutvecklingen i varmbänkar

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Trädgårdens hantverk och design, 15 hp, 2015.

Effektiviseringspotential inom industrisektorn : Energibesparing vid frekvensstyrning av centrifugalpumpar ? en fallstudie

The project was performed at SiemensIndustry Drive Technologies with theobjective to provide actual values forthe energy savings potential withinSiemens scope of practice.In Sweden the electrical drives standfor about 30 % of the total electricityconsumption and about 60 % of theelectricity consumption within theindustry. During the pre-study phaseelectrical drives with pump applicationswere identified as large energy users.Because of this a case study at one ofSiemens customers, Stora Enso Fors wasperformed. The system that was evaluatedduring the case study was a throttledsystem with a centrifugal pump forpumping pulp.The results yielded that a saving ofover 50 % could be achieved by replacingthe throttle valve with a variable speeddrive, a frequency converter. Thepayback period was two years and twomonths and the present value for thetotal life cycle cost of the variablespeed system was 662.566 SEK lower thanfor the throttled system. As aconsequence, Stora Enso Fors is advisedto invest in a frequency converter forregulation of the system.The general conclusion is that a focuson system efficiency is the mostimportant factor in energy efficiencyprojects and that the system regulationmethod has a large impact on the overallsystem losses and hence its efficiency.Energy efficiency potential forthrottled systems with centrifugal pumpsis large and significant economicalsavings can be made through investmentswith short payback time..

Konvertering från luft till vätskekylning av elektronik

A Swedish electronics company wants to make the cooling of one of their electronic components more efficient. They propose that a retrofit liquid cooler is the way to achieve this goal. The current air cooling has high energy cost due to the high amount of power needed to power fans and heat exchangers. Using high volumes of air for cooling also leads to noise pollution. The conversion from air to liquid cooling would possibly make the operation of the electronics more cost efficient and less noisy.The purpose of this project is to theoretically evaluate different concepts of drawing the heat generated by the electronic component in to a fluid, using numerical calculations in Matlab and FEM simulations in ANSYS.

Restspänningar i arc-förångade (Ti(1-x)Al(x))N ytskikt

This report is the written documentation of a project work carried out at the Division of Engineering Materials at Luleå University of Technology in cooperation with Seco Tools AB. The project deals with the analysis of residual stresses in Ti-Al-N thin film grown on WC/Co cutting inserts. The composition of Al varied from 0% up to 75%. Increasing the Al content in the Ti(1-x)Alx N compound improves the compressive residual stresses even after annealing of the material. The experiments have been performed in a high temperature x-ray diffractometer (HTXRD) where the interplanar atomic spacing was determined in-situ and subsequent converted into stresses.

Stopover duration and field site selection by whooper swan (Cygnus cygnus) at Lake Tysslingen, Sweden

The aim of this study was to increase the knowledge about whooper swan (Cygnus cygnus) ecology to enhance the ability to predict and also to prevent the crop damage they cause. The largest proportion of damage in Sweden has been reported at stopover sites during spring migration in February, March and April. Therefore, this study focused on an important stopover site, Lake Tysslingen, situated in south-central Sweden. Specifically, the relation between the duration and period migrating swans stage at the stopover site and mean temperature (measured at three different weather stations) for the years 2001-2010 was studied. Furthermore, the swans´ selection for certain fields in relation to field type, distance to roosting site, a supplemental feeding site and forest edge within agricultural land surrounding the lake was analyzed.

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.

Gröna värden i Lidingö och Lomma : inventering av upplevelsekvaliteter i grönområden som metodi kommunal planering

The aim of this study was to increase the knowledge about whooper swan (Cygnus cygnus) ecology to enhance the ability to predict and also to prevent the crop damage they cause. The largest proportion of damage in Sweden has been reported at stopover sites during spring migration in February, March and April. Therefore, this study focused on an important stopover site, Lake Tysslingen, situated in south-central Sweden. Specifically, the relation between the duration and period migrating swans stage at the stopover site and mean temperature (measured at three different weather stations) for the years 2001-2010 was studied. Furthermore, the swans´ selection for certain fields in relation to field type, distance to roosting site, a supplemental feeding site and forest edge within agricultural land surrounding the lake was analyzed.

Effektivitet i grundskolan - en studie om Leans applicerbarhet på processen utvecklingssamtal

Efficiency has become an important objective for many providers of welfare services. Among Swedish schools, both private and public, increased administrative demands seemingly influence operations, and affect teachers negatively through perceived stress. Simultaneously, Swedish students scored an all-time low in the latest PISA survey, and are now performing below the OECD-average in science, mathematics and reading. A central administrative task in the Swedish elementary school is the parent-teacher conference, which is an important activity in supporting the development of the student's knowledge and social skills. Lean is a well-established operations framework, which has proven successful in order to improve process efficiency.

Detection of mutations in dihydropteroate synthase (dhps) and dihydrofolate reductase (dhfr) in Plasmodium falciparum in eastern Sudan

ABSTRACT: Commercial swab transport systems are used for collection and transporting of fecal and other microbiological samples. This system must maintain viability and contribute to survival of microorganisms during transport to the laboratory. Four swab transport systems have been compared, eSwab, ?- Transwab and fecalSwab, all three with flocked swabs, and Copan Venturi Transystem with rayon swabs. The study followed the recommendations from the Clinical Laboratory Standard Institute; document M40-A for recovery of Samonella, Shigella, Yersinia and Neisseria gonorrhoeae after storage for 0, 6, 24, 48 and 72 h at room- (22-25°C) and refrigerated (2-8ºC) temperature.

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.

Ideella organisationer- En arena för diktatur

The purpose of this research was to examine the current field of management in non-profit organizations, mainly focusing on managerial approaches, but also the impact of organizational size on the shaping of governance. Non-profits are widely discussed in contemporary research, particularly due to the increasing external pressure on voluntary organization to professionalize the way they work in line with standards in the private sector. Due to this our thesis aims to investigate whether professional, bureaucratic approaches are useful when governing a non-profit organization, or if social structures are enough to ensure goal congruence and efficiency. To conduct this research qualitative interviews were carried out and a case- study was made, using the Swedish Karate Federation as object of study. Results show that formal and more professional structures are useable to achieve efficiency and prevent inertia within the organization.

Comparison of four transport systems for enetric pathogens

ABSTRACT: Commercial swab transport systems are used for collection and transporting of fecal and other microbiological samples. This system must maintain viability and contribute to survival of microorganisms during transport to the laboratory. Four swab transport systems have been compared, eSwab, ?- Transwab and fecalSwab, all three with flocked swabs, and Copan Venturi Transystem with rayon swabs. The study followed the recommendations from the Clinical Laboratory Standard Institute; document M40-A for recovery of Samonella, Shigella, Yersinia and Neisseria gonorrhoeae after storage for 0, 6, 24, 48 and 72 h at room- (22-25°C) and refrigerated (2-8ºC) temperature.

Inverkan av torrsubstanshalt och temperatur på kompostens syrabildning :

Composting is a process in which organic matter is mineralized by microorganisms. In January 2005 landfilling of organic waste was prohibited in Sweden. With this prohibition composting has become an important alternative to handle the produced organic wastes. One problem with continuous small-scale composting is the production of organic acids that will inhibit a further composting process. The aim of these theses was to study what effects temperature and dry matter content had on the production of organics acids, and what effect the organic acids had on the mineralisation of the substrate as well as the stability during storage of the product.

Djupströbädd -bra för miljö och djur?

Deep litter is a system for animals kept in separate stalls, loafing and bedding in wind shelters. The litter can consist of different bedding, like straw and peat. The system is allowed to build over and to ensure optimal proportions it is necessary to add new straw regularly and to have good conditions. Important conditions are aerobic state, humidity, amount of organic substance and acceptable temperatures in the litter. The micro organisms are depending on temperature for their living conditions and to get the bottom layer in the litter to start burning.

KappAhls sociala ansvar. Hur ser det ut i verkligheten?

With the globalization, companies in the West chose to shift production to developing countries to cut down costs. This had a major impact when child labor and very poor working conditions in these factories were discovered and led many companies to take responsibility for their suppliers and the employees by adopting voluntary so-called Codes of Conduct.There is a subtle balance to enforce improvement of working conditions for employees at suppliers´ factories and to keep costs down. On the one hand, companies would like to conduct extensive audits at their suppliers to ensure code of conduct compliance and thus protect their legitimacy. On the other hand, audits are expensive so companies would like to minimize audits to keep costs down. Companies thus have to strike a delicate balance in relation to how many and what suppliers they choose to audit.

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