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The rolling-sliding dry-wear behaviour of a series of bainitic steels and a standard pearlitic rail steel have been compared over a range of contact stress and creepage conditions applicable to the British Rail network. A rolling-sliding wear machine has been constructed - LEROS - which allows very high contact stresses to be combined with high creepages under well controlled conditions. Materials were tested on LEROS and on an Amsler machine. Limited vibration analyses were carried out on both machines and compared with the frequencies of disc surface periodic undulations. No direct linkage was determined. Despite better standard mechanical properties, the wear resistance of lower carbon bainitic steels was inferior to that of the pearlitic steel. A bainitic steel with the same carbon content as the pearlitic steel wore a little less, but at considerable expense to the pearlitic wheel steel counter-material in the wear couple. The wear resistance of bainitic steels depends upon the volume fraction of hard phase, such as carbide and martensite-austenite phase, for rolling-sliding as well as other types of dry wear loading. Pearlitic steel performs exceptionally well under certain rolling-sliding conditions, such as the majority seen in these tests, since the lamellar microstructure is modified so as to present a greater area fraction of carbide hard phase at the wear surface, a fraction in excess of bulk volume fraction. Recommendations are made for the dry wear applicability of the steels.

During manufacturing of tissue paper, large amounts of energy could be saved with an optimized press nip. In the press nip, water is pressed out of the paper and depending on both machine and paper parameters, the dewatering effect will vary. The dewatering process is however, a complex process which is not fully understood. With the facility to simulate different tissue machine concepts in a lab-testing machine, theoretical models of the dewatering process could be tested and evaluated. Karlstad university has started a three-year project with the purpose of building a lab-test equipment for simulation of pressing of paper, and one of their partners during this project is the company Valmet AB. This master thesis was a part of this three-year project and was carried out in collaboration with Valmet AB. The aim of the master thesis was to determine important parameters affecting the pressing process and the requirements to be considered during the design of the lab-test equipment. The goal was also to develop some concrete concept proposals. During the literature study it was found that the most important parameters of the equipment affecting the result were nip pressure, duration time and process temperature. Paper parameters with the biggest effect on the result were compressibility resistance, flow resistance, ingoing moisture and temperature stability. After discussion with the engineers at Valmet AB, customer requirements of the equipment were determined and these, in combination with the information gathered from the literature study, were used in order to determine the product requirements of the equipment. The most important product requirements turned out to be load capacity, changeable load, process time, distance between upper and lower plate and incorporation of load cells. Several different concept proposals were developed and four of them where evaluated further. The biggest challenge in designing a lab-test equipment for simulation of pressing of paper is the short duration time in combination with high loads, and therefore, all concepts were evaluated according to this as a first step. Plenty of work still needs to be done before any of the generated concepts are finished, but three of them, Three weight, Profile and Electromagnet are seen as potential solutions. / Vid tillverkning av mjukpapper kan stora mängder energi sparas genom att optimera pressnypet. Detta då man i pressnypet kan avlägsna stora mängder vatten från pappret med hjälp av en presskraft, men beroende på både maskin- och pappersparameterar varierar avvattningsförmågan. Avvattningsförloppet är dock en mycket komplicerad process som ännu inte är helt förstådd. Med möjligheten att simulera olika maskinkoncept i en lab-testmaskin kan teoretiska modeller av avvattningsförloppet testas och utvärderas. Karlstads universitet har nyligen startat ett treårigt projekt med syfte att bygga en lab-testmaskin för pressning av papper och en av deras samarbetspartners är företaget Valmet AB. Detta examensarbete var en del av detta treåriga projekt och utfördes i samarbete med Valmet AB. Målet med examensarbetet var att bestämma vilka parametrar som påverkar avvattningen i pressnypet och vilka  krav som måste beaktas under designen av lab-testmaskinen. Målet var även att ta fram konkreta konceptförslag. Från litteraturstudien framkom det att de parametrarna hos utrustningen vilka kommer påverka resultatet mest var nyptryck, varaktighet och processtemperatur. De pappersparametrar vilka har störst betydelse för resultatet visade sig vara kompressabilitetsmotstånd, flödesmotstånd, ingående fukthalt och temperaturstabilitet. Efter diskussion med ingenjörer på Valmet AB kunde kundkraven bestämmas, och dessa i kombination med den sammanställda informationen från litteraturstudien användes för att bestämma produktkraven för utrustningen. De viktigaste produktkraven visade sig vara lastkapaciteten, ändringsbar kraft, processtid, avstånd mellan övre- och nedre plattan, samt att lastceller ska vara inkluderade. Av alla de koncept som togs fram under genereringsarbetet, utvärderades fyra av dem. Den största utmaningen vid design av en lab-testutrustning för simulering av pressning av papper är den korta pressningstiden i kombination med den höga lasten, och därför prioriterades en utvärdering av koncepten utifrån dessa aspekter. Mycket arbete återstår innan ett färdigt koncept står klart, men tre av de utvärderade koncepten, Tre vikter, Profil och Elektromagnet, har potential till att utvecklas till realiserbara utrustningar som möter de uppsatta kraven.

<p>This bachelor thesis includes two different manuals and design of an interface box between a test object and a general test station (computer) with ARINC429 communication.</p><p>There are three different purposes with this project:</p><p>The first is to setup a general test station with ARINC429 communication using a communications card from DDC (DD-42916i3-300) and software from Ampol Technologies (dataSIMS).</p><p>The second is to design a new interface between the test computer and the test object. As well as implementing two components in the equipment.</p><p>The third is to write two separate manuals to guide the users of this equipment. There are two different kinds of users of this equipment, technicians and system engineers. Technicians use the equipment to test and repair flight components. System engineers will implement new components in the equipment.</p><p>The result of this project is a working test station with a new interface and two manuals.</p>

This bachelor thesis includes two different manuals and design of an interface box between a test object and a general test station (computer) with ARINC429 communication. There are three different purposes with this project: The first is to setup a general test station with ARINC429 communication using a communications card from DDC (DD-42916i3-300) and software from Ampol Technologies (dataSIMS). The second is to design a new interface between the test computer and the test object. As well as implementing two components in the equipment. The third is to write two separate manuals to guide the users of this equipment. There are two different kinds of users of this equipment, technicians and system engineers. Technicians use the equipment to test and repair flight components. System engineers will implement new components in the equipment. The result of this project is a working test station with a new interface and two manuals.

Optimum Sensor Localization/Selection in A Diagnostic/Prognostic Architecture Guangfan Zhang 107 Pages Directed by Dr. George J. Vachtsevanos This research addresses the problem of sensor localization/selection for fault diagnostic purposes in Prognostics and Health Management (PHM)/Condition-Based Maintenance (CBM) systems. The performance of PHM/CBM systems relies not only on the diagnostic/prognostic algorithms used, but also on the types, location, and number of sensors selected. Most of the research reported in the area of sensor localization/selection for fault diagnosis focuses on qualitative analysis and lacks a uniform figure of merit. Moreover, sensor localization/selection is mainly studied as an open-loop problem without considering the performance feedback from the on-line diagnostic/prognostic system. In this research, a novel approach for sensor localization/selection is proposed in an integrated diagnostic/prognostic architecture to achieve maximum diagnostic performance. First, a fault detectability metric is defined quantitatively. A novel graph-based approach, the Quantified-Directed Model, is called upon to model fault propagation in complex systems and an appropriate figure-of-merit is defined to maximize fault detectability and minimize the required number of sensors while achieving optimum performance. Secondly, the proposed sensor localization/selection strategy is integrated into a diagnostic/prognostic system architecture while exhibiting attributes of flexibility and scalability. Moreover, the performance is validated and verified in the integrated diagnostic/prognostic architecture, and the performance of the integrated diagnostic/prognostic architecture acts as useful feedback for further optimizing the sensors considered. The approach is tested and validated through a five-tank simulation system. This research has led to the following major contributions: ??generalized methodology for sensor localization/selection for fault diagnostic purposes. ??quantitative definition of fault detection ability of a sensor, a novel Quantified-Directed Model (QDG) method for fault propagation modeling purposes, and a generalized figure of merit to maximize fault detectability and minimize the required number of sensors while achieving optimum diagnostic performance at the system level. ??novel, integrated architecture for a diagnostic/prognostic system. ??lidation of the proposed sensor localization/selection approach in the integrated diagnostic/prognostic architecture.

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Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.

Background: The usage of the Force-Velocity relationship for individualizing training regimes for athletes has increased in popularity. This can be done through measurements of muscle mechanical properties and creating individual force-velocity profiles. To do this, one must use valid and reliable test equipment. These types of equipment are often expensive and impractical, which limits the usage to a small population with the right financial means. Therefore, the purpose of this study was to examine the concurrent validity of the inertial sensor Vmaxpro for measuring muscle mechanical properties. Method: 52 male ice-hockey players (age:17.9 ± 2.2 years, body weight: 77.7 ± 10.6 kg, height: 180.3 ± 6.2 cm) participated in this study and performed two jumps each on four different loading conditions (unloaded, 25, 50 and 75% of BW). The jumps were recorded simultaneously with an inertial sensor and a linear transducer. Three different variables were analyzed: peak velocity (pV), average velocity (avgV) and average power (avgP). Pearson’s correlation coefficient (r), linear regression analysis, Bland-Altman analysis, and standard error of estimate (SEE) was used to examine the concurrent validity. Results: The results showed a strong correlation, agreement and small SEE for pV: r=0.98, bias = -0.12, SEE = 0.08, for avgV: r=0.98 bias = 0.01, SEE = 0.04 and for avgP: r = 0.97, bias = 30.94, SEE = 73.47. Practical application: The results from the present study indicate that the Vmaxpro can be used for assessing muscle mechanical properties. Furthermore, since the Vmaxpro is both cheap and portable, it can potentially expand the usage of test equipment to clubs and associations with limited budgets.