3,795 research outputs found

    The future of shale

    Get PDF
    Master's Project (M.S.) University of Alaska Fairbanks, 2016This project examines the various drivers that led to the U.S. shale oil revolution in order to predict its place in the energy industry going forward and to analyze its effects on Alaska. The shale boom flooded the market with oil causing a dramatic decrease in crude oil prices in late 2014. With this price drop threatening to send Alaska into an economic recession, the future of shale should be of primary concern to all Alaskans as well as other entities that rely heavily on oil revenue. The primary driver leading to the shale revolution is technology. Advances in hydraulic fracturing, horizontal drilling, and 3D seismic mapping made producing shale oil and gas possible for the first time. New technologies like rotary steerable systems and measurements while drilling continue to make shale production more efficient, and technology will likely continue to improve. Infrastructure helps to explain why the shale revolution was mostly an American phenomenon. Many countries with shale formations have political infrastructure too unstable to risk shale investment. Capital infrastructure is a primary strength of the U.S. and also helps to explain why shale development didn't find its way up to Alaska despite having political stability. Financial infrastructure allowed oil companies to receive the funding necessary to quickly bring shale to the market. The final driver explored is crude oil prices. High oil prices helped spark the shale revolution, but with the recent price crash, there is uncertainty about its future. With production costs continually falling due to technology improvements and analysts predicting crude oil prices to stabilize above most project breakeven points, the future of shale looks bright.Introduction -- Shale & Alaska North Slope Crude Oil Prices -- Seeds of its own destruction? Technology -- Hydraulic Fracturing -- History of fracking -- Directional drilling -- History of drilling -- Benefits of directional drilling -- 3D seismic mapping -- Creating a shockwave -- Recording the data -- Interpreting the results -- The birth of a revolution -- Current/future developments -- Rotary steerable system -- Measurements while drilling -- Future developments. Infrastructure -- Political risk -- Financial markets -- Over investment -- Capital infrastructure. Crude prices -- The price crash -- Breakeven prices -- Future prices -- Alaska -- Conclusion -- Bibliography

    Automatic routing module

    Get PDF
    Automatic Routing Module (ARM) is a tool to partially automate Air Launched Cruise Missile (ALCM) routing. For any accessible launch point or target pair, ARM creates flyable routes that, within the fidelity of the models, are optimal in terms of threat avoidance, clobber avoidance, and adherence to vehicle and planning constraints. Although highly algorithmic, ARM is an expert system. Because of the heuristics applied, ARM generated routes closely resemble manually generated routes in routine cases. In more complex cases, ARM's ability to accumulate and assess threat danger in three dimensions and trade that danger off with the probability of ground clobber results in the safest path around or through difficult areas. The tools available prior to ARM did not provide the planner with enough information or present it in such a way that ensured he would select the safest path

    Cost effectiveness analysis of using different monitoring modalities in treating severe traumatic brain injury (CESTBI) in neuro-ICU, HUSM, Kelantan

    Get PDF
    Introduction: There are two schools of thought in practicing neurotrauma monitoring for patients with severe traumatic brain injury (TBI); the application of the baseline neuro-monitoring (BNM) and the use of multiple modalities neurotrauma monitoring (M3) which is very expensive. The answer of which of the two monitoring systems is more eflicient and worth doing should be sought. Objective: To determine the cost effectiveness analysis between BNM and M3 monitoring modalities in the management of severe TBI. Methodology: Sixty-two patients with severe TBI admitted to Neuro-ICU, USM who fulfilled the predetermined criteria were selected using systematic random sampling. The macro and micro costing were performed on each of patient. Barthel Index was used to measure physical performance as an outcome six months after discharge. The analyses used were the Independent t- test, ANCOVA, and Repeated Measure ANOVA. Results: The mean total equipment cost of M3 was significantly higher at p = 0.049 (mean difference of RM23.74) after controlling other variables. The mean difference in Barthel Index after six months was significance between the two groups (p = 0.031), patients that were treated with M3 had higher score 163.7 (SD 30.03)J compared to those who were treated with BNM 146.83 (SD 30.36)]. However, the cost-effectiveness ratio of using M3 was significantly lowered (p=O.031) with a mean of RM476.29 was needed to increase a unit improvement in mean Barthel Index compared to RM629.12 if we used BNM. Conclusion: Although M3 is more costly, the outcome of patients treated with M3 was better than that of BNM. Therefore we can conclude that the used of multiple neuro-monitoring was more cost effective than the use of only baseline neuro-monitoring in treating severe traumatic brain injury

    Discrete event simulation tool for analysis of qualitative models of continuous processing systems

    Get PDF
    An artificial intelligence design and qualitative modeling tool is disclosed for creating computer models and simulating continuous activities, functions, and/or behavior using developed discrete event techniques. Conveniently, the tool is organized in four modules: library design module, model construction module, simulation module, and experimentation and analysis. The library design module supports the building of library knowledge including component classes and elements pertinent to a particular domain of continuous activities, functions, and behavior being modeled. The continuous behavior is defined discretely with respect to invocation statements, effect statements, and time delays. The functionality of the components is defined in terms of variable cluster instances, independent processes, and modes, further defined in terms of mode transition processes and mode dependent processes. Model construction utilizes the hierarchy of libraries and connects them with appropriate relations. The simulation executes a specialized initialization routine and executes events in a manner that includes selective inherency of characteristics through a time and event schema until the event queue in the simulator is emptied. The experimentation and analysis module supports analysis through the generation of appropriate log files and graphics developments and includes the ability of log file comparisons

    Development and application of operational techniques for the inventory and monitoring of resources and uses for the Texas coastal zone. Volume 1: Text

    Get PDF
    The author has identified the following significant results. Image interpretation and computer-assisted techniques were developed to analyze LANDSAT scenes in support of resource inventory and monitoring requirements for the Texas coastal region. Land cover and land use maps, at a scale of 1:125,000 for the image interpretation product and 1:24,000 for the computer-assisted product, were generated covering four Texas coastal test sites. Classification schemes which parallel national systems were developed for each procedure, including 23 classes for image interpretation technique and 13 classes for the computer-assisted technique. Results indicate that LANDSAT-derived land cover and land use maps can be successfully applied to a variety of planning and management activities on the Texas coast. Computer-derived land/water maps can be used with tide gage data to assess shoreline boundaries for management purposes

    Electron-hole interactions in coupled InAs-GaSb quantum dots based on nanowire crystal phase templates

    Full text link
    We report growth and characterization of a coupled quantum dot structure that utilizes nanowire templates for selective epitaxy of radial heterostructures. The starting point is a zinc blende InAs nanowire with thin segments of wurtzite structure. These segments have dual roles: they act as tunnel barriers for electron transport in the InAs core, and they also locally suppress growth of a GaSb shell, resulting in coaxial InAs-GaSb quantum dots with integrated electrical probes. The parallel quantum dot structure hosts spatially separated electrons and holes that interact due to the type-II broken gap of InAs-GaSb heterojunctions. The Coulomb blockade in the electron and hole transport is studied, and periodic interactions of electrons and holes are observed and can be reproduced by modeling. Distorted Coulomb diamonds indicate voltage-induced ground-state transitions, possibly a result of changes in the spatial distribution of holes in the thin GaSb shell.Comment: 8 pages, 7 figure

    Single-electron transport in InAs nanowire quantum dots formed by crystal phase engineering

    Full text link
    We report electrical characterization of quantum dots formed by introducing pairs of thin wurtzite (WZ) segments in zinc blende (ZB) InAs nanowires. Regular Coulomb oscillations are observed over a wide gate voltage span, indicating that WZ segments create significant barriers for electron transport. We find a direct correlation of transport properties with quantum dot length and corresponding growth time of the enclosed ZB segment. The correlation is made possible by using a method to extract lengths of nanowire crystal phase segments directly from scanning electron microscopy images, and with support from transmission electron microscope images of typical nanowires. From experiments on controlled filling of nearly empty dots with electrons, up to the point where Coulomb oscillations can no longer be resolved, we estimate a lower bound for the ZB-WZ conduction-band offset of 95 meV.Comment: 9 pages 9 figure
    • …
    corecore