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M. Tech. Industrial Engineering. / Discusses the main objectives of this research are to; analyse the current state of press brakes technology ; develop a press brake concept using the Screw Jack System applying DFM (designing for manufacturability) principles and to fabricate a mini prototype Screw Jack Press Brake.

D. Tech. Industrial Engineering. / Aims to develop new optimized press brake concepts using Reconfigurable Manufacturing System (RMS) principles. The objectives of the research are articulated as follows: Research and identify part/ product families currently being manufactured on existing bending press tools and the respective technologies used. Design new press brake concepts and possible reconfigurations to be incorporated in future bending press tools based on part/ product families. To design the library of modules for the bending press tools based on new concepts and reconfiguration mechanisms formulated. To manufacture prototype(s) based on new concepts and perform experimental tests to evaluate performance of the designs.

Hydrate Ridge is a peanut shape bathymetric high located about 80 km west of Newport, Oregon on the Pacific continental margin, within the Cascadia subduction zone’s accretionary wedge. The ridge's two topographic highs (S. and N. Hydrate Ridge) are characterized by gas vents and seeps that were observed with previous ODP initiatives. In 2008, we acquired a 3D seismic reflection data set using the P-Cable acquisition system to characterize the subsurface fluid migration pathways that feed the seafloor vent at S. Hydrate Ridge. The new high-resolution data reveal a complex 3D structure of localized faulting within the gas hydrate stability zone (GHSZ). We interpret two groups of fault-related migration pathways. The first group is defined by regularly- and widely-spaced (100-150 m) faults that extend greater than 300ms TWT (~ 250 m) below seafloor and coincide with the regional thrust fault orientations of the Oregon margin. The deep extent of these faults makes them potential conduits for deeply sourced methane and may include thermogenic methane, which was found with shallow drilling during ODP Leg 204. As a fluid pathway these faults may complement the previously identified sand-rich, gas-filled stratigraphic horizon, Horizon A, which is a major gas migration pathway to the summit of S. Hydrate Ridge. The second group of faults is characterized by irregularly but closely spaced (~ 50 m), shallow fractures (extending < 160ms TWT below seafloor, ~ 115 m) found almost exclusively in the GHSZ directly beneath the seafloor vent at the summit of S. Hydrate Ridge. These faults form a closely-spaced network of fractures that provide multiple migration pathways for free gas entering the GHSZ to migrate vertically to the seafloor. We speculate that the faults are the product of hydraulic fracturing due to near-lithostatic gas pressures at the base of the GHSZ. These fractures may fill with hydrate and develop a lower permeability, which will lead to a buildup of gas pressures below the GHSZ. This may lead to a vertical propagation of new fractures to release the overpressure, which results in the high concentration of shallow fractures within the GHSZ seen in the 2008 data. / text

Hydraulic conductivity of variably-saturated soils is critical to understanding processes at the land surface. Yet measuring it over an area comparable to the resolution of land-surface models is fraught because of its strong spatial and temporal variations, which render point measurements nearly useless. We derived unsaturated hydraulic conductivity at the horizontal scale of hectometers and the vertical scale of decimeters by analyzing trends in soil moisture measured using the cosmic-ray neutron method. The resulting effective hydraulic conductivity remains close to its value at saturation over approximately half of the saturation range and then plummets. It agrees with the aggregate of 36 point measurements near saturation, but becomes progressively higher at lower water contents; the difference is potentially reconcilable by upscaling of point measurements. This study shows the feasibility of the cosmic-ray method, highlights the importance of measurement scale, and provides a route toward better understanding of land-surface processes.

Air permeability (ka) is a viable alternative to water- and texture-based methods to rapidly map saturated hydraulic conductivity (Ksat). The ability to measure this important hydraulic property without the use of more cumbersome and time-consuming methods may provide a practical approach to generate more complete data to describe hydrologic conditions. This study presents the development of an air permeameter which is suitable for desert soils. The Soil Corer Air Permeameter (SCAP) is compatible with a standard soil corer and employs digital components to measure flowrates under low-pressure gradients to improve accuracy, ease of use, and portability. SCAP allows for the extraction of undisturbed soil samples for laboratory analysis, providing direct comparisons of ka with other soil physical and hydraulic properties. The applicability of a regression equation to estimate Ksat from field-measured ka using SCAP was examined in unburned and burned soils. Ex situ field ka and laboratory Ksat measurements were compared and air to water permeability (ka/kw) ratios were calculated to determine structural changes due to water saturation. The study also characterized changes in permeability due to fire in woodland-chaparral and coniferous soils. For soils that could be extracted with minimal structural changes, results show ka and Ksat measurements for unburned and burned soils were within the 95% confidence intervals of a ka-Ksat regression developed for agricultural soils. However, correlations for in situ ka measurements in some burned soils showed a decrease in accuracy and may be attributed to soil anisotropy. A three-dimensional steady-state finite element air flow model was developed using FEMLAB 3.0A to consider the effects of anisotropy on in situ ka measurements. Results show that anisotropic conditions can introduce an error as high as a factor of 2 especially for air permeameters with high diameter to height (D/H) ratios, however, the error is much smaller than the anisotropy ratio. If anisotropy is important to characterize, it was shown that paired measurements of in situ and ex situ ka can be used to infer the anisotropy ratio.

This master thesis consists of the creation of shock absorber models for percussive rock drills. A model of the rock was also developed. These models were connected to existing models of the rock drill to create a complete simulation of the rock drilling process. When the models had been created the rock model was evaluated by comparison with measured values from lab tests. The verified rock model was then used to evaluate the shock absorber models. Four new shock absorber concepts have been developed. Three of these have been modelled, while the fourth have only been sketched and described. The evaluation of the models showed the following: • Simulations of the single shock absorber don’t correlate to reality very well. The movement is too rapid and poorly damped. • The simulated behaviour of the tandem shock absorber corresponds to reality, but the simulated hydraulic pressures aren’t reliable and neither is the damping. • Simulation of the double shock absorber reflects reality fairly well, although the model of the check valve can be improved. • There are problems with fluttering damper pressures in simulation whenever an accumulator is connected directly to the damper volume. The problem doesn’t exist if there is a line or an orifice with enough losses between the volume and the accumulator. • The feeder system needs to be modelled. / Examensarbetet gick ut på att ta fram simuleringsmodeller av olika dämpare i en bergborrmaskin. Dessutom behövdes en bergmodell som gav korrekta reflexer från berget vid simulering. Dessa modeller kopplades samman med befintliga modeller för att skapa en simulering av hela bergborrningsprocessen. Efter att modeller skapats utvärderades bergmodellen mot mätvärden som uppmätts under prov. Efter att bergmodellen verifierats användes den för att verifiera dämparmodellerna. Fyra dämparkoncept har tagits fram. Tre av dessa har modellerats, medan det fjärde endast har skissats och förklarats. Verifieringen av modellerna visade följande: • Simulering av enkeldämpare stämmer dåligt med verkligheten utan ger för snabba och odämpade rörelser. • Simulering av dubbeldämparen stämmer bra med verkligheten men modellen över backventilen behöver ses över något. • Simulering av tandemdämpare stämmer beteendemässigt men de simulerade trycken är inte tillförlitliga och inte heller dämpningen. • Det finns problem med trycksvängningar vid simulering av modeller där dämpvolymen är direkt ansluten till en ackumulator. Om en strypning eller en ledning med tillräckliga förluster ansluter ackumulator och dämpvolym med varandra märks inte detta problem. • Modell över matningen behöver tas fram.

Railroad bridges and culverts in the United States are often subject to extreme floods, which have been known to washout sections of track and ultimately lead to derailments. The potential for these events is particularly high in the western U.S. due to the lack of data, inadequate radar coverage, and the high spatial and temporal variability of storm events and terrain. In this work, a hydrologic model is developed that is capable of effectively describing the rainfall-runoff relationship of extreme thunderstorms in arid and semi-arid regions. The model was calibrated and validated using data from ten storms at the semi-arid Walnut Gulch Experimental Watershed. A methodology is also proposed for reducing the amount of raingages required to provide acceptable inputs to the hydrologic model, and also determining the most appropriate placement location for these gages. Results show that the model is capable of reproducing peak discharges, peak timings, and total volumes to within 22.1%, 12 min, and 32.8%, respectively. Results of the gage reduction procedure show that a decrease in the amount of raingages used to drive the model results in a disproportionally smaller decrease in model accuracy. Results also indicate that choosing gages using the minimization of correlation approach that is described herein will lead to an increase in model accuracy as opposed to selecting gages on a random basis.

UAB ,,Raseinių žuvininkystės“ tvenkiniai suformuoti 1967-1979 m. Jie išsidėstę trijose vietose: šalia Gabšių gyvenvietės – Raseinių tvenkinių kompleksas, maitinamas Prabaudos upės vandeniu; Upės upelio slėnyje įrengtas Paupio tvenkinių kompleksas aukščiau apie 1 km nuo Paupio gyvenvietės ir tarp Šešuvio ir jo intako Alsos esančioje teritorijoje. Bendras tvenkinių plotas 1042 ha. Tvenkininė žuvininkystė vis labiau pradeda įsitvirtinti tarp kaimo verslų, nors sovietmečiu pastatytuose žuvininkystės tvenkiniuose su mechaniniu vandens kėlimu vandens apykaitai tvenkiniuose palaikyti reikalingos didelės lėšos energetinėms išlaidoms apmokėti, tačiau šis kaimo verslas sukuria nemažai darbo vietų kaime, o žuvininkystės produkcija turi paklausą ne tik Lietuvoje, bet ir užsienyje. Žuvininkystės sukuriama produkcija gerokai sumažėjo lyginant ją su 1990 m., tada buvo išauginta ir sugauta 5800 tonų žuvies, 1998 m. žuvų sugavimas sudarė 1511 tonų, 2001 m. – 2001 tonų ir 2006 – 2225 tonų. Norint sėkmingai plėtoti žuvininkystės verslą, reikalinga ieškoti būdų atnaujinti žuvininkystės įmonių tvenkinių siurblinių energetinę įrangą, remontuoti žuvininkystės tvenkinių hidrotechnikos statinius.Šio darbo tikslas - atlikti UAB ,,Raseinių žuvininkystės“ įmonės tvenkinių HTS techninės būklės tyrimą ir įvertinimą, siekiant gauti ir panaudoti Europos Sąjungos struktūrinių fondų lėšas numatomai renovacijai ir modernizavimui. / The fishponds of the closed joint-stock company “Raseiniai žuvininkystė” were arranged during 1967-1979 years. They are located in the three following places: near the settlement of Gabšiai - the complex of Raseiniai ponds is feeded by the waters of the Prabauda river; in the stream Upe valley the Paupys pond complex is arranged about 1 km upstream the settlement of Paupys and in the territory between the Šešuvis river and its tributary Alsa there is Alsa fishponds . The total fishponds area is 1042 ha. In order to successfully plan the activity of fishery enterprises the evaluation and forward planning of the technical condition of the present ponds’ hydraulic structures is necessary for the reconstruction. The aim of this work was to carry out the investigation and evaluation of the technical state of the hydraulic structures built on the ponds of the closed joint-stock company “Raseiniai žuvininkystė” in order to use the means from the European Union structural funds for the planned renovation and modernization. The object of investigation - the closed joint-stock company “Raseiniai žuvininkystė” situated in the territory of Raseiniai district as well as the evaluation of its economical activity and the state of hydraulic structures built on the ponds. Field investigations of the hydraulic structures built in the complex of Alsa and Paupys ponds were evaluated according to the requirements of the modified Building technical regulations STR 1.12.03:2006 considering the... [to full text]

The thesis research examined localized socio-environmental perceptions related to amplified fresh water requirements for hydraulic fracturing and subsequent flowback disposal activities. These requirements are associated with increasing shale gas development in the Duvernay formation, located within the Kaybob region of West-central Alberta, Canada. Fresh water refers to surface and groundwater with a total dissolved solids concentration of less than 4,000 ppm. Through recourse to a mixed methods approach, combined with triangulation as a method of further validation, the research demonstrates that there exists a public sensitivity related to fresh water use in the Kaybob region. This sensitivity arises from increasing development activities in the Duvernay shale gas formation. The thesis presents conclusions and recommendations whereby industry may address stakeholder concerns, and provides advice for future research.