Blank, Matt; Dockery, David; Pohl, Christina (2019-03)
      The purpose of this research was to evaluate how characteristics of hydraulic structures, such as slope or size, used at crossings over waterways relate to operation and maintenance (O&M) effort, fish passage, and stream function. Data on O&M concerns, fish passage concerns, and crossing characteristics were collected from 45 road-stream crossings in Prudhoe Bay, Alaska, during lower and higher water periods in both 2014 and 2015 (four events total). Logistic regression and generalized mixed models were used to examine relationships between O&M effort (response) and five explanatory variables. For all data from all years combined, there were no observable associations among O&M and culvert type or constriction ratio. However, lower constriction ratios were observed for sites with O&M needs in the June 2014 data set. The proportion of sites with both fish passage and O&M concerns was 0.52; comparatively, the proportion of sites with no fish passage concern but with O&M concern was 0.35.
    • Sludge Production and Disposal for Small Cold Climate Bio-Treatment Plants

      Tilsworth, Timothy (University of Alaska, Institute of Water Resources, 1972-12)
      Ultimate disposal of wastewater sludge has long been a problem which to a large degree has been ignored. Haney (1971) stated that: "Until process sludge can be handled with minimum environmental impact, we cannot claim to have a viable wastewater treatment process". The relationship of sludge disposal to total treatment processes is emphasized by the fact that sludge handling and disposal represents up to 50 percent of the total treatment capital and operating costs (Burd, 1968). Processing of wastewater sludge will, no doubt, receive increased attention in the future because of environmental concerns for our air, land and water. The present technology for processing wastewater treatment plant sludge is well established and includes conditioning, dewatering, and disposal. Many of these processes are highly sophisticated and relatively expensive. Most of the more advanced processes are unsuitable for small wastewater treatment facilities in Alaska.
    • Small scale implementation of a robotic urban search and rescue network

      Kibler, Steven G. (2012-05)
      With the advancement of robotics technologies, it is now possible to use robots for high risk jobs that have historically been accomplished by humans. One such example is the use of robots for Urban Search and Rescue (USR): finding chemical spills, fires, or human survivors in disaster areas. With the ability to include inexpensive wireless transceivers, it is possible to network numerous robots as part of a swarm that can explore an area much more expeditiously than a single robot can. With the inclusion of wireless capabilities comes the necessity to create a protocol for the communication between robots. Also necessary is the creation of an exploration protocol that allows the network of robots to explore such a building or search area in as little time as possible yet as accurately as possible. This thesis covers the development of such a network of robots, starting with the hardware/software co-design, the individual robots' control mechanisms, and their mapping and communications protocols.
    • Smart FRP Composite Sandwich Bridge Decks in Cold Regions

      Hulsey, J. Leroy; Qiao, Pizhong; Fan, Wei; McLean, David (Alaska University Transportation Center, 2011)
    • Snow Survey Results for the Central Alaskan Arctic, Arctic Circle to Arctic Ocean: Spring 2013

      Stuefer, Sveta; Homan, Joel; Gieck, Robert; Youcha, Emily (2014-02)
      Many remote areas of Alaska lack meteorological data; this is especially true for solid precipitation. Researchers at the University of Alaska Fairbanks, Water and Environmental Research Center have been collecting end-of-winter snow cover observations (depth, density, snow water equivalent and ablation) since the year 2000. These observations do not document the total snowfall during the winter, but provide quantitative estimate of cold season precipitation on the ground at winter’s end after sublimation and redistribution by wind. This report provides summary of snow cover data collected during cold season of 2012–2013. There are two main areas of study. One includes drainage areas of the western Sagavanirktok, Kuparuk, Itkillik, Anaktuvuk and Chandler Rivers located north of the continental divide in the Brooks Range. While the number of sites has varied each year, we visited 76 sites in April of 2013 on the North Slope of Alaska. Second study area was established in 2012 in the drainage areas of the Kogoluktuk, Mauneluk, Reed, Alatna, and Koyukuk Rivers south of the Brooks Range. Fifty seven new snow survey sites were visited south of the Brooks Range in April 2013. The cold season of 2012-2013 experienced heavy snowfalls (record amounts since 2000) north of the Brooks Range. This was the first year of data collection south of the Brooks Range, thus no comparison can be made. SWE averaged over entire study area was 13.1 cm in 2013, ranging from 1.2 cm to 35.2 cm. Generally, higher SWEs were found in the western portion of the study area. Ablation was later than normal in spring 2013. Ablation window extended from May 8, 2013 in the far south of the study area to middle June at higher elevations on the north side of the Brooks Range.
    • Snowmelt -frozen soil characteristics for a subarctic setting

      Kane, Douglas L.; Seifert, Richard D.; Fox, John D.; Taylor, George S. (University of Alaska, Institute of Water Resources, 1978-01)
      The pathways of soil water in cold climates are influenced, in addition to the normal forces, by the presence of permafrost and the temperature gradients in the soil system, whereas the infiltration of surface water into the soil system is a function of moisture levels, soil type and condition of the soil (whether it is frozen or not). Snowfall, with subsequent surface storage over a period of several months, typifies Alaskan winters. This snowfall often accounts for 50 per cent or more of the annual precipitation, with ablation occurring over a time span of 2 to 3 weeks in the spring. The melt period represents an event when large quantities of water may enter the soil system; the possibilities exist for recharging the groundwater system, or else generating surface runoff. The objective of this study was to determine the magnitude of potential groundwater recharge from snowmelt. Instrumentation was installed and monitored over two winter seasons to quantify the accumulation and ablation of the snowpack. Thermal and moisture data were collected to characterize the snow pack and soil conditions prior to, during, and following the ablation. Lysimeters were installed at various depths to intercept soil water. The volume of potential areal recharge for 1976 was 3.5 cm and for 1977 was 3.0 cm, which represented about 35 per cent of the maximum snowpack content. It is concluded that permafrost-free areas can contribute significantly to groundwater recharge during snowmelt ablation.
    • Snowmelt hydrology in the upper Kuparuk watershed, Alaska: observations and modeling

      Dean, Kelsey M.; Stuefer, Svetlana; Verbyla, David; Schnabel, William (2019-08)
      The Fourth National Climate Assessment Report (2018) indicates that Alaska has been warming at a rate two times greater than the global average with the Arctic continuing to be experiencing higher rates of warming. Snowmelt driven runoff is the largest hydrologic event of the year in many Alaska Arctic river systems. Changes to air temperature, permafrost, and snow cover impact the timing and magnitude of snowmelt runoff. This thesis examines the variability in hydrometeorological variables associated with snowmelt to better understand the timing and magnitude of snowmelt runoff in headwater streams of Arctic Alaska. The objectives of this thesis are to: (1) use observational data to evaluate trends in air temperature, precipitation, snow accumulation, and snowmelt runoff data; (2) relate precipitation, snow cover, and air temperature to snowmelt runoff using the physically-based Snowmelt Runoff Model (SRM) to test the applicability of the model for headwater streams in the Arctic. The focus of this study is the Upper Kuparuk watershed area, located in Alaska on the north side of the Brooks Range, where several monitoring programs have operated long enough to generate a 20-year climate record, 1993-2017. Long-term air temperature, precipitation, and streamflow data collected by the University of Alaska Fairbanks at the Water and Environmental Research Center and other agencies were used for statistical analysis and modeling. While no statistically significant trends in snow accumulation and snowmelt runoff were identified during 1993-2017, observations highlight large year-to-year variability and include extreme years. Snow water equivalent ranges from 5.4 to 17.6 cm (average 11.0 cm), peak snowmelt runoff ranges from 3.84 to 50.0 cms (average 22.4 cms), and snowmelt peak occurrence date ranges from May 13 to June 5 for the Upper Kuparuk period of record. The spring of 2015 stands out as the warmest, snowiest year on record in the Upper Kuparuk. To further investigate the runoff response to snowmelt in 2015, remote sensing snow data was analyzed and recommended parameters were developed for SRM use in the Upper Kuparuk watershed. Recommended parameters were then applied to 2013 snowmelt runoff as a test year. Model results varied between the two years and provide good first-order approximation of snowmelt runoff for headwater rivers in the Alaska Arctic.
    • Soil Stabilization Manual 2014 Update

      Hicks, R. Gary; Connor, Billy; McHattie, Robert (Alaska University Transportation Center, 2014-12)
      Soil Stabilization is used for a variety of activities including temporary wearing curses, working platforms, improving poor subgrade materials, upgrading marginal materials, dust control, and recycling old roads containing marginal materials. There are a number methods of stabilizing soils including modifying the gradation, the use of asphalt or cement stabilizers, geofiber stabilization and chemical stabilization. Selection of the method depends on the soil type, environment and application. This manual provide tools and guidance in the selection of the proper stabilization method and information on how to apply the method. A major portion of this manual is devoted to the use of stabilizing agents. The methods described here are considered best practices for Alaska.
    • Solar Assisted Culvert Thawing Device Phase I

      Zarling, John P. (1981-11)
      A solar assisted culvert thawing device has been designed, constructed, and installed as an alternate method for the prevention and control of roadway flooding and icing. The proposed solar thawing device is a maintenance-free system and relieves the labor-intensive and expensive culvert thawing methods presently used
    • Solar Assisted Culvert Thawing Device Phase II

      Zarling, John P.; Murray, Douglas H. (1983-05)
      A reflective type concentrating solar collector system has been designed, constructed and installed on an ice plugged roadway culvert as a means of melting a channel for water flow. The system consisted of four reflecting collectors, a circulating pump, and a thaw pipe mounted in the culvert. Photovoltaic panels were used as the source of power for the pump. A design analysis and performance characteristics are given for the solar collectors, circulating pump, and photovoltaic panels.
    • A Solar Design Manual for Alaska

      Seifert, Richard D. (1981-07)
    • Solar Energy Resource Potential in Alaska

      Seifert, Richard D.; Zarling, John P. (University of Alaska, Institute of Water Resources, 1978-03)
      Solar energy applications are receiving attention in Alaska as in much of the rest of the country. Solar energy possibilities for Alaska include domestic water heating, hot-water or hot-air collection for space heating, and the use of passive solar heating in residential or commercial buildings. As a first analysis, this study concentrated on applying solar energy to domestic hot-water heating needs (not space heating) in Alaska, and an analysis of solar hot-water heating economics was performed using the F-CHART solar energy simulation computer program. Results indicate that solar energy cannot compete economically with oil-heated domestic hot water at any of the five study locations in Alaska, but that it may be economical in comparison with electrically heated hot water if solar collector systems can be purchased and installed for $20 to $25 per square foot.
    • Solvent extraction procedure for the determination of tungsten in ores

      Rao, P.D. (University of Alaska Mineral Industry Research Laboratory, 1970-11)
      Atomic absorption methods have not been widely used for the determination of tungsten in ores due to its low sensitivity in aqueous solutions (1). A method has now been developed for solvent extraction of tungsten, making rapid determination of tungsten at low concentrations possible. It was found that tungstates, when converted to phosphotungstates, can be effectively extracted into di-isobutyl ketone (2-6 dimethyl - 4 - heptanone) (DIBK) containing Aliquat 336 (methyl tricapryl ammonium chloride from General Mills). This system was effectively used for the extraction of gold from cyanide solutioins (2). Even in aqueous solutions, phospho-tungstates give greater sensitivity (37 µg/ml for 1% absorption) compared to simple tungstates (63 µg/ml for 1% absorption). Standard tungsten solutions for extraction studies were prepared by converting aqueous solutions of sodium tungstate to sodium phospho-tungstate by boiling with ortho phosphoric acid. A Perkin-Elmer Model 303 atomic absorption spectrophotometer was used with a nitrous oxide-acetylene flame at a wavelength of 4008.75 A.
    • Some implications for Alaska of petroleum development on the Norwegian Continental Shelf

      Lynch, D.F. and Johansen, N.I. (University of Alaska Mineral Industry Research Laboratory, 1978-06)
      In January 1978, Senator Mike Gravel travelled in Norway to obtain information on Norwegian reactions to petroleum development on the continental shelf of the North and Norwegian Seas. This report presents some implications of Norwegian experiences which may be relevant to Alaska as developed by two University of Alaska professors who accompanied Senator Gravel and his assistant C. Deming Cowles.
    • Sounding rocket payload electrical systems designs system: a systems approach applied to the DIONISYS payload

      Burket, V. Edward (2002-08)
      Documentation of a comprehensive sounding rocket payload electrical system design methodology is needed by the Alaska Student Rocket Program (ASRP) in order to allow future student designers to build upon the knowledge and experience developed on previous sounding rocket missions, rather than rediscover valuable techniques that were never documented. A systems approach to sounding rocket payload design is presented and supported by a detailed presentation and analysis of the Hawkins/30.047UO 'DIONISYS' (D-region IONIzation measurement SYStem) payload design that was used to measure the D-Region ionization density at high latitudes. Fabrication techniques and test methods that ensure the payload will survive the launch environment are also presented, as well as a post-flight analysis of the successfully launched and recovered payload.
    • Southeastern Alaska mineral commodity maps

      Heiner, L.E. (University of Alaska Mineral Industry Research Laboratory, 1970)
      Continued interest by exploration companies in a Southeastern Alaska resource study in progress by the Mineral Industry Research Laboratory has prompted the release of some of the maps prior to the completion of the study. A report on the study should be available for distribution during the summer of 1970, and will contain a complete tabulation of all mineral properties and prospects contained in the literature or staked under the mining laws. In addition, the report will contain a description of U. S. Bureau of Mines mining districts, a summary of the geology, and thoughts pertaining to possible controls for ore deposits in the area. The commodity maps contained in this packet represent only those properties currently listed in the State Division of Mines and Geology Kardex System. Information pertaining to all properties tabulated in this system for Southeastern Alaska has been digitized and stored on magnetic tape. The maps were plotted by computer at a scale of approximately 1 " = 20 miles for overlay purposes. The computer utilized the storage and retrieval file of Alaska mineral information developed by the Mineral Industry Research Laboratory (see M. I. R. L. Report No. 24) and the STAMPEDE and contouring program maintained by the University of Alaska.computer center. Each map i s a composite of individually plotted quadrangle maps using the U. S. Geological Survey coordinate system described in U. S. Geological Survey Bulletin 1139 for property location. At this scale, there i s little error in location.
    • Specialized Testing of Asphalt Cements from Various ADOT&PF Paving Projects

      Hesp, Simon A. M. (Alaska University Transportation Center, 2015-06-10)
      The Alaska Department of Transportation and Public Facilities (ADOT&PF) sampled five different asphalt cements for specialized testing at Queen’s University in Kingston, Ontario. This report documents and discusses the findings. The tested asphalts were: PG 58-34, PG 52-40D, PG 52-40N, PG 58-28, and PG 64-28. Testing results showed that grade losses according to Ontario’s LS-308 Extended Bending Beam Rheometer (EBBR) ranged from 3.4°C to 6.3°C. Losses according to Ontario’s LS-228 Modified Pressure Aging Vessel (PAV) ranged from 0°C to 7.3°C. Grade losses of 3°C and higher are significant in terms of their ability to reduce pavement life cycles. Double-edge-notched tension (DENT) tests according to Ontario’s LS-299 DENT protocol were done on PAV residues. The critical crack tip opening displacement (CTOD) was determined and, at 15°C, it varied from a low of 19 mm for the PG 58-28 to a high of 175 mm for the PG 58-34. The PG 58- 40D showed a CTOD of 139 mm, contrasting with the low polymer PG 52-40N at only 36 mm, a nearly four-fold difference. All the results obtained from this specialized testing effort suggest that these materials will provide significant differences in performance. This report provides recommendations on how to obtain better value for money by implementing a few simple changes to the ADOT&PF asphalt cement specifications.
    • Spectral estimation of signal and noise power in rayleigh lidar measurements of the middle atmosphere

      Wang, Weiyuan (2003-08)
      A Rayleigh lidar has been operated at Chatanika, Alaska (65°N, 147°W) since November 1997. The lidar observations yield temperature and density measurements in the stratosphere and mesosphere (40-80 km). This thesis presents a systematic engineering analysis of the retrieval methods used to determine both the temperature and density profiles as well as the density perturbations. Statistical and spectral analysis techniques are used to determine the total power in the density perturbations and estimate the power component due to geophysical variability and the power component due to instrumental noise. The power in the density perturbations is used to characterize the gravity-wave activity at this high-latitude site. Seventy-four nights of observation yielded 60 observation periods of data of sufficient quality to estimate the rms amplitude of the relative density perturbation in the 40-50 km altitude region at 30 min resolution. For these observations the average rms amplitude has a value of 0.43%. Preliminary investigation of campaign measurements in the spring of 2003 indicates that higher values of rms wave amplitude are associated with the presence of mesospheric inversion layers.
    • Spectral estimation of wave-driven fluctuations in Rayleigh lidar temperature measurements

      Nadakuditi, Sharma (2005-05)
      The NICT-Rayleigh lidar has been operated at Chatanika, Alaska (65°N, l47°W) since November 1997. These lidar observations have yielded temperature and density measurements in the stratosphere and mesosphere (̃40-80 km). The goal of this thesis is to estimate the signal and noise power in the relative temperature perturbations. The uncertainties in these estimates due to instrumental variability and geophysical variability are also determined. This analysis quantifies the relative contributions of gravity waves and instrumental noise to the total power measured by the lidar. Eighty-nine nights of observations have yielded 80 sets of data that are of sufficient quality to study the gravity-wave activity at 30-minute resolution in the 40-50 km altitude region. The rms temperature and density perturbations from early August to mid-May are found to be statistically identical. The rms temperature fluctuations are found to have an average value of 0.44% with a maximum value of 1.28% on March 12th 2004 and a minimum value of 0.20% on September 16th 2003. These rms amplitudes are similar to values reported from other Arctic sites.
    • Speed -Sensorless Estimation And Position Control Of Induction Motors For Motion Control Applications

      Barut, Murat; Bogosyan, Seta; Hawkins, Joseph G.; Wies, Richard W.; Bracio, Boris (2006)
      High performance sensorless position control of induction motors (IMs) calls for estimation and control schemes which offer solutions to parameter uncertainties as well as to difficulties involved with accurate flux and velocity estimation at very low and zero speed. In this thesis, novel control and estimation methods have been developed to address these challenges. The proposed estimation algorithms are designed to minimize estimation error in both transient and steady-state over a wide velocity range, including very low and persistent zero speed operation. To this aim, initially single Extended Kalman Filter (EKF) algorithms are designed to estimate the flux, load torque, and velocity, as well as the rotor, Rr' or stator, Rs resistances. The temperature and frequency related variations of these parameters are well-known challenges in the estimation and control of IMs, and are subject to ongoing research. To further improve estimation and control performance in this thesis, a novel EKF approach is also developed which can achieve the simultaneous estimation of R r' and Rs for the first time in the sensorless IM control literature. The so-called Switching and Braided EKF algorithms are tested through experiments conducted under challenging parameter variations over a wide speed range, including under persistent operation at zero speed. Finally, in this thesis, a sensorless position control method is also designed using a new sliding mode controller (SMC) with reduced chattering. The results obtained with the proposed control and estimation schemes appear to be very compatible and many times superior to existing literature results for sensorless control of IMs in the very low and zero speed range. The developed estimation and control schemes could also be used with a variety of the sensorless speed and position control applications, which are challenged by a high number of parameter uncertainties.