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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.
31

Konceptutveckling av kabelmaskin för träning med resistans och viktsimulering

Haddad, Robert, Azizi, Aram January 2021 (has links)
På samtliga gymplatser finns alltför många maskiner och redskap idag. De flesta nybörjare har svårt att komma igång med träning, speciellt om dem tränar ensamma. Nybörjare har större chans att överge gymmet än de erfarna. Antalet maskiner och redskap ökar varje år då flera individer börjar hoppa på den nya trenden (fitnessindustrin). Professionella atleter kräver mer än det utbud som finns idag. Resistansträning reducerar skador och assisterar atlet eller nybörjare till att använda muskelgrupper som stärker kroppen utöver träning med vikt Detta examensarbete utgår från att designa en estetisk och funktionell design för en gymprodukt. Dagens samhälle är mer inriktad mot träning jämfört med tidigare. Då teknologi som avanceras blir människan latare. Sedan start av pandemin år 2019 har antalet privatpersoner med ett hemmagym ökat. Produkten som Företag A tillverkar inriktar sig mot företagsgym, privatpersoner samtprofessionella atleter. Examensarbetets primära fokus är att tillsammans med Företag A utveckla en produkt vars syfte är att underlätta träning för marknaden samt öka tillgänglighet och förståelse för träning.  Innan projektet påbörjade skrevs ett konfidentiellt avtal som samtliga parter signerat. Tillsammansmed konfidentiella avtalet skrevs de kravspecifikationer som var viktiga för produkten och dess funktion. Följande frågeställningar ställs för projektet:  Q1: Är den slutliga designen estetisk tilltalande från perspektivet av Företag A? Q2: Hur kan krav för funktioner och estetik kombineras på det mest effektiva sätt? Q3: Hur ska kravspecifikationerna tillämpas för koncepten och delsystemen? Q4: Hur kan koncepten kombineras för det teoretiskt mest effektiva sätt? Med hjälp av litteraturen Produktutveckling, samt hjälp av handledaren underlättades arbetet. Projektet undergick ett par olika faser från att generera koncept, välja ut de viktiga koncepten till att vidareutveckla på dem valda koncepten för ett färdigt resulterande slutkoncept. Detta slutkoncept blir då designen för den färdiga produkten. Slutprodukten resulterade i en sammanfogning av olika koncept för att effektivt integrera design med funktion. Då Företag A ansåg slutdesignen som estetisk tilltalande design så slutfördes arbetet på ett successivt sätt, där alla kravspecifikationer (inom räckvidd) erhölls. Samtliga kravspecifikationer som projektet inte täckte, blir svarade under tillverkningsprocessen som är bortom studenternas uppgifter.Det slutliga konceptet resulterade i en total vikt på 4,731kg, och en preliminär tillverkningskostnad på12 313kr. Resultatet av dessa faktorer överträffade de krav och idealvärden satta för produkten. Den framtida utvecklingen av projektet kräver vidaretestning av funktioner, geometri och sammansättning av komponenter då detta projekt endast framhäver en hypotetisk fungerande produkt. / There are far too many gym machines and equipment’s these days. The majority of the new gym members find it hard to train regularly, especially if they train alone. New members also tend to skip the gym more frequently than that of the experienced and established members. The number of machines and equipment’s used for training purposes increases every year because of the fitness industry increasing in popularity. Professional athletes demand more advanced products because of the increase in competition. Resistance training is the most popular training method because more people look to building muscles rather than functional training. The benefits of resistance training includereduced injuries, builds, and strengthens the muscles. The purpose of this theses is to design a functional and aesthetically pleasing gym product. Today’s generation is more invested in fitness than the past generations. The more technology advances, the lazier humans have become. When the COVID pandemic hit in 2019, the amount of home gym owners reached an all-time high. The product that Company A wants to manufacture is targeted for professional athletes, commercial gyms and for private use. This thesis primary focus is to develop a product with the purpose of facilitate training for the fitness industry, increase availability and build a better understanding for training. This project had a confidential agreement that every participant signed before start. Together with the confidential agreement, the product requirements were written and accepted by all participants. The product requirements include the functional capabilities of the finished product. The following research questions were used to determine the success of the project:  Q1: Is the finished product design esthetically pleasing for Company A? Q2: How can the functional requirements combine with an esthetic design in an effective manner? Q3: How can the product requirements apply for the concept and its part subsystem? Q4: How can the concepts combine in the most effective manner theoretically? This project used most of the help from the supervisor(s) and the “Produktutveckling” literature. The project underwent a few phases as explained in the literature, to generate and select the most useful concept. The chosen concepts were then further developed for a resulting design concept. The developed concept was then chosen as the finished design, by an agreement of the participants. The finished product design resulted in a combination of the different concepts generated in the earlier phases. The reason behind the combination was to include the pros and exclude the cons of each design concept. The project was a success, since Company A approved the design and considered the finished concept as aesthetically pleasing. All of the product requirements that was set were unchanged and included in the finished product. The remaining product requirements that were left unanswered could only be determined by manufacturing and further testing, which is beyond the students signed agreements.
32

Redesign of the Omnideck platform : With respect to DfA and modularity / Omkostruktion av Omnideck plattformenMed hänsyn : Med hänsyn till DfA och modularitet

Brinks, Hanne, Bruins, Mathijs January 2016 (has links)
In this report a product development process is constructed and used to redesign an omnidirectional treadmill, the Omnideck. The current design of the Omnideck platform is designed without regard for assembly. Using modularity and design for assembly theories, incorporated with the product development process, the Omnideck platforms design is improved in respect to assembly time. The original design required 175 labour hours to install. The result is an improved design which requires ten and a half hours to install at a customer. This is achieved by redesigning the Omnideck into individual modules which allow for a faster installation.
33

Shooting Target - Konstruktion : Product Development

Bergkvist, Marcus, Åkerblom, Christopher January 2014 (has links)
The shooting sport is one of the most widespread sports in the world and it is being practice in most countries. Based on their own experiences, in competition - and hobby shooting, the client M4Solutions found a demand and need for a shooting target that is manufactured in Sweden. The purpose of the project has been to develop, with the help of Marcus Walldén, two shooting targets from idea to finished product. These two shooting targets, Plate Rack Target and Dueling Tree, would each be equipped with a mechanical resetting system but will in the future have the ability to be provided with an electronic resetting system. The project from the client was divided into two theses. One of these two, written by Marcus Walldén, focused on the tripod parts and the overall design work for both Plate Rack Target and Dueling Tree. The thesis that is presented in this report have focused on resetting systems, the design of protective plates and other peripherals for both shooting targets. This work has primarily been in CAD environment where design, construction and development has been given free rein. Calculations, test shootings and choice of materials has been made in order to reach the best possible solutions. The thesis resulted in two complete 3D models and two full-scale prototypes of steel.
34

The Effect of Knee Pads on Gait and Comfort

Castagno, Thomas A 26 April 2004 (has links)
The goals of this thesis were: (1) to develop a data acquisition system for measuring gait parameters and (2) to determine the effect of knee pads on gait and comfort. The data acquisition system consisted of a data acquisition card that was inserted in the PC card (PCMCIA) slot of a laptop computer, a knee goniometer, foot switches, and pressure sensors. Various drive circuits were designed to connect the different sensors to the data acquisition card. The gait analysis results showed that the knee pads do not have a significant effect on long range gait correlations calculated from the stride interval. Pressure measurements between the knee pads and the knee showed that a pressure in the range of 0 to 8.31 psi occurred when kneeling. The maximum pressure for the sensor located under the top strap of the knee pad occurred when getting into and out of the kneeling stance. The data acquisition system successfully met the design objectives. The stride interval was recorded and analyzed, and pressures were successfully measured and analyzed.
35

Automatic lithofacies segmentation using the Wavelet Transform Modulus Maxima lines(WTMM) combined with the Detrended Fluctuation Analysis(DFA)

Ouadfeul, Sid-Ali 17 November 2006 (has links) (PDF)
In this paper, we design and develop a new software tool that helps automatic lithofacies segmentation from geological data. Lithofacies is a crucial problem in reservoir characterization, and our study intends to prove that soft computing techniques like Wavelet transform modulus maxima lines (WTMM) and Detrended fluctuation analysis (DFA) approaches allow a geological lithology segmentation from differed well logging. On one hand, WTMM proves to be useful for delimitation of each layer. We based on its sensitivity on the presence of more than one layer, On the other hand, DFA is used to enhance the estimation if the roughness coefficient of each lithology. We use them jointly to segment the lithofacies of boreholes located in the Algerian Sahara. Obtained results are encouraging to publish this method, because the principal benefit is economic.
36

Guidelines for Optimizing Wireline Formation Testing and Downhole Fluid Analysis to Address Fault Transmissivity in the Context of Reservoir Compartment Connectivity

Pfeiffer, Thomas 2010 December 1900 (has links)
Reservoir fluids are rarely found in homogeneous structures having homogeneous properties. The various elements and processes of the petroleum system result in complex fluid distributions and compositions. A sound understanding of these complexities can avoid disappointing results and costly mistakes when designing the completion and production of the reservoir. The earlier these complexities are understood in the exploration phase, the better are the chances of a successful decision making process in the design phase of the project. Assessing reservoir compartment connectivity is of paramount importance for a optimal field development. Recent technological advances in wireline formation testing and sampling provide asset teams with a new methodology to evaluate in situ fluid properties and reservoir connectivity. After a review of the technology of downhole fluid analysis (DFA), the currently available methods of modeling equilibrated fluid gradients are presented. Fluid composition equilibrium is a stationary state where all components have reached zero mass flux. A reservoir model is designed to simulate numerically equilibration processes over geologic timescales at isothermal conditions where diffusion and gravity are the active mechanisms. A variety of initial conditions and reservoir fluid types is considered. Non-equilibrium fluid gradients and their transient behavior as they evolve towards fluid composition equilibrium are the main interest of this study. The results are compared in case studies, that are available in published literature. The modeling methods allow modeling of vertical and lateral fluid gradients. After a discussion of the cases, this thesis gives recommendations on 1) what fluid properties should be assessed and 2) how many data points are needed to reduce the chance of misinterpretation of non-equilibrium gradients in the presence of faults. To make best use DFA data, the property that exhibits the largest gradient needs to be investigated, as it yields the greatest potential to assess connectivity. The shape of the distribution of fluid composition within a compartment is found to be an important part in investigating reservoir connectivity. During data acquisition efforts should be made to acquire enough data points to reveal this shape. In combination with the presented techniques to identify non-equilibrium conditions, this will optimize DFA data acquisition and maximize the value of the data.
37

Cryptanalyse physique de circuits cryptographiques à l'aide de sources LASER

Roscian, Cyril 08 October 2013 (has links) (PDF)
Les circuits cryptographiques, parce qu'ils contiennent des informations confidentielles, font l'objet de manipulations frauduleuses, appelées communément attaques, de la part de personnes mal intentionnées. Plusieurs attaques ont été répertoriées et analysées. L'une des plus efficaces actuellement, appelée cryptanalyse DFA (Differential Fault Analysis), exploite la présence de fautes, injectées volontairement par l'attaquant par exemple à l'aide d'un laser, dans les calculs. Cependant, les modèles de fautes utilisés dans ces attaques sont parfois très restrictifs et conditionnent leur efficacité. Il est donc important de bien connaître quel modèle de faute est pertinent ou réalisable en fonction du circuit cible et du moyen d'injection (dans notre cas le laser). Un première étude portant sur le type de fautes (Bit-set, Bit-reset ou Bit-flip) injectées sur des points mémoires SRAM a mis en évidence la forte dépendance des fautes injectées vis à vis des données manipulées et la quasi inexistence de fautes de type Bit-flip. Ce dernier résultat favorise grandement les attaques de type Safe Error et engendre donc un réel problème de sécurité. La mise en évidence de tels résultats a été possible grâce à des cartographies de sensibilité au laser réalisées sur une cellule SRAM isolée puis sur la mémoire RAM d'un micro-contrôleur 8 bits. Pour confirmer ces résultats expérimentaux, des simulations SPICE d'injection de fautes laser ont été réalisées à partir d'un modèle développé dans l'équipe. Ce modèle prend en compte la topologie de la cible. Des tests ont ensuite été réalisés sur un circuit ASIC implémentant l'algorithme AES. L'analyse des fautes a montré la présence des trois types de fautes mais aussi un faible taux d'injection. En revanche, le taux de répétabilité des fautes était particulièrement élevé. Cela nous a permis d'améliorer une attaque existante et d'obtenir au final une attaque plus efficace que les attaques classiques, nécessitant moins de chiffrements fautés et une analyse des résultats réduite pour retrouver la clef secrète. Enfin, une évaluation des contre-mesures embarquées dans ce circuit a montré leurs inefficacités vis à vis des attaques en fautes par laser. Des pistes d'amélioration ont ensuite été proposées.
38

Forenzní analýza webového prohlížeče / Forensic analysis of a web browser

Bača, Michal January 2015 (has links)
This term project deals with digital forensic analysis of web browsers. The first chapters describe the process of forensic analysis, methodologies and procedures used, and also the issues of analysis of web browsers. In particular, the types of information browser stores and security problems that comes with that. Theoretical and practical procedure for obtaining data from Mozilla Firefox web browser was based on the theoretical foundations described in previous chapters. Common linux tools and application created as part of this thesis are used in process of collecting digital evidence. Digital forensic analysis of web broewser was performed based on suggested procedure.
39

Additiv tillverkad lösning till kontaktorer

Abo saleh, Ahmad Majduldin, N F Adwan, Nouralhuda January 2023 (has links)
Detta examensarbete är på grundnivå som har genomförts under en period av 20 veckor undervåren 2023 och motsvarar 15 högskolepoäng. Projektet har haft som syfte att utveckla ett konceptför en kontaktor och tillämpa additiv tillverkningsteknik som en tillverkningsmetod för konceptet.Uppdragsgivaren för projektet har varit ABB Control Products i Västerås och de har identifieratbehovet av en lämplig lösning för limproblemet i släckpaketet för kontaktorer av storlek nio. Dennuvarande användningen av lim i kontaktorerna ansågs vara ohälsosam och uppfyllde intemiljökraven. Inom ramen för projektet genomfördes en konceptutveckling för att lösa det identifieradeproblemet. Dessutom undersöktes möjligheten att tillämpa additiv tillverkningsteknik ochgenomföra en förenklad kostnadsbedömning för att visa skillnaden i kostnad mellan den nuvarandetillverkningsmetoden och additiv tillverkningsteknik. Produktutvecklingsmetoder användes för attgenomföra projektet, vilket resulterade i ett fungerande teoretiskt koncept. För att sålla ut idéeroch koncept användes en prioriteringsmatris och ett poängsystem. Det resulterande konceptetrepresenteras av CAD-modeller som består av metallplåtar och två delar av det utveckladekonceptet. Konceptet möjliggör en ny design utan användning av lim vid montering. Det har ocksåvisat sig att det är möjligt att ändra tillverkningsmetoden genom att använda additivatillverkningstekniker. Även om prototyperna ännu inte har testats, anses de teoretiska lösningarnavara fungerande.
40

Incremental Fault Analysis: A New Differential Fault Attack on Block Ciphers

Pogue, Trevor January 2019 (has links)
Electronic devices such as phones and computers use cryptography to achieve information security. However, while cryptographic algorithms may be strong theoretically, their physical implementations in hardware can leak unintentional side information as a byproduct of performing their computations. A device's security can be compromised from this leakage through side-channel attacks. Research in hardware security reveals how dangerous these attacks can be and provides security countermeasures. This thesis focuses on a category of side-channel attacks called fault attacks, and contributes a new fault attack method that can compromise a cryptographic device more rapidly than the previous methods when using practical fault injection techniques. We observe that as a circuit is further overclocked, new faults are often superimposed upon previous ones. We analyze the incremental changes rather than the total sum in order to extract more secret information. Unlike many previous methods, ours does not require precise fault injection techniques and requires no knowledge of when the internal state is in a specific algorithmic stage. Results are confirmed experimentally on hardware implementations of AES-128, 192, and 256. / Thesis / Master of Applied Science (MASc)

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