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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.
171

Almohadish

Gomez Ezpinoza, Carolyn, Llenque Correa, Lizeth Rosmery, Pando Tinoco, Henry Lucio, Sánchez Tananta, Juan Manuel, Santa María Ortiz, Josselyn Jerycka 04 December 2020 (has links)
En la siguiente tesis se explica la viabilidad del negocio de almohadillas terapéuticas que contienen semillas aromatizantes, hojas de plantas nativas peruanas. Estas hojas tienen propiedades relajantes y aliviadoras de tensión muscular, que permitirán reducir los dolores musculares causados por la tensión. Los segmentos por abarcar en este proyecto son los niveles socioeconómicos A y B de Lima Metropolitana cuyo rango de edad se encuentre entre 20 y 40 años. Nuestra idea de negocio consiste en la venta de una almohadilla  terapéutica, la venta se realizará a través de los canales de Facebook e Instagram. Nuestro producto será entregado en una bolsa ecológica el cual contendrá nuestra almohadilla terapéutica a un precio de 50 soles.  En cuanto a lo desarrollado en nuestro plan de negocio se ha obtenido los siguientes resultados: Respecto a nuestro flujo de caja anual proyectado por lo próximos 3 años se obtiene que Almohadish si está siendo rentable. En cuanto a nuestro margen neto tenemos un crecimiento del 9% del año 2 al año 3, debido a que nuestras ventas aumentan más de lo que aumentan nuestros gastos en Marketing y RRSS. Finalmente, en cuanto a los indicadores financieros tenemos que nuestro VAN es positivo, cabe recalcar que la industria tomada para el beta es Healthcare products. La TIR, nos muestra que esperamos que nuestro proyecto rinda mínimo un 10%, sin embargo como nuestro proyecto es rentable,  nos está rindiendo un 48% es decir más de lo esperado, por último tenemos como resultado que en 2 años aprox. se recuperará la inversión. / The following thesis explains the viability of the business of therapeutic pads containing flavoring seeds, leaves of native Peruvian plants. These leaves have relaxing and muscle tension relieving properties, which will reduce muscle aches and pains caused by tension.  The segments to be covered in this project are the socioeconomic levels A and B of Metropolitan Lima whose age range is between 20 and 40 years. Our business idea consists of the sale of a therapeutic pad, the sale will be made through the channels of Facebook and Instagram. Our product will be delivered in an ecological bag which will contain our therapeutic pad at a price of 50 soles. As for the development of our business plan, we have obtained the following results: With respect to our annual cash flow projected for the next 3 years, we have obtained that Almohadish is profitable. As for our net margin, we have a 9% growth from year 2 to year 3, due to the fact that our sales are increasing more than our Marketing and HR expenses. Finally, as far as financial indicators are concerned, our NPV is positive; it is worth noting that the industry taken into account for the beta is Healthcare products. The IRR shows that we expect our project to yield at least 10%; however, since our project is profitable, it is yielding 48%, which is more than expected. / Trabajo de investigación
172

Parametric Design & an Approach to Weight Optimization of a Metallic and Carbon Fiber Wing

Joe, John 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In a multifidelity structural design process, depending on the required analysis, different levels of structural models are needed. Within the aerospace design, analysis and optimization community, there is an increasing demand for automatic generation of parametric feature tree (build recipe) attributed multidisciplinary models. Currently, this is mainly done by creating separate models for different disciplines such as mid-surface model for aeroelasticity, outer-mold line for aerodynamics and CFD, and built-up element model for structural analysis. Since all of these models are built independently, any changes in design parameters require updates on all the models which is inefficient, time-consuming and prone to deficiencies. In this research, Engineering Sketch Pad (ESP) is used to create attribution and maintain consistency between structural models with different fidelity levels. It provides the user with the ability to interact with a configuration by building and/or modifying the design parameters and feature tree that define the configuration. ESP is based an open-source constructive solid modeler, named OpenCSM, which is built upon the OpenCASCADE geometry kernel and the EGADS geometry generation system. The use of OpenCSM as part of the AFRL’s CAPS project on Computational Aircraft Prototype Syntheses for automatic commercial and fighter jet models is demonstrated. The rapid generation of parametric aircraft structural models proposed and developed in this work will benefit the aerospace industry with coming up with efficient, fast and robust multidisciplinary design standardization of aircraft structures. Metallic aircraft wings are usually not optimized to their fullest potential due to shortage of development time. With roughly \$1000 worth of potential fuel savings per pound of weight reduction over the operational life of an aircraft, airlines are trying to minimize the weight of aircraft structures. A stiffness based strategy is used to map the nodal data of the lower-order fidelity structural models onto the higher-order ones. A simple multi-fidelity analysis process for a parametric wing is used to demonstrate the advantage of the approach. The loads on the wing are applied from a stick model as is done in the industry. C program is created to connect the parametric design software ESP, analysis software Nastran, load file and design configuration file in CSV format. This problem gets compounded when it comes to optimization of composite wings. In this study, a multi-level optimization strategy to optimize the weight of a composite transport aircraft wing is proposed. The part is assumed to initially have some arbitrary number of composite super plies. Super plies are a concept consisting of a set of plies all arranged in the same direction. The thickness and orientation angles of the super plies are optimized. Then, each ply undergoes topometry optimization to obtain the areas of each super ply taking the least load so that it could be cut and removed. Each of the super plies are then optimized for the thickness and orientation angles of the sub plies. The work presented on this paper is part of a project done for Air Force Research Laboratory (AFRL) connecting the parametric geometry modeler (ESP) with the finite element solver (Nastran).
173

Fästanordningar för textila återbrukbara sanitetsskydd : En kvalitativ och kvantitativ studie med syfte att utveckla fästanordningar för återbrukbara sanitetsskydd / Fasteners for textile reusable sanitary pads : A qualitative and quantitative study with the aim of developing fasteners for reusable sanitary pads

Nilsson, Amanda, Olsson, Anna January 2023 (has links)
För att öka användandet av återbrukbara sanitetsskydd under menstruation inkontinensproblematik och som trosskydd i både utvecklade- och utvecklingsländer krävs det att sanitetsskyddet förutom att uppfylla sitt syfte, även sitter på plats och känns tryggt. För att uppnå detta krävs en komfortabel fästanordning som håller skyddet på plats. För att jobba mot en mer hållbar värld genom reducering av engångsartiklar i plast och mot ett samhälle utan mensfattigdom kan återbrukbara sanitetsskydd vara ett steg i rätt riktning. Branschstandard för återbrukbara sanitetsskydd är idag en binda med en tryckknapp som fästanordning. Tidigare studier framhäver dock en viss problematik med att fästanordningen inte håller sanitetsskyddet på plats utan att skyddet åker åt sidan under användning. För att ta fram en optimal fästanordning för återbrukbara sanitetsskydd, har tre stycken nya fästanordningar tagits fram i denna studie. Dessa fästanordningar var en silikonbeläggning applicerad under skyddet, ett ruggat polyestertyg applicerad på skyddets undersida och två stycken silikonband fastsydda i underbyxans gren för sanitetsskyddet att fästas mellan. Dessa tre kom sedermera att jämföras med den redan etablerade fästanordningen med tryckknapp. Studien baserades på en kvalitativ undersökning som genomfördes av sex kvinnor mellan 25-63 år som förde logg om sina upplevelser av de fyra olika fästanordningarna. Den kvalitativa studien fördes parallellt med en kvantitativ studie i form av ett tvätt-, kraft- och friktionstest för att mäta och jämföra de olika fästanordningarnas hållbarhet i relation till tvätt och användning. Det kvalitativa testet visade på att fästanordningen med tryckknapp och fästanordningen med silikonband integrerade i underbyxa var mest komfortabla och kändes säkrast. Från de kvantitativa testerna presterade silikonbanden integrerade i underbyxa bäst och bekräftar den kvalitativa undersökningen. Däremot riktades kritik från respondenterna kring långsiktigt användande, hygien, utseende och hållbarhet mot fästanordningen med silikonband. Efter resultatanalys kan slutsatsen dras att känslan av psykisk komfort är viktig och att känslan av trygghet infinner sig när sanitetsskyddet är ordentligt fast i underbyxan. Med kritiken i beaktning samt tvättestets resultat som visade på en antydan till slitage av polyesterns kanter, kan en kombination med tryckknapp och silikonbeläggning rent hypotetiskt vara en optimal fästanordning. / In order to encourage the use of reusable sanitary pads for: incontinence problems, panty liners and menstruation in both developed and developing countries alike, a sanitary pad which feels secure and sits in place, whilst also maintaining its functionality, is required. To achieve this a convenient fastening device that holds the sanitary pad in place is necessary. This in turn, helps create a more sustainable planet by reducing single-use plastic items, whilst simultaneously reducing menstrual poverty. Today, the industry standard for reusable sanitary protection is a pad with a press stud as its fastening device. However, previous studies highlight a particular problem with this pad, in which the fastening device does not hold the sanitary protection properly in place. Instead the press stud design has been shown to consistently move to the side for the user, therefore causing discomfort. In order to develop an optimal fastening device for reusable sanitary pads, this study developed three new fasteners: a sanitary pad with a silicone coating applied underneath the pad, a sanitary pad with a coarse polyester fabric on its underside, and a pair of regular underpants with silicon bands sewn in to allow for a pocket for the sanitary pad. These three designs have been developed to compare with the already established press stud fastener. The study was based on a qualitative survey of six women between the ages of 25-63 who kept a log of their experiences testing the four different fasteners that were applied to a reusable pad. The qualitative study was carried out in parallel with a quantitative study in the form of a: washing, force and friction test to measure and compare the durability of the various fasteners in relation to washing and use. The qualitative test showed that the fastener with a press stud and the fastener with silicone bands sewn into the underpants, were the most comfortable and felt the most secure. From the quantitative tests, the silicone bands sewn into the underpants performed best and confirmed the qualitative investigation. After analyzing the results, a conclusion can be drawn that the feeling of psychological comfort is of upmost importance for users. Based on the qualitative and quantitative results, silicone bands integrated into underpants performed best for its purpose. On the other hand, criticism from the respondents regarding long-term use, hygiene, aesthetics and durability was directed at this fastening device. Taking the criticism into account and the results of the washing test where signs of wear and tear were shown on the polyester fabric, a combination with a press stud and silicone coating could hypothetically be the optimal fastening device.
174

Skin Health Monitoring Sensor on Textiles : Incorporation of pH Responsive Dyes on Polyethylene and Polypropylene Nonwovens

Biswas, Tuser January 2016 (has links)
Incontinence diapers or disposable absorbent pads provide essential help to people having such a physical difficulty. However, during prolonged used of these products in daily life, the skin inside pad area may get fragile and damaged which are difficult to recover in old ages. Therefore a skin friendly sensor can be added to the inner layer of pad that would monitor the skin condition and signal any abnormalities to the wearer. Smart materials which can change color upon variation of skin pH were incorporated with synthetic nonwoven layers of the pad. Among various incorporation methods of these materials, ‘sol-gel’ coating technique was found to be successfulfor applications on optical sensor and on fewother fabric types. Thus ‘sol-gel’ method with modified recipe for different dye and chemical combinations were experimented in this project.Several developed samples showed color change (e.g. yellow to red) that can be easily detected by wearers’ eyes.Additionally, the methods and materials involved showed no adverse effect on health and environment. Thus this study succeeds to provide with a mean for skin health monitor based on nonwoven textiles by incorporation of color changing materials.
175

Developing Methods for Prediction and Reduction of Springback using a Practical Method to Estimate E-Modulus

Katre, Aanandita Ramakant 07 December 2017 (has links)
No description available.
176

J/Ψ Production Via χ<sub>c</sub> Decays in Fixed Target Proton-nucleus Collisions

Goulart, Dickson C. January 2004 (has links)
No description available.
177

Acoustic Prediction Methods for Rocket Flame Deflector Design

RANOW, FREDRIK January 2021 (has links)
The aim of the project behind this report is to gain an understanding for the design criteria of launch pad flame deflectors used for launching rockets. This report presents an overview of the underlying phenomena, and then tackles the issue of estimating noise levels that come about during lift-off. Semi-empirical methods are used to accomplish this, and the same basic processes as those presented in a 1971 NASA report are used. The underlying assumptions and approximations used in this report are analysed, and a number of modifications are suggested. The results of these modifications are presented in comparison to the original model as well as data taken from the Ares I-X launch. It is found that the suggested methodology tends to overpredict where the SP-8072 method underpredicts, and that additional considerations regarding launch pad structure and water attenuation will need to be included for a more detailed understanding. Furthermore, the topic of acoustic reflectivity is investigated. It is demonstrated that this aspect is heavily dependent on the dimensions of the flame duct immediately downstream of the nozzle, and that further development is warranted. / Målet med detta projekt är att öka förståelsen för flamdeflektorer och vad som avgör utformningen av dessa. Rapporten presenterar en översikt av de fenomen och mekanismer som alstrar ljud, och fokuserar sedan på att beskriva hur dessa ljudnivåer uppskattas. Semi-empiriska metoder används, och de processer som presenteras i en NASA-rapport från 1971 tillämpas. De antaganden och approximationer som används i denna analyseras, och en rad ändringar föreslås. Resultaten från dessa ändringar presenteras tillsammans med den oförändrade modellen tillsammans med uppmätt data från uppskjutningen av Ares I-X. Den föreslagna modellen visar sig överuppskatta där den oförändrade tenderar att underuppskatta. Ytterligare aspekter gällande uppskjutningsplattformens geometri samt den dämpande effekten vatten har behöver iakttas för en mer detaljerad modell. Akustisk reflektivitet och dess ljudbidrag undersöks. Det visas att denna aspekt beror starkt på dimensionerna för avgaskanalen direkt nedströms från dysan. Det finns därmed anledning för vidareutveckling av denna modell.
178

A new paradigm for disc-pad interface models in friction brake system

Qiu, L., Qi, Hong Sheng, Wood, Alastair S. January 2014 (has links)
In this paper a 2D coupled thermal-stress finite element model is established and used to predict thermal phenomena at the disc-pad interface of a disc brake system. The importance of certain critical settings and parameters for the 2D FE model has been identified (such as, a limited degree of freedom for a brake pad in place of accepted practice that considers uniform contact), here a non-uniform pressure distribution resulting from friction bending moment effects due to the introduction of a pivot point. These parameters affect the distributions of both interface temperature and pressure. The simulation results show that when the interface conductance h is 10^6 W/m^2K or higher, the interface temperature distribution is no longer sensitive to friction bending moment effects. However, when h is 30000 W/m^2K or lower, the interface temperature distribution and heat partition ratio are significantly affected by the setting used for the rotational degree of freedom of the pad. The simulation results provide a useful reference for a better design of a disc brake system for different applications.
179

Novos ataques de canal secundário a dispositivos de entrada manual de dados confidenciais. / New side-channel attacks on devices for manual input of sensitive data.

Faria, Gerson de Souza 09 December 2016 (has links)
Esta tese apresenta três novos ataques a equipamentos de pagamento eletrônico que possuem teclado mecânico, conhecidos como \"PIN pads\". Mostramos de três formas distintas como tais equipamentos possuem vulnerabilidades de segurança na camada física que permitem o vazamento do PIN (Personal Identification Number) quando o mesmo é digitado. Demonstramos experimentalmente que é possível inferir com elevada taxa de acerto (100% em um dos ataques) a senha digitada, de forma não-invasiva. Os ataques desenvolvidos são baseados na introdução de sensores nos próprios equipamentos ou em seu ambiente de operação: acelerômetros para análise de vibração, microfones para análise acústica e células de carga para medição de forças do pressionamento. Devido à massificação no uso de sensores por dispositivos de consumo, o roubo de informação por meios não convencionais é atividade crescente. Os resultados dos ataques de baixo custo realizados expõem sérias deficiências no processo de certificação de segurança de tais equipamentos. / This thesis presents three new attacks on electronic payment equipment having mechanical keypads, known as \"PIN pads\". We show in three different ways how they have security vulnerabilities at the physical layer allowing the leak of the PIN (Personal Identification Number) when it is entered. We experimentally demonstrated that it is possible to infer with high success rate (100% in one of the attacks) the password entered on the device, in a non-invasive way. The attacks are based on the placement of sensors inside the equipment itself or in its operating environment: accelerometers for doing vibration analysis, microphones for acoustic analysis and load cells for measuring the pressing force. Due to massive deployment of sensors in consumer devices, information theft by unconventional means is increasing. The results of the low-cost attacks here developed expose serious shortcomings in the process of security certification of such equipment.
180

Novos ataques de canal secundário a dispositivos de entrada manual de dados confidenciais. / New side-channel attacks on devices for manual input of sensitive data.

Gerson de Souza Faria 09 December 2016 (has links)
Esta tese apresenta três novos ataques a equipamentos de pagamento eletrônico que possuem teclado mecânico, conhecidos como \"PIN pads\". Mostramos de três formas distintas como tais equipamentos possuem vulnerabilidades de segurança na camada física que permitem o vazamento do PIN (Personal Identification Number) quando o mesmo é digitado. Demonstramos experimentalmente que é possível inferir com elevada taxa de acerto (100% em um dos ataques) a senha digitada, de forma não-invasiva. Os ataques desenvolvidos são baseados na introdução de sensores nos próprios equipamentos ou em seu ambiente de operação: acelerômetros para análise de vibração, microfones para análise acústica e células de carga para medição de forças do pressionamento. Devido à massificação no uso de sensores por dispositivos de consumo, o roubo de informação por meios não convencionais é atividade crescente. Os resultados dos ataques de baixo custo realizados expõem sérias deficiências no processo de certificação de segurança de tais equipamentos. / This thesis presents three new attacks on electronic payment equipment having mechanical keypads, known as \"PIN pads\". We show in three different ways how they have security vulnerabilities at the physical layer allowing the leak of the PIN (Personal Identification Number) when it is entered. We experimentally demonstrated that it is possible to infer with high success rate (100% in one of the attacks) the password entered on the device, in a non-invasive way. The attacks are based on the placement of sensors inside the equipment itself or in its operating environment: accelerometers for doing vibration analysis, microphones for acoustic analysis and load cells for measuring the pressing force. Due to massive deployment of sensors in consumer devices, information theft by unconventional means is increasing. The results of the low-cost attacks here developed expose serious shortcomings in the process of security certification of such equipment.

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