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This diploma thesis is focused on the concept of threaded connection of the turbine wheel and shaft. At the beginning are described current welding methods of the turbine wheel and shaft connections as well as methods of the compressor wheel and shaft connections. Four possible concepts were designed and evaluated, and the best concept was chosen. For this concept was calculated tightening torque and concept was evaluated in terms of turbocharger operating conditions.

BACKGROUND: The temporary anchorage devices (TAD) rely on mechanical retention to achieve their function. Following dental implants, the design has not been thoroughly studied. Most of the TADs available in the market are either conical or cylindrical homogenous designs. This study aims to evaluate whether a non-homogeneous design would be able to achieve better biomechanical properties than the current mini- screw designs available on the market. MATERIAL AND METHODS: This is a preliminary study comparing two different 1.5mm TAD designs, the Spider Screw® (Ortho Technology®), and one experimental TAD, the Novel TAD Design (NTD). The two TAD designs were generally described and evaluated following the ANSI/ADA Standard No. 178, then the core diameter / TAD diameter ratio was calculated at 0, 2, 4, and 6mm using the Mitutoyo PH-3500 projection machine in combination with QM-data 200. 10 TADs from each design were inserted in a 30 PCF laminated block from SAW Bone under a 12N axial load, using the Instron 5566A to measure the insertion torques and removal torques. Torque ratios were then calculated. Using the same Instron machine with TADs fully inserted in the artificial bone (2 per design per angle), pull-out tests were performed at angles of 0° / 30° / 60° / 90°. The TADs were loaded up to failure. One-way ANOVA and student's t-test were used for statistical analysis. RESULTS: The Spider Screw® is a conical, self-drilling, self-tapping design with the following general dimensions (d1: 1.5mm ; d2: 0.5mm; d3: 3.4mm; k1: 1mm; k2: 2mm; L1: 9.5mm; L2: 6.5mm; L3: 6.2mm), a 0.6mm pitch, 0.3mm thread depth, asymmetrical triangular threads. NTD, it is a cylindrical-conical, self-tapping design with the following general dimensions (d1: 1.5mm; d2: 0.85mm; d3: 2.5mm; k1: 1mm; k2: 2mm; L1: 9mm; L2: 6mm; L3: 6mm), a 0.5mm pitch, double threads in the first 2mm, a variable thread depth (0-2mm: 0.2mm ; 3-5mm: 0.35mm) and symmetrical rectangular threads. The core to width ratios for the Spider Screw® and NTD were respectively 1 ; 0.64 ; 0.61; 0.54 and 0.7; 0.53; 0.56 and 0.58. Mean insertion torque, removal torque and torque ratio for the Spider Screw and the NTD were respectively (12.78 N.cm / 11.32 N.cm, 0.90 ; 12.73 N.cm / 12.65 N.cm, 0.99 ) Mean pull-out forces at 0°/30°/60° and 90° for the Spider Screw® and the NTD were respectively 124.18 N / 108.59 N / 69.67 N / 84.75 N and 137.72 N / 109.7 N / 64.96 N / 66.78 N. There were no statistically significant differences found. CONCLUSIONS: After evaluating both of the TADs, it is clear that the designs are relatively different. The NTD showed to have a higher torque ratio, and therefore it could mean that the design would be clinically more effective. The NTD showed to perform as good or even slightly better than the Spider Screw® design, but a larger variety of TAD designs is needed to be able to confirm the conclusions of this study. / 2023-03-02T00:00:00Z

Objectives: To investigate differences in the modulus of elasticity, tensile strength, and load at breakage for elastic thread alone and elastic thread with gold chain in combination used in force application of palatally impacted and exposed maxillary canines. Methods: Two groups with n=6 in each were tested. A circular portion of elastic thread was cut, tied and measured to the nearest hundredth of a millimeter and recorded. Five links of a gold chain were cut and an elastic thread was tied to the fifth link opposite the bondable eyelet. The length of the elastic thread and the total apparatus was measured to the hundredth of a millimeter and recorded. An Instron with a ramp speed of 100 mm/min was used for all testing. Results: The addition of the gold chain, as compared to the elastic thread alone, increased the modulus from 8.8 MPa (SD 3.7) to 17.0 MPa (SD 5.03), (p< 0.04) and significantly decreased the maximum tensile stress at breakage from 92.1N (SD 5.0) to 84.1N (SD 1.6), (p<0.004) and the tensile stress at maximum load from 107.8 N (SD 6.7) to 93.8N (SD 4.8), (p<0.002). The stress-strain curve for both groups demonstrated an initial linear behavior followed by non-linear behavior, partially obeying Hooke’s Law, due to the inherent nature of the elastic thread. The addition of the gold chain introduced a rigid element by reducing the of length of the elastic thread by one-half, altering the properties of the assembly. Conclusions: The modulus of elasticity (stiffness) increases and the toughness and resiliency decreases when a gold chain is added to the assembly and compared to elastic thread alone. This could indicate that in the gold chain group, more initial force/strain is delivered to the tooth and there is less stress relaxation over time due to the decrease in the amount of elastic thread. Therefore, the elastic thread alone delivers a more constant and continuous force to the tooth. The use of elastic thread alone may provide a biomechanically more efficient approach to orthodontic movement of impacted and open exposed teeth. / Oral Biology

Field-Programmable Gate Arrays (FPGAs) systems now comprise many processing elements that are processors running software and hardware engines used to accelerate specific functions. To make the programming of such a system simpler, it is easiest to think of a shared-memory environment, much like in current multi-core processor systems. This thesis introduces a novel, shared-memory, cache-coherent infrastructure for heterogeneous systems implemented on FPGAs that can then form the basis of a shared-memory programming model for heterogeneous systems. With simulation results, it is shown that the cache-coherent infrastructure outperforms the infrastructure of Woods [1] with a speedup of 1.10. The thesis explores the various configurations of the cache interconnection network and the benefit of the cache-to-cache cache line data transfer with its impact on main memory access. Finally, the thesis shows the cache-coherent infrastructure has very little overhead when using its cache coherence implementation.

Field-Programmable Gate Arrays (FPGAs) systems now comprise many processing elements that are processors running software and hardware engines used to accelerate specific functions. To make the programming of such a system simpler, it is easiest to think of a shared-memory environment, much like in current multi-core processor systems. This thesis introduces a novel, shared-memory, cache-coherent infrastructure for heterogeneous systems implemented on FPGAs that can then form the basis of a shared-memory programming model for heterogeneous systems. With simulation results, it is shown that the cache-coherent infrastructure outperforms the infrastructure of Woods [1] with a speedup of 1.10. The thesis explores the various configurations of the cache interconnection network and the benefit of the cache-to-cache cache line data transfer with its impact on main memory access. Finally, the thesis shows the cache-coherent infrastructure has very little overhead when using its cache coherence implementation.

This master thesis is a study of anaerobic thread lockers and is done in cooperation withÖhlins Racing AB, which is a Swedish manufacturer of vehicle suspensions.The suspension in vehicles is constantly exposed to high vibration levels and a suspensionunit has several screw- and cylindrical joints. As an extra safety precaution so that thecomponents in the suspension doesn’t fall apart when using the vehicle, an anaerobicthreadlocker is added in these joints. The handling of these threadlockers is not totallyharmless and could lead to allergic reactions, and therefore there are Swedish laws to limit theuse of these. However, new types of anaerobic threadlockers have recently been launched onthe marked that are not considered under this law. The goal of this thesis is to investigate if itwould be possible to change from the today used threadlockers to these new types. A big partof this task has been based on tests of screw- and cylindrical joints. Different materialcombinations of aluminum, anodized aluminum and steel have been tested, as well asparameters such as elevated temperature. The breakloose torque for the thread joints, and theforce required to axially break a cylindrical fitting has been analyzed.Tests were performed with both medium- and high-strength anaerobic threadlockers ofdifferent brands. The results from the screw joint tests with a medium strength threadlockershow that the new health-friendly threadlockers are about as good as the ones used today,except at high temperatures. Considering the high strength threadlockers in aluminum screwjoints, the reference threadlocker showed about 10 – 30 % higher breakloose torque than thehealth-friendly one, depending on the different material combinations. With the steel –aluminum screw joints, the breakloose torque reduced to about half of the aluminum –aluminum breakloose torque values for both types of threadlockers. The results also show thata thicker layer of anodized aluminum gave a higher breakloose torque and that temperaturesof about 85 oC lower the strength with 22 – 29 % compared to the tests in room temperature.In the case with the cylindrical joints, the health friendly ones were weaker than the one usedtoday, but it might still be possible to use them in some products.The conclusions of this thesis are that the health-friendly threadlockers in general are a bitweaker than the ones used today, and that anodized aluminum gives a higher breakloosetorque than both aluminum and steel. It is likely that a change from the threadlockers usedtoday to the new health-friendly ones could be possible in at least some joints. Although moretests have to be done with dynamic loads and oil resistance for example. / Detta examensarbete är en undersökning av anaeroba låsvätskor som utförts i samarbete medÖhlins Racing AB. Öhlins Racing AB är ett svenskt företag som tillverkar högpresterandestötdämpare och fjädring till bland annat motorcyklar och bilar.Stötdämpare i fordon utsätts för mycket höga vibrationsnivåer och för att kunna garanterastötdämparnas kvalitet och livslängd är det av stor vikt att säkerställa att dess komponenterinte lossnar vid användandet. Många komponenter sitter monterade med gängförband ellercylindrisk passning och vid montering tillsätts en låsvätska som en extra säkerhetsåtgärd.Hanteringen av dessa låsvätskor kan leda till hälsoproblem som allergier och luftvägsproblem.Målet med detta arbete är att undersöka om det är möjligt att införa mer arbetsmiljövänligalåsvätskor i Öhlins produkter. Arbetet har bestått av provning med gäng- och cylinderförbanddär olika materialkombinationer av aluminium, anodiserat aluminium och stål, samtparametrar som temperatur har varierats i de olika testuppställningarna. Urpressningskraftenför cylinderförbanden och lossbrytningsmomentet för gängförbanden har analyserats.Tester utfördes med starka och medelstarka låsvätskor av olika fabrikat. Resultaten fråntesterna med gängförband visar att de medelstarka låsvätskorna är mycket likvärdiga, medundantag för högtemperaturtestet där den arbetsmiljövänliga låsvätskan ger sämre resultat.Gällande de starka låsvätskorna i aluminiumförband ger den nu använda låsvätskan 10–30 %högre lossbrytningsmoment än den arbetsmiljövänliga varianten. I förbandet stål – aluminiumvisade det sig att de starka låsvätskornas lossbrytningsmoment över lag låg omkring hälftenjämfört med aluminiumfallet. Resultaten visar också att ett tjockare anodiseringsskikt påaluminiumet ger högre lossbrytningsmoment samt att lossbrytningsmomentet sjunker med 22- 29 % vid temperaturer omkring 85 oC jämfört med i rumstemperatur. I det cylindriska falletkommer de arbetsmiljövänliga låsvätskorna inte upp i samma höga urpressningskraft som denidag använda låsvätskan, men de kan trots detta vara tillräckligt bra för att användas i mångaförband.De slutsatser som kan dras efter detta projekt är att de arbetsmiljövänliga låsvätskornagenerellt sett är lite svagare än den låsvätska som används idag, samt att anodiserataluminium gav högre lossbrytningsmoment än obehandlat aluminium och stål. Det skulleförmodligen vara möjligt att byta ut låsvätskan till arbetsmiljövänlig låsvätska i mångaförband där det inte ställs krav på extremt hög hållfasthet. Det bör dock undersökas närmarehur bland annat dynamiska lastfall och kontakt med olja påverkar låsvätskorna.

In the fast-developing world we are living in, a tech phenomenon known as the Internet of Things (IoT) has taken hold. It has seen a lot of development over the past few decades, and today there are an estimated 30 billion IoT devices active. IoT is a machine-to-machine network that senses the world with the help of sensors. The collected data is then either acted upon by controlling actuators and controllers or displayed in an easily accessible format for the end user. These networks have taken hold in many areas of our societies, such as smart cities, agriculture, industries, smart homes, and even monitoring of our well-being. With such a wide application range, many protocols have been developed for different environments and applications. This report is co-developed with a startup company Devair, which has developed a device to better calibrate and optimize air ventilation systems. A solution that could improve air quality and potentially save money regarding calibration and operational costs. Their device uses Thread as their IoT protocol, a mesh networking protocol that uses the 2.4 GHz frequency band. They have been experiencing connectivity issues with devices being disconnected from the network or not receiving packages. A common problem when using IoT devices, which normally want to use as little transmission power as possible since they are resource-constrained battery-powered devices. Therefore our aim with this work is to research and develop a method of evaluating radio links in a Thread network. We will also look at ways to strengthen these links without changing Devair’s current system. From our findings, we will in this report present a method that extracts both software and hardware metrics for all radio links in a Thread network. This is done to analyze the weak radio links between all devices in the network. The proposed method does not need to establish any DNS server or any other IP addressing service. Instead, each device’s unique RLOC16 identifier is used, which is a feature of the Thread protocol. When weak links have been located using this evaluation method, the report presents two methods to strengthen the weak links. The first which did not yield a favorable outcome is changing to a sub-GHz system compared to the 2.4 GHz system that Thread uses. The sub-GHz system used was a Texas instrument CC1310 using the 868 MHz frequency band, which was compared with the Thread system running on an MGM210PA32JIA SoC. In our tests, we tested both line-of-sight performances as well as signal penetration performance. The tests showed that the Thread system performed substantially better in line-of-sight conditions and marginally better in signal penetration performance. How-ever, we can not conclude that 2.4 GHz systems perform better than 868 MHz systems. For that, further tests need to be done on multiple systems of both frequency bands, and this work should be seen as a comparison between the CC1310 and MGM210PA32JIA systems. The second method utilizes the intrinsic message-hoping feature of a mesh network such as Thread. By placing an intermediary device between two devices that experience a weak radio link, the message can be relayed by the intermediary device that we call a connectivity router. This method improved the link quality by dividing the weak link into two shorter links. When placing the connectivity router, we found that placing it so that the signal can travel the furthest without encountering any obstacles along the way yields the best result. The connectivity router can also be used in such a way to guide the signal around obstacles with a known high attenuation rate. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>

Tématem diplomové práce je revize parní turbíny Mitsubishi a výpočet utahovacích momentů šroubů dělící roviny. Tato práce je rozdělena do několika částí. Úvodní část práce obsahuje seznámení s rozsahem prováděných servisních prací na parních turbínách. Poté je zde samotná revize parní turbíny Mitsubishi. Tato revize je dělena podle jednotlivých komponent turbíny. Poté je zde stanoven seznam nutných oprav a také seznam doporučených oprav pro příští odstávku. V další části je zde shrnut výpočet utěsnění dělicích rovin a to s nebo bez odlehčení. Dále jsou rozebrány nejčastěji používané typy závitů spojovacího materiálu parních turbín. Hlavní částí práce je samotný výpočet utahovacího momentu. Výstupem této práce je poté program pro výpočet utahovacího momentu v programu Excel.

This paper deals with the description of the surface texture measurement methods, describes the devices by which the surface texture can be recorded and describes the parameters that allow the surface texture to be quantified. The practical part deals with the evaluation and comparison of the parameters of metric threads M10 made by cutting and forming by analysis of their cross-sections, then the attention is focused on the analysis of pressure forces and torques which occur during the manufacture and in the last part of the thesis there is an economic evaluation of the cost of manufacturing one piece of cut thread.