Sökresultat:
894 Uppsatser om Mechanical properties - Sida 33 av 60
Formulering och provning av en ny typ av sågkedjeolja
Formulation and testing of a new type of chainsaw lubricantThe company Agro Oil has come up with the idea of developing an environmentally adapted chainsaw lubricant with a new unusual base fluid. A field test with a tree-harvester shows unsatisfactory low temperature properties and high wear. In this work the viscosity, price and pour point of different combinations of the given base fluid and three other base fluids have been investigated. Desired viscosity and price are determined for different formulations. The new lubricants tested show lower pour points than almost all products on the Swedish market.A test equipment has been developed to investigate the wear.
Resurseffektivt bussprotokoll o?ver RS-485
This report describes the design and implementation of a multi-master, packet based protocol for small and tiny microcontrollers where resources are limited. The protocol was named "Tiny Controller Network" or TCN for short. The protocol is meant mainly as a control bus for automation and sensor acquisition applications but due to its flexibility can also be used for other purposes as well. It borrows some of its functionality and design ideas from the well known CAN bus and Modbus but also has a number of major differences like the use of standard hardware and time synchronisation. One of the key aspects during the design was the use of very little system resources and common on-chip hardware peripherals like a UART.
Elektronisk publicering: vetenskapliga dokument med åtkomst via webben
The aim of this master thesis is to study electronic publishing, and our main purpose is to examine different strategies of publishing such as: markup languages and page description formats. We examine in what context these strategies are used for publishing, when it comes to scholarly documents produced by Swedish universities and university colleges during the spring of 2002. We apply a sociological perspective as the theoretical framework for to identify the main purposes for scientists to publish their work. We also discuss properties belonging to the different formats: XML, HTML, PDF and PostScript. By doing a content based survey of the websites at Borås University College and at Gothenburg University, we have found that the most common form of electronic publishing, regarding scholarly documents, are lists with bibliographical information on publications and presentations of current research.
Beräkningsmodell för massbalanser för Slottshagens reningsverk
In the next few years the pollutants loading at the Slottshagen wastewater treatment plant in Norrköping is going to increase due to the reason that one of the waste water treatment plant in the district will be shut down.A survey of how these different pollutants are divided in the treatment process is therefore necessary for mapping out both the loading and treatment efficiency.This can be achieved by studying mass balances.Mass balances were carried out for the water treatment process for the mechanical/chemical,biological and the chemical stage.The mass balance studies show that the treatment efficiency was very good. However in order for the mass balances to be quite consistent and to ensure complete coverage of results and conclusions i.e. more reliable results, sludge samples should be collected and taken at different times per day and the influent rate should be investigated.In this work mass balance has been set up in order to illustrate and identify the factors that should be considered and taken care of for further estimation using mass balances in the future. Furthermore this survey results in a calculating model for the mass balances at thisplant.This calculating model is used as a tool to facilitate future calculations for mass balances for the water treatment process at Slottshagens wastewater treatment plant.Moreover it provides a basis for carrying out further estimation of the treatment process in the near future.In this project the importance of some operating parameters was also taken in consideration.This calculating model can be modified so that calculations of such operating parameters i.e. sludge loading and sludge age can be easily performed.Such information can be used further to evaluate different operation alternative in order to ensure an optimal use of the treatment process with in the plant..
Do 25 years old skid tracks restrict growth and survival? : a study on growth conditions for the planted regeneration in a rainforest rehabilitation project
The rainforests of the world are important not only to the countries in which they grow but to the world as a whole. They influence oxygen and water circulation as well as carbon sequestration which in turn affect global radiation and global warming. The forest also have great value and in Malaysia as in many other tropical countries large volumes are harvested which leaves great areas of degraded forest with little growth and biological diversity. Due to their low financial value these forests are often transformed and used for other purposes than forestry such as oil palm plantations.
The trees are often transported out of the forest using large bulldozers. They are heavy which causes compaction of the forest floor and during transport the top soil layers are moved to improve mobility.
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.
Möjligheter att utfodra överskottsmjölk till kalvar efter pastörisering
Good feeding practices are a basic aspect of good calf health. During the calf's first few months the calf is fed with purchased milk replacer or raw milk straight from the cow. On all farms, it will be a surplus of milk that may not be delivered to the dairy for various reasons. Milk that may not be supplied to the dairy includes colostrum and milk with unnormal properties, including milk from cows suffering from mastitis. This study investigated the possibility of improving the milk by pasteurization in order to secure its use as feed for calves and thereby obtain an improved calf health.
Automatic Trimmerhead
Automatic trimmerhead is an examination project for making an automatic trimmerhead for grass trimmers with the user and functionality in focus. Our perception is that a happy user is a user who can pick up his or her trimmer, use it and put it back to its place when the job is done. It should not be necessary to interrupt work and perform maintenance on the machine just to make it work as promised.The project has been made in collaboration with the company Husqvarna, which is one of the biggest actors dealing with garden machinery on the market. Together we determined the project goal, ?To invent, construct and test a brand new concept for how an automatic trimmerhead can look and function?.At this day there are several different automatic trimmerheads on the market, both semi and fully automatic.
Spam : den nya tidens onlinegissel
This thesis takes on a broader perspective of the modern age phenomenon we call spam. One of the aims of this thesis is to present and to compare the variety of methods used in the day-to-day fight against spam, as far they have evolved today, but also to present and discuss some alternative methods for suggested future use. The properties of a common e-mail spam are analyzed to show how the components that make up the structure in an e-mail can be used to classify spam. Furthermore I explain the naïve Bayesian classification methods, the signature-based method, the commonly used rule-based method and the challenge and response method and discuss these. The widespread use of blacklists is also explained and a close new variant to blacklisting, Turntide is presented and discussed.
Framsta?llningen av barn i den nya sexualbrottslagen : en inneha?llsanalys baserad pa? fo?rarbeten
The last major change occurred in 2005 when the new sexual offenses law came into force with an increased focus on children. The purpose of this study is that through a content analysis to identify and understand the construction of children in the new legislation on sexual offenses on the basis of preliminary work. Based on the purpose we came up with two questions: How are children constructed in the preparatory works to the new sexual offenses law? Are they attributed to child characteristics and responsibilities in the new legislation on sexual offenses and if so, how? In order to achieve the purpose of the study we have chosen the preparatory works to the new legislation on sexual offenses from 2005 until today. The study's empirical work has been further narrowed to the children, which means that a distinction is made in the new legislation on sexual offenses to 6 chapter 4-6 §§.
Utveckling och konstruktion av dämpare och låssystem för vågkraftverk
The division of Electricity at Uppsala University is developing a wave energy converter(WEC) consisting of a linear generator connected to a bouy at the water surfacethrough a wire cable called the connection line.During extreme conditions, the wave power plant will experience forces up to 500kN, which lead to unnecessary wear and will ultimately cause the failure of theconverter. To prevent this there is a need for a damper.The wave energy converter works at a maximum efficiency when the translator?sare centered with respect to the stator. Due to tidal movements the position of thetranslator can deviate. There for a mechanical divice that will compensate for this isneeded.This report describes the further development of an earlier project where a tidalwave compensator for a wave energy converter of Seabased AB was developed.
Gentrifieringsprocessen : Omvandlingen av nedgångna till attraktiva stadsdelar
Title: The process of gentrification ?the transformation of declined neighbourhoods into attractive ones Gentrification = ?A social process of change where people with high socioeconomic status move into neighbourhoods which traditionally has been dominated by people from the lower classes or from ethnical minorities.? (Nationalencyklopedin 2010).In many cities around the world, disinvested neighbourhoods become the place to be, where everything happens. This usually occurs when different social groups, such as bohemians, homosexuals and artists, move into a declined and disinvested neighbourhood. After a while, people from the middleclass move in to the area due to its increased attractiveness, and start to renovate their properties. This usually leads to higher rents, which force some of the original inhabitants to leave the neighbourhood.
Kartläggning och visualisering av riggkonstruktionsprocessen : Fallstudie från Scania
Mapping a process enables a greater understanding of the work, and is standard to evaluate and improve a process. This thesis is conducted at Test Bed Mechanical Design at Scania in Södertälje. Test Bed Construction is a complex process, characterized by a large amount of creative work, technical challenges and coordination between different people and different organizational functions.The aim of the thesis was to identify the Test Bed Construction Process and to develop a visual model of the workflow that also served as support for the engineers in their daily work. During the mapping process, comparisons were made with previous research in lean product development to identify process improvement.A literature review on process mapping and process visualisation resulted in a method for process mapping. The study showed that research on process visualisation is neither structured nor well defined.
Integrerad arbetsprocess mellan projektör och konstruktör, För effektiv och kvalitetssäker projektering med Tekla Structures och SAP2000
The purpose of this work is to design and construct a device able to measure the mechanical attrition of oxygen carrier particles. Those particles are used in chemical looping combustion and in the present situation there is a lack of knowledge in how the attrition process work and in which extension. To find already tested solutions trying to answering this problem a literature study wascarried out and the best solution found was the so called Grace-Davison Jet-Cup method. This method is supposed to emulate the attrition caused by a cyclone separator and its advantages are that it is possible to use small test amounts, 5-10 g, and a thirty minutes long test will be enough to acquire useable results. An device was designed based on the Jet-Cup method with some slight modifications.
Fijian chocolate ?what would it look like?A study of the Fijian food culture, to find the specific attributes that might form the future Fijian chocolate culture
The cocoa produced in Fiji is exported to industrialized countries for processing of the raw material. The Swedish organization Cocoa Bello is involved in a project to provide the Fijian cocoa farmers with knowledge as well as resources to enable local processing and to attain added value of the cocoa crop. The purpose of this study is to discover a field of application for the Fijian cocoa among the rural population, using an ethnographic design. We spent one week in Namau Settlement, Fiji, where we applied in-depth interviews and participant obser-vations in six families. We found a number of aspects affecting food choices, such as social, economical and cultural beliefs.