Rainfall-induced landslides that change into debris flows and travel large distances are one of the treacherous natural calamities that can occur in mountainous areas, particularly in Nepal’s mountains. Debris flow was the second highest cause of human death in Nepal after epidemics between 1971 and 2016. Because debris flow is common in mountainous regions, its prediction and remedial measures through land use plans are important factors to consider for saving lives and properties. The spatial distribution of the initial landslides that change into debris flow, on a watershed scale, is still an important area of study in this mountainous region to develop essential land use plan. In this research, hydrologic, slope stability and Flow-R models are applied in GIS modeling to locate potential landslide and debris flow areas for a given threshold rainfall in a mountainous watershed-Kulekhani, Nepal. Soil samples from 73 locations within the watershed and a geotechnical investigation on one old landslide area were considered to determine the Soil Water Characteristics Curve (SWCC), friction angle, cohesion, and infiltration characteristics of the subsurface soils in the study area. This information is applied in an unsaturated slope stability model to find unstable locations in the study watershed in a GIS environment. The model is tested on a recorded 24-hour rainfall of 540 mm in the watershed, and potential landslide locations are obtained. The validation results show that there is a good agreement between the predicted and mapped landslides. For debris flow run out, Flow-R model, which has the capability to analyze debris flow inundation with limited input information, and the model software is readily available in the public domain, was chosen for further analysis. Two recent debris flow events and the study watershed are taken as case studies to identify the appropriate algorithms of Flow-R for runout analysis of the study areas. Landslide-triggering threshold rainfall frequency is related to the frequency of landslides and the debris flow hazard in these mountains. The above validated models are applied in a GIS environment to locate potential debris flow areas in expected threshold rainfall. Rainfall records from 1980 to 2013 are computed for one- to seven-day cumulative annual maximum rainfall. The probable rainfalls for 1 in 10 to 1 in 200 years return periods are identified. The anticipated probable rainfalls are modeled in the GIS environment to identify the factor of safety of mountain slopes for landslide susceptibility in the study watershed. The Flow-R model with user-defined landslide-susceptible areas was chosen for debris flow runout analysis. A relation between the frequency of rainfall and landslide-induced debris flow hazard area is derived for return periods of 25, 50, 100, and 200 years. Also, the debris flow hazard results from the analysis are compared with a known event in the watershed and found to agree. This developed method can be applied to anticipated landslide and landslide-induced debris flow from the live rainfall record to warn hazard-prone communities for saving lives and regulating hazardous transportation corridors in these mountains. In addition to this, this methodology will be a useful tool to help policy makers create appropriate land use plans.

Miniaturized devices are the key producing next-generation microelectro-mechanical products. The applications extend to many fields that demand high-level tolerances from microproducts and component functional and structural integrity. Silicon-based products are limited because silicon is brittle. Products can be made from other engineering materials and need to be machined in microscale. This research deals with predicting microtool failure by studying spindle runout and tool deflection effects on the tool, and by measuring the cutting force that would fail the tool during microend-milling. End-milling was performed using a tungsten carbide (Ø1.016 mm dia., 2 flute) tool on SS-316L material. Tool runout measured using a laser was found to be less than 1 µm and tool deflection at 25000 rpm was 20 µm. Finite element analysis (FEA) predicts tool failure due to static bending for a deflection greater than 99% of tool diameter. Threshold values of chipload and cutting force resulting in tool failure were found using workdone by tool. Threshold values to predict tool failure were suggested for axial depth of cut in between 17.25% - 34.5% of cutter length. For a chipload greater than 20% of cutter diameter, the microtool fails instantly for any radial depth of cut.

Fault tolerant control can accommodate the component faults in a control system such as sensors, actuators, plants, etc. This dissertation presents two fault tolerant control schemes to accommodate the failures of power amplifiers and sensors in a magnetic suspension system. The homopolar magnetic bearings are biased by permanent magnets to reduce the energy consumption. One control scheme is to adjust system parameters by swapping current distribution matrices for magnetic bearings and weighting gain matrices for sensor arrays, but maintain the MIMO-based control law invariant before and after the faults. Current distribution matrices are evaluated based on the set of poles (power amplifier plus coil) that have failed and the requirements for uncoupled force/voltage control, linearity, and specified force/voltage gains to be unaffected by the failure. Weighting gain matrices are evaluated based on the set of sensors that have failed and the requirements for uncoupling x1 and x2 sensing, runout reduction, and voltage/displacement gains to be unaffected by the failure. The other control scheme is to adjust the feedback gains on-line or off-line, but the current distribution matrices are invariant before and after the faults. Simulation results have demonstrated the fault tolerant operation by these two control schemes.

The work presented herein describes the production of hot strip with special attention to the runout table. Because of its high capital and operating costs, a new principle in conveying the strip using an air cushion and a new cooling system for strip cooling have been proposed. Information given here is nearly all from available literature and the author's own experience with Hot Strip Mill production problems. To support the idea of using an air cushion for strip conveying, experimental equipment was designed and built which confirmed the feasibility of the method. A new cooling system was also proposed to meet the ever increasing requirements for better mechanical properties of hot strip. Runout table design application may serve as a guideline in designing new Hot Strip Mill runout table. / Thesis / Master of Engineering (ME)

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<p>The demands for ride comfort quality in today's long haulage trucks are constantly growing. A part of the ride comfort problems are represented by internal vibrations caused by rotating mechanical parts. This thesis work focus on the vibrations generated from radial runout on the wheels. These long haulage trucks travel long distances on smooth highways, with a constant speed of 90 km/h resulting in a 7 Hz oscillation. This frequency creates vibrations in the cab, which can be found annoying. To help out with the vibration diagnosis when a truck enters a mechanical workshop, this work studies methods for radial runout detection using the wheel speed sensors.</p><p>The main idea is to represent the varying radius signal with a sinusoid, where the calculations are based on Fourier series. The estimated radial runout value is then the amplitude of the sinusoid. In addition to the detection part, the work also present results regarding how the relative phase difference between two wheels with radial runout effects the lateral motion of the cab.</p><p>This thesis work was performed at Scania CV AB in Södertälje, Sweden and all measurements have been full scale experiments on real trucks.</p>

The demands for ride comfort quality in today's long haulage trucks are constantly growing. A part of the ride comfort problems are represented by internal vibrations caused by rotating mechanical parts. This thesis work focus on the vibrations generated from radial runout on the wheels. These long haulage trucks travel long distances on smooth highways, with a constant speed of 90 km/h resulting in a 7 Hz oscillation. This frequency creates vibrations in the cab, which can be found annoying. To help out with the vibration diagnosis when a truck enters a mechanical workshop, this work studies methods for radial runout detection using the wheel speed sensors. The main idea is to represent the varying radius signal with a sinusoid, where the calculations are based on Fourier series. The estimated radial runout value is then the amplitude of the sinusoid. In addition to the detection part, the work also present results regarding how the relative phase difference between two wheels with radial runout effects the lateral motion of the cab. This thesis work was performed at Scania CV AB in Södertälje, Sweden and all measurements have been full scale experiments on real trucks.

Variations in vehicle noise, vibration and harshness (NVH) response from one vehicle to the next can have significant impact on an automotive company’s profile and profitability. The warranty claims due to excessive NVH response end up costing the manufacturers a large sum of money each year. In addition, the OEM will suffer a larger financial loss due to the poor perception of quality and customer dissatisfaction with their products due to the unacceptable NVH response. Therefore, measures must be taken to ensure less warranty claims and higher levels of customer satisfaction. This research focuses on aspects of design variations that are costly or difficult to be avoided in the design process such as variations with rubber parts and variations due to rotating components. Vibrations induced at the tire/wheel assembly due to variations in the radial and tangential forces and radial runout are responsible for the driverelt vibrations that can lead to a large number of warranty claims. The purpose of this research is to improve the process of determining and analyzing vibration sources in the tire/wheel assembly in order to benefit the automotive manufacturer during the development and manufacturing phases. This research identifies the relationship between non-uniformity forces of the tire/wheel assemblies and the driverelt vibrations during typical highway driving speeds. The contribution from each assembly location is analyzed and sensitivities are determined. A Monte Carlo process is used to predict numerous non-uniformity properties that are statistically representative of the assembly properties that can be expected at the manufacturing plant. The Monte Carlo produced non-uniformity properties are combined with the sensitivities to predict driverelt vibrations that can be expected from vehicles leaving the manufacturing plant. This process provides the tools to determine an acceptable level of non-uniformities based on targets for interior vibration levels or determine if the vehicle sensitivities to non-uniformities need to be improved.

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