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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.
141

Propuesta de rediseño geométrico de la intersección de la Av. Argentina y Jr. Pacasmayo para la reducción de las demoras por control

Pérez Gutiérrez, Gianfranco, Ramos Lazo, Bryhan Frankgdiff 29 November 2020 (has links)
El transporte vial representa unos de los ejes principales para el desarrollo y crecimiento de un país. No obstante, existen diversos factores por el cual este importante recurso no se desarrolla con total eficiencia. Uno de estos es representado por la alta densidad demográfica en las urbes y su rápido crecimiento anual, dando cabida a uno de los mayores efectos negativos en ciudades que no ponen mayores esfuerzos en cuanto a gestión y planificación urbana, el congestionamiento vehicular. Anualmente, el crecimiento del parque automotor responde a la necesidad de un mayor número de personas que tienen como una sus principales necesidades, trasladarse de un lugar a otro, por distintos motivos. Esto genera que la cantidad de vehículos se incremente de forma incontrolable, haciendo que la calidad de los sistemas viales no sean los más óptimos. Una forma de medir la calidad de los sistemas de transportes es por medio de sus tiempos de viaje. En América Latina, el tiempo de viaje promedio es de 64 minutos. Dentro de esta estadística se encuentra la ciudad de Lima, el cual presenta un tiempo de viaje promedio de 82 minutos. Convirtiéndose en una de las ciudades con la calidad de sistema de transporte menos eficiente en la región. El congestionamiento en la ciudad de Lima se debe al desorden en las vías que generan una gran cantidad de vehículos que circulan en ellas; además, de la mala planificación urbanística representada por zonas comerciales que fueron desarrolladas sin proyección, paraderos y estacionamientos prohibidos que se generan debido a la mala práctica de los conductores, desobediencia hacia las señales de tránsito, entre otros. Estos factores se consideran como los principales causantes de las demoras vehiculares llegando a alcanzar los 100 segundos/vehículo dentro de la intersección analizada. Es por esto que, el presente trabajo evalúa y propone una solución a una de las principales vías en el Cercado de Lima, que presenta los factores descritos anteriormente. Por medio de la microsimulación con el programa Vissim 9, se busca representar el tránsito vehicular con las condiciones mencionadas, además por medio del rediseño geométrico como mejora de propuesta, el análisis que se obtiene reduce hasta el 69.08% de la demora vehicular actual llegando a alcanzar los 31 segundos/vehículo. Asegurando una mejora en la calidad del servicio de la intersección. / Road transport represents one of the main axes for the development and expansion of a country. However, there are several factors why this important resource is not developed with total efficiency. One of these is represented by the high population density in urban centers and its rapid annual growth, giving rise to one of the greatest negative effects in cities that do not put more effort into urban management and planning, traffic congestion. Annually, the increment of the vehicle fleet responds to the demand for a greater number of people who have as one of their main needs to travel from one place to another, for different causes. This generates that the quantity of vehicles increases uncontrollably, making that the quality of the road systems is not the most optimal. One way to measure the quality of transport systems is by their travel times. In Latin America, the average travel time is 64 minutes. Within this statistic is the city of Lima, which has an average travel time of 82 minutes. This makes it one of the cities with the least efficient transportation system in the region. The congestion in the city of Lima is due to the disorder in the roads that generate a great number of vehicles that circulate in them; Besides, of the worst urban planning represented by commercial zones that were developed without projection, prohibited stops and parking that are generated due to the bad practice of the drivers, disobedience towards the traffic signals, among others. These factors are considered as the main causes of vehicle delays, reaching up to 100 seconds/vehicle within the analyzed intersection. Therefore, this paper evaluates and propose a solution to one of the main roads in Cercado de Lima, which presents the factors described above. Employing the microsimulation with the Vissim 9 program, it is sought to represent the vehicular traffic with the observed conditions, besides applying the geometric redesign as proposed improvement, the analysis that is obtained reduces up to 69.08% of the current vehicular delay reaching 31 seconds/vehicle. Ensuring an improvement in the quality of service at the intersection. / Tesis
142

Redesigning the user experience : How Interaction design can be used to improve already existing form-based company services

Lundberg, Victor January 2021 (has links)
This study investigates whether interaction design principles can be used on already existing company services in order to improve the user experience and satisfaction, and how such a process should look like, and what lessons can be learned from it. The study uses an iterative approach where prototypes are created and evaluated to further improve the prototype in the next iteration. To test this a service from the company LeoVegas mobile gaming group called Antiloop is used. Firstly a literature study is conducted to find requirements on how similar services can be designed, then an interview is conducted with employers who use Antiloop in order to find out what can be improved. Then two different prototypes are created and evaluated with the same employees to find out which one is preferred. The results of that evaluation lead to a final prototype that is evaluated together with the existing service through quantitative and qualitative methods, to see whether the new prototype has a better user experience. The results of the final evaluation showed that the new prototype is preferred over the existing version. However, because the test only had 7 participants, it might not be enough to draw a general conclusion. A list of further improvements was also presented.
143

Understanding the Relationships Among Students' Goal Orientations, Self-Efficacy, Anxiety, and Accelerated Academic Success in the Redesign of Developmental Mathematics

Hogan, Kelly Ann 01 January 2016 (has links)
The low success rates of increasing numbers of underprepared students taking developmental mathematics classes 'often minority and economically disadvantaged' are challenging community colleges across the United States. These students, who must start in the lowest levels of precollege mathematics courses, are unlikely to pass the first course and earn a credential. Using a mastery goal orientation theoretical framework, a quantitative, survey research design was used to ascertain any correlations between students' goal orientations, self-efficacy, test anxiety, and success in a new model of learning. Survey data were used to answer 3 research questions: (a) the relationship between success and students' perceptions of self-efficacy, goal orientation, and beliefs about test anxiety; (b) the relationship between demographics and students' perceptions of self-efficacy, goal orientation, and beliefs about test anxiety; and (c) the degree to which students' perceptions and experience predict success. Approximately 500 new students in the course were invited; 36 participated. Spearman's rho, chi-square, and ANOVA were used to answer the research questions. Based on Spearman's rho correlations, there were statistically significant relationships between self-efficacy and success as well as between intrinsic goal orientation and success. However, the sample size limited the generalizability of the findings. Further, there were no significant predictors of success. The white paper developed from this project study is intended to guide the development and expansion of accelerated developmental mathematics to increase academic success, broaden career choices, and improve the long-term economic futures of disadvantaged students enrolling in college.
144

Design kompenzační pomůcky horní končetiny / Design of Upper Limb Assistive Device

Minaříková, Olga January 2012 (has links)
This work deals with a new approach of designing ortho-prosthetic devices in terms of mechanical solution and innovative design. The work was addressed to a specific patient with congenital malformation of upper limbs called phocomelia. A custom-made compensatory aid was made on basis of personal consultations and meetings on specialized workplace; however the aid was built in a way and from parts for other kind of disability. As it turned out, the use of this equipment is associated with many complications, and therefore as a result, this solution proved as unsatisfactory. Nevertheless, thanks to this compensation aid it was possible to specify the problems, to reveal important patterns and highlight the needs for development of entirely new and unique aid designed for patients with phocomelia disability. The work is based on these findings and knowledge acquired from bibliographic search in the field of orthotics, prosthetics, assistive devices and prosthetic equipment. A complete redesign was done with the aim to eliminate all detected problems. The presented result is a unique tool for people with specific congenital disability of upper limbs, with working label 4TE.
145

Modelo de mejora continua que utiliza las herramientas de estandarización de trabajo y teoría de colas aplicado en el canal de ventanilla de una financiera peruana / Continuous improvement model that uses the tools of work study and queuing theory applied in the window channel of a Peruvian finance company

Cutipa Luque, Alexander Anthony, Torrealba Pacheco, Jorge David 07 March 2021 (has links)
Actualmente, existe una demanda creciente en relación al número de reclamos por diversos productos y servicios; y el sector financiero no es ajeno a esto, ya que aproximadamente representa el 45% de reclamos al año en comparación de las demás actividades económica y la gran parte de estos reclamos van ligados a la atención del cliente. En relación a ello, indicadores clave como el tiempo medio de atención y el tiempo medio de espera en cola son vitales para evaluar la calidad del servicio brindado y encontrar puntos de mejora. En este contexto, se ha propuesto un modelo de mejora continua (PDCA) integrado con herramientas como la estandarización de trabajo, que reduce la variabilidad del proceso de atención; y la teoría de colas, que nos permite identificar la distribución correcta de operaciones y servidores que nos garantice un equilibro entre los costos y la capacidad de servicio brindada. Esta aplicación del modelo propuesto tuvo resultados como la reducción de 73% en el tiempo de espera, incremento del nivel de atención en 8% y la reducción del tiempo de operación de 35% aproximadamente. / Nowadays, there is a growing demand for the number of claims for various products and services; and the financial sector is no stranger to this, as it accounts for approximately 45% of claims per year compared to other economic activities and most of these claims are tied to customer service. In this regard, key indicators such as average attention time and average queue waiting time are vital for assessing the quality of service provided and finding points for improvement. In this context, an integrated continuous improvement model (PDCA) is proposed with tools such as work study, which reduces the variability of the care process; and queue theory, which allows us to identify the correct distribution of operations and servers that ensures a balance between costs and the service capacity provided. This application of the proposed model had results such as a 73% reduction in waiting time, an increase in the level of care by 8% and the reduction in operating time of approximately 35%. / Trabajo de investigación
146

Revitalizing a Company Classic : The Story of Revitalizing a Company Classic Using a Practical Method of Design

Hellberg, Mats January 2016 (has links)
The main purpose of this report is to analyze a practical method of design while doing an innovation project connected to a specific armchair. The aim is to re-vitalize the pre-existing product. This project is done within the context of a specific furniture producer. This report describes theories about practical methods of design and how the practical intellect is used in a creative process. It also contains background research about classics. The background research is based on a brief literature review on the subject as well as interviews with professionals within the field of furniture design.  A few factors that can be said to characterize what makes a classic are suggested. The development of a specific armchair is described. Earlier projects where practical methods of design have been used are also described. The practical methods of design used in this project are described. The main method for this is making physical models by hand together with hand sketching.  The design process of developing a new product is described and discussed. As a final result visualizations and a description of a suggestion of how one can re-vitalize the specific armchair are shown. The outcomes and learning from using a practical method of design are discussed. The final suggestion is analyzed according to the factors suggested in the background research to characterize what makes a classic.
147

Robust nonlinear control : from continuous time to sampled-data with aerospace applications. / Commande non linéaire robuste : du temps-continu jusqu’aux systèmes sous échantillonnage avec applications aérospatiales.

Mattei, Giovanni 13 February 2015 (has links)
La thèse porte sur le développement des techniques non linéaires robustes de stabilisation et commande des systèmes avec perturbations de model. D’abord, on introduit les concepts de base de stabilité et stabilisabilité robuste dans le contexte des systèmes non linéaires. Ensuite, on présente une méthodologie de stabilisation par retour d’état en présence d’incertitudes qui ne sont pas dans l’image de la commande («unmatched»). L’approche récursive du «backstepping» permet de compenser les perturbations «unmatched» et de construire une fonction de Lyapunov contrôlée robuste, utilisable pour le calcul ultérieur d’un compensateur des incertitudes dans l’image de la commande («matched»). Le contrôleur obtenu est appelé «recursive Lyapunov redesign». Ensuite, on introduit la technique de stabilisation par «Immersion & Invariance» comme outil pour rendre un donné contrôleur non linéaire, robuste par rapport à dynamiques non modelées. La première technique de contrôle non linéaire robuste proposée est appliquée au projet d’un autopilote pour un missile air-air et au développement d’une loi de commande d’attitude pour un satellite avec appendices flexibles. L’efficacité du «recursive Lyapunov redesign» est mis en évidence dans le deux cas d’étude considérés. En parallèle, on propose une méthode systématique de calcul des termes incertains basée sur un modèle déterministe d’incertitude. La partie finale du travail de thèse est relative à la stabilisation des systèmes sous échantillonnage. En particulier, on reformule, dans le contexte digital, la technique d’Immersion et Invariance. En premier lieu, on propose des solutions constructives en temps continu dans le cas d’une classe spéciale des systèmes en forme triangulaire «feedback form», au moyen de «backstepping» et d’arguments de domination non linéaire. L’implantation numérique est basée sur une loi multi-échelles, dont l’existence est garantie pour la classe des systèmes considérée. Le contrôleur digital assure la propriété d’attractivité et des trajectoires bornées. La loi de commande, calculée par approximation finie d’un développement asymptotique, est validée en simulation de deux exemples académiques et deux systèmes physiques, le pendule inversé sur un chariot et le satellite rigide. / The dissertation deals with the problems of stabilization and control of nonlinear systems with deterministic model uncertainties. First, in the context of uncertain systems analysis, we introduce and explain the basic concepts of robust stability and stabilizability. Then, we propose a method of stabilization via state-feedback in presence of unmatched uncertainties in the dynamics. The recursive backstepping approach allows to compensate the uncertain terms acting outside the control span and to construct a robust control Lyapunov function, which is exploited in the subsequent design of a compensator for the matched uncertainties. The obtained controller is called recursive Lyapunov redesign. Next, we introduce the stabilization technique through Immersion \& Invariance (I\&I) as a tool to improve the robustness of a given nonlinear controller with respect to unmodeled dynamics. The recursive Lyapunov redesign is then applied to the attitude stabilization of a spacecraft with flexible appendages and to the autopilot design of an asymmetric air-to-air missile. Contextually, we develop a systematic method to rapidly evaluate the aerodynamic perturbation terms exploiting the deterministic model of the uncertainty. The effectiveness of the proposed controller is highlighted through several simulations in the second case-study considered. In the final part of the work, the technique of I\& I is reformulated in the digital setting in the case of a special class of systems in feedback form, for which constructive continuous-time solutions exist, by means of backstepping and nonlinear domination arguments. The sampled-data implementation is based on a multi-rate control solution, whose existence is guaranteed for the class of systems considered. The digital controller guarantees, under sampling, the properties of manifold attractivity and trajectory boundedness. The control law, computed by finite approximation of a series expansion, is finally validated through numerical simulations in two academic examples and in two case-studies, namely the cart-pendulum system and the rigid spacecraft.
148

Mutational Analysis and Redesign of Alpha-class Glutathione Transferases for Enhanced Azathioprine Activity

Modén, Olof January 2013 (has links)
Glutathione transferase (GST) A2-2 is the human enzyme most efficient in catalyzing azathioprine activation. Structure-function relationships were sought explaining the higher catalytic efficiency compared to other alpha class GSTs. By screening a DNA shuffling library, five recombined segments were identified that were conserved among the most active mutants. Mutational analysis confirmed the importance of these short segments as their insertion into low-active GSTs introduced higher azathioprine activity. Besides, H-site mutagenesis led to decreased azathioprine activity when the targeted positions belonged to these conserved segments and mainly enhanced activity when other positions were targeted. Hydrophobic residues were preferred in positions 208 and 213. The prodrug azathioprine is today primarily used for maintaining remission in inflammatory bowel disease. Therapy leads to adverse effects for 30 % of the patients and genotyping of the metabolic genes involved can explain some of these incidences. Five genotypes of human A2-2 were characterized and variant A2*E had 3–4-fold higher catalytic efficiency with azathioprine, due to a proline mutated close to the H-site. Faster activation might lead to different metabolite distributions and possibly more adverse effects. Genotyping of GSTs is recommended for further studies. Molecular docking of azathioprine into a modeled structure of A2*E suggested three positions for mutagenesis. The most active mutants had small or polar residues in the mutated positions. Mutant L107G/L108D/F222H displayed a 70-fold improved catalytic efficiency with azathioprine. Determination of its structure by X-ray crystallography showed a widened H-site, suggesting that the transition state could be accommodated in a mode better suited for catalysis. The mutational analysis increased our understanding of the azathioprine activation in alpha class GSTs and highlighted A2*E as one factor possibly behind the adverse drug-effects. A successfully redesigned GST, with 200-fold enhanced catalytic efficiency towards azathioprine compared to the starting point A2*C, might find use in targeted enzyme-prodrug therapies.
149

Redesign av reduktionsutrustning i asselvalsverk inom stålindustri : Ett examensarbete utfört på konstruktionsbyrån BEKAB mot stålindustriföretaget Ovako / Redesign of Reduction Equipment in Assel mill within Steel Industry : A master thesis carried out at the design agency BEKAB towards the steel company Ovako

Andersson, Tommy January 2014 (has links)
Intresset för sömlösa stålrör med stora ytterdiametrar i förhållande till tunna väggtjocklekar har ökat tillsammans med att högre hållfasthet i olika stålsorter tillkommit. Detta gör det möjligt att tillverka lättare, billigare och mer materialeffektiva stålprodukter med samma eller högre hållfasthet som tidigare. Denna nya utvecklingsriktning medför förändringar och utmaningar i en av företaget Ovakos produktionslinor i Rörverk 5 Hofors, vilket de har behov av att samarbeta med maskinkonstruktionsföretaget BEKAB för att utvärdera och utveckla. I Ovakos produktionslina i Rörverk 5 finns en del av ett asselvalsverk som kallas för "förreducerare". Denna del av asselvalsverket ser Ovako ett stort intresse i att utvärdera och utveckla för att bättre anpassas till den nya utvecklingsriktningen.  En känd utmaning hos förreduceraren sen tidigare är att den från början är framtagen för att reducera ner ett kvalitetsproblem hos rörprodukterna som kallas för trattbildning. Projektet fördjupar sig därför inom trattbildning för att bättre förstå grunden till förreducerarens nuvarande design för att därefter genomföra en redesign av förreduceraren. I en nulägesanalys av nuvarande förreducerare framkommer ett flertal olika produktionsutrustningsproblem med tillhörande kvalitetsproblem hos rörprodukterna. Projektet väljer därmed att fokusera på de produktionsutrustningsproblem som ger störst effekt för förreduceraren om de löstes. Detta resulterar i ett nytt produktkoncept av förreduceraren i form av en visuell 3D-CAD-modell med tillhörande hållfasthetsberäkningar och materialoptimering. Studien behandlar ämnen som design, konstruktion, produktutveckling, hållfasthet samt materialoptimering. / The interest in seamless steel tubes with large outside diameters in relation to thin wall thickness has increased along with the strength improvements in various steel grades. This makes it possible to produce lighter, cheaper and more material-efficient steel products with the same or greater strength as before. These new development directions bring changes and challenges in one of the company Ovako's production lines in Tube Mill 5 Hofors, which they need to cooperate with the design agency BEKAB to evaluate and develop. In Ovako's production line in Tube Mill 5 there is a part of an assel mill called "förreducerare". Ovako sees a lot of interest in evaluating and developing this part of the assel mill in order to better adapt to the new development directions. A well-known challenge of the existing reduction equipment is that it was initially developed to reduce a quality issue with the tube products called funnel formation. The project therefore immerses itself into the funnel formation in order to better understand the foundations of the current design of the reduction equipment and to then implement a redesign of the reduction equipment. A situation analysis of the current reduction equipment reveals a number of different production issues with their accompanying quality issues in the tube products. The project thus chooses to focus on the production issues that would have the greatest impact on the reduction equipment if they were resolved. This results in a new product concept of the reduction equipment in the form of a visual 3D-CAD-model with associated strength calculations and material optimization. The study covers topics such as design, engineering, product development, material strength calculations and material optimization.
150

”Kryddan i maten” : Redesign av en kokbok / “Season in food" : Redesign of a cook-book

Skärby, Kim-Richard January 2009 (has links)
The purpose of this project has been to redesign an already existing cook-book. The title of the book (directly translated), “Season in food – the year around with herbs and spices”, contains what the headline imposes: spices, herbs and food. But when the author tries to entwine these parts and communicate it to the reader it is not working all to well due to a poor and inconsistent graphic design. I have followed the theories and values of information design when I redesigned the book layout with the intent to simplify the communication between author and reader. In the progress to make a complete dummie of the book I did multiple literature studies, book analysis, tests and a vast number of drafts. In this report I will describe the whole process from start to finish. It is impossible to explain every aspect of every theory and still make it interesting to read. Instead I try to explain the processes in a more comprehensive way. But details are inevitable and at those times it helps to use the appendix. / Mitt examensarbete har inneburit att göra en redesign på en redan befintlig kokbok. På bokensomslag står det: ”Kryddan i maten – året om med örter och kryddor” och den handlar om just detrubriken antyder: örter, kryddor och mat. Tyvärr har författarens syfte, att knyta samman dessa tvåbitar, gått förlorad i bokens inlaga. Detta beror på en inkonsekvent och ostrukturerad formgivning. Mitt arbete har varit att med hjälp av informationsdesignens regler och teorier göra om och styraupp bokens layout på ett sånt sätt så att informationen på nytt blir lättillgänglig för användaren. Föratt lyckas med det har jag förutom ett gediget skissarbete även utfört utprovningar, litteraturstudiersamt bokanalyser.I denna rapport avhandlar jag hur hela arbetsprocessen sett ut– från bakgrund till färdigt resultat. Rapporten har omöjligt kunnat behandla alla de frågor och tankegångar jag ställts inför utanbehandlar processen på ett mer övergripande sätt. Ibland beskrivs vissa moment detaljerat för attläsaren skall förstå, men genom bilagorna går det att snabbare få en förståelse för vad som menas.

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