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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.
101

Potentiale zur Prozessoptimierung mittels adaptiver Bodenwerkzeuge

Bögel, Tim, Grosa, Andre, Herlitzius, Thomas 15 November 2017 (has links)
Motivation - Einsatz gezogener, passiver Werkzeuge als Universalgeräte zur Bodenbearbeitung Probleme: - Zugkraftbedarf - Verschleiß - Verfahrenssicherheit
102

Procesy odželezňování a odmanganování při úpravě podzemní vody / Removal of iron and manganese in water treatment process

Šafaříková, Jana January 2010 (has links)
This diploma thesis is aimed at the evaluation of water treatment technology in Písty waterworks which treats raw water with high concentration of iron and manganese. The most common method of iron and manganese removal from raw water is based on oxidation to insoluble hydrated oxides followed by separation of formed aggregates. The plant technology consists of aeration, oxidation agent KMnO4 dosing and mixing, sedimentation, filtration and hygienic protection. Chemical analysis of treated water, evaluation of the aeration efficiency of iron and manganese oxidation, evaluation of the separation efficiency of the sedimentation tank and filters, assessment of distribution of iron and manganese in the filter, assessment of dirt holding capacity and optimization of KMnO4 dose were determined. Raw water pH fluctuated around 7,3 during measurements, whereas iron and manganese concentrations in raw water were 6,00 and 0,82 mg.l-1 , respectively. Oxidation of 97,2 % of dissolved iron and of 14,3 % of dissolved manganese was achieved after the aeration. The separation efficiency of the sedimentation tank was 82,9 % for iron and 46,5 % for manganese, however the separation efficiency of the second half of the sedimentation tank was low. Thus, the perforated baffles in the second half of the sedimentation...
103

Implementación de una herramienta digital para la optimización de procesos de gestión de recursos humanos / Implementation of a digital tool for optimizing human resources management processes

Marin Liendo, Max Hernando, Melgar Zamudio, Marco Antonio, Zavalaga Bernedo, Annie Rocío 30 September 2020 (has links)
El contexto actual a nivel mundial posiciona la transformación digital como un medio indispensable para el desarrollo de las organizaciones desde diversas perspectivas y más aún donde los negocios globales se anclan de la tecnología para masificar los servicios y productos optimizando procesos que además contribuyan a la flexibilidad y continuidad de los negocios. Con esta investigación demostraremos la prioridad de implementar la plataforma digital en el área de recursos humanos de una financiera local que hemos tomado como fuente de estudio en cuanto a su operatividad y procesos que en su mayoría son realizados de forma manual para brindar atención a los 600 colaboradores a nivel nacional. En tal sentido, se identifica una oportunidad de mejora para gestionar con mayor eficiencia la información de recursos humanos a través de la implementación de una herramienta digital que facilite la autogestión de información y requerimientos por parte de los colaboradores, considerando los procesos que tiene implementado el área de recursos humanos, fuente que hemos utilizado para determinar y priorizar la funcionalidad de la plataforma digital. Producto de la investigación hemos identificado que el 52% de los colaboradores considera que la implementación de una plataforma digital tendrá impacto en la satisfacción laboral, el 21% en la comunicación interna, el 20% en la productividad y el 7% en la fidelización. Como podemos observar los cuatro factores descritos en el párrafo anterior además contribuyen en las acciones de retención que en empresas de este segmento suelen registrar altos niveles de rotación impactando en la productividad comercial, cumplimiento de metas y gestión de las carteras. Finalmente, de los trabajadores encuestados el 98% afirma que mejoraría su percepción respecto al área de recursos humanos si optimiza sus procesos a través de una herramienta digital y considerando que más del 60% muestra predisposición por el uso de la tecnología podemos afirmar que esta investigación es viable analizando el costo de inversión y beneficios múltiples por su implementación. / The current global context positions digital transformation as an indispensable means for the development of organizations from various perspectives and even more so where global businesses are anchored from technology to massify services and products optimizing processes that also contribute to the flexibility and continuity of business. With this research we will demonstrate the priority of implementing the digital platform in the human resources area of a local financial company that we have taken as a source of study regarding its operability and processes that are mostly carried out manually to provide attention to the 600 employees at the national level. In this sense, an opportunity for improvement is identified to more efficiently manage human resources information through the implementation of a digital tool that facilitates the self-management of information and requirements by employees, considering the processes implemented in the human resources area, a source that we have used to determine and prioritize the functionality of the digital platform. As a product of research we have identified that 52% of employees believe that the implementation of a digital platform will have an impact on job satisfaction, 21% on internal communication, 20% on productivity and 7% on loyalty. As we can see the four factors described in the previous paragraph also contribute to the retention actions that in companies in this segment often record high levels of turnover impacting commercial productivity, goal fulfillment and portfolio management. Finally, of the workers surveyed 98% say that it would improve their perception of the human resources area if they optimize their processes through a digital tool and considering that more than 60% shows predisposition for the use of technology we can say that this research is feasible analyzing the cost of investment and multiple benefits for its implementation. / Tesis
104

Propuesta de un modelo de Arquitectura Empresarial para una Corte Superior de Justicia

Benavides Bermúdez, José Justiniano, Cuba Peña, Rosario del Pilar, Huamán Aguilar, Rosario Vanesa, Mori Paiva, Hugo Allan 15 December 2020 (has links)
En nuestro país, el sistema de justicia se encuentra conformado por el Ministerio Público, el Tribunal Constitucional, la Junta Nacional de Justicia, la Academia de la Magistratura, y finalmente, pero no menos importante, el Poder Judicial. Esta última entidad mencionada, es un poder del estado que se encarga de administrar justicia a través de sus órganos jurisdiccionales, en base a la Constitución política del Perú y a sus leyes. El Perú debe realizar cambios en sus procesos para mejorar los diferentes servicios de justicia brindados. Para mejorar los servicios del Poder Judicial se propone implementar arquitectura empresarial, la cual permite alinear los objetivos estratégicos con las tecnologías de información. En la tesis “Propuesta de un modelo de Arquitectura Empresarial para una Corte Superior de Justicia” se desarrollará una propuesta de mejora de servicios a través de arquitectura empresarial a través de la metodología TOGAF. La propuesta comienza con el marco teórico que abarca conceptos de justicia, así como de arquitectura empresarial; luego se explica la situación actual del Poder Judicial, el planteamiento del problema y la justificación de este. A la mitad de la tesis se presenta el objetivo de la propuesta, seguida de la propuesta de solución al problema encontrado, para finalmente brindar las conclusiones y recomendaciones. Mediante el marco de trabajo Zachman se ha realizado el análisis de la situación actual por el cual se determinado que el macro proceso más importante es la “Gestión de procesos judiciales”; se ha usado el diagrama de causa – efecto para encontrar las causas del problema. La propuesta se ha desarrollado en base modelos de mejoras internacionales y una selección de buenas prácticas a través de un modelo propuesto de arquitectura empresarial. La presente tesis es una propuesta que debe servir como modelo para la implementación de una arquitectura empresarial en todo el Poder Judicial. / In our country, the justice system is formed by the Public Ministry, the Constitutional Court, the National Board of Justice, the Academy of the Magistracy, and last but not least, the Power of attorney. This last entity mentioned is a power of the state that is responsible for administer justice through its jurisdictional bodies, based on the Political Constitution of Peru and its laws. Peru must make changes in its processes to improve the different justice services provided. To improve the services of the Judiciary, it is proposed to implement business architecture, which allows aligning strategic objectives with information technologies. In the thesis "Proposal of a Business Architecture model for a Superior Court of Justice" a proposal for improving services through business architecture through the TOGAF methodology will be developed. The proposal begins with the theoretical framework that includes concepts of justice, as well as business architecture; then the current situation of the Judiciary, the approach to the problem and its justification are explained. In the middle of the thesis, the objective of the proposal is presented, followed by the proposed solution to the problem encountered, to finally provide the conclusions and recommendations. Through the Zachman framework, the analysis of the current situation has been carried out, whereby it was determined that the most important macro process is the "Management of judicial processes"; The cause - effect diagram has been used to find the causes of the problem. The proposal has been developed based on international improvement models and a selection of good practices through a proposed business architecture model. This thesis is a proposal that should serve as a model for the implementation of a business architecture throughout the Judiciary. / Tesis
105

Lean Six Sigma for In-Process Quality Improvement : Case Study of a Battery Cell Production Process

Bihi, Amiin January 2020 (has links)
Purpose The purpose of this thesis is to investigate the efficiency and performance of Quality control with focus on the inspections performed within production processes and how Lean Six Sigma can affect them. This can be done through mapping a current state to identify inefficiencies and wastes. The research will be used to answer following questions: How can Lean improve efficiency for in-process quality control? How can integration of Lean Six Sigma be applied to optimize processes? Can Six Sigma techniques increase the performance of quality control? Method A production process approach to quality control was investigated through a case study. Data was gathered through Interviews, Observations, Measurements and a Survey. The case study was complimented with Theory through a literature study which provided data from books and scientific articles. The literature study also created more room for generalization within the study as connection and conclusions could be made with results found in other works. Results Through the case study it was discovered that the production process under examination was working with Lean practices to a certain degree. Regarding Six Sigma, not much trace was found of using the concept and its methods in practice. It was exposed through Lean that there was waste generated within the process defined as motion, transport and inventory which could be eliminated to improve efficiency. Through Six Sigma there was noticed that implementation could be made to increase the performance of operators to detect deviations and generate more data for quality management within their quality inspections. Conclusion The conclusion drawn within the research based upon the case study and literature study is that an integration of Lean Six Sigma can be made to improve efficiency as well as performance of quality control within a production process. Lean tools can be used to improve speed of the process and utilization of resources. Meanwhile Six Sigma can be used to increase the ability to detect deviations and perform quality work. / Syfte Syftet med denna avhandling är att undersöka effektiviteten och prestanda för kvalitetsstyrning med fokus på de inspektionerna som utförs inom produktionsprocesser och hur Lean Six Sigma kan påverka dem. Detta kan göras genom att kartlägga ett aktuellt tillstånd för att identifiera ineffektivitet och slöserier. Forskningen kommer att användas för att besvara följande frågor: Hur kan Lean förbättra effektiviteten för kvalitetsstyrning under processen? Hur kan integration av Lean Six Sigma tillämpas för att optimera processer? Kan Six Sigma tekniker öka prestanda för kvalitetsstyrning? Metod En produktionsprocess arbetssätt med kvalitetsstyrning undersöktes genom ett upplägg likt en fallstudie. Data samlades in genom intervjuer, observationer, mätningar och en undersökning. Fallstudien kompletterades med teorin genom en litteraturstudie som tillhandahöll data från böcker och vetenskapliga artiklar. Litteraturstudien skapade också mer utrymme för generalisering inom studien då kopplingar samt slutsatser kunde göras med resultat från andra arbeten inom samma område. Resultat Genom fallstudien upptäcktes det att produktionsprocessen som undersöktes arbetade med Lean praktiskt till en viss grad. Gällande Six Sigma hittades det inte mycket spår utav användning av konceptet samt dess metoder inom praktiken. Det visades genom Lean att det fanns slöserier genererat inom processen definierad som rörelse, transport och lager som kunde elimineras för att förbättra effektiviteten. Genom Six Sigma märktes det att implementering kunde göras för att öka operatörernas prestanda för att upptäcka avvikelser och generera mer data för kvalitetsstyrning inom deras kvalitetsinspektioner. Slutsats Slutsatsen som dras inom studien som är baserad på fallstudien och litteraturstudien är att en integration av Lean Six Sigma kan göras för att förbättra effektiviteten såväl som prestandan av kvalitetsstyrning i en produktionsprocess. Lean verktyg kan användas för att förbättra processens hastighet och resursanvändning. Samtidigt kan Six Sigma användas för att öka förmågan att upptäcka avvikelser och utföra kvalitetsarbete.
106

Návrh automatizované kontroly výrobků na výrobní lince / Project of automated product control on production line

Pelcl, Milan January 2009 (has links)
This work deals with analysis one of the production lines at ModusLink Czech Republic s.r.o. It seeks to find possibilities for automation of different processes on the line, currently performed manually. The basic focus is to find the appropriate technical solutions to the automated control of the designated production line. The work seeks to describe all meaningful solutions and compare their advantages and disadvantages. From this comparison of the final proposal is based on comprehensive solutions with the use of machine vision. Another point is the selection of a suitable contractor for the implementation of the proposal, making its advantage in economic terms and the resulting recommendations, if implemented the proposal.
107

Einsatz von Prozessanalyse und Qualitätsregelkreisen zur Fehlervermeidung in der Fertigung von Gasdiffusionslagen

Müller, Richard 14 February 2019 (has links)
Aufgrund des weltweit steigenden Energiebedarfs, dessen Deckung derzeit größtenteils auf fossilen Brennstoffen basiert, ist es nötig geworden, die Entwicklung alternativer Möglichkeiten zur Erzeugung von Elektroenergie als Primärenergie voranzutreiben. Eine dieser alternativen Möglichkeiten ist die Brennstoffezellentechnologie, welche sowohl in stationären als auch mobilen Anwendungen zum Einsatz kommen kann. Ihrer weitreichenden Verbreitung stehen bislang die aufgrund des großen Fertigungsaufwandes hohen Herstellungskosten der benötigten Komponenten im Wege. Hierzu zählen die Gasdiffusionslagen des weit verbreiteten Typs der wasserstoffbetriebenen Polymerelektrolytbrennstoffzelle. Es treten zwischen den einzelnen Fertigungsschritten im Herstellungsprozess dieser Gasdiffusionslagen Wechselwirkungen auf, die zu unerwünschten Materialveränderungen führen. Die Ursachen dieser Wechselwirkungen sind nicht vollends verstanden. Eine Vertiefung des Verständnisses der Herstellungsprozesse soll die Grundlage für eine Optimierung der Prozessführung bilden. Es sollen eine Kostenreduktion sowie eine Leistungssteigerung der Gasdiffusionslagen ermöglicht werden.:1 Einleitung 1 2 Stand der Technik 5 2.1 Brennstoffzellen 5 2.2 Gasdiffusionslagen 11 3 Problemstellung und Zielsetzung 17 4 Analyse und Klassifizierung von GDL-Fehlern 20 4.1 Fehlerklassifizierung 22 4.2 Fehleridentifizierung 26 4.3 Auswahl zu analysierender Fehlerbilder 27 4.4 Charakteristika der ausgewählten Fehlerbilder 42 4.4.1 Bahndeformationen 42 4.4.2 Umlaufende Verdickungen von Wickeln in Umfangsrichtung 44 4.4.3 Längs- und Queraufrauhungen sowie Rauhspuren 45 5 Theoretische Grundlagen 49 5.1 Physikalische und mechanische Grundlagen 49 5.1.1 Zug-, Biege- und Druckspannungen in Warenbahnen 49 5.1.2 Elastizitäts- und Kompressionsmoduli 52 5.1.3 Elastizität und Plastizität 53 5.1.4 Umformmechanismen im GDL-Basisvliesstoff und Versagensarten von Fasern 54 5.2 Statistik 55 5.2.1 Korrelationsanalyse 55 5.2.2 Regressionsanalyse 56 5.2.3 Zweistichproben-t-Tests und Konfidenzintervalle 56 5.2.4 Stichprobenumfang 57 5.3 Qualitätsregelkreise 58 6 Eingesetzte Untersuchungsmethoden 60 6.1 Mechanische Eigenschaften 64 6.1.1 Höchstzugkraft und Höchstzugkraftdehnung 64 6.1.2 Elastizitätsmodul und Kompressibilität 66 6.1.3 Elastische und plastische Deformation bei Zugbelastungen 67 6.1.4 Flächenmasse 70 6.1.5 Biegesteifigkeit 72 6.1.6 Dickenmessung 74 6.2 Thermische Eigenschaften 75 6.2.1 Wärmeleitfähigkeit 75 6.3 Bildgebende Verfahren 78 6.3.1 Schliffbildmikroskopie 78 6.3.2 Rasterelektronenmikroskopie 78 6.3.3 µ-Computertomographie 79 7 Herstellungsverfahren der untersuchten Gasdiffusionslagen im Überblick 81 8 Basisvliesstoffherstellung 84 8.1 Prozess der Vliesbildung und Verfestigung 84 8.2 Charakterisierung des GDL-Basisvliesstoffes 90 8.3 Fehlerbilder des GDL-Basisvliesstoffes 103 9 Dickenkalibrierung 113 9.1 Prozess der Dickenkalibrierung des GDL-Basisvliesstoffes 113 9.2 Charakterisierung des dickenkalibrierten GDL-Basisvliesstoffes 120 9.3 Fehlerbilder des dickenkalibrierten GDL-Basisvliesstoffes 130 9.3.1 Prozessbeobachtung 130 9.3.2 Hypothesenbildung und Verifikation 135 9.3.3 Maßnahmen zur Fehlervermeidung 146 10 Carbonisierung 156 10.1 Prozess der Carbonisierung 156 10.2 Charakterisierung carbonisierten GDL-Substrates 157 10.3 Fehlerbilder im Carbonisierprozess 163 11 Data Mining für die GDL-Herstellung 167 11.1 Datenerhebung 167 11.2 Auszuwertende Parameter 172 11.3 Ergebnisse der Parameteranalysen 173 12 Qualitätsregelkreise zum GDL-Produktionsprozess 178 12.1 Wulstbildung und Längsaufrauhung 178 12.2 Queraufrauhung 181 13 Zusammenfassung und Ausblick 184 14 Literaturverzeichnis 186 15 Abbildungsverzeichnis 192 16 Abkürzungsverzeichnis 201 17 Formelverzeichnis 203 18 Anlagenverzeichnis 204 / Due to worldwide increasing energy consumption, which is mainly covered by fossile fuels nowadays, it has become a necessity to further develop alternative possibilities to create electricity as primary energy. One alternative technology to accomplish this is fuel cell technology which can be used in stationary as well as in mobile applications. One aspect hindering its widespread use is the high manufacturing cost of the needed components due to the complicated production processes. Among these are gad diffusion layers of the commonly used hydrogen-driven polymer electrolyte fuel cells. There are interactions occurring between the several production steps leading to unwanted changes in material properties. The causes of these interactions are not completely understood. A deeper understanding of these shall be the basis for optimizations in process design and therefore cost reductions and improvements in performance of gas diffusion layers can be achieved.:1 Einleitung 1 2 Stand der Technik 5 2.1 Brennstoffzellen 5 2.2 Gasdiffusionslagen 11 3 Problemstellung und Zielsetzung 17 4 Analyse und Klassifizierung von GDL-Fehlern 20 4.1 Fehlerklassifizierung 22 4.2 Fehleridentifizierung 26 4.3 Auswahl zu analysierender Fehlerbilder 27 4.4 Charakteristika der ausgewählten Fehlerbilder 42 4.4.1 Bahndeformationen 42 4.4.2 Umlaufende Verdickungen von Wickeln in Umfangsrichtung 44 4.4.3 Längs- und Queraufrauhungen sowie Rauhspuren 45 5 Theoretische Grundlagen 49 5.1 Physikalische und mechanische Grundlagen 49 5.1.1 Zug-, Biege- und Druckspannungen in Warenbahnen 49 5.1.2 Elastizitäts- und Kompressionsmoduli 52 5.1.3 Elastizität und Plastizität 53 5.1.4 Umformmechanismen im GDL-Basisvliesstoff und Versagensarten von Fasern 54 5.2 Statistik 55 5.2.1 Korrelationsanalyse 55 5.2.2 Regressionsanalyse 56 5.2.3 Zweistichproben-t-Tests und Konfidenzintervalle 56 5.2.4 Stichprobenumfang 57 5.3 Qualitätsregelkreise 58 6 Eingesetzte Untersuchungsmethoden 60 6.1 Mechanische Eigenschaften 64 6.1.1 Höchstzugkraft und Höchstzugkraftdehnung 64 6.1.2 Elastizitätsmodul und Kompressibilität 66 6.1.3 Elastische und plastische Deformation bei Zugbelastungen 67 6.1.4 Flächenmasse 70 6.1.5 Biegesteifigkeit 72 6.1.6 Dickenmessung 74 6.2 Thermische Eigenschaften 75 6.2.1 Wärmeleitfähigkeit 75 6.3 Bildgebende Verfahren 78 6.3.1 Schliffbildmikroskopie 78 6.3.2 Rasterelektronenmikroskopie 78 6.3.3 µ-Computertomographie 79 7 Herstellungsverfahren der untersuchten Gasdiffusionslagen im Überblick 81 8 Basisvliesstoffherstellung 84 8.1 Prozess der Vliesbildung und Verfestigung 84 8.2 Charakterisierung des GDL-Basisvliesstoffes 90 8.3 Fehlerbilder des GDL-Basisvliesstoffes 103 9 Dickenkalibrierung 113 9.1 Prozess der Dickenkalibrierung des GDL-Basisvliesstoffes 113 9.2 Charakterisierung des dickenkalibrierten GDL-Basisvliesstoffes 120 9.3 Fehlerbilder des dickenkalibrierten GDL-Basisvliesstoffes 130 9.3.1 Prozessbeobachtung 130 9.3.2 Hypothesenbildung und Verifikation 135 9.3.3 Maßnahmen zur Fehlervermeidung 146 10 Carbonisierung 156 10.1 Prozess der Carbonisierung 156 10.2 Charakterisierung carbonisierten GDL-Substrates 157 10.3 Fehlerbilder im Carbonisierprozess 163 11 Data Mining für die GDL-Herstellung 167 11.1 Datenerhebung 167 11.2 Auszuwertende Parameter 172 11.3 Ergebnisse der Parameteranalysen 173 12 Qualitätsregelkreise zum GDL-Produktionsprozess 178 12.1 Wulstbildung und Längsaufrauhung 178 12.2 Queraufrauhung 181 13 Zusammenfassung und Ausblick 184 14 Literaturverzeichnis 186 15 Abbildungsverzeichnis 192 16 Abkürzungsverzeichnis 201 17 Formelverzeichnis 203 18 Anlagenverzeichnis 204
108

[en] SIMULATION AND INTENSIFICATION OF BIODIESEL PRODUCTION PLANTS THROUGH HOMOGENEOUS AND HETEROGENEOUS CATALYSIS / [pt] SIMULAÇÃO E INTENSIFICAÇÃO DO PROCESSO DE PRODUÇÃO DO BIODIESEL A PARTIR DO ÓLEO DE SOJA VIA CATÁLISE HOMOGÊNEA E HETEROGÊNEA

CRISTIANE LEAL 05 October 2021 (has links)
[pt] O biodiesel é um biocombustível produzido tipicamente a partir da transesterificação e/ou esterificação, de óleos vegetais (ex. soja e dendê) que é constituído por diferentes tipos de ácidos graxos como, por exemplo, ácido oleico, linoleico, linolênico em composições distintas. Todavia, entre os artigos encontrados na literatura que abordam simulações e intensificação de processos industriais na produção do biodiesel, a composição química do óleo é simplificada, reduzindo-se ao triglicerídeo de maior concentração. A fim de analisar a intensificação do processo de obtenção de biodiesel, a partir do óleo de soja, utilizando destilação reativa, inicialmente, foi realizado a comparação das propriedades do biodiesel, como densidade, viscosidade e composição, produzido via catálise homogênea e heterogênea, considerando-se a composição química total do óleo de soja e considerando apenas o triglicerídeo majoritário, composto por uma molécula de ácido oleio e duas de ácido linoleico. A análise confirmou que não há alteração significativa nos resultados em substituir a composição do biodiesel por uma fração única de triglicerídeos, devido à proximidade de propriedades físico-químicas. Visto isto, o desenvolvimento da simulação e intensificação do processo foi desenvolvido a partir do componente majoritário no óleo de soja. Considerando o déficit de informações completas relacionando os estudos de composição, destilação reativa, integração energética e avaliação econômica, a tese complementa uma metodologia para simular a produção do biodiesel via catálise homogênea e heterogênea, utilizando a destilação reativa (DR), integração energética e considerando a viabilidade financeira de todos os fluxogramas estudados. Nas simulações desenvolvidas resultaram um melhor aproveitamento da energia presente nos correntes quentes disponíveis, e assim reduzindo-se o investimento em utilidades. Concluiu-se que ao empregar a destilação reativa, para catálise homogênea e heterogênea, há energia a ser economizada, em torno de 30 a 48 por cento, ou seja, há disponibilidade de modificação no processo para que ocorra um melhor aproveitamento e economia de energia. A partir disto, empregou-se a integração energética, utilizando o sistema de reaproveitamento energético, obtendo um melhor cenário para o estudo energético proporcionando uma economia de 70 por cento e 65,8 por cento de energia nos processos homogêneo e heterogêneo, respectivamente. Quanto à viabilidade econômica, considerou-se a capacidade do processo com vida útil de 15 anos e as simulações indicaram rendimentos positivos e sugere-se serem viáveis economicamente. Porém, ao empregar a destilação reativa com intensificação do processo, a redução de gastos energéticos e financeiros com o catalisador heterogêneo se mostrou ser a melhor opção energeticamente e economicamente. Comparando o sistema com gastos, o inicial homogêneo, com o econômico, dito anteriormente, a economia de energia das utilidades foi em torno de 80 por cento e a diferença no valor presente líquido (VPL) de 744.089,84 de dólares. O resultado mostrou que o investimento em mais trocadores de calor de correntes de processo somados à redução de equipamentos da via por catalise heterogênea permitiu alcançar uma relação de custo alternativa mais atraente que o processo tradicional via catálise homogênea ainda que o custo do catalisador seja maior no caso heterogêneo. / [en] Biodiesel is a biofuel typically produced from transesterification and/or esterification of vegetable oils (eg soy and palm oil) which is made up of different types of fatty acids such as, for example, oleic, linoleic, linolenic acid in different compositions. However, among the articles found in the literature that address simulations and intensification of industrial processes in the production of biodiesel, the chemical composition of the oil is simplified, reducing it to the highest concentration triglyceride. In order to analyze the intensification of the process of obtaining biodiesel from soybean oil, using reactive distillation, initially, a comparison of the properties of biodiesel, such as density, viscosity and composition, produced via homogeneous and heterogeneous catalysis was performed, considering - the total chemical composition of soybean oil and considering only the major triglyceride, composed of one molecule of oleic acid and two of linoleic acid. The analysis confirmed that there is no significant change in the results in replacing the biodiesel composition with a single fraction of triglycerides, due to the proximity of physicochemical properties. In view of this, the development of simulation and process intensification was developed from the major component in soybean oil. Considering the lack of complete information relating composition studies, reactive distillation, energy integration and economic evaluation, the thesis complements a methodology to simulate the production of biodiesel via homogeneous and heterogeneous catalysis, using reactive distillation (DR), energy integration and considering the financial feasibility of all studied flowcharts. The simulations developed resulted in a better use of the energy present in the available hot currents, thus reducing the investment in utilities. It was concluded that when using reactive distillation, for homogeneous and heterogeneous catalysis, there is energy to be saved, around 30 to 48 percent, that is, there is availability of modification in the process so that there is a better use and energy saving. From this, energy integration was used, using the energy reuse system, obtaining a better scenario for the energy study, providing savings of 70 percent and 65.8 percent of energy in homogeneous and heterogeneous processes, respectively. As for the economic feasibility, it was considered the capacity of the process with a useful life of 15 years and the simulations indicated positive yields and are suggested to be economically viable. However, by employing reactive distillation with process intensification, the reduction of energy and financial costs with the heterogeneous catalyst proved to be the best option energetically and economically. Comparing the system with expenses, the initial homogeneous, with the economic, mentioned above, the energy savings of the utilities was around 80 percent and the difference in the net present value (NPV) of 744,089.84 dollars. The result showed that the investment in more process current heat exchangers, added to the reduction of equipment in the heterogeneous catalysis path, allowed to reach a more attractive alternative cost ratio than the traditional process via homogeneous catalysis, even though the cost of the catalyst is higher in the heterogeneous case.
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Evaluation Of An On-line Device To Monitor Scale Formation In A Brackish Water Reverse Osmosis Membrane Process

Roque, Jennifer C 01 January 2012 (has links)
A modified two-element membrane pressure vessel assembly has been used to monitor process operational changes in a full-scale reverse osmosis (RO) water treatment plant (WTP). This study evaluated the effectiveness of the assembly as an on-line monitoring device intended to detect scale formation conditions when connected to an operating RO process train. This study was implemented to support the requirements of a larger University of Central Florida (UCF) research project ongoing at the city of Sarasota’s Public Works and Utilities (City) water treatment facilities located in Sarasota, Florida. During the time-frame of this study, the City was in the process of eliminating their sulfuric acid feed from the pretreatment system of their existing 4.5 million gallon per day (MGD) RO membrane process. The City was motivated to eliminate its dependence on sulfuric acid to reduce operating costs as well as reduce operation health and safety risks associated with the use of the acid as a pretreatment chemical. Because the City was concerned with secondary process impacts associated with acid elimination, additional measures were desired in order to protect the full-scale process. This thesis reports on the design, fabrication and installation of a third-stage two membrane element pressure vessel “canary” sentinel monitoring device (Canary), its effectiveness as an online scaling monitor during full-scale acid elimination, and presents the results of the study. The Canary sentinel device was controlled using the normalized specific flux of the two membrane elements fed by a portion of the second stage concentrate of one of the City’s full-scale RO process skids. Although the Canary demonstrated the ability to detect changes in an RO process operation, scaling did not occur under the conditions evaluated in this study. An autopsy of one iv of the Canary elements revealed that no scaling had occurred during the acid elimination process. Therefore, the Canary was found to be useful in its function as a sentinel, even though no scaling was detected by the device after acid elimination at the City’s full-scale plant had been accomplished.
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Повышение конкурентоспособности предприятия сферы услуг общественного питания на основе Бережливых технологий : магистерская диссертация / The competitiveness improving of catering enterprise based on Lean technologies

Патракова, Д. И., Patrakova, D. I. January 2019 (has links)
Диссертация посвящена проблеме повышения конкурентоспособности компании путем использования новых управленческих технологий. Речь идет, в первую очередь, о внедрении в деятельность предприятия, работающего в сфере услуг, концепции бережливого производства. Данная концепция представляет собой набор конкретных методов и технологий, направленных на повышение конкурентоспособности предприятия за счет сокращения различного рода потерь как в системе производства, так и в системе потребления. Для повышения конкурентоспособности предлагается использовать неценовые методы конкуренции, а именно: повышение потребительской ценности в процессе обслуживания клиентов. Таким образом, завоевание конкурентного преимущества будет достигаться путем сервисной дифференциации. Для оптимизации деятельности предприятия были определены основные процессы, происходящие при обслуживании, и выбраны наиболее значимые с точки зрения конкурентных позиций, которые необходимо оптимизировать в первую очередь. Для каждого процесса был сформирован поток создания ценности, определены потери и их виды, а также разработаны мероприятия по снижению или исключению этих потерь. / The thesis is devoted to the problem of increasing the competitiveness of the company by using new management technologies. It is, first of all, the introduction of the concept of lean production in the activities of the enterprise operating in the service sector. This concept is a set of specific methods and technologies aimed at increasing the competitiveness of an enterprise by reducing various kinds of losses, both in the production system and in the consumption system. To increase competitiveness, it is proposed to use non-price methods of competition, namely, increase of consumer value in the process of customer service. Thus, the achievement of a competitive advantage will be achieved through service differentiation. To optimize the activities of the company, the main processes that took place during maintenance were identified, and the most significant ones were selected from the point of view of competitive positions, which should be optimized in the first place. For each process, a value stream was generated, losses and their types were identified, and measures were developed to reduce or eliminate these losses.

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