• Magnetometer and direct-current resistivity studies in Alaska

      Joesting, Henry R. (University of Alaska Mineral Industry Research Laboratory, 1941)
      During the past year and a half, the territorial Department of Mines in Alaska has conducted a modest experimental program for the purpose of determining the extent to which magnetic and resistivity methods can be used in interior Alaska in connection with prospecting, mining and geological studies. Since little information is available concerning previous work, and since conditions differ considerably from those in most other regions, it was considered advisable to make a general study of the possibilities and limitation[s] of the two methods, rather than a detailed study of any single problem.
    • Major impediments to a feasibility study in the case of Smith Bay development

      Hullavarad, Nilima V.; Perkins, Robert A.; Hulsey, J. Leroy; Connor, Billy G. (2017-05)
      The State of Alaska is one of the energy-producing states which rely on revenue from energy extraction, but faces several challenges, especially significant fluctuations in revenue generated by taxes. In the past, oil production from established oil fields on state land yielded sufficient tax revenue. For new sources of oil, oil company owners must make a decision about developing the prospects based on a feasibility study which produces preliminary design, cost estimates, project schedule, including many permits and other uncertainties, financing, and tax credits. When this study is done, the decision can be made to begin development. This paper considers the feasibility studies on main obstacles in the development path of Smith Bay. The evaluation of major tasks needed for a feasibility study, uncertainty and obstacles, combined with our estimation of the time period required for the oil fields to produce oil, led to an estimate of the time before tax money will be provided to the state.
    • Managing Dust on Unpaved Roads and Airports

      Barnes, David; Connor, Billy (Alaska University Transportation Center, Alaska Department of Transportation and Public Facilities, 2014)
    • Managing Dust on Unpaved Roads and Airports

      Barnes, David; Connor, Billy (Alaska University Transportation Center, 2014-10)
      Fugitive dust emanating from vehicle traffic on unpaved roads and runways can have significant impacts on safety, health, quality of life, and the cost of maintenance. Managing dust provides a means of reducing these impacts. Shearing forces created at the interface between the surface and vehicle tires produce dust on unpaved surfaces. The dust produced becomes airborne as a result of turbulence created by moving vehicles. Once airborne, different monitoring techniques can be used to assess the amount of fugitive dust produced and to measure the effectiveness of dust management strategies. Communities can manage dust by properly constructing and maintaining the unpaved surface, reducing vehicle speed on roads, and with the proper use of dust palliatives. The proper gradation of aggregate, the right profile, and good drainage are all necessary for reducing fugitive dust from unpaved roads and runways. Moreover, reducing vehicle speed on unpaved roads can dramatically reduce the amount of fugitive dust and result in longer periods between maintenance events. Several different types of palliatives are available for both managing dust on unpaved roads and runways. The choice of palliative is dependent on aggregate gradation, traffic amounts, climate, and location (remote or accessible).
    • Managing Water Resources for Alaska's Development: Proceedings

      Aldrich, James W. (University of Alaska, Institute of Water Resources, 1983-11)
    • Mapping and predicting the ionospheric effects to communication systems in northern aurora areas using the global positioning system

      Wang, Lingyun (2002-08)
      This thesis focuses on mapping and predicting ionospheric effects to communication systems in northern high latitude areas using GPS (Global Positioning System). The monitoring of ionospheric scintillation and TEC (Total Electron Content) over Fairbanks, Alaska has been achieved by using the GSV4004 GPS Ionospheric Scintillation and TEC Monitor (GISTM), which has been installed on the roof of Duckering Building at UAF since September 2001. The algorithm of acquiring equivalent vertical TEC above Fairbanks from various satellite measurements is given in detail. Both an empirical ionosphere model, IRI, and a physics-based ionosphere model, PIM, are used to verify the TEC real field measurement. Another signal estimation method, BP neural network, is used to forecast the TEC short-term variation, which can give better performance than the other two. The relationships among TEC, amplitude scintillation and phase scintillation are analyzed. Multipath effects and the impact to GPS performance from ionospheric scintillation are discussed. Lastly the TEC and scintillation index mapping around Fairbanks is presented.
    • Mapping the Wolverine Way: Identifying Conservation Corridors and Transboundary Linkages in the Canadian Crown of the Continent Region

      Clevenger, Anthony P. (2019-09-13)
      The Canadian Crown of the Continent (CCoC) is one of three zones where wolverines can move between Canada and the US, providing the last links for recruitment and ultimately gene flow to the highly fragmented population in the US Rocky Mountains. However, a combination of rapidly expanding logging, energy development and motorized recreation, along with a growing road network, threatens to fragment and diminish connections in this critical transboundary linkage between the US and Canada. This report summarizes a project to complete a 3-year sampling effort in the CCoC, which in turn completed a larger 6-year effort over a vast area of the central and southern Canadian Rockies. In 2016, the research team surveyed the last unsampled portion of the Alberta Rockies (south of Kananaskis Country to Highway 3) in addition to a substantial portion of the East Kootenay region of the British Columbia Rockies (BC; >9000 km2). This follow-up effort allowed the team to complete an entire ecoregion-wide wolverine survey in the Canadian Rockies ecoregion, from the US-Canadian border north to Banff and Yoho National Parks. From this data, researchers created density estimates and occupancy models of wolverine distribution and its multiple landscape stressors across an extensive and complex region of the Great Northern Landscape. The report summarizes research findings and makes recommendations regarding management strategies.
    • The market for insulation in Alaska and feasibility of the regional manufacture of insulating materials

      Haring, R.C.; Beasley, C.A. (University of Alaska Mineral Industry Research Laboratory, 1965)
      This investigation was undertaken jointly by the Mineral Industry Research Laboratory and the Institute of Business, Economic and Government Research at the University of Alaska. It is one of a continuing series of studies concerning the market and utilization rate for selected structural materials within Alaska. The overall objective of these studies is to identify opportunities for the regional manufacture of selected building products. In this manner, this limited study of insulation markets complements more extensive previous studies concerning Alaskan cement and clay products, markets and manufacturing feasibility.
    • The market potential for Alaskan clay products

      Beasley, C.A. (University of Alaska Mineral Industry Research Laboratory (MIRL), 1965)
      This study was originally proposed to the Alaska Department of Economic Development and Planning as part of a continuing effort by the Mineral Industry Research Lab of the University of Alaska to strengthen and diversity the mineral industry of the state.
    • Mass transfer study on CO₂ penetration through methane hydrates using CO₂ vapor and a CO₂ nucleated micro-emulsion

      White, Aaron N. (2003-12)
      Gas hydrates are solid inclusion compounds that are made up of ice and large amounts of guest gas molecules. Due to their abundance in nature and the ability to entrap large amounts of natural gas, progress towards tapping this energy resource is on the forefront of research. Much research on the kinetics of formation and decomposition needs to be completed. This study was comprised of the identification of CH₄ and CO₂ through their characteristic Peak Raman shifts, the determination of the mass transfer rates of CO₂ through pre-formed methane hydrate, and an experimental injectant using a dissociated CO₂ micro-emulsion to help destabilize the CH₄ hydrate zone. Identification experiments showed that characteristic peak locations were instrument dependent and that O-H stretch analysis could help in the determination of the phase gas was in. Mass transfer rates were obtained for CO₂ penetration through methane hydrates by a headspace swap in an associated free gas zone. Experimental temperatures of the hydrate zone were 0, 2.5, and 4.5°C. Results indicate that CO₂ can penetrate into CH₄ hydrate zone by dissociating the CH4 from a hydrate phase and stabilizing the mixed CO₂-CH₄ hydrates. The process is slow in the magnitude of 10⁻⁸ meters per second.
    • Material characterization of Alaskan asphalt mixtures containing reclaimed asphalt pavement (RAP)

      Kemp, Beaux M.; Liu, Jenny; Saboundjian, Steve; Schnabel, William (2016-12)
      Recycled asphalt pavement (RAP) material has been combined with hot-mix asphalt (HMA) paving for several decades to reduce construction costs and environmental impacts. In Alaska, the HMA specification allows up to 15% RAP for Type-II A mixes (typically used in wearing courses) and 25% for Type II-B mixes (used in wearing or base courses). Highway construction projects statewide are expected to see an increase in the use of RAP in future mix designs. Pavement engineers use mechanistic procedures (e.g. Alaska Flexible Pavement Design software and Mechanistic-Empirical Pavement Design Guide) to develop flexible pavement design alternatives. These procedures require material engineering properties as an input source. Consequently, it is essential to properly establish the engineering properties of HMA mixtures containing RAP. In order to characterize Alaskan HMA materials containing RAP, this study evaluated 11 HMA mixtures comprised of three typical Alaskan asphalt binders (PG 52-28, PG 58-34 and PG 52-40) containing 0%, 25% and 35% RAP that were either produced in the lab or a hot-plant (i.e. collected from actual paving projects in Alaska). Various binder and mix properties were determined including; true high binder grades, complex shear modulus (G*) and phase angle (delta) at high performance temperatures, as well as asphalt mixture performance tests (AMPT); dynamic modulus (E*) and flow number (FN). The original (h-based) and the modified (G*-based) Witczak (E*) predictive models were evaluated for these mixtures based on job mix formulae availability for use in mechanistic design procedures. It was found that the incorporation of RAP into Alaskan HMA increased E* and FN of the mixtures, which indicates that the addition of RAP increased the stiffness and rutting resistance of the mixtures tested. A local calibration of the Witczak predictive models may be required for increased accuracy of E* predictions. For Alaskan conditions, a savings of $13.60/ton of mix was estimated for a 25% RAP mix. For an 18-feet wide one lane-mile of HMA mat, it is estimated to have a 21% savings in the 25% RAP mix compared to the conventional virgin (no RAP) mix.
    • Maximum weight lifting prediction considering dynamic joint strength

      Rana, G M Rahid uz zaman; Xiang, Yujiang; Chen, Cheng-fu; Peterson, Rorik (2018-05)
      This thesis describes an efficient optimization method for predicting the maximum lifting weight considering dynamic joint strength in symmetric box lifting using a skeletal model. Dynamic joint strength is modeled as a three-dimensional function of joint angle and joint angular velocity based on experimentally obtained joint strength data. The function is further formulated as the joint torque limit constraint in an inverse dynamics optimization formulation to predict the lifting motion. In the proposed optimization formulation, external load is treated as design variables along with joint angle profiles, which are represented by control points of B-spline curves. By using this new formulation, dynamic lifting motion and strategy can be predicted for a symmetric maximum weight box lifting task with given initial and final box locations. Results show that incorporating dynamic strength is critical in predicting the lifting motion in extreme lifting conditions. The prediction outputs in joint space are incorporated in OpenSim software to find out muscles force and activity during the movement. Electromyography data are collected for a regular weight lifting to validate the integration process between the predictive model (joint model) and OpenSim model (muscle model). The proposed algorithm and analysis method based on motion prediction and OpenSim can be further developed as a useful ergonomic tool to protect workers from injury in manual material handling.
    • Measurement of effective diffusion on andesite rock, Amchitka Island, Alaska

      Raghupatruni, Srinivas Rao (2004-05)
      Between 1965 and 1971 three nuclear weapon tests were conducted on Amchitka Island, Alaska. Currently research is being conducted to understand the possible movement of radionuclides through the Island subsurface into the marine environment so that a monitoring system can be developed. The possibility of radionuclide diffusion into matrix rock surrounding facture pathways needs to be better understood. This thesis presents ongoing research with the goal of determining the effective diffusion coefficients for andesite rock found in the Island subsurface. These studies are being conducted in a bench scale reactor consisting of two chambers separated by a sliced rock core obtained from the Island. The increase in conservative tracer over time is measured in the receiving chamber. The effective diffusion coefficients are then determined by applying these results to a solution to Fick's Second Law. Results from these studies will be used in the development of a long term monitoring program for the island.
    • Measurement of electron density in the earth's magnetosphere using discrete whistler mode echoes observed on the image satellite

      Li, Jingbo (2004-12)
      In this thesis, a new whistler mode sounding method has been developed to measure magnetospheric electron density using the RPI instrument on the IMAGE satellite. During the 2000-2002 period, RPI frequently recorded discrete whistler mode (WM) echoes in the ~10-400 kHz frequency range when IMAGE was at low altitudes (<7000 km) in the inner plasmasphere or near its perigee in the southern hemisphere. Most discrete cases were observed in the wintertime in the southern hemisphere during the local morning or nighttime. Ray tracing simulations indicate that the discrete echoes may result from reflections of RPI signals from the earth-ionosphere boundary. By comparing the measured and calculated time dispersion of discrete WM echoes, it is possible to determine the plasma density along the ray path as well as the nonducted or ducted modes of propagation. The ray tracing simulations were carried out for 8 cases observed in the year 2002 when discrete echoes were accompanied by Z mode echoes. The 8 cases were chosen to cover the maximum and minimum local electron densities, which varied from ~300 - 4000 el/cc at the satellite location as measured from Z mode echoes. The simulations showed that the electron densities at the F2 layer peak (~250 km altitude) varied from 1 x 10⁵ to 7 X 10⁵ el/ cc for all the cases. The extrapolated electron density of the calculations at ~4000 km altitude varied from ~200 - 2000 el/cc (L <4) and ~60 - 1000 el/cc (L> 4). The extrapolated electron density at ~8000 km altitude ranged from ~100 -1000 el/cc (L <4) and from 20 - 60 el/cc (L> 4). These results are in general consistent with previous observations of plasma density in the low altitude magnetosphere. The ray tracing simulation results also indicate that in each of the 8 cases studied whistler mode waves incident on the Earth-ionosphere boundary have incident angles that fall within the transmission cone angle and hence can be observed at the Earth's surface.
    • Measurement of gas-water relative permeabilities in hydrate systems

      Jaiswal, Namit J.; Dandekar, Abhijit Y.; Chukwu, Godwin A.; Khataniar, Santanu; Patil, Shirish L. (2004-08)
      Gas hydrates are considered to be an alternative energy resource of the future, as they exist in enormous quantities in permafrost and the offshore environment. One of the primary mechanisms involved in hydrate decomposition in porous media is the gas-water two-phase flow in the formations. Despite their importance, these functions are poorly known due to the lack of fundamental understanding of gas-water flows and the difficulty of direct measurements for hydrate systems. As part of a major Alaska gas hydrate project, an experimental apparatus was designed and developed for forming gas hydrates in the laboratory and performing gas-water relative permeability experiments. In this study effective permeability and relative permeability across hydrate saturated consolidated Oklahoma 100 mesh sand and Anadarko field samples were measured. The results suggest that the relative permeability inferred from unsteady state core floods is a lumped parameter which not only includes hydrate saturation but also the effects of dissociation instabilities caused by fluid flow, fine migration and local compaction in porous media at low temperature. Furthermore, these properties are significantly altered by nature of hydrate distribution throughout the specimen, location within the pores, and concentration at specific locations.
    • Measurement of Temperature and Soil Properties for Finite Element Model Verification

      Darrow, Margaret M. (Alaska University Transportation Center, Alaska Department of Transportation and Public Facilities, 2010)
    • Mechanistic studies for improved understanding of low salinity waterflooding based enhanced oil recovery and potential application to the Alaskan North Slope reservoirs

      Chavan, Mukul N.; Dandekar, Abhijit; Khataniar, Santanu; Patil, Shirish (2015-05)
      Improvement in the recovery of oil by low or reduced salinity water has been reported by many researchers. However, a consistent mechanistic explanation behind low salinity waterflood has not yet emerged. A thorough literature review was conducted that pertains to low salinity water based enhanced oil recovery and preliminary screening criteria were proposed which may help in narrowing down the responsible mechanisms and identifying suitable candidates for low salinity waterflood. Altogether nine different variables, such as clays, oil characteristics, salinity ranges etc. were considered in developing the screening criteria. With the exception of some tests on standard Berea sandstone cores, all other experimental studies were carried out on representative Alaska North Slope (ANS) reservoir core samples and oil and brine samples. Experimental studies involved a direct visualization of the release of crude oil from the clay surface with low salinity waterflood as observed through a simple substrate type test. Amott type spontaneous displacement tests were performed to quantitatively determine the effect of low salinity water using core materials containing different types of clays. Two sets of low salinity water coreflooding experiments were conducted in the tertiary recovery mode; first using dead oil and the second using recombined oil at pseudo reservoir conditions to examine the potential in improving oil recovery. Oil recoveries were also compared with continuous injection vs slug-wise injection of low salinity water. Finally, surface level investigation was performed using an optical microscope to visually analyze the impact of low salinity water on core samples. All the experiments performed with low salinity water on Alaska North Slope (ANS) reservoir core samples consistently showed anywhere between a 3-30 % increase in oil production with the use of low salinity brine. The literature review identified wettability alteration, cation exchange capacity, clay type and clay content as some of the dominant mechanisms influencing low salinity waterflooding.
    • Meta-analysis of hydraulic fracture conductivity data

      Rahman, Mohammed Rashnur; Awoleke, Obadare O.; Goddard, Scott; Ahmadi, Mohabbat (2017-12)
      Previous empirical models of propped fracture conductivity are based either on data sourced from single investigations or on data not in the public domain. In this work, statistically rigorous models of propped fracture conductivity are developed using a database of fracture conductivity experiments reported in technical literature over the last 40 years. The database contains the results from about 2700 experimental runs. Propped fracture conductivity is the dependent variable and proppant types, mesh size, proppant concentration, formation hardness, closure stress, formation temperature, and polymer concentration are the independent variables. The mother database is partitioned into subsets; that is different databases with each daughter database having complete information in relation to the dependent and independent variables. As a result, the number of independent variables included in the daughter databases varied from three to six. Seventy percent of the data was used to develop the models while 30% of the data was used to validate them. First, fixed effect models were developed using regression analysis. Afterwards, three, four and five factor models were compared for two types of proppant: sand and ceramic proppant. The five factor model appeared to be the most prominent one. The analysis was further carried out using five factors of these two types of proppant. Mixed effect modeling was employed because of the disparate sources of the data and also the temporal diversity of the dataset. The mixed effect model appeared to be the better than the fixed effect model while compared the error terms. Also, because the mother database contained some missing values, two statistical imputation approaches were employed to predict the missing values which are categorical imputation and multiple imputation using chained equations. Imputations are employed because it is speculated that a model developed using a large number of data points should provide better predictions. Generally, the mean squared error (MSE) is less in the mixed effect model for sand and in the categorical imputation model for ceramic proppant. But, to be more precise on the performance of the models, model predictions were compared with an existing propped fracture conductivity model and different case histories published in literature. Subsequently, the models of this research can be arranged in order of predictive performance: multiple imputation model, mixed effect model, fixed effect/categorical imputation model. The results also indicate that mesh size, closure stress, formation hardness, and proppant concentration significantly affect fracture conductivity from a statistical point of view. Formation temperature and polymer concentration affect conductivity negatively but they were not statistically significant. Engineers will have access to a propped fracture conductivity database based on experiments reported over the past 40 years in technical literature. Engineers can use the models developed based on this database to generate statistical distributions of propped fracture conductivity for a variety of proppant characteristics and formation conditions. The models presented here are based on data from experimental investigations in different laboratories thereby reducing the bias that may be present in single laboratory investigations.
    • Metal hydride storage of hydrogen for remote energy systems

      Kenny, Tristan Daniel (2002-05)
      As the world transitions towards more efficient and environmentally responsible energy systems there is a growing need for improved energy storage methods. For hydrogen based energy systems one method being examined involves the storage of hydrogen in a reversible metal hydride. These systems provide high storage density and low parasitic loss making them a good candidate for use in remote energy systems. In order to evaluate metal hydrides for possible use in conjuction with integrated fuel cell reformer systems a test bench was constructed and a steady state energy balance performed. This energy balance was designed to determine the heating and cooling loads associated with loading and unloading the hydride bed and give a verification of theoretical estimates. Using the test system values of 28.6 and 28.4 kJ / mol were found for the test alloys. The theoretical results were 28.6 and 28.0 kJ / mol respectively.