• Oat production in Alaska

      Higgins, F. L. (Office of Experiment Stations, United States Department of Agriculture, 1932-06)
      The oat crop occupies an important place on the farms in interior Alaska, especially in the Matanuska Valley and the Fairbanks region of the Tanana Valley. The crop is used chiefly for hay. It is one of the more important grain crops in the system of diversified farming recommended for Alaska by the Alaska Agricultural Experiment Stations. Good yields for hay and silage can be produced in southeastern Alaska, but production is limited (1) by the small areas of suitable land available for farming, (2) by the high cost of clearing the land, and (3) by cool, wet weather in the fall which makes difficult the work of harvesting. Southeastern Alaska is rough, rugged, and heavily timbered and has comparatively little land available for cultivation. Oats can not be depended upon to mature at Kenai, on Cook Inlet, because of the unfavorable weather prevailing there. However, oats can be grown in that region for hay and silage. The cool, rainy weather in the fall is more favorable for silage making than for haymaking. A small area of oats is grown for forage in the Homer region on Cook Inlet. This region is well suited to oats and vetch, and also to oats and peas for hay and silage. Weather conditions there, as in the Kenai region, are adverse to the ripening of oats. Oat growing in the Tanana Valley, near Fairbanks, began about 1907 with the production of hay for horses, shortly after the establishment of a mining camp in the valley. A number of horses were used in the region for freighting, and as timothy hay had to be shipped in from the States at a cost of more than $100 per ton, some of the teamsters decided to clear their lands and grow oat hay for the local market. Oat hay of good quality brought from $60 to $90 per ton, depending upon market requirements. Oats for forage is an important crop in this region. The native bluetop grass (Calamagrostiis spp.) is found growing only in certain localities, and then in irregular patches. Experience has shown that it does not withstand cutting in successive years. Hardy, high-yielding biennial or perennial legumes have not yet been found which will produce as high tonnage per acre as do oats, in interior Alaska. Oats seeded with peas or with vetch for hay have been found to make an efficient silage material. The addition of legumes to the ration improves the feeding value of the hay and is especially desirable for dairy cows and young stock. Because of inadequate threshing facilities, oats were not grown for grain for some time. However, with the introduction and development of early-maturing varieties of oats and the purchase of a threshing machine by the station for station and community use, farmers began seeding oats for grain. Alaska farmers follow different methods in growing oats. Some plow in the fall, others in the spring, and still others not at all. Those who do not plow prepare the seed bed by disking and harrowing in the spring. Again, some farmers follow a definite scheme of rotation to conserve and increase soil fertility and to lessen loss from crop diseases, whereas others broadcast their grain seed without being reasonably sure that it is free from disease. As a result of general poor management much of the land under cultivation is low in fertility and badly infested with weeds, making it necessary to give attention to weed control. This bulletin, based on observations and experiments in different parts of Alaska, has been prepared for the purpose of assisting farmers of the Territory to grow oats successfully.
    • Oats and Barley growing and storing grain in Alaska's Matanuska and Tanana valleys, 1957-1958

      Branton, C. Ivan (Alaska Agricultural Experiment Station, 1959-12)
      Plant before June 1 for best yields and quality, and to improve chances for a September harvest. Control weeds to improve acre yields, to utilize fertilizer efficiently, and to reduce storage problems caused by wet weed seed. Do not rely on field drying grain to a safe storage moisture content. Have some means of artificial drying ready at harvest time. Plan on September harvest to utilize the best chance of favorable field drying conditions, and to reduce shattering losses.
    • Obfuscation fingerprinting in Android binaries

      Van Veldhuizen, Matthew Philip (2015-04)
      There are many way to protect code from reverse engineering. One such way is to obfuscate either the source code, machine code or bytecode. Obfuscating Android applications not only makes it harder to reverse engineer, it can also speed up execution by reducing the size of the application and removing unnecessary code. One method of obfuscation is to do it manually and the other method is to use an obfuscation program. However, it may become necessary to reverse obfuscation, because of the loss of source code or when investigating malware, trojans, or other harmful applications. This process is called deobfuscation. Once an application has been obfuscated performing deobfuscation is a tedious task, and knowing how the application was obfuscated would increase the probability of correctly reversing the obfuscation. By examining four Android application obfuscators I successfully identified distinct fingerprints within each of the obfuscated binaries by building a simple Android application, obfuscating it, and then comparing obfuscated and unobfuscated bytecode. Using these fingerprints I was able to associate each obfuscator with an approximate probability that it was used to perform the obfuscation.
    • Oblique impact cratering: A comparison of low-velocity experiments to high-velocity experiments

      Hessen, Katie K.; Hessen, Robert; Dean, Ken; West, Michael; Chappelow, John; Christensen, Douglas (2008-12)
      Previous impact cratering experiments performed by Gault and Wedekind (1978), used high-velocity impactors (~1 km/s to 7 km/s) to quantify how impact angle affects crater morphology and ejecta pattern. Low velocity (144 m/s to 260 m/s) impact experiments were conducted in a vacuum chamber with a basaltic sand target material and impact angles ranging from 0.5° to 90° (vertical) at the Impact Cratering Laboratory at the University of Tokyo Kashiwa. The crater morphology and ejecta distribution from low velocity impacts are then compared to results from the higher velocity projectiles. When adjustments are made to the low-velocity measurements to account for differences in velocity, the displaced mass ratio follows a sinθ distribution, as is seen in the high- velocity experiments. In the low-velocity experiments, asymmetric ejecta is present at slightly higher impact angles. The presence of an uprange forbidden zone occurs at the same impact angle (20°) in both sets of experiments. The most striking difference between the two sets of experiments is the complete lack of a downrange forbidden zone in all of the low-velocity experiments. With the exception of the very lowest impact angles, these low-velocity oblique impact experiments yield similar changes in crater characteristics with varying impact angles to the previous high-velocity experiments.
    • Observable effects of attention, posture, ergonomics and movement in the classroom

      Healy, Joanne; Bult-Ito, Abel; Anahita, Sine; Charles, Walkie; Irish, Joel; Kaden, Ute (2014-05)
      Two studies related to student attention, posture, school ergonomics, student behavior (leaning, standing up, and moving), and learning engagement were conducted in Alaska. The Children's Postural Improvement Study (CPIS) looked at the observable effects of two interventions on attention. In the Classroom Environmental Study (CES) a baseline ergonomic survey compared observed student behavior and classroom arrangements. The purpose of the CPIS was to investigate the effects of a postural education program, consisting of five 30-minute instructional sessions, as compared to a nutritional intervention at two elementary schools and its effect on attention. Three quantitative tools measured attention, the post-Partial Vanderbilt ADHD Teacher and Parent rating scales and pre- and post-math fluency tests. Qualitative measures included pre- and postintervention photographs, daily comments from students after the lesson, and post open-ended-question student and teacher surveys. Based on the post-surveys, participants valued their good posture and made concentrated efforts to improve it. Quantitative results of this postural study revealed no correlation between posture and attention. The follow-up CES examined the current state of furniture in 78 classrooms and pedagogical practices in regard to student movement and learning engagement in eight fourth-grade classrooms in three elementary schools. Two-way ANOVA revealed a significant school effect for leaning and significant classroom nested within school effects for leaning, standing up, and moving. Classroom sketches were coded to examine movement and posture. No significant difference for desk clusters by grade, or by school using the Chi-squared test were found, but there was a significant difference comparing the seating relationship to instructional delivery by grade and by school. Recommendations for future research and changes within Schools of Education and school districts to improve posture and learning engagement include: adjust current students' chairs and desks to meet their ergonomic needs; raise awareness of and inform pre-service, current teachers, students, and parents about ergonomic health concepts; encourage teachers to move around the classroom while instructing to engage students as they track the teacher's movement; and limit instructional periods to 20 minutes or less to allow for student movement breaks.
    • Observation and analysis of whistler mode echoes received by RPI on IMAGE at high latitudes

      Chen, Xiangdong (2001-05)
      Whistler-mode wave-injection experiments with Radio Plasma Imager (RPI) on IMAGE offer an opportunity to observe the whistler-mode echoes. We have performed raytracing studies to investigate accessibility of whistler-mode waves injected from IMAGE to various regions of the magnetosphere and also to other satellites such as Akebono. RPI detected both discrete and diffuse whistler-mode echoes during our observing period (April 21 to August 28, 2000) when IMAGE was at a low altitude (1̃000-7000 km) and mid-to-high latitudes (>25 - 40S̊) near its perigee. We believe that the discrete echoes are the result of RPI signals reflected at the Earth-ionosphere boundary and the diffuse echoes are the result of scattering of RPI signals by meter-scale irregularities. Raytracing analysis shows that both ducted and nonducted ray propagation are needed to explain the observed whistler-mode dispersion. Comparison of electron densities obtained from our raytracing analysis of dispersion with the electron densities obtained by Kletzing et al. in the Auroral Zone shows that these density values deduced from RPI data were about ten times higher. This may be because the antenna radiation efficiency is higher at higher electron densities.
    • Observation and analysis on the characteristics of strain induced by frost heave for a full-scale buried, chilled gas pipeline

      Yang, Kun; Huang, Scott; Chen, Gang; Darrow, Margaret (2013-12)
      This thesis examines the strain characteristics of a large-scale, buried chilled gas pipeline in the discontinuous permafrost region. A full-scale chilled pipeline gas experiment was conducted in Fairbanks, Alaska. The test pipeline had a length of 105 m and a diameter of 0.9 m. One-third of the pipeline was located in permafrost and the rest was in non-permafrost. The monitoring data were collected from December 1999 to January 2005 including both freezing and thawing phases. In the transition zone between frozen and unfrozen soil, the foundation experienced a vertical movement caused by differential frost heave. The test results indicated that the bending action was the main factor for the pipeline for the circumferential and longitudinal strain distribution of the pipeline. Moreover, linear relationships were developed between frost heave and the longitudinal strain at the top and the bottom (i.e., 0� and 180�) of the pipe. The developed equations can be used to predict the strain of the pipe caused by differential frost heave for future tests with similar site conditions.
    • Observations and generation mechanisms of slow-mode waves in the magnetosheath

      Yan, Ming; Lee, Lou; Craven, John; Hawkins, Joseph; Sentman, Dave; Watkins, Brenton (1995)
      The interaction of solar wind with the geomagnetic field leads to the formation of the bow shock, magnetosheath, and magnetopause. Magnetohydrodynamic (MHD) slow-mode structures with a plasma density enhancement and magnetic field depression have been observed to appear frequently in the inner magnetosheath. In addition, the slow-mode structures usually consist of slow-mode waves with a smaller length scale. These slow-mode structures and waves are studied in this thesis through satellite observations and numerical simulations. We find, through satellite observations, that some of the slow-mode structures are associated with Alfven waves in the solar wind. On the other hand, simulations show that slow-mode waves are generated through the interactions between the bow shock and interplanetary shocks, magnetosonic waves, rotational discontinuities, or Alfven waves. The generated slow-mode waves stay in the inner magnetosheath for a long time (about 15 minutes) before the wave energy is convected away tailward. Of particular importance are the interactions between the bow shock and interplanetary rotational discontinuities or Alfven waves. These interactions generate a region with an enhanced plasma density and depressed magnetic field, which is very similar to the slow-mode structures observed in the inner magnetosheath. Based on observations and simulations, it is suggested that the interactions of various types of solar wind fluctuations with the bow shock may lead to the frequent appearance of slow-mode structures and waves in the inner magnetosheath. The generated slow-mode structures have strong pressure variations, and may impinge on the magnetopause as strong pressure pulses.
    • Observations Of Metal Concentrations In E-Region Sporadic Thin Layers Using Incoherent-Scatter Radar

      Suzuki, Nobuhiro; Watkins, Brenton (2006)
      This thesis has used incoherent-scatter radar data from the facility at Sondrestrom, Greenland to determine the ion mass values inside thin sporadic-E layers in the lower ionosphere. Metallic positively-charged ions of meteoric origin are deposited in the earth's upper atmosphere over a height range of about 85-120 km. Electric fields and neutral-gas (eg N2, O, O2) winds at high latitudes may produce convergent ion dynamics that results in the re-distribution of the background altitude distribution of the ions to form thin (1-3 km) high-density layers that are detectable with radar. A large database of experimental radar observations has been processed to determine ion mass values inside these thin ion layers. The range resolution of the radar was 600 meters that permitted mass determinations at several altitude steps within the layers. Near the lower edge of the layers the ion mass values were in the range 20-25 amu while at the top portion of the layers the mass values were generally in the range 30-40 amu. The numerical values are consistent with in-situ mass spectrometer data obtained by other researchers that suggest these layers are mainly composed of a mixture or Mg +, Si+, and Fe + ions. The small tendency for heavier ions to reside at the top portion of the layers is consistent with theory. The results have also found new evidence for the existence of complex-shaped multiple layers; the examples studied suggest similar ion mass values in different layers that in some cases are separated in altitude by several km.
    • Observations on Plant and Tuber Growth of Potato in Alaska

      Dearborn, Curtis H. (School of Agriculture and Land Resources Management, Agricultural and Forestry Experiment Station, 1981-04)
      Several phenotypic characteristics that otherwise would be diffult to observe under field conditions in temperate-zone latitudes are amplified in Alaska at 61° 34' and north. At this latitude, the growing season for potato is marked by cool temperatures at its beginning and end as well as long daylight periods. Characteristics that have been observed include: rosetting, skirts-up, leaf color change, wet leaf, perforated leaf, fasciation, inverted leaf, flowering, stolon plant production, double tuber, second growth, stolon extension, tuber constriction, eye depth, heat sprout, cracking, tuberization, frost resistance, fruit set, sprout tuber, and sprout necrosis. Stolon plant production and tuberization have been noted for samples of 27 Solanum species. Numerous plant- and tuber-growth manifestations are shown. Seed tubers of potato varieties stored over winter under identical conditions manifest significant differences in their capacity to generate a top following field planting. Stolon growth, stolon plant development, and tuberization indicate that a delicate physiological balance exists in some clones relative to the Alaskan environment. Changes in tuber shape, eye depth, and second growth are manifestations of environmental changes of rather short duration. Possibly heat sprout results from damage to the potato by particular foreign bodies. Iopride showed the least rosetting and this character is conspicuous in some of its progeny. Leaves of some clones dosed in toward the stem during light conditions approximating twilight. A few clones exhibited inverted leaf as a growth response to low light intensity while two clones lost their green color at the apex. Perforated leaf of potato and fireweed in the Matanuska Valley has been traced to aphid-feeding injury. Plants grown from tubers of potatoes with perforated leaves did not exhibit the perforated-leaf condition.
    • Observations on the Alaska reindeer situation, 1968.

      Hickok, David M. (Alaska Cooperative Wildlife Research Unit, 1968-01-24)
    • Observed Scarification Rates And Contract Costs For the TTS-35 Disc Trencher in Interior Alaska

      Richmond, Allen P.; Malone, Thomas (Agriculture and Forestry Experiment Station, School of Agriculture and Land Resources Management, University of Alaska-Fairbanks, 1986-03)
      The regeneration of interior Alaska’s commercial forest lands is mandated by Alaska’s Forest Resources and Practices Act (1979). This act requires that regeneration be established adequate to ensure a sustained yield on forested lands from which the timber has been harvested. Post-logging regeneration efforts now are aimed at exposing mineral soil for the natural seeding of white spruce. Soil exposure has been accomplished by blade scarifying with a crawler tractor which provides large seed sites or by using a Bracke-type patch scarifier which produces small seed sites of about 2 ft2. Arlidge (1967) reports that larger seedbeds have greater regeneration success than smaller ones. Some researchers have found that the regeneration of the larger plots may be too successful, requiring weeding and precommercial thinning to bring stocking to satisfactory levels (Zasada and Grigal 1978). The Alaska Division of Forestry (DOF) has not been satisfied with the cost or effectiveness of either of these site-preparation practices.
    • Obstacle detection with Kinect V2 on a ground robot

      Fisher, Laurin; Lawlor, Orion; Hartman, Chris; Genetti, Jon (2018-12)
      This paper is about determining whether using a Kinect V2 (Xbox One Kinect) mounted on a LAYLA ground robot can be used to detect obstacles, by generating a heightmap with the depth data. We take several factors into consideration including: framerate, power consumption, field of view, and data noise.
    • The occurrence and characteristics of plastic pollution in Alaska's marine birds

      Day, Robert H. (1980-05)
      Major aspects of the occurrence and variation of plastic particles in the stomachs of marine birds in Alaska were examined. A total of 448 of 1 ,968 individuals and 15 of 37 species of marine birds contained plastic. Species feeding primarily by pursuit-diving and surface-seizing had the highest incidence of plastic. Crustaceanand cephalopod-feeders had a higher incidence of plastic than did fish-feeders. Birds from the Aleutian Islands averaged more particles than did birds elsewhere in Alaska. No sexual differences in plastic ingestion were found, but subadults averaged more plastic than did adults. There was a general increase in plastic ingestion between 1969 and 1977. An annual cycle of plastic ingestion was recorded, with the greatest ingestion in mid-summer. No overt effects of plastic on the physical well-being of the birds were found, but non-breeding in the Parakeet Auklet may have been caused by high plastic ingestion.
    • Occurrence and distribution of barite in the permo-triassic siksikpuk formation along the Brooks Range haul road

      Payne, M.W. (University of Alaska Mineral Industry Research Laboratory, 1980-03)
      Barite commonly occurs in Permian to Triassic age rocks along the north flank of the Brooks Range. The Siksikpuk Formation (Wolfcampian to lowest Guadalupian age) is noted for its barite and is well exposed in the vicinity of Galbraith Lake along the pipeline haul road (Figure 1). The proximity of these barite deposits to an existing road made them a logical selection for investigation. The study was designed to provide detailed stratigraphic information on barite quantity and quality, associated clay mineralogy, and relationship of barite to environments of deposition.
    • Occurrence patterns of whistler mode (WM) echoes observed by RPI/IMAGE and their relation to geomagnetic activity

      Reddy, Amani (2007-12)
      This thesis presents an analysis of whistler mode (WM) echoes observed at altitudes less than 5,000 km by the Radio Plasma Imager (RPI) on the IMAGE satellite. WM echoes are generated either by specular reflection (SR) of RPI signals at the Earth-ionosphere boundary (~90 km) or by magnetospheric reflection of RPI signals [...] at altitudes greater than 1,000 km [Sonwalkar et al., 2004; Sonwalkar et al., 2006]. These echoes are further influenced by field aligned irregularities (FAI) and are categorized into discrete, multipath or diffuse SR- and MR- WM echoes, based on their characteristic spectral forms. A survey of WM echoes observed during January 2004- December 2005 showed that WM echoes occurred at all latitudes and under moderate geomagnetic conditions. Occurrence patterns of WM echoes observed in August-December 2005 during geomagnetically quiet and disturbed periods indicate that geomagnetic storms lead to significant changes in FAI that affect the propagation of WM echoes. Our results help (1) in better understanding propagation and generation mechanisms of naturally occurring WM waves, and (2) in planning future WM wave injection experiments in space.
    • Ocean heat effect on the observed and predicted reduction of the Arctic sea ice: results of the AARI contribution to ACCESS WP1

      Ivanov, Vladimir; Ashik, Igor (2013-03)
      Under conditions of reducing ice cover the influence of ocean heat on Arctic sea ice is expected to increase. We are identifying several ways how the ocean heat may be transferred towards the ice contributing to the existent ice thinning and/or impeding new ice formation. They include: Direct impact of sensible heat, stored in the ocean on the ice cover in the locations close to the warm inflow of Atlantic Water (AW) and Pacific Water (PW); Vertical heat flux via double diffusion convection from AW layer in the central Arctic Basin Increased upward heat flux from AW over continental slope and outer shelf, where AW upwells the shelf, and vertical mixing is enhanced due to strong shear, tidal currents, and shelf intrusions; Atmospheric heat accumulation in the melted water, which enhances lateral ice erosion.
    • Ocean Wilderness In Theory And Practice

      Barr, Bradley W.; Kruse, Gordon; Kliskey, Andrew; Alessa, Lilian; Koester, David (2012)
      Wilderness preservation has been an important focus of resource conservation since the dwindling number of wild places was perceived by some as losing a valued part of our collective natural and cultural heritage. While wilderness preservation efforts have been almost entirely focused on the land, recently there has been growing interest in "ocean wilderness." However, implementation has been constrained by the lack of a common vision of how "wilderness" is applied to the ocean, and how such areas should be managed and preserved. The purpose of this work was to identify and evaluate potential definitions of ocean wilderness and the values and qualities such areas possess, and to determine how they might be effectively identified and managed to preserve their wilderness character. This research focused on articulating a robust definition for "wilderness waters," within the context of how wilderness is currently conceived and articulated in law and policy, as well as evaluating how such areas might be most appropriately identified and managed. Extensive inventories were conducted of existing ocean wilderness areas, focused on North America, to determine what currently exists, how these areas are managed, and how future ocean wilderness designations should be prioritized. A survey was conducted, targeting resource managers and scientists, to identify preferences and perceptions of ocean wilderness and its potential stewardship. The survey results suggested that coastal waters possessed considerable values and qualities of wilderness, particularly areas adjacent to existing designated wilderness, that certain human uses might be appropriately permitted, and that there was much support for expanding the area of coastal waters designated as wilderness. The research also suggested that the North American Arctic might offer many opportunities for preserving ocean wilderness, in close collaboration with the Indigenous communities in this region. A number of recommendations were offered including that priority should be given to evaluating and designating areas adjacent to designated coastal wilderness areas, that the existing legal and policy framework in North America can be effectively used to expand the "wilderness waters" system, and that more work needs to be done to build the constituencies of support essential to accomplish this task.