Sökresultat:
2536 Uppsatser om Current measuring - Sida 24 av 170
Skalkonstruktion : Med inriktning mot hållfasthet och dämpning av ljud
The sound part is mainly practical and is dependent on concepts that have been tested through measuring with a sound level meter. The design part is more theoretical and has been verified with CAD models and finite element analysis.With a sound damping hood on the compressor the sound level is reduced with up to four dB. An optimized absorbent for the compressor space gives a reduction with three dB. By using the insulation for the heat water tank as absorbent we can see a sound reduction on the lover octave bands. A reduction like this is elsewhere hard to achieve as at it requires thick absorbents.By changing the today?s insulation to the heat water tank to a form of polystyrene polymer insulation the weight from the heat pump above can be transferred to the stable heat water tank.
Analys av svårigheter med att driva flygplatsskyltar på seriekrets
Vid idrifttagning av banljussystemet på Bana 3, Arlanda flygplats, uppstod vissa driftsproblem. Problemen yttrade sig så att de regulatorer, så kallad CCR (Constant Current Regulator), som försörjer informations- och anvisningsskyltar, löste ur för framförallt överström. Det berodde på att kretsen var ovanligt oscillativ. Problemen uppstod enbart på de kretsar som hade skyltar som last. Som belysning i skyltarna används lysrör.
Miljöeffekter av alternativa system för behandling av hushållsavfall i Santiago, Chile : en jämförelse mellan deponering och förbränning med energiutvinning
This report was written by Lisa Bengtson and Hanna Paradis and describes the
degree thesis "Environmental impacts of solid waste treatment in the Metropolitan
Region, Santiago, Chile ? a comparison between current system and incineration
with energy recovery". The purpose of this thesis was to investigate if incineration
with energy recovery could be motivated through an environmental perspective as
an alternative to landfilling of solid waste in Santiago, Chile. The study was
performed with Life Cycle Analysis as a theoretical base.
In Santiago, situated in the thirteenth region of Chile, Región Metropolitana, lives
6,5 million inhabitants. The major part of the solid waste produced in the region is
landfilled on three different sanitary controlled landfills situated outside the city
center.
Styrkor och svagheter med problembaserat lärande-en metastudie
AbstractProblem-based learning (PBL) was from the beginning developed in medical school, but is today used in education in other programmes as well. Investigations about PBL have been conducted in different disciplines and there is also metastudies. In this paper, a metastudy of 8 bachelor degree papers have been conducted. The questions answered were: which methods were used to investigate PBL in primary, lower secondary and upper secondary school,which advantages were found in working according to the PBL method, which disadvantages were found in working according to the PBL method and did teachers and students views about advantages and disadvantages about PBL as a method differ and if they did, how? The results showed that mostly qualitative methods were used to investigate the PBL as a method, mostly abilities of social qualities and independence were trained in working according to PBL, a disadvantage was that working according to the PBL method was considered more resourse consuming than traditional teaching methods and teachers and students views about PBL did not differ considerably.
Bokföringsbrott i svenska mikroföretag. : Vilka faktorer påverkar brottets svårighetsgrad?
The purpose of this master thesis is to study the correlation and meaning of current ideas and practice at the public library of Gothenburg. This was done by comparing the visions and ideas expressed by the library through the library plan, with how the daily practice looks. For the theoretical framework organizational theory is used and research data was collected both from public documents and through observations. The public library of Gothenburg were chosen for the study because of it's newly renovated facilities. The idea is that these facilities make a suitable study object of the current ideas and priorities of the public Swedish library in general.The results show that the public library practice in Sweden still rests on the original public library ideas such as offering information for free and treating every user as equal.
Biogasanvändning vid Käppalaförbundets Reningsverk: ? en värdering av miljöeffekter
This thesis calculates and compares the values of improved environmental quality due to future possible investment alternatives in biogas production facilities at Käppalaförbundets Reningsverk (Käppala Sewage Treatment Works) in an attempt to determine which alternative yields the highest such value. Käppala faces three investment alternatives for the usage of biogas. The alternatives are production of vehicle fuel, district heating and thirdly, heat and power production. Estimates of the value of environmental change are calculated for each of the three investment alternatives, and these estimates are then compared. The environmental change in question is the change in discharge levels of carbon dioxide (CO2), nitrogen oxides (NOx), sulphur dioxide (SO2) and particle matter.
Den tryckta pressens framtid i en digital miljö : Med Nya Wermlands-Tidningen som exempel
The research in question examines whether a newspaper benefits from its activity on the Internet and if so - how. Today, the morning press is relatively stable, but tendencies show that there?s a decrease amongst regular readers. The extension of this may jeopardize the position of the morning newspapers in the market and several newspapers choose to publish their content on the Internet. An Internet activity is foremost about keeping the position in the market, not to make an economical profit, and to compete at the same terms with free newspapers and news sites.
Bokmärken - En historisk redogörelse med en inblick i hur de förvaras och bevaras i museala samlingar
This thesis is intended to review and create a greater understanding for the history and originsof printed scraps from late eighteenth century to the beginning of the twentieth century.A questionnaire survey was sent out to several Swedish museums, containing questionsconcerning their collections, possible exhibits, special difficulties and types of damagesconcerning scraps and their current storage. A visit to the Gothenburg city museum storagewas made to take a closer look at their scrap collection and how they were stored. Thisresearch resulted in an understanding regarding the current situation of printed scraps, whichunfortunately appears to be quite poor and inattentive. These results are presented in the firstchapter.The second chapter describes the history of printed scraps, followed by a chapter presentingrelevant printing techniques and technology. This is followed by various chapters dealing withhow the printed scrap has been used through the ages, history and development of motifs andthe album's significance.
Utvärdering av anaerob behandling av hushållsspillvatten och tekniker för efterbehandling
The continuous process of urbanization results in demands on research and development for ecological and sustainable city development. Because of this, the current systems for wastewater treatment may have to be improved. In order to evaluate new technologies for municipal wastewater treatment, a development project has been initiated for the new district Hammarby Sjöstad in Stockholm. The project is lead by the company Stockholm Water. High environmental standards have been put up for the district, as it must be twice as good as an ordinary new district.
Fukthaltsförändringar för skogsbränsle : En jämförelse av torkförloppet i grönrisskotade och brunrisskotade vältor
In 1994 a new Forestry Act was accepted in Sweden. One of the aims of the law is to raise consideration forpreservation of biodiversity. Since the new law got accepted and some time has passed, there now lie someinterest in examining whether the law has been effective towards its purpose. Methods suitable for analysishave been examined during this study. The content of this pilot study is based around five parameters whichcan be used to validate the effects of the new law.
SMED implementation vid slipoperation
The thesis has investigated how Sandvik Coromant could implement the SMED principle on one of their grinders groups and what improvements it would lead to. The aim of the thesis is to identify the current situation and investigate how their setup times would be affected by SMED. The work initiated with a literature analysis about the SMED principles and then proceeded with an analysis of the current situation where the activity was time mapped. The analysis consisted of time trials of the process that the thesis would include. The time studies revealed opportunities for structural improvements to create environment for a more structured process.
A First Effort to Visualize Knowledge of a Region? A visualization of Öresund & Shenzhen in the perspective of Knowledge Innovation Zone
We have through our theoretical framework been able to create a simplified measuring tool for a KIZ; the S-TKL. We have found that the S-TKL is possible to implement on the Öresund Region but with some flaws. Even though the Öresund Region has implemented the mindset of a KIZ, accurate statistics are in some areas hard to find. We can also through our empirical findings say that it is difficult to use the S-TKL on Shenzhen. The data we have found gives a good indication of both of the regions.
Tredimensionell sensorscanner
This report is a bachelor thesis presented at the department of Computer Science andEngineering at Chalmers University of Technology. The aim for the project is to find a simplemethod to measure and display physical quantities in a three dimensional room.The report describes a method to construct a system for measuring differentphysical quantities via sensors. The system must be built in a modular and expandable way tobe adaptable to different tasks.The system explained in the report consists of two parts;A physical scanner with moveable probes for carrying sensors and a microcontroller forcontrolling the probes and communicating with the next part.An application written in Java for storing the measured values and presenting them in a lucidperspective.It is possible to construct the scanner with different designs and circuitry, with multiplexers andflip-flops, to ensure that an unspecified number of probes can be added to the system and thatthey can be operated simultaneously.The Java application is written in a modular way, using a design pattern that separates eachindividual part of the application. It contains exceptions and interfaces that ensure a safe andexpandable application..
Pilotinstallation av fast och fjärravläst nätstationsmätning : Identifiering av för- och nackdelar med nätstationsmätning, Mälarenergi Elnät AB
Today?s electrical grid companies understand that better knowledge of and information about their grid can help realize a smart grid network. One way to gain better knowledge and information about the low voltage network is to install measuring equipment on the substation transformer´s secondary low voltage side that measures the low voltage network losses for that specific substation. By doing so, grid companies can, due to the calculation of the low voltage network losses, identify and address issues such as illegal power dissipation, unmeasured power outtakes, and unsatisfied technical documentation for the substations low voltage network.During 2012, Mälarenergi Elnät AB had a total electrical network loss (both medium and low voltage network losses included) of three to four percent of their total distributed electrical volume. Converting this energy volume into a monetary figure this accounts for a loss of around 30 million Swedish crowns.
Cassava as an additive in biomass fuel pellet production :
In this study, the effects of using fine milled cassava stems as an additive in biofuel pellet production was compared to the effects of refined starch addition. The bulk biomass fuel raw material, to which the additive was added, was a blend of spruce and pine sawdust. An experimental design in the factors cassava/starch content, moisture content and material temperature was used. Measured responses were pellet bulk density, pellet durability, amount of fines, pelletizer motor current, pellet temperature, die temperature and CV for pelletizer motor current (a measure of process stability). Each response was modeled by multiple linear regression (MLR).