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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

O saneamento e as águas de Bauru : uma perspectiva histórica (1896 -1940) /

Gulinelli, Erica Lemos. January 2016 (has links)
Orientador: Nilson Ghirardello / Banca: Nilson Ghirardello / Banca: Norma Regina T. Constantino / Banca: Maria Angela Pereira de Castro e Silva Bortolucci / Resumo: O Saneamento e a questão das águas urbanas são pertinentes e importantes para as cidades na atualidade. Entendendo as origens, problemas e conflitos do passado, pode-se discutir possíveis soluções para as adversidades diárias no momento contemporâneo. Desta forma, muitas poderiam ter sido as perspectivas para analisar o percurso pela história do saneamento da cidade. Contudo, o olhar dado a esta pesquisa parte de um questionamento central: o princípio estruturador para a coleta de referências e informações, como também, serviu de base para análises ao longo do texto. Tal questão pode ser formulada assim: como se deu a trajetória histórica do saneamento na cidade de Bauru atrelada aos aspectos do desenvolvimento econômicos, sociais, políticos e culturais, no período de sua formação urbana até a década de 1940? Percebe-se que o saneamento é visto como medida higienizadora e de embelezamento do ambiente construído, com a finalidade de prevenir doenças e manter a assepsia. A infraestrutura de água e esgoto constituiu-se como um meio de minimizar as questões relacionadas com a higiene urbana da cidade. A literatura que trata a história de sanear a cidade de Bauru é fragmentada e escassa, baseada em relatos de memorialistas. Assim, opta por uma análise integrada dos setores da história urbana, do saneamento e da saúde (por meio de ações sanitárias) com a finalidade de entender sua intrínseca relação com a demanda social, embasando-a em fatos históricos e documentação primária e téc... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Sanitation and urban waters are greatly relevant and important to the cities nowadays. Understanding the origins, problems and conflicts of the past, we can discuss possible solutions for everyday adversities. The perspectives concerning to the analysis of this matter could have been done by many ways throughout the city's sanitation history. However, the overview aimed at this research is a part of a central question, which concerns to the structuring principle of collecting references and information to make it serve as basis for analysis throughout the dissertation. This hypothesis can be formulated as the question that follows: how did the historical trajectory of sanitation in the city of Bauru tied aspects of economic, social, political and cultural development, from its urban conformation in the 1940s? It is perceived that sanitation regards both to hygiene and to environmental beautification, a concept built for the purpose of prevention of diseases and asepsis. The infrastructure of water and sewage constituted a means to minimize issues related to the urban hygiene of the city. The literature on the history of cleansing up the city of Bauru is fragmented and scarce, based mainly on memoir reports. That is why this research aims to present an integrated analysis of the sectors of urban history, sanitation and health (through sanitary actions) in order to understand its intrinsic relationship to the social demand, basing it on historical facts and technical documentat... (Complete abstract click electronic access below) / Mestre
12

Analysis and management of wood room

Isokangas, A. (Ari) 10 August 2010 (has links)
Abstract The objective of this work was to study the effect of adjustable process parameters on wood loss and bark removal in tumble drum debarking. The effect of capacity on the size distribution of the chips was studied in order to determine the optimal capacity for both the debarking and chipping sub-processes. The final aim was to propose a control strategy to optimise the processes by adapting their parameters according to the quality of the raw material. When the research started, earlier automation systems had focused on keeping the process alive, and economic values such as wood loss were not considered important. The process is usually controlled manually and shifts have different ways to manage it, which are based on trial and error. Bark removal in chemical pulp mills is usually higher than the values recommended in the literature, which in turn causes log breaking in the drum and increases wood loss. Even a small reduction in wood loss could have a substantial financial outcome. The lack of raw materials some time ago and the recession nowadays have highlighted the importance of more efficient log use. Data survey techniques were employed to reveal the interactions between drum variables from noisy measurements. Wood room data were analysed by modelling and deriving conclusions from the resulting parameters. In addition, log breaking and the size distribution of the chips were analysed under different process conditions. A pilot-scale drum was used to study residence time and the mechanical abrasion of logs. The results of this work indicated that the ratio of the volume of logs in the drum to capacity determines the residence time of the logs in the drum. Other variables influence the volume of logs in the drum, which together with capacity determine the residence time of logs in the drum, which affects wood loss and bark removal. The effect of capacity on the size distribution of the chips was not unambiguous, however, and it was therefore recommended to operate wood room at high capacity, because this reduces wood loss and increases annual production. The proposed control strategy adapts the residence time of logs in the drum to the quality of the debarked raw material by controlling the position of the closing gate. In addition, the control strategy adjusts the rotating speed of the drum using an open loop control. The results can be used to optimise the wood room process parameters. If the problem in wood room is excessive debarking, the residence time of the logs can be reduced and the rotating speed of the drum lowered. In this way the logs will be damaged less and wood loss will be reduced. Bark removal requirements in mechanical pulp mills are high, and the process parameters can be adapted to avoid problems in the subsequent processes due to excessive bark.
13

Building a GIS Web Service for Mobile Phone and Evaluating its Usability : Case study – A cleanliness index GIS

Boström, Joel January 2016 (has links)
This study aims to identify key usability factors in a GIS (Geographical Information System) web service for mobile phone. The study also includes a usability evaluation of such a prototype. The prototype was created with the objective of evaluating the cleanliness in the city of Gävle and involving the users in keeping the city clean. Research on the subject of usability was performed in preparation for the development of the prototype. The subsequent usability test that was performed showed that the prototype was highly usable in consideration to efficiency, learnability and satisfaction. However in regards to effectiveness, the prototype was in its current state not highly usable.
14

Renhetens inverkan på vidhäftningen mellan gammal betong och pågjutning / The influence of cleanliness on the bond between old concrete and a new-cast concrete overlay

Ndayizeye, Fernand, Abdiraxman, Maxamed January 2012 (has links)
Detta examensarbete har genomförts på uppdrag av CBI Betonginstitutet. Handledare till examensarbetet har varit professor Johan Silfwerbrand från CBI och examinator Per Roald från Kungliga Tekniska Högskolan i Haninge.  Idag är betong ett byggmaterial som används i stor omfattning tack vare sin beständighet, miljövänlighet och lönsamhet. Betong hittar man i både gamla och nyproducerade konstruktioner. Även med bra egenskaper kan betong vara ofullkomlig när den prepareras på fel sätt.  För att underlätta gjutning och arbetbarhet av betong användes förut i många fall mycket vatten och detta resulterade i att beständigheten på betong försämrades. De flesta gamla betongkonstruktionerna är nu i stort behov av renovering. Det synliga beviset kan vara spricknärvaro på ytan och detta kan ha följd att vatten tränger in och orsakar bland annat frost- och saltangrepp samt korrosion i armering. Betong som är skadad eller sliten kan behöva renoveras genom att avverkas delvis eller helt. För att hitta en lämplig avverkningsmetod och reparationsmaterial behöver man först ta reda på skadorna, ställa krav på lagningen, tänka på hur lagningen kommer att utföras och hur upprepningen av skadan ska förebyggas. För att reparera den skadade betongen, avverkas den först och sedan gjuts pågjutningar på den friska och kvarstående delen. Pågjutningar används även i flerskiktsgolv t ex gjuts pågjutningar på prefabricerade bjälklag i olika köpcentrum. Det finns flera typer av bilningsmetoder och de påverkar den kvarstående betongen på olika sätt. De mest använda metoder är vattenbilning och hydraulisk bilning. Vattenbilning är den mest använda inom anläggningssektorn och den effektivaste och lönsammaste metoden. Betongen bilas bort med högtrycksvatten och lämnar en grov och skonsam yta på den friska betongen. Hydraulisk bilning är den äldsta, billigaste och enklaste metoden men nackdelen är att den orsakar mikrosprickor i den friska betongen. Efter betongbilningen måste man se till att man har förutsättningar för en god vidhäftning mellan gammal och pågjuten betong. Vidhäftning är beroende av ett antal faktorer och de fem viktigaste av dem är renhet, mikrosprickfrihet, frånvaro av cementhud, god kompaktering och god härdning.  I första delen av examensarbetet testas en provningsmetod som mäter hur ren en motgjutningsyta är. I detta fall används en vit mikrofiberduk som krontrollmätare på renhet. Olika varianter av smuts applicerades på ytan av en betongplatta för att testa mikrofiberdukens uppsugningsförmåga. Mikrofiberduken S-sveptes över den smutsiga betong ytan och redan där sågs det tydligt hur bra mikrofiberduken är på att absorbera smuts. På samma sätt utfördes det på en ren yta och den använda duken förblev vit vilket är ett tydligt bevis på att ytan på betongplatta är helt ren och redo för pågjutning.  Examensarbetets andra del tar upp en jämförelse mellan vidhäftningen på en ren pågjuten motgjutningsyta och en oren motgjutningsyta. Vi studerade renhetens inverkan på vidhäftningen mellan gammal och pågjuten betong och som avverkningsmetod användes vattenbilning. För att utföra det, har två betongplattor gjutits och sedan vattenbilats. Den bilade ytan på både plattorna delades i olika delar, där olika varianter av smuts applicerades på halva betongplattan och andra halvan var den rena referensen. Efter detta göts ny, pågjuten betong på båda betongplattorna. Fyra veckor senare togs dragtester för att se om draghållfasthet försämras i över-, underbetong eller i fogen på grund av orenhet jämfört med referensen.  Renhet har en stor påverkan på vidhäftningen mellan gammal och ny, pågjuten betong. Draghållfastheten försämras om motgjutningsytan inte är helt ren. Beviset är ett brott i fogen mellan betongskikten, med en väldig liten dragkraft och det syns tydligt att smuts som olja eller träflis precis i fogen när borrcylinder dras ut. För att lösa problemet rekommenderas att använda en vit mirakel duk för att vara säker att motgjutningsytan är helt ren innan pågjutningar gjuts på och detta bevisas med en oförändrad vit färg på duken. / This Bachelor’s thesis project has been commissioned by Swedish Cement and Concrete Research Institute. Our supervisor for this thesis project has been Prof. Johan Silfwerbrand and examiner Per Roald from The Royal Institute of Technology in Stockholm. Nowadays, concrete is a building material that is widely used because of its durability, environmental friendliness and profitability. Concrete can be found in both old and new designs produced. Even with good performance concrete can be imperfect when it is prepared incorrectly. To facilitate the handling of concrete plenty of water was often used before and this resulted in concrete deterioration. Many old concrete structures are now in great need of renovation. The visible proof can be the presence of micro cracking on the surface and this may be due to the ingress of water in the concrete and causes including freezing and salt attack and corrosion of the reinforcement.   Concrete that is damaged or worn may need to be removed partly or completely. Appropriate removal methods and repair materials are needed, the causes of damage has to be determined, establishing of requirements for repair of concrete, the process of repairing has to be settled and the prevention of the repetition of the damage has to be determined. The damaged concrete has to be removed and be replaced by new overlay concrete. The overlay concrete is used as well in multi-layer floor, for example in various shopping centers overlay concrete is placed on precast slabs. There are several methods of concrete removal and they have different impact on the surface of the remaining concrete. The most widely used methods are the water jet and the hydraulic jetting. Water jet or hydro demolition is the most widely used in civil engineering sector and an efficient and profitable method. The concrete is removed by high pressure water that leaves a rough and gentle surface of the remaining concrete. Hydraulic jetting is the oldest, most common method and easiest concrete removal method. The negative impact of this method is that it causes micro cracks on the remaining concrete.  After the concrete has been removed there is a need to ensure that the conditions of getting a good bond between the old concrete and the overlay concrete are there. A good bond is dependent on a number of factors, and five of them are most important: micro cracks absence, the absence of laitance layer, cleanliness, high compaction and good curing.   In the first part of the thesis it is tested a test method that measures how clean the surface, there the overlay concrete will be placed, is. In this case, a white microfiber cloth is used as the crown control measure of cleanliness. Different types of dust and contaminations are applied to the surface of a concrete slab to test the cloth’s capacity to absorb the contaminations. The microfiber cloth is swept with S-pattern onto the contaminated concrete surface and already there it was obvious how good microfiber cloth is at absorbing dirt. In the same way this process was performed on a clean surface and the cloth remained white which is a clear proof that the surface of the concrete slab is perfectly clean and ready for casting.  The second part of this thesis deals with a comparison between the adhesion to a clean surface and unclean one. We study the effect of cleanliness on the bond between old concrete and a new-cast concrete overlay with water jet as a removal of the old concrete. To perform it, two concrete slabs were cast and then water jetted. The jetted surfaces of both slabs were divided into different zones, in which different varieties of contaminations were applied to half of the concrete slab and the other half remained clean as a reference zone. After this step the overlay concrete was cast on the surface of both concrete slabs. Four weeks later the test of the tensile bond strength was performed to observe where the strength has been poor and where the fracture of the concrete slabs has been, in other words if the fracture will be whether in the new-cast overlay concrete, in the bond zone or in the substrate concrete.   Cleanliness has a profound influence on the bond between old and new cast concrete. The tensile strength is poor on the concrete where the surface wasn’t clean enough. The proof is a fracture on the bond between the concrete layers, with less tension force and it is clearly visible dirt such as oil or chips just on the interface when the drilling cylinder is pulled out. To solve this problem it is advised to use a white miracle cloth to be sure that the surface is completely clean before placement of the new-cast concrete.
15

“Cleanliness in Antebellum Detroit: Urban Development of Nineteenth-Century Private and Public Spheres in Detroit, Michigan”

Whitehill, Kathryn M. January 2020 (has links)
No description available.
16

Small Satellite Design for High Sensitivity Magnetic Measurements

Janes, Noel Sebastian January 2022 (has links)
The magnetic cleanliness of a spacecraft during magnetic measurements is an important aspect in the design of many space science missions. The adequate reduction or removal of the spacecraft's magnetic disturbance plays a vital role in allowing the ambient magnetic field to be measured with the required accuracy. There are three main approaches to reduce the impact of the spacecraft's magnetic disturbance on the final magnetic measurement, with each approach imposing its own set of changes and constraints on the spacecraft. In turn these changes and constraints introduce additional complexity and cost to the system design. The required changes in the spacecraft's mission profile and configuration also need to be factored in during the design phase of a spacecraft, but cannot be avoided if high quality measurements are desired.  One of these approaches is the use of a magnetic cleanliness programme, and such programmes have a long history of successful use on large satellite missions.CubeSats have become increasingly technically capable and have in recent years begun to undertake scientific missions with challenging sensitivity requirements, including for magnetic measurements. The small size of the CubeSat form factor poses some unique challenges to the implementation of magnetic cleanliness techniques, but are also in increased need of limiting the residual magnetic moment when compared to large satellites. This thesis details the early phases of the magnetic cleanliness programme on the FORESAIL-2 science mission. Nine magnetic cleanliness requirements on the FORESAIL-2 satellite platform were derived from the FORESAIL-2 measurement and instrument requirements. A simple magnetic model was established, the results of which were used to propose a configuration of spacecraft subsystems. The resulting preliminary configuration of subsystems reduced the effective magnetic field of the REPE payload at the sensor by 352pT, 30.1%, when compared to the worst-performing configuration. Subsequently an improved model, utilising RSS analysis, was created. Combined with updated location information for each subsystem, defined using the proposed configuration, this second model yielded an estimated magnetic field of 2710pT at the reference point. The results of the second model were also used to identify the CDE payload and the TT&C subsystem as potentially problematic from a magnetic cleanliness perspective. A list of ferromagnetic materials was compiled, and a total mass of 453.72g of ferromagnetic materials was estimated. The work presented in this thesis is expected to form the basis of FORESAIL-2's continued magnetic cleanliness programme throughout the design and integration phases of the project.  For example, the improved model could be extended to include the estimated magnetic dipole moment's of each subsystem. Additionally, the inventories of materials, currents, and frequencies established as part of this thesis can be maintained throughout the FORESAIL-2's development cycle, and used to update the estimated total magnetic field of the spacecraft platform.
17

Zavedení managementu čistých komponent / Cleanliness of components management implementation

Sojáková, Šárka January 2012 (has links)
Presented thesis entitled “Cleanliness of components management implementation” with analysis of the currently applied cleanliness management system in the organization, identification of the root causes of contamination in production, suggestion of the possible solution and recommendation of actions. All material presented in this thesis were collected in Mann+Hummel (CZ) s.r.o., a producer of filters and fluid circuits for automotive industry.
18

Six Sigma for quality assurance of Lithium-ion batteries in the cell assembly process : A DMAIC field study at Northvolt / Sex Sigma för kvalitetssäkring av Litium-jon batteriers cellmonteringsprocess : En fältstudie enligt DMAIC på Northvolt

Mostafaee, Mani January 2021 (has links)
Lack of technical cleanliness and particle contaminations in Lithium-ion battery manufacturing affect the performance of batteries which are a risk for the safety and quality of the product. Therefore, part of the manufacturing process occurs inside the Clean and Dry room area to maintain technical cleanliness. This paper aims to provide a framework to control particle contamination inside the Clean and Dry room and strengthen the product's quality and safety. A literature study was conducted, which was completed by a field study at Northvolt Labs in Västerås to achieve the study's aims. The study contributes to existing theories by providing a framework to find root causes of particle contamination in the manufacturing process based on the existing literature and standards. The Six Sigma problem-solving methodology DMAIC was implemented to conduct the field study. A risk assessment was conducted to find the possible threats toward technical cleanliness in the cell assembly process. The risk sources were identified by implementing measurement methods from relevant standards. The results indicate a high risk for technical cleanliness are coming from the decontamination method, material, machines, and environment. Furthermore, several recommendations were given that are expected to decrease the amount of nonconformity in the process. / Brist på teknisk renhet och partikelföroreningar vid tillverkning av litiumjonbatterier påverkar dess prestanda och utgör en risk för produktens säkerhet och kvalitet. Därför sker en del av tillverkningsprocessen i ett Clean & Dry rum för att upprätthålla teknisk renhet. Denna uppsats syftar till att ge ett ramverk för att kontrollera partikelföroreningar och därmed stärka produktens kvalitet och säkerhet. För att uppnå syftet genomfördes först en litteraturstudie vilket vidare kompletterades med en fältstudie vid Northvolt Labs i Västerås. Studien bidrar till befintliga teorier genom att tillhandahålla ett ramverk för att hitta och åtgärda rotorsaker till partikelkontaminering i tillverkningsprocessen baserat på befintlig litteratur och standarder. Sex Sigma problemlösningsmetoden DMAIC implementerades för att genomföra fältstudien. En riskbedömning genomfördes för att hitta riskfyllda aktiviteter i processen. Vidare implementerades mätmetoder från relevanta standarder för att mäta kontamineringsnivån. Resultaten indikerar stor risk för tekniskrenhet från saneringsmetoder, material, maskiner och miljön. Vidare rekommenderas flera åtgärder för att underhålla tekniskrenhet vilka förväntas minska avvikelser i processen.
19

Development of an Accelerated Test Method for Compressed Natural Gas Fuel System Robustness against Contamination

Aretorn, Elias January 2023 (has links)
A key factor for driving the shift towards sustainable transportation systems is alternative fuels, where compressed natural gas (CNG) is a beneficial alternative to the conventional fossil fuels with respect to greenhouse gas emissions. A fuel system is needed for heavy-duty natural gas vehicles, in order to transport the highly pressurized gas from the fuel tanks to the internal combustion engine. The fuel system can be contaminated from several different sources – carry-over compressor oil from refuelling stations, water already present in the gas, manufacturing residuals and road dust entering the fuel system via the receptacle valve. The contaminants can induce fuel system failure modes, leading to poor engine performance, increased emissions or gas pressures above component pressure ratings. The objective of this thesis was to develop an accelerated test method to evaluate CNG fuel system robustness against contamination, to be able to prevent CNG fuel system failures and to ensure a high-quality product. The experimental setup was developed to be installed on a truck in order to utilize already present surrounding systems. The setup enables performance testing of six out of nine components belonging to the fuel system, which can be tested individually or combined in an arbitrary way. The setup induces premature failure modes primarily through excessive contamination in a controlled manner. An experimental procedure has been developed as a complement. Validation of metrics through testing is needed before the test method can be considered finalized. / En nyckelfaktor för att driva omställning mot hållbara transportsystem är alternativa bränslen, varpå naturgas (CNG) är ett slagkraftigt alternativ till konventionella fossila bränslen med avseende på utsläpp av växthusgaser. För att kunna transportera den högt trycksatta gasen från bränsletankarna till förbränningsmotorn krävs ett bränslesystem för tunga naturgasfordon. Bränslesystemet kan kontamineras genom ett flertal olika källor – överförd kompressorolja från tankstationer, vatten som redan finns i gasen, tillverkningsrester och vägdamm eller grus som tar sig in i systemet genom bränslepåfyllningsventilen. Kontamineringen kan ge upphov till felmoder i bränslesystemet, vilket leder till låg motorpresentanda, ökade utsläpp eller övertryck i systemet. Syftet med examensarbetet var att utveckla en accelererad testmetod för att utvärdera CNG-bränslesystems robusthet mot kontaminering, för att kunna förebygga systemfel och säkerställa en högkvalitativ produkt. Den experimentella uppställningen utvecklades för att monteras på lastbil, för att på så vis nyttja de kringliggande befintliga systemen. Uppställningen möjliggör prestandaprovning av sex av nio komponenter som tillhör bränslesystemet, som kan testas individuellt eller kombineras på ett godtyckligt sätt. Uppställningen framkallar tidiga felmoder, huvudsakligen genom excessiv kontaminering på ett kontrollerat vis. En metodbeskrivning har utvecklats som ett komplement till den experimentella uppställningen. Validering av metrik genom testning är nödvändigt för att finna testmetoden färdigställd.
20

The Relative Contribution of Health-Care Points of Service to Overall Patient Satisfaction at a University Health Center

Parikh, Jay M 01 January 2023 (has links) (PDF)
Throughout the process of receiving healthcare, a patient is affected by several factors and processes. To just name a few, how long a patient must wait at the clinic, how friendly the front desk is, how the nurse treats the patient, how effective the physician is with his or her communication, what the cost of a patient's healthcare is, and how clean the clinic is all affect the patient's experience. When clinics excel in these factors, it promotes a favorable relationship between the patient and the clinic. Patients trust the healthcare provider and desire to continue attending that clinic when they need to. Unfortunately, not every clinic can succeed in all these factors. The purpose of this study was to investigate the relative importance of these factors in a patient satisfaction survey at a university health center.

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