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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Evaluation of microbiological and physico-chemical quality of water from aquifers in the North West Province, South Africa

Carstens, Alewyn Johannes January 2013 (has links)
Contamination of groundwater that is suitable for drinking is of growing concern as the water supply of South Africa is becomingincreasingly limited. This is especially the case in the North West province, with its semi – arid climate and variable rainfall patterns. The aim of the study was to evaluate the microbiological and physico – chemical qualities of groundwater obtained from selected DWA (Department of Water Affairs) monitoring boreholes in the Mooi River and Harts River catchment areas. Physico -chemical parameters included temperature, pH, electrical conductivity (EC), salinity, total dissolved solids (TDS), sulphate and nitrate concentrations. Physical parameters were measured using a calibrated submerge-able multimeter and chemical parameters using specialised kits and a spectrophotometer. Microbiological parameters included heterotrophic plate counts and total and faecal coliform enumeration. Membrane filtration and culture based methods were followed for enumeration of bacteria. During the identification procedures multiplex PCR for E. coli identification and 16S rRNA gene sequencing for identification of heterotrophic plate count bacteria and amoeba resistant bacteria were used. For antibiotic resistance, the Kirby- Bauer (1996) disk diffusion method was used. During the warm and wet season high electrical conductivity and salinity were observed in the Trimpark (65.3 mS/m; 325 ppm), School (125.1 mS/m; 644 ppm), Warrenton (166.9 mS/m; 867 ppm) and Ganspan (83.3 mS/m; 421 ppm) boreholes. Warrenton borehole had a high sulphate level (450 mg/l) as well. High chemical oxygen demand was observed in the Blaauwbank (62 mg/l) and Warrenton (98.5 mg/l) boreholes. In the dry and cold season similar observations were made for the various boreholes. Electrical conductivity and salinity levels remained high for the Trimpark (70.1 mS/m; 427.5 ppm), School (127 mS/m; 645 ppm), Warrenton (173.3 mS/m; 896.5 ppm) and Ganspan (88.1 mS/m; 444.5 ppm) boreholes. Nitrate levels for the Trimpark (14.1 mg/l) and School (137 mg/l), as well as sulphate levels for the Warrenton (325 mg/l) borehole were also high. Total coliforms, faecal streptococci and HPC bacteria were enumerated from water samples from all boreholes, except Blaauwbank where no faecal streptococci were enumerated. Faecal coliforms were enumerated from 5 of the possible 7 boreholes during a warm and wet season (Trimpark – 42 cfu/100ml; School – 2 cfu/100ml; Cemetery – 175 cfu/100ml; Warrenton – 3.84 x 10³ cfu/100ml; Ganspan – 1.9 x 10³ cfu/100ml). Indicator bacteria (FC, TC, HPC) exceeded target water quality ranges (TWQR) for drinking water in each case. During the cold and dry sampling season, faecal coliforms were enumerated mainly from the Trimpark (11 cfu/100ml) borehole. Total coliforms, faecal streptococci and HPC bacteria were enumerated from all the boreholes, except for Blaauwbank that contained no faecal streptococci or total coliforms. Enumerated indicator bacteria levels again exceeded TWQR for domestic use. Total coliform counts for the Pad dam borehole, however, complied with TWQR for domestic use. Identified E. coli were resistant to Erythromycin, Cephalothin and Amoxicillin and susceptible to Ciprofloxacin. Escherichia coli isolated from the Mooi River catchment shared the same antibiotic resistance phenotype. The most abundant HPC bacterial genus identified was Pseudomonas spp. (7 isolates). Opportunistic pathogens isolated included Pseudomonas aeruginosa, Acinetobacter, Aeromonas, Alcaligenes, Flavobacterium, Bacillus cereus and Mycobacterium spp. Varying degrees of antibiotic resistance were observed. Generally, the same pattern between the same genera were observed. All HPC isolates were resistant to Cephalothin and Amoxicillin and a lower degree Erythromycin and Streptomycin. The most abundant amoeba resistant bacteria was identified as Pseudomonas spp. Other isolates included Alcaligenes faecalis and Ochrobactrum sp. and Achromobacter sp. All of these are opportunistic pathogens, except for Achromobacter. Resistance to more antibiotics (Streptomycin, Chloramphenicol, Cephalothin, and Amoxicillin) was observed in ARBs compared to HPC (Cephalothin, Amoxicillin) from bulk water from the same borehole. The water of all the aquifers sampled is of very poor physico - chemical or microbiological quality or both. Water may be used for irrigation or livestock watering only in the case where these boreholes comply with TWQR for said purposes. Results obtained indicate that the groundwater is faecally contaminated. Amongst the bacteria, opportunistic pathogens displaying various degrees of antibiotic resistance were frequently isolated. These results indicate health risks if untreated groundwater is consumed. Therefore groundwater needs to be treated before distribution especially if the water is for human consumption. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013.
12

Evaluation of microbiological and physico-chemical quality of water from aquifers in the North West Province, South Africa

Carstens, Alewyn Johannes January 2013 (has links)
Contamination of groundwater that is suitable for drinking is of growing concern as the water supply of South Africa is becomingincreasingly limited. This is especially the case in the North West province, with its semi – arid climate and variable rainfall patterns. The aim of the study was to evaluate the microbiological and physico – chemical qualities of groundwater obtained from selected DWA (Department of Water Affairs) monitoring boreholes in the Mooi River and Harts River catchment areas. Physico -chemical parameters included temperature, pH, electrical conductivity (EC), salinity, total dissolved solids (TDS), sulphate and nitrate concentrations. Physical parameters were measured using a calibrated submerge-able multimeter and chemical parameters using specialised kits and a spectrophotometer. Microbiological parameters included heterotrophic plate counts and total and faecal coliform enumeration. Membrane filtration and culture based methods were followed for enumeration of bacteria. During the identification procedures multiplex PCR for E. coli identification and 16S rRNA gene sequencing for identification of heterotrophic plate count bacteria and amoeba resistant bacteria were used. For antibiotic resistance, the Kirby- Bauer (1996) disk diffusion method was used. During the warm and wet season high electrical conductivity and salinity were observed in the Trimpark (65.3 mS/m; 325 ppm), School (125.1 mS/m; 644 ppm), Warrenton (166.9 mS/m; 867 ppm) and Ganspan (83.3 mS/m; 421 ppm) boreholes. Warrenton borehole had a high sulphate level (450 mg/l) as well. High chemical oxygen demand was observed in the Blaauwbank (62 mg/l) and Warrenton (98.5 mg/l) boreholes. In the dry and cold season similar observations were made for the various boreholes. Electrical conductivity and salinity levels remained high for the Trimpark (70.1 mS/m; 427.5 ppm), School (127 mS/m; 645 ppm), Warrenton (173.3 mS/m; 896.5 ppm) and Ganspan (88.1 mS/m; 444.5 ppm) boreholes. Nitrate levels for the Trimpark (14.1 mg/l) and School (137 mg/l), as well as sulphate levels for the Warrenton (325 mg/l) borehole were also high. Total coliforms, faecal streptococci and HPC bacteria were enumerated from water samples from all boreholes, except Blaauwbank where no faecal streptococci were enumerated. Faecal coliforms were enumerated from 5 of the possible 7 boreholes during a warm and wet season (Trimpark – 42 cfu/100ml; School – 2 cfu/100ml; Cemetery – 175 cfu/100ml; Warrenton – 3.84 x 10³ cfu/100ml; Ganspan – 1.9 x 10³ cfu/100ml). Indicator bacteria (FC, TC, HPC) exceeded target water quality ranges (TWQR) for drinking water in each case. During the cold and dry sampling season, faecal coliforms were enumerated mainly from the Trimpark (11 cfu/100ml) borehole. Total coliforms, faecal streptococci and HPC bacteria were enumerated from all the boreholes, except for Blaauwbank that contained no faecal streptococci or total coliforms. Enumerated indicator bacteria levels again exceeded TWQR for domestic use. Total coliform counts for the Pad dam borehole, however, complied with TWQR for domestic use. Identified E. coli were resistant to Erythromycin, Cephalothin and Amoxicillin and susceptible to Ciprofloxacin. Escherichia coli isolated from the Mooi River catchment shared the same antibiotic resistance phenotype. The most abundant HPC bacterial genus identified was Pseudomonas spp. (7 isolates). Opportunistic pathogens isolated included Pseudomonas aeruginosa, Acinetobacter, Aeromonas, Alcaligenes, Flavobacterium, Bacillus cereus and Mycobacterium spp. Varying degrees of antibiotic resistance were observed. Generally, the same pattern between the same genera were observed. All HPC isolates were resistant to Cephalothin and Amoxicillin and a lower degree Erythromycin and Streptomycin. The most abundant amoeba resistant bacteria was identified as Pseudomonas spp. Other isolates included Alcaligenes faecalis and Ochrobactrum sp. and Achromobacter sp. All of these are opportunistic pathogens, except for Achromobacter. Resistance to more antibiotics (Streptomycin, Chloramphenicol, Cephalothin, and Amoxicillin) was observed in ARBs compared to HPC (Cephalothin, Amoxicillin) from bulk water from the same borehole. The water of all the aquifers sampled is of very poor physico - chemical or microbiological quality or both. Water may be used for irrigation or livestock watering only in the case where these boreholes comply with TWQR for said purposes. Results obtained indicate that the groundwater is faecally contaminated. Amongst the bacteria, opportunistic pathogens displaying various degrees of antibiotic resistance were frequently isolated. These results indicate health risks if untreated groundwater is consumed. Therefore groundwater needs to be treated before distribution especially if the water is for human consumption. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013.
13

Virtual Test Environment for Motion Capture Shoots

Redavid, Claudio January 2012 (has links)
This master thesis presents the design of an implementation of a working prototype for an augmented motion capture acting environment. Motion capture (MoCap), the recording of movements to be applied to characters or objects in computer graphics simulations, is widely used in video games, advertisement, and cinema. MoCap is realized through different techniques, where one common problem is the efficiency to capture actor’s motion performances. To capture motions without obstacles for the motion detectors, actors act blindly, without graphic references while acting. Mistakes or a poor correlation between the actors performances and the computer graphics simulation requires the scene either to be taken many times or to be corrected afterwards in time-consuming post-production. These issues slow down the production process or lead to a low quality product.We suggest that one way to limit the problem of efficiency in motion capture is to let actors perform in a virtual environment. To this end, this master thesis presents a simple prototypeenvironment with the goal to support actors’ performances to improve motion capture efficiency. The idea is to surround an actor with four screens which display the virtual environment. A Microsoft Kinect camera is utilized for motion capture. Gestures are usedto trigger interactions between the actor and the virtual environment. Furthermore, the thesis explores the applicability of open source libraries, game engines, and inexpensivegeneral purpose technology. We suggest, as indicated by demonstrated validity, that virtual environments and augmented motion capture improve the conditions for actors, thus providing more efficient motion capture shots. However, further research and quantitative measurements are needed to understand and fully evaluate the effect of the presented prototype tool.
14

3D Surround Sound Application for Game Environments

Tång, Alfred January 2014 (has links)
This report covers the creation and implementation of a 3D audio application using FMOD Ex API. The report will also cover a walkthrough of the basic principles of 3D and surround audio, examples of other uses of 3D audio, a comparison between available technologies today, both software and hardware and finally the result of the implementation of the 3D sound environment software, both server and client. The application was created to explore the use of 3D audio in immersive environments. There was no application like this available when this project was conducted. An inductive approach along with a form of rapid application development and scenario creation was used to achieve the results presented in this report. The implementation resulted in a working client and server software which is able to create a 3D sound environment. Based on a user evaluation the software proved to be quite successful. With the help of the implementation the user, or operator, can now create a sound environment for another user, or a listener. The environment is created and designed by the operator using the client side of the implementation and later played through the server side which is connected to a 4.1 speaker system. The operator can steer and add sounds from the client to an active environment and the listener can experience the change in real time. This project was conducted as a bachelor thesis in computer science at Mälardalens University in Västerås, Sweden.
15

Ekerö Trappräcke

Persson, Jonas, Tasevski, Alexander January 2014 (has links)
Detta examensarbete omfattar 15 högskolepoäng och skrivs på Mälardalens Högskola i Eskilstuna med inriktning produktdesign – industriell design. Arbetet genomfördes under vårterminen, april till juni 2014 där en grupp på två personer utvecklade ett trappräcke på Lundbergs produkter AB i Nyköping. Lundbergs tog kontakt med gruppen innan start och presenterade fyra stycken uppdrag. Uppdraget var att utveckla Ekerö räcke i metall, där målet var att få räcket monterbart i trappor och gruppen blev tilldelad en kravspecifikation på vad företaget förväntade sig utav slutprodukten. På grund av den stora säkerhetsfrågan hos ett trappräcke behövdes en analys på problemet och de krav som ställdes på produkten. Gruppen började med att undersöka hur en trappa kunde vara konstruerad för att senare kunna sätta krav på trappräckets utformning. Eftersom det finns så många komponenter på den befintliga produkten så uppstod det många problem när räcket monterades i en vinklad konstruktion. Dessa problem dokumenterades och samlades ihop i olika kategorier så att gruppen senare kunde fokusera på varje område i idégenereringen. I kravspecifikationen var ett av kraven att följa boverkets regler angående trappräckesbyggen. Efter en sammanställning av boverkets regler så hade gruppen tillräckligt med material för att göra en idégenerering. I nästa skede påbörjades idégenerering med hjälp av metoden Brain Writing. Gruppen fokuserade på varje område var för sig där en större mängd idéer blev till ett fåtal som kom att kallas koncept. Med hjälp av verktyg som Pughs matris och QFD samt företagets tankar så uteslöts vissa koncept och andra vidareutvecklades. Efter att ha utvecklat två större koncept av tretton mindre så presenterade gruppen dem för uppdragsgivaren. Mötet resulterade i en kombination av båda koncepten så kunden får möjligheten att montera efter sitt egna val. När slutkonceptet var bestämt började gruppen tillverka en prototyp i skala 1:1 med hjälp av 3d-skrivare samt trä- och metallverkstaden. När gruppen arbetade på prototypen upptäcktes en risk där ett av koncepten lätt gick sönder vid montering. Då valdes koncept 1B istället för koncept 1C. Examensarbetet resulterade i en produkt som efterliknade Ekerö räcke i metall, som dessutom har många möjligheter att anpassas efter kundens krav, önskemål och kreativitet. / <p>Detta examensarbete är konversiellt, vilket är anledningen till de censurerade bilderna.</p>
16

Assessment of the physico-chemical and microbiological quality of household water in the Vaalharts irrigation scheme, South Africa / G. O'Reilly.

O'Reilly, Guzene January 2012 (has links)
Water quality in the Vaalharts region in the Northern Cape Province, South Africa, decreased over the past few years and there was a need for the microbiological and physico-chemical assessment. This problem was identified through discussions with Vaalharts Water (Vaalharts Water User Association) in 2010 when the issue of the impact of deteriorating water quality on drinking water production was raised. It was thus important to investigate concerns of the water users association pertaining to water quality issues. The aim of this study was to assess the physico-chemical and microbiological quality of household water in the Vaalharts irrigation scheme. The main residential areas were Hartswater, Pampierstad, Jan Kempdorp and Warrenton. Faecal coliforms were detected in the raw water of all the drinking water distribution systems during 2011 and 2012. No faecal coliforms were detected in the household water during 2011. This was a very positive result, because not only did the household water comply with the SANS 241 (2011) standard (0 CFU/100ml), but the purification processes were successful by removing all the E. coli’s from the raw water. However, during March 2012 faecal coliforms were detected in the household water of Jan Kempdorp (191CFU/100ml). This could be due to point pollution and possible breakage of faecal coliforms in the distribution system. Low amounts of total coliforms were detected in the raw water of some of the drinking water distribution systems. This could be due to high amounts of other colonies (pink and purple) growing on the m-Endo agar which suppress the growth of the metallic green sheen (total coliform) colonies. The total coliform numbers complied with the SANS 241 (2011) standard of ≤10 CFU/100ml at most of the distribution systems, except for Hartswater during July 2011 (14CFU/100ml) and Warrenton during March 2012 (256 CFU/100ml). Heterotrophic plate count bacteria were very high in the household water of some of the distribution systems during 2011 and 2012 which exceeded the SANS 241 (2011) standard of ≤1000 CFU/ml. A large number of pigmented (yellow, orange, pink) and non-pigmented (white) colonies were isolated on R2A agar. This can be an indication of some failure in treatment processes. Other microbiological parameters that were tested such as faceal streptococci, Clostridia, Pseudomonas aeruginosa and fungi did not indicate any danger, but there were high levels of total anaerobic bacteria in the raw water during 2011 and 2012. A high level of anaerobic bacteria was detected in the household water of Hartswater during July 2011. Clostridia were also present in the household water of some of the distribution systems during 2011 and 2012. Sequencing results of the mdh, lacZ and uidA genes indicated that one of the isolates was identified as Enterobacter cloacae and the other isolates were E. coli. Four of the isolates were identified as Escherichia coli O104:H4. This is a pathogenic strain and raised concern. The physicochemical parameters that were measured complied with the SANS 241 (2011) standards during 2011 and 2012, but some of the parameters increased gradually from 2011 to 2012. Statistical analysis indicated that physico-chemical parameters had an influence on microbiological parameters and that deteriorating raw water may have an impact on drinking water quality. Another concern currently is that there is no SANS 241 (2011) for faecal streptococci, Clostridia, Pseudomonas aeruginosa, fungi and anaerobic bacteria. These are all opportunistic pathogenic bacteria and consuming water with high levels of these bacteria may cause health problems. This study indicated good progress in the treatment processes of the distribution systems over the two years. This may be due to the feedback given to Vaalharts Water during this study regarding the water quality of the residential areas. The physico-chemical and microbiological results of the present study indicated possible biofilm formation in the distribution systems. This may have impacts on the drinking water quality of the distribution systems. It was also evident that deteriorating raw water sources may have an impact on drinking water production. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013.
17

Assessment of the physico-chemical and microbiological quality of household water in the Vaalharts irrigation scheme, South Africa / G. O'Reilly.

O'Reilly, Guzene January 2012 (has links)
Water quality in the Vaalharts region in the Northern Cape Province, South Africa, decreased over the past few years and there was a need for the microbiological and physico-chemical assessment. This problem was identified through discussions with Vaalharts Water (Vaalharts Water User Association) in 2010 when the issue of the impact of deteriorating water quality on drinking water production was raised. It was thus important to investigate concerns of the water users association pertaining to water quality issues. The aim of this study was to assess the physico-chemical and microbiological quality of household water in the Vaalharts irrigation scheme. The main residential areas were Hartswater, Pampierstad, Jan Kempdorp and Warrenton. Faecal coliforms were detected in the raw water of all the drinking water distribution systems during 2011 and 2012. No faecal coliforms were detected in the household water during 2011. This was a very positive result, because not only did the household water comply with the SANS 241 (2011) standard (0 CFU/100ml), but the purification processes were successful by removing all the E. coli’s from the raw water. However, during March 2012 faecal coliforms were detected in the household water of Jan Kempdorp (191CFU/100ml). This could be due to point pollution and possible breakage of faecal coliforms in the distribution system. Low amounts of total coliforms were detected in the raw water of some of the drinking water distribution systems. This could be due to high amounts of other colonies (pink and purple) growing on the m-Endo agar which suppress the growth of the metallic green sheen (total coliform) colonies. The total coliform numbers complied with the SANS 241 (2011) standard of ≤10 CFU/100ml at most of the distribution systems, except for Hartswater during July 2011 (14CFU/100ml) and Warrenton during March 2012 (256 CFU/100ml). Heterotrophic plate count bacteria were very high in the household water of some of the distribution systems during 2011 and 2012 which exceeded the SANS 241 (2011) standard of ≤1000 CFU/ml. A large number of pigmented (yellow, orange, pink) and non-pigmented (white) colonies were isolated on R2A agar. This can be an indication of some failure in treatment processes. Other microbiological parameters that were tested such as faceal streptococci, Clostridia, Pseudomonas aeruginosa and fungi did not indicate any danger, but there were high levels of total anaerobic bacteria in the raw water during 2011 and 2012. A high level of anaerobic bacteria was detected in the household water of Hartswater during July 2011. Clostridia were also present in the household water of some of the distribution systems during 2011 and 2012. Sequencing results of the mdh, lacZ and uidA genes indicated that one of the isolates was identified as Enterobacter cloacae and the other isolates were E. coli. Four of the isolates were identified as Escherichia coli O104:H4. This is a pathogenic strain and raised concern. The physicochemical parameters that were measured complied with the SANS 241 (2011) standards during 2011 and 2012, but some of the parameters increased gradually from 2011 to 2012. Statistical analysis indicated that physico-chemical parameters had an influence on microbiological parameters and that deteriorating raw water may have an impact on drinking water quality. Another concern currently is that there is no SANS 241 (2011) for faecal streptococci, Clostridia, Pseudomonas aeruginosa, fungi and anaerobic bacteria. These are all opportunistic pathogenic bacteria and consuming water with high levels of these bacteria may cause health problems. This study indicated good progress in the treatment processes of the distribution systems over the two years. This may be due to the feedback given to Vaalharts Water during this study regarding the water quality of the residential areas. The physico-chemical and microbiological results of the present study indicated possible biofilm formation in the distribution systems. This may have impacts on the drinking water quality of the distribution systems. It was also evident that deteriorating raw water sources may have an impact on drinking water production. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013.
18

Actuator control using pre-calibrated force data on a quadrocopter

Lafih, Amil January 2013 (has links)
In flying robots, stability control is often very sensitive to the actuator performances, and the software module performing the controller, is usually subjected to a long and difficult tuning phase strongly dependent on the specific actuator used. The actuators are often electric motors equipped with propellers. The motor and propeller combination performs differently for every choice of components adopted, even if they are provided by the same vendor with the same part family. The project aims to develop an intelligent actuator module for flying robots composed by a BLDC motor and a propeller, which is invariant to the specific motor and propeller adopted. By gathering the force data of the four used on a quadrocopter, the force and control signal relation could be defined and stored into the program memory of the control board. A battery monitor and a Force-PWM controller was implemented such that it takes force as input and outputs the desired PWM-signal. Tests were made on a prototype of Iqarus quadrocopter and by mounting it with ropes to the floor, it was tested on the lift-off phase. The experiment showed theoretical and practical results, which concludes that the quadrocopter maintained the ability to lift right upwards without any remaining control, assuming proper weight balance of the quadrocopter. / Inom flygande robotar, är stabilitet kontrollen oerhört känsligt till styrdonets prestation, och mjukvaru modulen som utför kontrollen, är ofta förknippad med en lång och problematisk justerings fas starkt beroende av de enskilda styrdonen. Styrdonen är ofta elektriska motorer med propeller. Motor och propeller kombinationen uppträder olika för varje val av komponent, även om komponenterna är försedda från samma återförsäljare och modell. Syftet med detta projekt är att utveckla en intelligent styrdons modul för flygande robotar, omfattad av en BLDC motor och propeller, som blir oberoende av den särskilda motor och propeller kombination som används. Genom att samla kraft data för de fyra styrdonen som används på en quadrocopter, kunde relationen mellan kraft och kontroll signal bli definierad och lagrad i program minnet för kontrol kortet. En batteri monitor och en Kraft-PWM kontroller implementerades, vilket tar kraft data som ingång och skickar ut motsvarande PWM-signal som utgång. Tester var gjorda med en prototyp av Iqarus quadrocopter och genom att binda fast den med rep till golvet, testades den för upplyfts fasen. Experimenten visade teoretiska och praktiska resultat, vilket visar att quadrocoptern bevarade förmågan att lyfta rakt uppåt utan någon övrig kontroll, förutsatt ordentlig vikt balans av quadrocoptern. / <p>Hejsan,</p><p>Detta ar den nya versionen, som ska ersatta den gamla versionen som blev uppladdad 6/11-13.</p><p>Tack,</p><p></p><p>Mvh</p><p>Amil Lafih</p>
19

Monteringsstation för verktygstavlor : Konstruktion och framtagning av monteringsinstruktion / Assembling station for tool boards : Construction and production of assembly instructions

Audo, Sandra, Eriksson, Pontus January 2018 (has links)
This thesis project has been carried out with Husmuttern AB as the requestor for the job. Husmuttern AB is a company in the start-up phase which works with developing module houses which are recyclable, disassemblable and standardized. The goal for the thesis project is to design an assembly station for mobile tool boards in a Husmuttern factory. There should also be instructions for the assembly station. The tool boards are used as storage for tools, safety equipment and more. The station must be usable for people without professional experience and regardless of language knowledge and background. The research questions are: * How should the instructions be designed so that a person regardless of language background can understand them? * What are the most important factors regarding ergonomics and protection against misassembly? The method used is based on the product development process described in Produktutveckling by Ulrich, K and Eppinger, S (2012), but adapted to the current project. To obtain a complete tool board one needs to place all hooks and other storage on the board and thereafter mount the boards to legs to make it mobile. To make sure that all hooks, nuts, etc. are placed correctly, installation templates are used to show where everything needs to be placed. A fixture is used for the legs, where one stands the legs, installs the boards in the correct order and uses screws to secure them. The instructions are in the shape of a Powerpoint presentation which is displayed on TV monitors in the factory. The instructions contain pictures and video showing every step of the assembly. There are also symbols, like for example arrows, pointing out important details which need to be observed. The instructions contain no current text, the only writing is numbers, which the workers are expected to understand. The project group has carried out tests with the workers in the factory. The tests have shown that the concept works. The installation templates combined with the instructions makes it easy for the workers to understand where everything needs to be placed. The fixture for the legs has not been tested with the workers in its final form, but the concept has been tested and is working satisfactorily. / Detta examensarbete har gjorts med Husmuttern AB som uppdragsgivare. Husmuttern AB är ett företag i uppstartsfasen som utvecklar modulhus som ska vara återvinningsbara, demonterbara och standardiserade. Examensarbetet går ut på att konstruera en monteringsstation för mobila verktygstavlor till en Husmuttern-fabrik. Det ska även finnas instruktioner till stationen. Tavlorna används som förvaring för verktyg, säkerhetsattiraljer m.m. Stationen ska kunna användas av människor utan yrkeserfarenhet och oavsett språkkunskaper och bakgrund. Forskningsfrågorna är: * Hur ska instruktionerna utformas så att personer oavsett språklig bakgrund kan förstå dem? * Vilka faktorer är de mest avgörande när det gäller ergonomi och skydd mot felmontering? Metoden som använts baseras på produktutvecklingsprocessen som beskrivs i Produktutveckling av Ulrich, K och Eppinger, S (2012), men är anpassad till det aktuella projektet. För att få en färdig verktygstavla behöver man montera alla krokar och annan förvaring på tavlorna och därefter montera tavlorna på ben så att den blir mobil. För att alla krokar, muttrar m.m. ska hamna på rätt plats på tavlorna har man använt hålmallar som visar var varje del ska sitta. Till benen används en fixtur som man ställer benen i, lägger i tavlorna i rätt ordning och skruvar fast dem. Instruktionerna är i form av en powerpoint-presentation som spelas upp på tv-apparater i fabriken. Instruktionerna innehåller bilder och video som visar varje moment i monteringen. De innehåller också symboler som t.ex. pilar som ska uppmärksamma viktiga detaljer. Instruktionerna innehåller ingen löpande text, den enda skrift som finns är siffror, vilka arbetarna förväntas förstå. Projektgruppen har gjort tester med arbetare i fabriken. Testerna har visat att konceptet fungerar. Hålmallarna i kombination med instruktionerna gör att arbetarna enkelt förstår var alla delar ska monteras. Fixturen för benen har inte testats på arbetarna i sin slutgiltiga form men konceptet har testats och det fungerar tillfredsställande.
20

Implementation of data-collection tools using NetFlow for statistical analysis at the ISP level / Implementation av datainsamlingsverktyg med NetFlow på ISP-nivå för statistisk analys av datatrafik

Karlström, Daniel January 2012 (has links)
Defending against Dos- and DDoS attacks is difficult to accomplish; finding and filtering out illegitimate traffic from the legitimate flow is near impossible. Taking steps to mitigate or even block the traffic can only be done once the IP addresses of the attackers are known. This is achievable by monitoring the flows to- and from the target and identifying the attacker's IP addresses, allowing the company or their ISP to block the addresses itself by blackholing them (also known as a null route). Using the IP accounting and monitoring tool “pmacct”, this thesis aims to investigate whether or not the pmacct suite is suited for larger installations when tracking and mitigating DDoS-attacks, such at an Internet Service Provider (ISP). Potential problems are the amount of traffic that need to be analyzed and the computational power required to do it. This thesis also provide information about the pmacct suite at large. The conclusions are positive, indicating it does scale up to handle larger installations when given careful consideration and planning. / Att försvara sig mot DoS-och DDoS-attacker är svårt att åstadkomma; att hitta och filtrera ut illegitim trafik från det legitima flödet är nästan omöjligt. Att vidta åtgärder när en sådan attack upptäcks kan endast göras när IP-adresserna från angriparna är kända. Detta kan uppnås genom att man övervakar trafikflödet mellan målet för attacken och angriparna och ser vilka som sänder mest data och på så sätt identifierar angriparna.. Detta tillåter företaget eller dess ISP att blockera trafiken ifrån dessa IP-adresser genom att sända trafiken vidare till ingenstans. Detta kallas blackhole-routing eller null-routing. Genom att använda redovisnings- och övervakningsprogrammet pmacct syftar denna uppsats på att undersöka hurvida pmacct-sviten är lämpad för större installationer när det gäller att spåra och förhindra DDoS-attacker, såsom hos en Internetleverantör eller dylikt. Potentialla problem som kan uppstå är att mängden trafik som måste analyserar blir för stor och för krävande. Denna avhandling går även igenom pmacct-verktyget i sig. Slutsatserna är lovande, vilket indikerar att den har potential av att kunna hantera sådana stora miljöer med noggrann planering.

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