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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

MICROFLUIDIC DISPENSERS BASED ON STRUCTURALLY PROGRAMMABLE MICROFLUIDIC SYSTEMS (sPROMs)AND THEIR APPLICATIONS FOR μTAS

PUNTAMBEKAR, ANIRUDDHA P. 31 March 2004 (has links)
No description available.
12

Thermionic Electron Emission Microscopy Studies of Barium and Scandium Oxides on Tungsten

Vaughn, Joel M. 23 September 2010 (has links)
No description available.
13

Investigation, development and testing of a low cost Solar Heat Barrow (SHB) and purifier / D.F. le Roux

Le Roux, Daniël Francois January 2003 (has links)
Many rural communities in South Africa do not have running water or electricity. The fetching and heating of water is therefore a time consuming and expensive daily ritual. The use of energy sources such as wood or coal are not readily available and cause environmental pollution. Although solar water heaters are commonly available in South Africa, they are very seldom used in rural areas. Whilst this can mostly be attributed to a high system cost, current designs also do not cater for specific rural problems such as the transporting or purification of water. A prototype model, designed with such an approach in mind, has already been constructed by TEMM International (Pty.) Ltd. The Solar Heat Barrow (SHB) was developed in the 1992 to 2003 period with the intention of combining a number of functions at low cost. Specific requirements were: low cost, a suitable design and materials for manufacture in large volume, sufficiently durable taking into account the harsh conditions of use. suitability for cases where no in-house piped water supply was available, the use of appropriate technology and the improvement of quality of life. The unit combines the absorption of solar radiation, the heating of a relatively small volume of water, the transport of the water from the point of supply and the storage of the hot water until it is used. Untreated water sources such as surface waters (streams, rivers, lakes, etc.) or unprotected open wells are the vehicles for waterborne bacterial diseases such as cholera and typhoid fevers. In the case where water is collected from these sources, the SHB has a build-in Purification Dispenser that purifies the water in the collector against waterborne bacterial diseases. Certain research questions need to be answered. They will be answered by demonstrating the SHB in two communities where no in-house piped water supply is available and by establishing the socio-economic response of the users. The research questions are as follow: What are the responses of the users concerning the SHB, in comparison to those of a control group, regarding its operation, durability, utility and satisfaction of needs? What is the daily use of hot water and the reduction in energy use and cost? To what extent will the target community purchase the SHB at the full or subsidised commercial price? Is there a business case that can be developed for the large scale production, marketing. financing and Small, Medium and Micro Enterprises (SMME) development of the SHB? It was decided to choose a community in the Valley of Thousand Hills in KwaZulu Natal as the demonstration site. The name of the community is Mabedlane. It is a remote rural area 20 km's north of Botha's Hill and is situated along the Umgeni River. The community is dependent on the river for domestic water. Most families are headed by women. The area has low levels of infrastructure, poor roads, a high unemployment rate and poor health facilities. The first survey, which was conducted before the test period started, showed a very positive response from potential users. From 112 questionnaires that were given to the people of Mabedlane, all indicated that they were interested in a product that can transport and heat water for domestic use. The socio-economic study has shown that the price per unit needs to be adapted as 85% of the people who participated in the survey indicated that they would only pay less than R100 for the product. 15% indicated that they would pay between RlOO and R200. From the second and third questionnaires it was clear that the users were satisfied with the heating performances of the SHB. The community was very interested in purchasing a SHB. They have realised that a SHB will improve their standard of living and regard it as a necessity in their day to day activities. It is apparent that people, who will benefit from a SHB most, are those who will not be able to pay the full retail price. Therefore, new business strategies have to be researched when implementing the SHB to the target market in South Africa. The idea of considering ways to sponsorlfund the SHB must also be investigated. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2004.
14

Investigation, development and testing of a low cost Solar Heat Barrow (SHB) and purifier / D.F. le Roux

Le Roux, Daniël Francois January 2003 (has links)
Many rural communities in South Africa do not have running water or electricity. The fetching and heating of water is therefore a time consuming and expensive daily ritual. The use of energy sources such as wood or coal are not readily available and cause environmental pollution. Although solar water heaters are commonly available in South Africa, they are very seldom used in rural areas. Whilst this can mostly be attributed to a high system cost, current designs also do not cater for specific rural problems such as the transporting or purification of water. A prototype model, designed with such an approach in mind, has already been constructed by TEMM International (Pty.) Ltd. The Solar Heat Barrow (SHB) was developed in the 1992 to 2003 period with the intention of combining a number of functions at low cost. Specific requirements were: low cost, a suitable design and materials for manufacture in large volume, sufficiently durable taking into account the harsh conditions of use. suitability for cases where no in-house piped water supply was available, the use of appropriate technology and the improvement of quality of life. The unit combines the absorption of solar radiation, the heating of a relatively small volume of water, the transport of the water from the point of supply and the storage of the hot water until it is used. Untreated water sources such as surface waters (streams, rivers, lakes, etc.) or unprotected open wells are the vehicles for waterborne bacterial diseases such as cholera and typhoid fevers. In the case where water is collected from these sources, the SHB has a build-in Purification Dispenser that purifies the water in the collector against waterborne bacterial diseases. Certain research questions need to be answered. They will be answered by demonstrating the SHB in two communities where no in-house piped water supply is available and by establishing the socio-economic response of the users. The research questions are as follow: What are the responses of the users concerning the SHB, in comparison to those of a control group, regarding its operation, durability, utility and satisfaction of needs? What is the daily use of hot water and the reduction in energy use and cost? To what extent will the target community purchase the SHB at the full or subsidised commercial price? Is there a business case that can be developed for the large scale production, marketing. financing and Small, Medium and Micro Enterprises (SMME) development of the SHB? It was decided to choose a community in the Valley of Thousand Hills in KwaZulu Natal as the demonstration site. The name of the community is Mabedlane. It is a remote rural area 20 km's north of Botha's Hill and is situated along the Umgeni River. The community is dependent on the river for domestic water. Most families are headed by women. The area has low levels of infrastructure, poor roads, a high unemployment rate and poor health facilities. The first survey, which was conducted before the test period started, showed a very positive response from potential users. From 112 questionnaires that were given to the people of Mabedlane, all indicated that they were interested in a product that can transport and heat water for domestic use. The socio-economic study has shown that the price per unit needs to be adapted as 85% of the people who participated in the survey indicated that they would only pay less than R100 for the product. 15% indicated that they would pay between RlOO and R200. From the second and third questionnaires it was clear that the users were satisfied with the heating performances of the SHB. The community was very interested in purchasing a SHB. They have realised that a SHB will improve their standard of living and regard it as a necessity in their day to day activities. It is apparent that people, who will benefit from a SHB most, are those who will not be able to pay the full retail price. Therefore, new business strategies have to be researched when implementing the SHB to the target market in South Africa. The idea of considering ways to sponsorlfund the SHB must also be investigated. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2004.
15

Minkastare : ett system för Försvarsmakten?

Wikström, Henrik January 2012 (has links)
Minvapnet klassas fortfarande som en viktig faktor vid strid, dock har dess utveckling i den svenska Försvarsmakten hamnat i skymundan. Denna slutsats kan man dra om man ser till vilka uppgifter och vilken utrustning som i dagsläget finns för att minera. De hjälpmedel som finns och är brukbara är ytterst begränsade. Ett system som skulle kunna vända denna trend är en minkastare, något som bland annat tas upp i, för fältarbetesfunktionen, interna utvecklingsplaner. Syftet med denna uppsats är att undersöka huruvida Försvarsmakten skulle kunna nyttja ett minkastarsystem, vad det skulle innebära för Försvarsmaktens förmåga att minera samt lyfta upp vilka kriterier ett sådant system skulle behöva leva upp till för att kunna nyttjas av svensk trupp. Huvuddelen av uppsatsen kretsar kring textanalyser av aktuella reglementen, styrdokument och utredningar. I och med den nära knytningen till Försvarsmakten används de grundläggande förmågorna som analysverktyg och som teorikoppling. Uppsatsens resultat påvisar att införandet av ett sådant system skulle utveckla arméns, och framförallt då ingenjörförbandens förmåga att minera. Dock kan den faktiska nyttan av ett sådant system ifrågasättas i dagens insatsinriktade Försvarsmakt.
16

Construction of Control system for syringe dispenser based on Printrbot 3D printer

An, Qi January 2020 (has links)
3D printers require a reliable and robust control system to provide the proper quality for printed parts. Dispenser 3D printers are widely used in various fields of scientific research. The goal of this project is to build a disperser 3D printer based on Printrbot 3D printer, design and implement the control system and software. This system was able to control the dispenser, performed the correct operation according to the instructions. The operating system was built by LabVIEW for file reading and printer control.
17

A.D.D : Autonomous Drink Dispenser / A.D.D : Autonom dryckesfördelare

Sjöberg, Mikael, Xu, Jonas January 2019 (has links)
The purpose of this report was to evaluate the feasibility of an autonomous drink dispenser where it can complement the waitstaff in their many duties. The prototype can accurately dispense a wide variety of drinks without the intervention of a human operator. The focus of the project was to pour a wide variety of drinks as accurately as possible. This can be achieved without the need for trained staff through automation. Many different components were required in order to make the prototype as consistent and safe as possible. It was discovered that so many components negatively affected the end result. The final prototype can dispense liquids from six different sources. Numerous different tests were done with the maximum deviation from the expected volume being 7.7%. This was a vast improvement on the standard deviation in alcohol content in drinks, which is 42%. The prototype can dispense up to 116 drinks per hour. / Syftet med denna rapport var att utvärdera genomförbarheten av en autonom dryckesautomat där den kunde komplettera servitören i sina många uppgifter. Prototypen kan med hög noggrannhet hälla upp en stor variation av drycker utan behovet av en mänsklig operatör.  Projektets fokus var att kunna hälla ett stort antal drycker med så hög precision som möjligt. Genom automatisering kan detta uppnås utan behov av utbildad personal. Många olika slags komponenter krävdes för att göra prototypen så konsekvent och säker som möjligt. Det visade sig att denna variation skapade problem och hade en negativ effekt på det önskade slutresultatet. Den slutliga prototypen kan hälla upp vätskor från sex olika källor. Många tester gjordes med en maximal avvikelse från den förväntade volymen på 7.7%. Detta var en stor förbättring på standardavvikelsen i alkoholhaltiga drycker, vilket är 42%. Prototypen kan hälla upp till 116 drycker per timme.
18

Autonomous Liquid Dispenser : A.L.D. / Automatisk vätskeautomat

Gan, William, Håkansson, Oliver January 2020 (has links)
Our society has become more and more digitized and futuristic in the service sector. The urge of efficiency in order to maintain a stable income and profit is increasing in various businesses. One such business is the hotel and restaurant business which heavily relies on staff members being efficient. The purpose of this report is to evaluate how automation and efficiency can be combined and integrated into this branch. The main reason being to release employees in this branch from repetitive tasks and put the focus on delivering high quality customer service instead. The main goal in this report will be on dispensing a variety of both carbonated and non-carbonated drinks using an autonomous system that strives to have the same accuracy and skill as a dispenser operated by a human. To achieve this goal an autonomous liquid dispenser consisting of two ultrasonic sensors had to be constructed. It should be able to detect when a glass needs to be filled with liquid, decrease the foam by tilting the glass and replace it to it’s original state. The system was evaluated using three different experiments, where two of them measured the accuracy of the construction. The results from the two experiments concluded that the constructed system is of high accuracy. The result from the third experiment tested the speed for one dispensation cycle and the conclusion was that improvements can be made. / Automatisering och digitalisering av olika sorters arbetsuppgifter har ökat mer och mer sedan 70-talet och fortsätter att öka. Detta för att kunna effektivisera arbetsprocesser och därmed öka lönsamheten i verksamheten. Syftet med denna rapport är att utvärdera huruvida denna effektivisering och automatisering kan tillämpas i en barmiljö. Detta för att frigöra tid från personalen från repetitiva uppgifter och därmed tillåta dem att fokusera mer på andra mer krävande arbetsuppgifter. Fokuset i denna rapport är på upphällningen av olika drycker med kolsyra och hur detta kan göras av ett autonomt system med samma precision och skicklighet som hos en människa. Detta utförs genom att tillverka en prototyp som med hjälp av en ultraljudssensor känner av att ett glas ställs på rätt plats, för att sedan vinkla glaset samtidigt som det fylls med den önskade vätskan. När glaset sedan är fyllt med önskad mängd vätska så vinklas plattformen tillbaka och uppgiften ¨ar klar.  Systemet utvärderades senare utifrån tre tester. Där två av dem testade precisionen i konstruktionen. Resultatet i dessa två tester var att precisionen i systemet är godkänd. Resultatet från det tredje testet som kollade på tiden det tar för systemet att utföra en cykel var att detta behöver arbetas vidare med och detta resultat analyseras mer i Chapter 5.
19

Survey of different mealybug species and attending ants and their management in Virginia vineyards

Chalise, Pragya 01 November 2023 (has links)
Mealybugs (Order Hemiptera: Superfamily Coccoidea) represent a persistent problem in grape-growing regions globally, with a notable increase in infestations in recent times. The current study investigates the species composition and seasonal dynamics of mealybugs in vineyards. Pseudococcus maritimus and Ferissia gilli remain the dominant species, while Pseudococcus viburni was also spotted during two separate instances and Planococcus ficus remained absent. Commercially available pheromone delta traps and adhesive bands were deployed to capture the male mealybugs, while numerically higher efficacy was observed in the adhesive band trap. Notably, the placement of adhesive band traps on the cordon and trunk revealed differential male mealybug captures, probably indicating their movement within the vines. The research also divulges into the life cycle of mealybugs and their population densities during the sampling season. The main highlight has been the lower population density of earlier nymphal stages of the first generation of mealybugs followed by the colonization of grapevines by the second-generation crawlers. Adults of second generations give rise to the overwintering stages of mealybugs. Traditionally the research also explores the species and seasonal population dynamics of ants along with mealybugs and their management in Virginia vineyards. The activity of fifteen genera of ants in the vineyard was recorded, with some of the dominant ant genera like Tetramorium, Crematogaster, and Lasius were recorded in the vineyard actively tending and defending the mealybugs and moving them around. Fruit cluster infestation was also higher in the control treatment in comparison to sugar dispenser and ant bait dispenser treatments. This comprehensive assessment of ant diversity further deepens our understanding of the intricate ecosystem within vineyards. A spray trial using three different insecticides with distinct modes of action (Buprofezin, Bifenthrin, and Spirotetramat) in two of the commercial vineyards. Preliminary results indicate that on some days after treatment, insecticides effectively controlled mealybug populations, offering a glimmer of hope to vineyard owners grappling with infestations. Mealybugs pose a significant threat to grape cultivation, and this research provides valuable insights that can help vineyard owners and grape growers develop more targeted and effective control strategies. Species identification, understanding their behavior, and exploring potential allies in the fight against mealybugs are all crucial steps toward maintaining the health and productivity of vineyards in Virginia. While challenges remain in the battle against mealybugs, this research marks a significant step forward in safeguarding grape cultivation in Virginia and potentially reshaping strategies for controlling these persistent pests in vineyards. Growers and researchers alike eagerly await further developments and the practical application of these findings to protect the flourishing vineyards of the region. / Doctor of Philosophy / Mealybugs are common grapevine pests, recently causing a nuisance in vineyards across the United States and Canada. Some of the previously documented species of mealybugs common in the eastern part of the States include grape mealybug, obscure mealybug, Gill's mealybug, and long-tailed mealybugs. The research has mainly addressed the mealybugs and their tending ant species and their management in vineyards in Virginia. The study identifies grape mealybug and Gill's mealybug as the dominant species with occasional sightings of obscure mealybug and a lack of vine mealybug throughout the sampled vineyard sites. The male mealybugs were monitored using commercially available pheromone delta traps and adhesive band traps. Placement of adhesive band traps in the cordon and trunk of grapevines revealed different male mealybug capture data suggesting their movement within the grapevines. Two generations of mealybugs including the first generation with lower population density emerging out from the overwintering life-stage and the subsequent second generation responsible for colonizing different parts of the grapevines and producing overwintering life-stages were observed. Fifteen genera of ants were sampled from the vineyard via pitfall trap with some ants like pavement ants, acrobat ants, and medium garden ants actively tending and protecting the mealybugs. The use of sugar dispensers in the vineyards also led to lower fruit cluster infestations with mealybugs in comparison to the area without dispensers. The insecticidal spray trial using three different insecticides was also effective in controlling populations of mealybugs on some of the dates after treatment. The research offers valuable insights for grape growers, aiding in the development of effective control strategies for mealybug control. It emphasizes the importance of identifying the species present, understanding their behavior, and exploring potential allies and insecticide options in pest management.
20

A tecnologia da informa??o e o cliente banc?rio como recurso humano: um estudo de caso dos usu?rios dos caixas eletr?nicos nos postos banc?rios da UFRRJ. / The technology of the on line information and it s relationship with the costumer: a study of the users of the electronic cash dispenser in the advanced bank positions of UFRRJ.

Silva, Nic?as Alencar da 16 April 2004 (has links)
Made available in DSpace on 2016-04-28T20:19:19Z (GMT). No. of bitstreams: 1 2004 - Niceas Alencar da Silva.pdf: 808443 bytes, checksum: cd2525ca100feaf8969ca78945565665 (MD5) Previous issue date: 2004-04-16 / The study has focus in the bank user s behavior, presents in the electronic cash dispenser of the advanced positions of services of the Bank of Brazil and of the Real Bank, located in the campus of the Rural Federal University of Rio de Janeiro. It is centered in their perceptions of use of the Internet Banking, what generated the theme for the report of the evolution of the inclusion of the Technology Information in the banking sector. A questionnaire was distributed among the users of the electronic cash dispenser, after use, asking them on some personal characteristics - in order to identify statistical correlations - and also on their perceptions in the use of electronic cash dispenser and internet banking services, supplying data to the Bank Institutions, for a better strategic administration of their physical and human resources. The Study of the Case was the applied methodology, taking advantage of the natural atmosphere and giving emphasis to the present time, with access to the people and observation of the process in focus. The sampling is not probabilistic, consists of selecting the elements in function of it s presence at a specific moment (03-07/03/2003). The approach was in a driven way, through questionnaire with open and closed subjects and of multiple-choice. The banks has a relevant participation in the technological development of the country, when integrating, through the communication nets, the bank agencies, allowing transactions in real time. The study identified a high level of acceptance of Home Banking, in spite of being little used, what was justified mainly by the computer lack, as well as also the inaccessibility of the Internet. The ignorance and the resistance to the new technology were also mentioned, what implicates in another type of investment, in education, to be implemented for the customers to have capacity to execute the operations on line, including them to the digital access. A point of view to be considered is the cost of a customer not getting to accomplish his/her role, implicating in the loss of his/her self-esteem, need that if will not be taken care of, will be able to generate as result for the bank, the loss of the customer. For the company positioned in a competitive atmosphere, the ability to offer information, help in the construction of the image to the consuming public. / O estudo est? voltado para o comportamento dos usu?rios banc?rios, presentes nos Caixas Eletr?nicos dos Postos de Servi?os do Banco do Brasil e do Banco Real, localizados no campus da Universidade Federal Rural do Rio de Janeiro. Ele ? centrado nas suas percep??es de utiliza??o do Internet Banking, o que gerou o tema para o relato da evolu??o da inclus?o da Tecnologia da Informa??o no setor banc?rio. Um question?rio foi distribu?do entre os usu?rios dos Caixas Eletr?nicos, ap?s o uso, perguntando-os sobre algumas caracter?sticas pessoais de forma a identificar correla??es estat?sticas bem como, sobre suas percep??es no uso de Caixas Eletr?nicos e servi?os de Home banking, fornecendo subs?dios ?s Institui??es Banc?rias, para um melhor gerenciamento estrat?gico de seus recursos f?sicos e humanos. O Estudo de Caso foi a metodologia aplicada, por se tratar de um ambiente natural, dando ?nfase ? contemporaneidade, com acesso ?s pessoas e observa??o do processo em foco. A amostragem ? n?o probabil?stica, consiste em selecionar os elementos em fun??o de sua presen?a em um momento preciso (03-07/03/2003). A abordagem foi de forma dirigida, por meio de question?rio com quest?es abertas e fechadas e de m?ltipla-escolha. Os bancos representam um importante papel no desenvolvimento tecnol?gico do pa?s, ao integrar, atrav?s das redes de comunica??o, as ag?ncias banc?rias, permitindo transa??es em tempo real. O estudo identificou um n?vel elevado de aceita??o do Home Banking, apesar de ser pouco utilizado, o que foi justificado principalmente pela falta de computador, assim como tamb?m, a inacessibilidade da Internet. O desconhecimento e a resist?ncia ? nova tecnologia tamb?m foram citados, o que implica em outro tipo de investimento, em educa??o, a ser implementado para que os clientes tenham capacidade para executar as opera??es on line, incluindo-os no acesso digital. Um ponto de vista a ser considerado ? o do custo de um cliente n?o conseguir realizar o seu papel, implicando na perda de sua auto-estima, necessidade que se n?o atendida, poder? gerar como resultado para o banco, a perda do cliente. Para a empresa posicionada em um ambiente competitivo, a habilidade de oferecer informa??o, facilita a constru??o da imagem junto ao p?blico consumidor.

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