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3162 Uppsatser om Non-chemical control - Sida 1 av 211
Åkertistel : biologi och icke-kemisk bekämpning
A growing problem in Swedish herbicide free agriculture, the Canadian thistle has been the object of several new trials, seeking methods for non-chemical weed control. The new trials have mainly confirmed earlier experiences; that the most successful methods of control are springtime ploughing, repeated cutting and competition from a stout crop. Row hoeing has also been proven effective. As opposed to earlier recommendations, half season fallow has shown to be a risky and often ineffective method of control. Trials regarding biological methods have shown that above others thistle rust (Puccinia punctiformis) may have the potential of controlling Canadian thistle the future.
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Optimering av den kemiska reningen vid Fläskebo deponi
Landfill leachate contains a variety of contaminants and is created when rainwater percolates the landfill. For landfill management the leachate is the main issue that can cause problems to the environment. At the landfill of Fläskebo, Renova AB treats the leachate in a local treatment plant. The treatment consists of a chemical treatment step with chemical precipitation, flocculation, sedimentation and filtration, and a final step with a carbon and peat filter. Renova has to ensure that the condition of the leachate reaches the regulation set for the landfill before it is released to the recipient.
Enkla kemiska processer inom förskolan : En kvalitativ intervjustudie om förskollärares uppfattningar och tankar om läroplansmålet enkla kemiska processer
The aim of this study was to investigate preschool teacher?s perceptions about the curriculum goal concerning simple chemical processes. The result was based on narratives received by a qualitative study and semi-structured interviews of six preschool teachers. The results of the study showed that preschool teachers perceive that they actually are working in a relatively small scale with simple chemical processes and they do not really know what simple chemical processes are, and do not feel very familiar with the subject. Water, dough, mud, paint and baking were the most common activities that were used when working towards the curricular goal. However, it was never explained to the children that it was simple chemical processes they were working with during the activities, neither was it discussed among colleagues because of the uncertainty about the concept.
Utfasning av farliga kemikalier - Vid Banverket och Vägverket
Large quantities of chemicals are used in all areas of society. The chemicals can be toxic and dangerous for the environment if used incorrectly. To protect people and the environment from dangerous chemicals, a good control of them and an active work to phase out hazardous substances in all areas where chemicals are present, are needed. Banverket and Vägverket handle in production a wide range of chemical products. Many of the products are dangerous to the environment, for those who work with them and to others who may come into contact with them.
Optimering av blekeriet i CTMP-linjen vid Rottneros Bruk
At Rottneros pulp mill mechanical pulp is bleached with hydrogen peroxide. The changes of bleaching chemicals that are used for different grades are taken from bleaching tables; however these tables are old and need to be updated. The purpose of this thesis was to be the basis of new documentation.In this thesis three pulps where studied with the aim to find the optimal bleaching chemical changes (total NaOH/VP-quote) for each pulp. The pulps were taken from the filter before the bleaching tower and the pulps were bleached in the lab. The most important pulp property in this study was the brightness and how that was influenced by the chemical dosages.
Biological control of powdery mildew in greenhouse produced cucumber : an evaluation of two microbiological control agents
Powdery mildew is a serious problem in both field and greenhouse cucumber production and
can cause serious infection and radically reduced yields. Today, powdery mildew is the main
disease in greenhouse produced cucumber.
Disease control should preferably be both efficient and environmentally friendly, which is not
easy to achieve at all times. Alternatives to chemical control of powdery mildews are biological
control, physical control, non-fungicide control and cultivation of resistant or tolerant varieties.
Biological control can be described as the suppression of damaging activities inflicted
of a harmful organism by one or more other organisms, which are called antagonists or natural
enemies. In Sweden, there are currently no registered biological control products available
to control cucumber powdery mildew.
The aim of this study was to investigate the effect of two biological control products in order
to evaluate their ability to prevent or reduce powdery mildew infection to an acceptable level
in greenhouse produced cucumber. In the experiments, different application regimes were also
studied.
Utveckling av modellbaserad reglering i kommersiella styrsystem
In industrial control systems PID-control remains the prevalent strategy, also for processes that would benefit from model based control. The purpose of this thesis is to evaluate whether model based control can be readily implemented in an industrial control system. To this end a simulated surge tank with a simulated industrial control system is studied. For evaluation two scenarios with specified objectives are selected.Following a review of LQR and versions of MPC, Predictive Functional Control (PFC) is considered the most suitable for implementation. PFC is a form of MPC developed with industrial applications in mind and therefore has several advantages for implementation in an industrial control system.
Avlivning av häst : en enkätstudie
Today there are various methods to use when euthanizing horses. Earlier the use of free or captive bullet was the most common method, but in recent decades this has changed and chemical euthanasia is now considered the most common method. The chemical euthanasia has in Sweden been dominated by the use of barbiturates. Somulose® entered the market in the beginning of the 90?s as an alternative to previous chemical euthanasia.
Samverkande, motverkande eller kompletterande? : En uppsats om relationer mellan styrsystem
Title: Co-operative, prevent or complement? - An essay on the relationships between control systems. Authors: Kim Eriksson and Victoria KarlssonPurpose: The essay aims to describe the relations between control systems and how they related to each other, based on an operationalization of the control systems. Research question: What are the control systems relations to each other? With regards whether control systems co-operative, prevents and/or complement each other.Theoretical framework: The essays theoretical framework is based on Malmi and Browns (2008) description of five different control systems and control mechanisms associated with each control system. Research methodology: The method was based on three different data collection methods. These methods were observations, documentation, and semi-structured interviews.Conclusions: It is concluded that the control systems has comprehensive relations. Control systems have more, than one, relation to each other..
Uppgradering av biogas i systemperspektiv med avseende på miljöpåverkan och kostnader
Swedish biogas is currently produced mainly by anaerobic digestion of sewage sludgeat sewage treatment plants, landfills and anaerobic digestion of household or industrialwaste. Also cattle ma-nure from farms can be used to produce biogas. Upgradingbiogas represents an increase in methane concentration from about 65 % to about 97%. In addition, particles and contaminants must be sepa-rated from the upgradedbiogas. There are various methods for upgrading and this report compares sixdifferent methods with respect to environment and economy: water scrubber,Biosling, cryo technology, chemical absorption, Pressure Swing Adsorption (PSA) andmembrane separation.According to the used ORWARE model, chemical adsorption with amine has the leastenvironmen-tal impact (methane emissions) and the lowest costs.
KRAV OCH MÖJLIGHETER FÖR STYRNING AV VATTENFALLS VATTENKRAFTSTATIONER
The secondary control must be part of the production plan, since the capacity will bedeployed in advance, just as the primary control. The activation of the new frequencycontrol should be preformed in Vattenfall's operations centers (DC) to minimizecommunication delay. Vattenfall needs to work towards a more holistic optimizationsystem. The main issue for Vattenfall Generation is not how we produce but ratherwhen, which is done with creation of bids. This is where there is the mostopportunity for improvement.
Effekten av syskonplacering på Health Locus of Control : En studie om syskonplacering och kön kan relateras med locus of control ur ett hälsoperspektiv
Studier har visat att det finns ett samband mellan syskonplacering och locus of control, medan andra studier inte funnit något samband. Syftet med denna studie är att undersöka relationen mellan syskonplacering, kön och locus of control ur ett hälsoperspektiv hos gymnasieelever i årskurs 3. I undersökningen deltog 147 gymnasielever ifrån fem skolor i Kronobergs län. Resultatet visade att kön och syskonplacering samvarierade med intern health locus of control (F= 3,01;p< 0,03; ES= 6,2) och att syskonplacering och kön tillsammans inte visade någon signifikant inverkan på extern health locus of control (F= 2,20;p=<0,09; ES= 4,6). Fyndet kan indikera att manliga mellanbarn i större utsträckning strävar efter en intern health locus of control än kvinnliga mellanbarn.Nyckelord: Syskonplacering, health locus of control, intern- och extern locus of control, kön..
Utveckling av styrsystem för EMC-kammare
This thesis aims to develop a control system for measuring electromagnetic compability (EMC). This has meant that a controller designed around an ATmega8 microcontroller has been manufactured and programmed. It has also meant the development of a comprehensive control software in the program MATLAB. The control system has been tested with satisfactory results and can now, monitor and control measurements of the EMC-type..
En frivillig standards kvalitetsma?ssiga pa?verkan pa? redovisning av varuma?rken : ISO 10668
Title: Co-operative, prevent or complement? - An essay on the relationships between control systems. Authors: Kim Eriksson and Victoria KarlssonPurpose: The essay aims to describe the relations between control systems and how they related to each other, based on an operationalization of the control systems. Research question: What are the control systems relations to each other? With regards whether control systems co-operative, prevents and/or complement each other.Theoretical framework: The essays theoretical framework is based on Malmi and Browns (2008) description of five different control systems and control mechanisms associated with each control system. Research methodology: The method was based on three different data collection methods. These methods were observations, documentation, and semi-structured interviews.Conclusions: It is concluded that the control systems has comprehensive relations. Control systems have more, than one, relation to each other..
"Den som är satt i skuld är icke fri" : En studie om de svenska elnätsföretagens kapitalstrukturer
Title: Co-operative, prevent or complement? - An essay on the relationships between control systems. Authors: Kim Eriksson and Victoria KarlssonPurpose: The essay aims to describe the relations between control systems and how they related to each other, based on an operationalization of the control systems. Research question: What are the control systems relations to each other? With regards whether control systems co-operative, prevents and/or complement each other.Theoretical framework: The essays theoretical framework is based on Malmi and Browns (2008) description of five different control systems and control mechanisms associated with each control system. Research methodology: The method was based on three different data collection methods. These methods were observations, documentation, and semi-structured interviews.Conclusions: It is concluded that the control systems has comprehensive relations. Control systems have more, than one, relation to each other..