Lunar map showing traverse plans for Apollo 14 lunar landing mission
1970-09-01
This lunar map shows the traverse plans for the Apollo 14 lunar landing mission. Areas marked include Lunar module landing site, areas for the Apollo Lunar Surface Experiment Package (ALSEP) and areas for gathering of core samples.
Scheirer, Daniel S.; Andreasen, Arne Dossing
2008-01-01
In March 2008, we collected gravity data along 12 traverses across newly-mapped faults in the Moapa Valley region of Clark County, Nevada. In areas crossed by these faults, the traverses provide better definition of the gravity field and, thus, the density structure, than prior gravity observations. Access problems prohibited complete gravity coverage along all of the planned gravity traverses, and we added and adjusted the locations of traverses to maximize our data collection. Most of the traverses exhibit isostatic gravity anomalies that have gradients characteristic of exposed or buried faults, including several of the newly-mapped faults.
Expanding the Detection of Traversable Area with RealSense for the Visually Impaired
Yang, Kailun; Wang, Kaiwei; Hu, Weijian; Bai, Jian
2016-01-01
The introduction of RGB-Depth (RGB-D) sensors into the visually impaired people (VIP)-assisting area has stirred great interest of many researchers. However, the detection range of RGB-D sensors is limited by narrow depth field angle and sparse depth map in the distance, which hampers broader and longer traversability awareness. This paper proposes an effective approach to expand the detection of traversable area based on a RGB-D sensor, the Intel RealSense R200, which is compatible with both indoor and outdoor environments. The depth image of RealSense is enhanced with IR image large-scale matching and RGB image-guided filtering. Traversable area is obtained with RANdom SAmple Consensus (RANSAC) segmentation and surface normal vector estimation, preliminarily. A seeded growing region algorithm, combining the depth image and RGB image, enlarges the preliminary traversable area greatly. This is critical not only for avoiding close obstacles, but also for allowing superior path planning on navigation. The proposed approach has been tested on a score of indoor and outdoor scenarios. Moreover, the approach has been integrated into an assistance system, which consists of a wearable prototype and an audio interface. Furthermore, the presented approach has been proved to be useful and reliable by a field test with eight visually impaired volunteers. PMID:27879634
Integrating Terrain Maps Into a Reactive Navigation Strategy
NASA Technical Reports Server (NTRS)
Howard, Ayanna; Werger, Barry; Seraji, Homayoun
2006-01-01
An improved method of processing information for autonomous navigation of a robotic vehicle across rough terrain involves the integration of terrain maps into a reactive navigation strategy. Somewhat more precisely, the method involves the incorporation, into navigation logic, of data equivalent to regional traversability maps. The terrain characteristic is mapped using a fuzzy-logic representation of the difficulty of traversing the terrain. The method is robust in that it integrates a global path-planning strategy with sensor-based regional and local navigation strategies to ensure a high probability of success in reaching a destination and avoiding obstacles along the way. The sensor-based strategies use cameras aboard the vehicle to observe the regional terrain, defined as the area of the terrain that covers the immediate vicinity near the vehicle to a specified distance a few meters away.
Spirit rover localization and topographic mapping at the landing site of Gusev crater, Mars
Li, R.; Archinal, B.A.; Arvidson, R. E.; Bell, J.; Christensen, P.; Crumpler, L.; Des Marais, D.J.; Di, K.; Duxbury, T.; Golombek, M.P.; Grant, J. A.; Greeley, R.; Guinn, J.; Johnson, Aaron H.; Kirk, R.L.; Maimone, M.; Matthies, L.H.; Malin, M.; Parker, T.; Sims, M.; Thompson, S.; Squyres, S. W.; Soderblom, L.A.
2006-01-01
By sol 440, the Spirit rover has traversed a distance of 3.76 km (actual distance traveled instead of odometry). Localization of the lander and the rover along the traverse has been successfully performed at the Gusev crater landing site. We localized the lander in the Gusev crater using two-way Doppler radio positioning and cartographic triangulations through landmarks visible in both orbital and ground images. Additional high-resolution orbital images were used to verify the determined lander position. Visual odometry and bundle adjustment technologies were applied to compensate for wheel slippage, azimuthal angle drift, and other navigation errors (which were as large as 10.5% in the Husband Hill area). We generated topographic products, including 72 ortho maps and three-dimensional (3-D) digital terrain models, 11 horizontal and vertical traverse profiles, and one 3-D crater model (up to sol 440). Also discussed in this paper are uses of the data for science operations planning, geological traverse surveys, surveys of wind-related features, and other science applications. Copyright 2006 by the American Geophysical Union.
Stereo-vision-based terrain mapping for off-road autonomous navigation
NASA Astrophysics Data System (ADS)
Rankin, Arturo L.; Huertas, Andres; Matthies, Larry H.
2009-05-01
Successful off-road autonomous navigation by an unmanned ground vehicle (UGV) requires reliable perception and representation of natural terrain. While perception algorithms are used to detect driving hazards, terrain mapping algorithms are used to represent the detected hazards in a world model a UGV can use to plan safe paths. There are two primary ways to detect driving hazards with perception sensors mounted to a UGV: binary obstacle detection and traversability cost analysis. Binary obstacle detectors label terrain as either traversable or non-traversable, whereas, traversability cost analysis assigns a cost to driving over a discrete patch of terrain. In uncluttered environments where the non-obstacle terrain is equally traversable, binary obstacle detection is sufficient. However, in cluttered environments, some form of traversability cost analysis is necessary. The Jet Propulsion Laboratory (JPL) has explored both approaches using stereo vision systems. A set of binary detectors has been implemented that detect positive obstacles, negative obstacles, tree trunks, tree lines, excessive slope, low overhangs, and water bodies. A compact terrain map is built from each frame of stereo images. The mapping algorithm labels cells that contain obstacles as nogo regions, and encodes terrain elevation, terrain classification, terrain roughness, traversability cost, and a confidence value. The single frame maps are merged into a world map where temporal filtering is applied. In previous papers, we have described our perception algorithms that perform binary obstacle detection. In this paper, we summarize the terrain mapping capabilities that JPL has implemented during several UGV programs over the last decade and discuss some challenges to building terrain maps with stereo range data.
Stereo Vision Based Terrain Mapping for Off-Road Autonomous Navigation
NASA Technical Reports Server (NTRS)
Rankin, Arturo L.; Huertas, Andres; Matthies, Larry H.
2009-01-01
Successful off-road autonomous navigation by an unmanned ground vehicle (UGV) requires reliable perception and representation of natural terrain. While perception algorithms are used to detect driving hazards, terrain mapping algorithms are used to represent the detected hazards in a world model a UGV can use to plan safe paths. There are two primary ways to detect driving hazards with perception sensors mounted to a UGV: binary obstacle detection and traversability cost analysis. Binary obstacle detectors label terrain as either traversable or non-traversable, whereas, traversability cost analysis assigns a cost to driving over a discrete patch of terrain. In uncluttered environments where the non-obstacle terrain is equally traversable, binary obstacle detection is sufficient. However, in cluttered environments, some form of traversability cost analysis is necessary. The Jet Propulsion Laboratory (JPL) has explored both approaches using stereo vision systems. A set of binary detectors has been implemented that detect positive obstacles, negative obstacles, tree trunks, tree lines, excessive slope, low overhangs, and water bodies. A compact terrain map is built from each frame of stereo images. The mapping algorithm labels cells that contain obstacles as no-go regions, and encodes terrain elevation, terrain classification, terrain roughness, traversability cost, and a confidence value. The single frame maps are merged into a world map where temporal filtering is applied. In previous papers, we have described our perception algorithms that perform binary obstacle detection. In this paper, we summarize the terrain mapping capabilities that JPL has implemented during several UGV programs over the last decade and discuss some challenges to building terrain maps with stereo range data.
The role of photogeologic mapping in traverse planning: Lessons from DRATS 2010 activities
Skinner, James A.; Fortezzo, Corey M.
2013-01-01
We produced a 1:24,000 scale photogeologic map of the Desert Research and Technology Studies (DRATS) 2010 simulated lunar mission traverse area and surrounding environments located within the northeastern part of the San Francisco Volcanic Field (SFVF), north-central Arizona. To mimic an exploratory mission, we approached the region “blindly” by rejecting prior knowledge or preconceived notions of the regional geologic setting and focused instead only on image and topographic base maps that were intended to be equivalent to pre-cursor mission “orbital returns”. We used photogeologic mapping techniques equivalent to those employed during the construction of modern planetary geologic maps. Based on image and topographic base maps, we identified 4 surficial units (talus, channel, dissected, and plains units), 5 volcanic units (older cone, younger cone, older flow, younger flow, and block field units), and 5 basement units (grey-toned mottled, red-toned platy, red-toned layered, light-toned slabby, and light-toned layered units). Comparison of our remote-based map units with published field-based map units indicates that the two techniques yield pervasively similar results of contrasting detail, with higher accuracies linked to remote-based units that have high topographic relief and tonal contrast relative to adjacent units. We list key scientific questions that remained after photogeologic mapping and prior to DRATS activities and identify 13 specific observations that the crew and science team would need to make in order to address those questions and refine the interpreted geologic context. We translated potential observations into 62 recommended sites for visitation and observation during the mission traverse. The production and use of a mission-specific photogeologic map for DRATS 2010 activities resulted in strategic and tactical recommendations regarding observational context and hypothesis tracking over the course of an exploratory mission.
Single-Frame Terrain Mapping Software for Robotic Vehicles
NASA Technical Reports Server (NTRS)
Rankin, Arturo L.
2011-01-01
This software is a component in an unmanned ground vehicle (UGV) perception system that builds compact, single-frame terrain maps for distribution to other systems, such as a world model or an operator control unit, over a local area network (LAN). Each cell in the map encodes an elevation value, terrain classification, object classification, terrain traversability, terrain roughness, and a confidence value into four bytes of memory. The input to this software component is a range image (from a lidar or stereo vision system), and optionally a terrain classification image and an object classification image, both registered to the range image. The single-frame terrain map generates estimates of the support surface elevation, ground cover elevation, and minimum canopy elevation; generates terrain traversability cost; detects low overhangs and high-density obstacles; and can perform geometry-based terrain classification (ground, ground cover, unknown). A new origin is automatically selected for each single-frame terrain map in global coordinates such that it coincides with the corner of a world map cell. That way, single-frame terrain maps correctly line up with the world map, facilitating the merging of map data into the world map. Instead of using 32 bits to store the floating-point elevation for a map cell, the vehicle elevation is assigned to the map origin elevation and reports the change in elevation (from the origin elevation) in terms of the number of discrete steps. The single-frame terrain map elevation resolution is 2 cm. At that resolution, terrain elevation from 20.5 to 20.5 m (with respect to the vehicle's elevation) is encoded into 11 bits. For each four-byte map cell, bits are assigned to encode elevation, terrain roughness, terrain classification, object classification, terrain traversability cost, and a confidence value. The vehicle s current position and orientation, the map origin, and the map cell resolution are all included in a header for each map. The map is compressed into a vector prior to delivery to another system.
NASA Technical Reports Server (NTRS)
Feng, Wanda; Evans, Cynthia; Gruener, John; Eppler, Dean
2014-01-01
Geologic mapping involves interpreting relationships between identifiable units and landforms to understand the formative history of a region. Traditional field techniques are used to accomplish this on Earth. Mapping proves more challenging for other planets, which are studied primarily by orbital remote sensing and, less frequently, by robotic and human surface exploration. Systematic comparative assessments of geologic maps created by traditional mapping versus photogeology together with data from planned traverses are limited. The objective of this project is to produce a geologic map from data collected on the Desert Research and Technology Studies (RATS) 2010 analog mission using Apollo-style traverses in conjunction with remote sensing data. This map is compared with a geologic map produced using standard field techniques.
USDA-ARS?s Scientific Manuscript database
Genome maps can be thought of much like road maps except that, instead of traversing across land, they traverse across the chromosomes of an organism. Genetic markers serve as landmarks along the chromosome and provide researchers information as to how close they may be to a gene or region of inter...
Quantifying Traversability of Terrain for a Mobile Robot
NASA Technical Reports Server (NTRS)
Howard, Ayanna; Seraji, Homayoun; Werger, Barry
2005-01-01
A document presents an updated discussion on a method of autonomous navigation for a robotic vehicle navigating across rough terrain. The method involves, among other things, the use of a measure of traversability, denoted the fuzzy traversability index, which embodies the information about the slope and roughness of terrain obtained from analysis of images acquired by cameras mounted on the robot. The improvements presented in the report focus on the use of the fuzzy traversability index to generate a traversability map and a grid map for planning the safest path for the robot. Once grid traversability values have been computed, they are utilized for rejecting unsafe path segments and for computing a traversalcost function for ranking candidate paths, selected by a search algorithm, from a specified initial position to a specified final position. The output of the algorithm is a set of waypoints designating a path having a minimal-traversal cost.
NASA Astrophysics Data System (ADS)
Losiak, Anna; Orgel, Csilla; Moser, Linda; MacArthur, Jane; Gołębiowska, Izabela; Wittek, Steffen; Boyd, Andrea; Achorner, Isabella; Rampey, Mike; Bartenstein, Thomas; Jones, Natalie; Luger, Ulrich; Sans, Alejandra; Hettrich, Sebastian
2013-04-01
The MARS2013 mission: The Austrian Space Forum together with multiple scientific partners will conduct a Mars analog field simulation. The project takes place between 1st and 28th of February 2013 in the northern Sahara near Erfoud. During the simulation a field crew (consisting of suited analog astronauts and a support team) will conduct several experiments while being managed by the Mission Support Center (MSC) located in Innsbruck, Austria. The aim of the project is to advance preparation of the future human Mars missions by testing: 1) the mission design with regard to operational and engineering challenges (e.g., how to work efficiently with introduced time delay in communication between field team and MSC), 2) scientific instruments (e.g., rovers) and 3) human performance in conditions analogous to those that will be encountered on Mars. The Role of Geological Mapping: Remote Science Support team (RSS) is responsible for processing science data obtained in the field. The RSS is also in charge of preparing a set of maps to enable planning activities of the mission (including the development of traverses) [1, 2]. The usage of those maps will increase the time-cost efficiency of the entire mission. The RSS team members do not have any prior knowledge about the area where the simulation is taking place and the analysis is fully based on remote sensing satellite data (Landsat, GoogleEarth) and a digital elevation model (ASTER GDEM)from the orbital data. The maps design: The set of maps (covering area 5 km X 5 km centered on the Mission Base Camp) was designed to simplify the process of site selection for the daily traverse planning. Additionally, the maps will help to accommodate the need of the field crew for the increased autonomy in the decision making process, forced by the induced time delay between MSC and "Mars". The set of provided maps should allow the field team to orientate and navigate in the explored areas as well as make informed decisions about choosing the best alternative traverses if the ones suggested by the flight planning team based on satellite data turn out to be impossible. The set of maps includes: A "geological map" prepared following suggestions of [3]. A set of experiment "suitability maps", one for every experiment, assessing the suitability of the area for an experiment. E.g., if a rover cannot move on surfaces that have an inclination larger than 5° and/or are covered with rocks larger than 15 cm in diameter, than the areas likely to have such conditions will be marked as not suitable for this experiment. "Danger" map - showing locations of all potentially dangerous places e.g., cliffs. "Mobility" map - with information important for estimating astronauts' mobility. During the mission maps will be updated on a daily basis, based on the observations made in the field. In this way quality of the maps (and predictions based on them) will be gradually improved. Acknowledges: We thank all people involved in the MARS2013 mission, especially Dr. Gernot Grömer, the President of Austrian Space Forum, MARS2013 program officer & expedition lead. References: [1] Sans Fuentes S.A. 2012. Human-Robotic Mars Science Operations: Target Selection Optimization via Traverse and Science Planning. (M.S. thesis). U. of Innsbruck. [2] Hettich S. 2012. Human-Robotic Mars Science Operations: Itinerary Optimisation for Surface Activities (M.S. thesis). U. of Innsbruck. [3] Skinner J.A.Jr., Fortezzo C.M. 2011. Acta Astronautica. http://dx.doi.org/10.1016/j.actaastro.2011.11.011.
Full Curiosity Traverse Passes One-Mile Mark
2013-08-02
The total distance driven by NASA Mars rover Curiosity passed the one-mile mark a few days before the first anniversary of the rover landing on Mars. The mapped area is within Gale Crater, and north of Mount Sharp, in the middle of the crater.
NASA Technical Reports Server (NTRS)
2004-01-01
[figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1Figure 2
This digital elevation map shows the topography of the 'Columbia Hills,' just in front of the Mars Exploration Rover Spirit's current position. Rover planners have plotted the safest route for Spirit to climb to the front hill, called 'West Spur.' The black line in the middle of the image represents the rover's traverse path, which starts at 'Hank's Hollow' and ends at the top of 'West Spur.' Scientists are sending Spirit up the hill to investigate the interesting rock outcrops visible in images taken by the rover. Data from the Mars Orbital Camera on the orbiting Mars Global Surveyor were used to create this 3-D map. In figure 1, the digital map shows the slopes of the 'Columbia Hills,' just in front of the Mars Exploration Rover Spirit's current position. Colors indicate the slopes of the hills, with red areas being the gentlest and blue the steepest. Rover planners have plotted the safest route for Spirit to climb the front hill, called 'West Spur.' The path is indicated here with a curved black line. Stereo images from the Mars Orbital Camera on the orbiting Mars Global Surveyor were used to create this 3-D map. In figure 2, the map shows the north-facing slopes of the 'Columbia Hills,' just in front of the Mars Exploration Rover Spirit's current position. Bright areas indicate surfaces sloping more toward the north than dark areas. To reach the rock outcrop at the top of the hill, engineers will aim to drive the rover around the dark areas, which would yield less solar power. The curved black line in the middle represents the rover's planned traverse path.NASA Astrophysics Data System (ADS)
Karachevtseva, I. P.; Kozlova, N. A.; Kokhanov, A. A.; Zubarev, A. E.; Nadezhdina, I. E.; Patratiy, V. D.; Konopikhin, A. A.; Basilevsky, A. T.; Abdrakhimov, A. M.; Oberst, J.; Haase, I.; Jolliff, B. L.; Plescia, J. B.; Robinson, M. S.
2017-02-01
The Lunar Reconnaissance Orbiter Camera (LROC) system consists of a Wide Angle Camera (WAC) and Narrow Angle Camera (NAC). NAC images (∼0.5 to 1.7 m/pixel) reveal details of the Luna-21 landing site and Lunokhod-2 traverse area. We derived a Digital Elevation Model (DEM) and an orthomosaic for the study region using photogrammetric stereo processing techniques with NAC images. The DEM and mosaic allowed us to analyze the topography and morphology of the landing site area and to map the Lunokhod-2 rover route. The total range of topographic elevation along the traverse was found to be less than 144 m; and the rover encountered slopes of up to 20°. With the orthomosaic tied to the lunar reference frame, we derived coordinates of the Lunokhod-2 landing module and overnight stop points. We identified the exact rover route by following its tracks and determined its total length as 39.16 km, more than was estimated during the mission (37 km), which until recently was a distance record for planetary robotic rovers held for more than 40 years.
Curiosity Finds Hydrogen-Rich Area of Mars Subsurface
2015-08-19
Curiosity's Russian-made instrument for checking hydration levels in the ground beneath the rover detected an unusually high amount at a site near "Marias Pass," prompting repeated passes over the area to map the hydrogen amounts. The instrument is named Dynamic Albedo of Neutrons, or DAN. It detects hydrogen by the effect of hydrogen atoms on neutrons entering the ground either from cosmic rays and Curiosity's power source (DAN's passive mode) or from the instrument's neutron pulse generator (DAN's active mode). DAN recognizes which neutrons have bounced off hydrogen from their rerduced energy level. This map, covering an area about 130 feet (40 meters) across, shows results from DAN's multiple traverses over the area, with color coding for levels of hydrogen detected. The red coding indicates amounts of hydrogen three to four times as high as the amounts detected anywhere previously along Curiosity's traverse of about 6.9 miles (11.1 kilometers) since landing in August 2012. The inset map at lower right shows the full traverse through Sol 1051 (July 21, 2015), with names assigned to rectangles within Gale Crater for geological mapping purposes. The vertical bar at left indicates the color coding according to counts per second in DAN's passive mode. The hydrogen detected by DAN is interpreted as water molecules or hydroxyl ions bound within minerals or water absorbed onto minerals in the rocks and soil, to a depth of about 3 feet (1 meter) beneath the rover. The amount of hydrogen is often expressed as "water equivalent hydrogen" based on two hydrogen atoms per molecule of water. In the same area where DAN detected an unusually high amount of hydration, Curiosity's Chemistry and Camera (ChemCam) instrument detected an unusually high amount of silica in several rock targets. The DAN and ChemCam findings led to the rover's science team choosing a rock target called "Buckskin" for collection of a drilled sample to be analyzed by the rover's internal laboratory instruments. Russia's Space Research Institute developed DAN in close cooperation with the N.L. Dukhov All-Russia Research Institute of Automatics, Moscow, and the Joint Institute for Nuclear Research, Dubna. The neutron generator development was supervised by the late technical designer German A. Smirnov of the All-Russia Institute of Automatics. Moscow. http://photojournal.jpl.nasa.gov/catalog/PIA19809
Mapping of the Lunokhod-1 Landing Site: A Case Study for Future Lunar Exploration
NASA Astrophysics Data System (ADS)
Karachevtseva, I.; Oberst, J.; Konopikhin, A.; Shingareva, K.; Gusakova, E.; Kokhanov, A.; Baskakova, M.; Peters, O.; Scholten, F.; Wählisch, M.; Robinson, M.
2012-04-01
Introduction. Luna-17 landed on November 17, 1970 and deployed Lunokhod-1, the first remotely operated roving vehicle ever to explore a planetary surface. Within 332 days, the vehicle conquered a traverse of approx. 10 km. The rover was equipped with a navigation camera system as well as a scanner camera with which panoramic images were obtained. From separated stations, stereoscopic views were obtained. The history of the Lunokhods came back into focus recently, when the Lunar Reconnaissance Orbiter [1] obtained images from orbit at highest resolutions of 0.5-0.25 m/pixel. The Luna-17 landing platform as well as the roving vehicles at their final resting positions can clearly be identified. In addition, the rover tracks are clearly visible in most areas. From LRO stereo images, digital elevation model (DEM) of the Lunokhod-1 landing site areas have been derived [2]. These are useful to study the topographic profile and slopes of the traverse. The data are also useful to study the 3-D morphology of craters in the surroundings. Methodology. Lunokhod-1 area mapping have been done using GIS techniques. With CraterTools [3] we digitized craters in the Lunokhod-1 traverse area and created a geodatabase, which consists at this moment of about 45,000 craters including their diameters and depths, obtained from the DEM [4]. The LRO DEM also was used to measure traverse. We used automatic GIS functions for calculating various surface parameters of the Lunokhod-1 area surface including slopes, roughness, crater cumulative and spatial densities, and prepared respective thematic maps. We also measured relative depth (ratio D/H) and inner slopes of craters and classified craters by their morphological type using automatic and visual methods. Vertical profiles through several craters using the high resolution DEM have been done, and the results show good agreement with the topographic models with contours in 10cm that have been obtained from the Lunokhod-1 stereo images [5]. The preliminary results of crater morphology show that highest H/D for studied craters of the Lunokhod 1 area is ~0.14, that is noticeably smaller than that for very fresh well studied small craters, for example, in the Apollo 14 [6]. At present more detailed geomorphology analyses using orthoimages with different illumination is in progress and will be shown at the conference. Conclusions and future works. While new missions to the Lunar surface are being planned, it is of utmost importance to identify and make available for access all Lunar surface data. We show that these data can be used for large-scale mapping and surface studies of landing sites for future lunar missions, for example LUNA-GLOB and LUNA-RESOURCE. Acknowledgments: This research was partly funded by the Ministry of Education and Science of the Russian Federation (MEGA-GRANT, Project name: "Geodesy, cartography and the study of planets and satellites", contract No. 11.G34.31.0021).
The traverse planning process for D-RATS 2010
NASA Astrophysics Data System (ADS)
Hörz, Friedrich; Lofgren, Gary E.; Gruener, John E.; Eppler, Dean B.; Skinner, James A.; Fortezzo, Corey M.; Graf, Jodi S.; Bluethmann, William J.; Seibert, Marc A.; Bell, Ernest R.
2013-10-01
This report describes the traverse planning process for the Desert Research and Technology Studies (D-RATS) 2010 field simulation of a conceptual 14-day planetary mission. This activity took place between August 23 and September 17, 2010 in the San Francisco Volcanic Field, Arizona. It focused on the utilization of two pressurized rovers and a ground-based communication system, as well as on the development of mission operation concepts for long duration, dual-rover missions. The early planning process began some 12 months prior to the actual field tests and defined the first order engineering-, flight operations, and science objectives. The detailed implementation and refinement of these objectives took place over the ensuing 10 months, resulting in a large number of technical and operational constraints that affected the actual traverse route or the cumulative Extravehicular Activity (EVA) time available for detailed field observations. The science planning proceeded from the generation of photogeologic maps of the test area, to the establishment of prioritized science objectives and associated candidate sites for detailed field exploration. The combination of operational constraints and science objectives resulted in the final design of traverse routes and time lines for each of the 24 traverses needed to support 12 field days by two rovers. Examples of daily traverses will be given that will hopefully illustrate that the design of long duration, long distance planetary traverses is a highly interdisciplinary and time-consuming collaboration between diverse engineers, flight operations personnel, human factors interests, and planetary scientists.
Fire-climate interactions in forests of the American Pacific Coast
Valerie Trouet; Alan H. Taylor; Andrew M. Carleton; Carl N. Skinner
2006-01-01
We investigate relationships between climate and wildfire activity between 1929 and 2004 in Pacific coast forests of the United States. Self-Organizing Mapping (SOM) of annual area burned in National Forests (NF) in California, Oregon, and Washington identifies three contiguous NF groups and a fourth group of NF traversed by major highways. Large fire years in all...
Klingebiel, A.A.; Horvath, E.H.; Moore, D.G.; Reybold, W.U.
1987-01-01
Maps showing different classes of slope, aspect, and elevation were developed from U.S. Geological Survey digital elevation model data. The classes were displayed on clear Mylar at 1:24 000-scale and registered with topographic maps and orthophotos. The maps were used with aerial photographs, topographic maps, and other resource data to determine their value in making order-three soil surveys. They were tested on over 600 000 ha in Wyoming, Idaho, and Nevada under various climatic and topographic conditions. Field evaluations showed that the maps developed from digital elevation model data were accurate, except for slope class maps where slopes were <4%. The maps were useful to soil scientists, especially where (i) class boundaries coincided with soil changes, landform delineations, land use and management separations, and vegetation changes, and (ii) rough terrain and dense vegetation made it difficult to traverse the area. In hot, arid areas of sparse vegetation, the relationship of slope classes to kinds of soil and vegetation was less significant.
Chaotic Traversal (CHAT): Very Large Graphs Traversal Using Chaotic Dynamics
NASA Astrophysics Data System (ADS)
Changaival, Boonyarit; Rosalie, Martin; Danoy, Grégoire; Lavangnananda, Kittichai; Bouvry, Pascal
2017-12-01
Graph Traversal algorithms can find their applications in various fields such as routing problems, natural language processing or even database querying. The exploration can be considered as a first stepping stone into knowledge extraction from the graph which is now a popular topic. Classical solutions such as Breadth First Search (BFS) and Depth First Search (DFS) require huge amounts of memory for exploring very large graphs. In this research, we present a novel memoryless graph traversal algorithm, Chaotic Traversal (CHAT) which integrates chaotic dynamics to traverse large unknown graphs via the Lozi map and the Rössler system. To compare various dynamics effects on our algorithm, we present an original way to perform the exploration of a parameter space using a bifurcation diagram with respect to the topological structure of attractors. The resulting algorithm is an efficient and nonresource demanding algorithm, and is therefore very suitable for partial traversal of very large and/or unknown environment graphs. CHAT performance using Lozi map is proven superior than the, commonly known, Random Walk, in terms of number of nodes visited (coverage percentage) and computation time where the environment is unknown and memory usage is restricted.
MER Field Geologic Traverse in Gusev Crater, Mars: Initial Results From the Perspective of Spirit
NASA Technical Reports Server (NTRS)
Crumpler, L.; Cabrol, N.; desMarais, D.; Farmer, J.; Golmbek, M.; Grant, J.; Greely, R.; Grotzinger, J.; Haskin, L.; Arvidson, R.
2004-01-01
This report casts the initial results of the traverse and science investigations by the Mars Exploration Rover (MER) Spirit at Gusev crater [1] in terms of data sets commonly used in field geologic investigations: Local mapping of geologic features, analyses of selected samples, and their location within the local map, and the regional context of the field traverse in terms of the larger geologic and physiographic region. These elements of the field method are represented in the MER characterization of the Gusev traverse by perspective-based geologic/morphologic maps, the placement of the results from Mossbauer, APXS, Microscopic Imager, Mini-TES and Pancam multispectral studies in context within this geologic/ morphologic map, and the placement of the overall traverse in the context of narrow-angle MOC (Mars Orbiter Camera) and descent images. A major campaign over a significance fraction of the mission will be the first robotic traverse of the ejecta from a Martian impact crater along an approximate radial from the crater center. The Mars Exploration Rovers have been conceptually described as 'robotic field geologists', that is, a suite of instruments with mobility that enables far-field traverses to multiple sites located within a regional map/image base at which in situ analyses may be done. Initial results from MER, where the field geologic method has been used throughout the initial course of the investigation, confirm that this field geologic model is applicable for remote planetary surface exploration. The field geologic method makes use of near-field geologic characteristics ('outcrops') to develop an understanding of the larger geologic context through continuous loop of rational steps focused on real-time hypothesis identification and testing. This poster equates 'outcrops' with the locations of in situ investigations and 'regional context' with the geology over distance of several kilometers. Using this fundamental field geologic method, we have identified the basic local geologic materials on the floor of Gusev at this site, their compositions and likely lithologies, origins, processes that have modified these materials, and their potential significance in the interpretation of the regional geology both spatially and temporally.
NASA Astrophysics Data System (ADS)
Forster, R. R.; Miege, C.; Box, J. E.; McConnell, J.; Spikes, V. B.; Burgess, E. W.
2010-12-01
The Greenland Ice Sheet plays an important role in Earth’s climate system evolution. The snow accumulation rate is the largest single mass budget term. With only 14% of the ice sheet area, Southeast Greenland contains the highest accumulation rates, accounting for one third of the total snow accumulation and annual variability. The high accumulation rates have made the region less desirable for long climate record ice cores and therefore, contain relatively very few in situ measurements to constrain the ice sheet mass budget. We present annual snow accumulation rates from the Arctic Circle Traverse 2010 (ACT-10). During April and May 2010 we acquired three 50 m firn cores connected by surface-based 400 MHz ground penetrating radar (GPR) in Southeast Greenland. The traverse repeated and extended the original Arctic Circle Traverse in 2004 (Spikes et al., 2004). Dating is achieved using geochemical analysis of the cores to identify isochronal layers detected by the GPR yielding annual accumulation estimates along the traverse between the core sites. The 300 km ACT-10 GPR snowmobile traverse extended the ACT-04 path 80 km to the lowest elevation core site at 1776 m. Meanwhile, airborne radars, operating as part of NASA’s Operation IceBridge also acquired data over the full length of the ACT-10 path, simultaneously with a portion of the traverse and within days for the remaining segments. The IceBridge and ACT-10 data are to be combined in a calibration effort such that snow accumulation rates may be mapped elsewhere in Greenland and even in Antarctica.
NASA Astrophysics Data System (ADS)
Haase, I.; Oberst, J.; Scholten, F.; Wählisch, M.; Gläser, P.; Karachevtseva, I.; Robinson, M. S.
2012-05-01
Newly acquired high resolution Lunar Reconnaissance Orbiter Camera (LROC) images allow accurate determination of the coordinates of Apollo hardware, sampling stations, and photographic viewpoints. In particular, the positions from where the Apollo 17 astronauts recorded panoramic image series, at the so-called “traverse stations”, were precisely determined for traverse path reconstruction. We analyzed observations made in Apollo surface photography as well as orthorectified orbital images (0.5 m/pixel) and Digital Terrain Models (DTMs) (1.5 m/pixel and 100 m/pixel) derived from LROC Narrow Angle Camera (NAC) and Wide Angle Camera (WAC) images. Key features captured in the Apollo panoramic sequences were identified in LROC NAC orthoimages. Angular directions of these features were measured in the panoramic images and fitted to the NAC orthoimage by applying least squares techniques. As a result, we obtained the surface panoramic camera positions to within 50 cm. At the same time, the camera orientations, North azimuth angles and distances to nearby features of interest were also determined. Here, initial results are shown for traverse station 1 (northwest of Steno Crater) as well as the Apollo Lunar Surface Experiment Package (ALSEP) area.
Curiosity Traverse into Different Terrain
2013-01-15
This image maps the traverse of NASA Mars rover Curiosity from Bradbury Landing to Yellowknife Bay, with an inset documenting a change in the ground thermal properties with arrival at a different type of terrain.
The Lunar Mapping and Modeling Project
NASA Technical Reports Server (NTRS)
Noble, Sarah K.; French, R. A.; Nall, M. E.; Muery, K. G.
2009-01-01
The Lunar Mapping and Modeling Project (LMMP) has been created to manage the development of a suite of lunar mapping and modeling products that support the Constellation Program (CxP) and other lunar exploration activities, including the planning, design, development, test and operations associated with lunar sortie missions, crewed and robotic operations on the surface, and the establishment of a lunar outpost. The information provided through LMMP will assist CxP in: planning tasks in the areas of landing site evaluation and selection, design and placement of landers and other stationary assets, design of rovers and other mobile assets, developing terrain-relative navigation (TRN) capabilities, and assessment and planning of science traverses.
A study of the usefulness of Skylab EREP data for earth resources studies in Australia
NASA Technical Reports Server (NTRS)
Lambert, B. P.; Benson, M. L.; Borough, C. J.; Myers, B. J.; Maffi, C. E.; Simpson, C. J.; Perry, W. J.; Burns, K. L.; Shepherd, J.; Beattie, R. (Principal Investigator)
1975-01-01
The author has identified the following significant results. In subhumid, vegetated areas, S190B photography: (1) has a potentially operational role in detecting lineaments in 1:100,000 scale geological mapping and in major civil engineering surveys; (2) is of limited value for regional lithological mapping at 1:500,000 scale; and (3) provided much useful synoptic information and some detailed information of direct value to the mapping of nonmineral natural resources such as vegetation, land soil, and water. In arid, well exposed areas, S190B photography could be used: (1) with a limited amount of field traverses, to produce reliable 1:500,000 scale geological maps of sedimentary sequences; (2) to update superficial geology on 1:250,000 scale maps; and (3) together with the necessary field studies, to prepare landform, soil, and vegetation maps at 1:1,000,000 scale. Skylab photography was found to be more useful than LANDSAT images for small scale mapping of geology and land types, and for the revision of topographic maps at 1:100,000 scale, because of superior spatial resolution and stereoscopic coverage.
Geologic Map of the North Cascade Range, Washington
Haugerud, Ralph A.; Tabor, Rowland W.
2009-01-01
The North Cascade Range, commonly referred to as the North Cascades, is the northern part of the Cascade Range that stretches from northern California into British Columbia, where it merges with the Coast Mountains of British Columbia at the Fraser River. The North Cascades are generally characterized by exposure of plutonic and metamorphic rocks in contrast to the volcanic terrain to the south. The rocks of the North Cascades are more resistant to erosion, display greater relief, and show evidence of more pronounced uplift and recent glaciation. Although the total length of the North Cascade Range, extending north from Snoqualmie Pass in Washington, is about 200 mi (320 km), this compilation map at 1:200,000 scale covers only that part (~150 mi) in the United States. The compilation map is derived mostly from eight 1:100,000-scale quadrangle maps that include all of the North Cascade Range in Washington and a bit of the mostly volcanic part of the Cascade Range to the south (fig. 1, sheet 2). Overall, the area represented by this compilation is about 12,740 mi2 (33,000 km2). The superb alpine scenery of the North Cascade Range and its proximity to major population centers has led to designation of much of the area for recreational use or wilderness preservation. A major part of the map area is in North Cascade National Park. Other restricted use areas are the Alpine Lakes, Boulder River, Clearwater, Glacier Peak, Henry M. Jackson, Lake Chelan-Sawtooth, Mount Baker, Noisy-Diobsud, Norse Peak, and Pasayten Wildernesses and the Mount Baker, Lake Chelan, and Ross Lake National Recreation Areas. The valleys traversed by Washington State Highway 20 east of Ross Lake are preserved as North Cascades Scenic Highway. The map area is traversed by three major highways: U.S. Interstate 90, crossing Snoqualmie Pass; Washington State Highway 2, crossing Stevens Pass; and Washington State Highway 20, crossing Washington Pass. Major secondary roads, as well as a network of U.S. Forest Service roads and a few private roads mainly used for logging, are restricted mostly to the flanks of the range. Although much of the mountainous core is inaccessible to automobiles, numerous trails serve the foot or horse traveler.
REMOTE-SENSING MINERAL DISCOVERIES IN THE MOJAVE DESERT OF CALIFORNIA.
Raines, Gary L.; Hoover, Donald B.; Collins, William E.
1984-01-01
As a result of remote sensing studies in the Mojave Desert of California three previously unknown stockwork molybdenum systems have been discovered. It is not known if economic deposits of molybdenum and associated minerals occur in these areas; there is, however, sufficient data to judge that these areas are worthy of further exploration. The purpose of this paper is to present case histories of two of these discoveries. These discoveries have been made from laboratory analyses of Landsat multispectral scanner images to map limonitic materials and from field reconnaissance to determine if the limonite is due to hydrothermal alteration. In those areas that seemed most promising, airborne spectrometer surveys were employed to mapped Al-OH minerals, and audio-magnetotelluric (AMT) and telluric-traversing surveys were performed to obtain information at depth.
Processor Would Find Best Paths On Map
NASA Technical Reports Server (NTRS)
Eberhardt, Silvio P.
1990-01-01
Proposed very-large-scale integrated (VLSI) circuit image-data processor finds path of least cost from specified origin to any destination on map. Cost of traversal assigned to each picture element of map. Path of least cost from originating picture element to every other picture element computed as path that preserves as much as possible of signal transmitted by originating picture element. Dedicated microprocessor at each picture element stores cost of traversal and performs its share of computations of paths of least cost. Least-cost-path problem occurs in research, military maneuvers, and in planning routes of vehicles.
NASA Technical Reports Server (NTRS)
2004-01-01
The red dot labeled 'Sol 134-141' in this map illustrates when and where NASA's Mars Exploration Rover Spirit acquired the 'Santa Anita Panorama.' Scientists consider this area, located roughly three-fourths of the way between 'Bonneville Crater' and the base of the 'Columbia Hills,' a treasure trove that may be studied for decades to come. The panorama is one of four 360-degree full panoramas the rover has acquired during its mission. The color thermal inertia data show how well different surface features hold onto heat. Red indicates a high thermal inertia associated with rocky terrain (regions that take longer to warm up and cool down); blue indicates a lower thermal inertia associated with smaller particles and fewer rocks (areas that warm up and cool off quickly). The map comprises background images from the camera on NASA's Mars Global Surveyor orbiter and data from the thermal emission spectrometer on NASA's Mars Odyssey orbiter.2017-10-01
agricultural tractors used on SPoT (Case Corporation and Caterpillar). (Adapted from Lever and Thur 2014.) ................. 2 2 Map showing the 1600...traversed for the first time in 2005 as a proof-of-concept, using a combination of several commercial rubber-tracked agricultural tractors (Caterpillar...traverse route. Inset shows two rubber-tracked, agricultural tractors used on SPoT (Case Corporation and Caterpillar). (Adapted from Lever and Thur 2014
Miller, David M.; Bedford, David R.
2000-01-01
This geologic map database for the El Mirage Lake area describes geologic materials for the dry lake, parts of the adjacent Shadow Mountains and Adobe Mountain, and much of the piedmont extending south from the lake upward toward the San Gabriel Mountains. This area lies within the western Mojave Desert of San Bernardino and Los Angeles Counties, southeastern California. The area is traversed by a few paved highways that service the community of El Mirage, and by numerous dirt roads that lead to outlying properties. An off-highway vehicle area established by the Bureau of Land Management encompasses the dry lake and much of the land north and east of the lake. The physiography of the area consists of the dry lake, flanking mud and sand flats and alluvial piedmonts, and a few sharp craggy mountains. This digital geologic map database, intended for use at 1:24,000-scale, describes and portrays the rock units and surficial deposits of the El Mirage Lake area. The map database was prepared to aid in a water-resource assessment of the area by providing surface geologic information with which deepergroundwater-bearing units may be understood. The area mapped covers the Shadow Mountains SE and parts of the Shadow Mountains, Adobe Mountain, and El Mirage 7.5-minute quadrangles. The map includes detailed geology of surface and bedrock deposits, which represent a significant update from previous bedrock geologic maps by Dibblee (1960) and Troxel and Gunderson (1970), and the surficial geologic map of Ponti and Burke (1980); it incorporates a fringe of the detailed bedrock mapping in the Shadow Mountains by Martin (1992). The map data were assembled as a digital database using ARC/INFO to enable wider applications than traditional paper-product geologic maps and to provide for efficient meshing with other digital data bases prepared by the U.S. Geological Survey's Southern California Areal Mapping Project.
Wheeler, George Montague
1874-01-01
2d. A chapter upon the special subjects of mining, agriculture, irrigation, routes of communication, Indians, &c., to conclude with a project for the surveys contemplated for the ensuing season; the whole to be accompanied by appendixes, containing reports of certain officers and civilian assistants, and a, map upon which are delineated the areas of territory west of the one hundredth meridian yet unsurveyed instrumentally, and the relation to them of lines and areas traversed and mapped by exploration and survey parties under the auspices of the War Department, so far as the exhibit can be prepared at the office of the survey.
Morphology and texture of particles along the Spirit rover traverse from sol 450 to sol 745
NASA Astrophysics Data System (ADS)
Yingst, R. A.; Crumpler, L.; Farrand, W. H.; Li, R.; Cabrol, N. A.; Neakrase, L. D.
2008-12-01
We quantified and classified the shape, roundness, size, and texture of 935 loose surface particles along the Spirit rover traverse from sols 450-745 to assess origin, transport, and other alteration mechanisms that altered particles during and after formation. Variation in particle morphologic parameters along traverse is consistent with crossing mapped geologic unit boundaries. Texture is divided into four types: vesicular, smooth and flat-faceted, rough and flat-faceted, and very rough. Sphericity and roundness are intermediate and low, respectively, comparable to particles moved by high-energy transport or to crushed particles. This indicates intermittent, high-energy emplacement or modification of a single lithology, rather than systematic, continuous low-energy abrasion or wear over time. Comparison with particle morphology at other Mars landing sites is consistent with the hypothesis that no secondary systematic transport or wide-scale chemical alteration was active at a significant enough level to alter macromorphology. In particular, particle morphology at the Mars Pathfinder site shows stronger evidence of abrasion than along the Spirit traverse, suggesting Mars Pathfinder particles have undergone abrasion processes that particles in this study area have not. Additionally, morphology indices have correlation coefficients near zero, indicating that a fluvial transport mechanism is likely not responsible for morphology. Morphology and texture are instead related to origin and composition rather than subsequent modification. Morphology and texture support a volcanic origin, possibly without modification, but most likely altered primarily by ballistic impact, implying that the Spirit landing site and traverse may be utilized in the future as a standard site for characterization of impact-derived morphology.
Lunar Reconnaissance Orbiter Camera
them out » Traverse featurette Traverse the Apollo Landing Sites & More. By combining LROC imagery , data, and historical data, we've created detailed, interactive maps of the Apollo Landing Sites and taken by the original Apollo crews. ASU maintains the Apollo Digital Image Archive and the March to the
Where Boron? Mars Rover Detects It
2016-12-13
This map shows the route driven by NASA's Curiosity Mars rover (blue line) and locations where the rover's Chemistry and Camera (ChemCam) instrument detected the element boron (dots, colored by abundance of boron according to the key at right). The main map shows the traverse from landing day (Sol 0) in August 2012 to the rover's location in September 2016, with boron detections through September 2015. The inset at upper left shows a magnified version of the most recent portion of that traverse, with boron detections during that portion. Overlapping dots represent cases when boron was detected in multiple ChemCam observation points in the same target and non-overlapping dots represent cases where two different targets in the same location have boron. Most of the mission's detections of boron have been made in the most recent seven months (about 200 sols) of the rover's uphill traverse. The base image for the map is from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. North is up. The scale bar at lower right represents one kilometer (0.62 mile). http://photojournal.jpl.nasa.gov/catalog/PIA21150
Autonomous Navigation Results from the Mars Exploration Rover (MER) Mission
NASA Technical Reports Server (NTRS)
Maimone, Mark; Johnson, Andrew; Cheng, Yang; Willson, Reg; Matthies, Larry H.
2004-01-01
In January, 2004, the Mars Exploration Rover (MER) mission landed two rovers, Spirit and Opportunity, on the surface of Mars. Several autonomous navigation capabilities were employed in space for the first time in this mission. ]n the Entry, Descent, and Landing (EDL) phase, both landers used a vision system called the, Descent Image Motion Estimation System (DIMES) to estimate horizontal velocity during the last 2000 meters (m) of descent, by tracking features on the ground with a downlooking camera, in order to control retro-rocket firing to reduce horizontal velocity before impact. During surface operations, the rovers navigate autonomously using stereo vision for local terrain mapping and a local, reactive planning algorithm called Grid-based Estimation of Surface Traversability Applied to Local Terrain (GESTALT) for obstacle avoidance. ]n areas of high slip, stereo vision-based visual odometry has been used to estimate rover motion, As of mid-June, Spirit had traversed 3405 m, of which 1253 m were done autonomously; Opportunity had traversed 1264 m, of which 224 m were autonomous. These results have contributed substantially to the success of the mission and paved the way for increased levels of autonomy in future missions.
Tile prediction schemes for wide area motion imagery maps in GIS
NASA Astrophysics Data System (ADS)
Michael, Chris J.; Lin, Bruce Y.
2017-11-01
Wide-area surveillance, traffic monitoring, and emergency management are just several of many applications benefiting from the incorporation of Wide-Area Motion Imagery (WAMI) maps into geographic information systems. Though the use of motion imagery as a GIS base map via the Web Map Service (WMS) standard is not a new concept, effectively streaming imagery is particularly challenging due to its large scale and the multidimensionally interactive nature of clients that use WMS. Ineffective streaming from a server to one or more clients can unnecessarily overwhelm network bandwidth and cause frustratingly large amounts of latency in visualization to the user. Seamlessly streaming WAMI through GIS requires good prediction to accurately guess the tiles of the video that will be traversed in the near future. In this study, we present an experimental framework for such prediction schemes by presenting a stochastic interaction model that represents a human user's interaction with a GIS video map. We then propose several algorithms by which the tiles of the stream may be predicted. Results collected both within the experimental framework and using human analyst trajectories show that, though each algorithm thrives under certain constraints, the novel Markovian algorithm yields the best results overall. Furthermore, we make the argument that the proposed experimental framework is sufficient for the study of these prediction schemes.
NASA Technical Reports Server (NTRS)
2005-01-01
[figure removed for brevity, see original site] Annotated Spirit Traverse Map This image shows the route that NASA's Mars Exploration Rover Spirit has driven inside Gusev Crater from its first Martian day (sol 1) to its 680th sol (Dec. 1, 2005), more than a complete Martian year. The underlying image (previously released as PIA07849) is a mosaic of images from the Mars Orbiter Camera on NASA's Mars Global Surveyor orbiter. The scale bar at lower left is 500 meters (0.31 mile). As of sol 680, Spirit had driven a total of 5,495 meters (3.41 miles).NASA Technical Reports Server (NTRS)
2004-01-01
This false-color panoramic camera composite traverse map depicts the Mars Exploration Rover Spirit's journey since landing at Gusev Crater, Mars. It was generated from three of the camera's different wavelength filters (750 nanometers, 530 nanometers and 480 nanometers). This map was created on the 65th martian day, or sol, of Spirit's mission, after Spirit had traveled 328 meters (1076 feet) from its lander to the rim of the crater dubbed 'Bonneville.' From this high point, Spirit was able to capture with its panoramic camera the entire rover traverse. The map points out major stops that Spirit made along the way, including features nicknamed 'Adirondack;' 'Stone Council;' 'Laguna Hollow;' and 'Humphrey.' Also highlighted is the landscape feature informally named 'Grissom Hill' and Spirit's landing site, the Columbia Memorial Station.
NASA Astrophysics Data System (ADS)
Bouiflane, Mustapha; Manar, Ahmed; Medina, Fida; Youbi, Nasrrddine; Rimi, Abdelkrim
2017-06-01
A high-resolution aeromagnetic survey was carried out in the Anti- Atlas, Morocco covering the main areas traversed by the Great CAMP Foum Zguid dyke (FZD). This ;doleritic; dyke belongs to the Central Atlantic Magmatic Province (CAMP), a Large Igneous Province which is associated with the fragmentation of the supercontinent Pangaea and the initial stages of rifting of the Central Atlantic Ocean. It also coincides in time with the mass extinction of the Triassic - Jurassic boundary. Based on the study of geological maps and Google Earth satellite images, it appears that the FZD is poorly exposed and, often covered by Quaternary deposits. This work proposes aeromagnetic modelling and interpretation of the FZD in order to better constrain its structural extent. The data have allowed (i) mapping of the dyke over great distances, under the Quaternary deposits and through areas where it was poorly characterized on the geological map; (ii) identifying major tectonic lineaments interpreted as faults; (iii) recognizing magnetic anomalies related to mafic intrusive bodies; and (iv) informing about regional structural context.
NEEMO 15: Evaluation of Human Exploration Systems for Near-Earth Asteroids
NASA Technical Reports Server (NTRS)
Chappell, Steven P.; Gernhardt, Michael L.
2011-01-01
The NASA Extreme Environment Mission Operations (NEEMO) 15 mission was focused on near-Earth Asteroid (NEA) exploration techniques evaluation. It began with a University of Delaware autonomous underwater vehicle (AUV) systematically mapping the coral reef for hundreds of meters surrounding the Aquarius habitat. This activity is akin to the type of "far field survey" approach that may be used by a robotic precursor in advance of a human mission to a NEA. Data from the far-field survey were then examined by the NEEMO science team and follow-up exploration traverses were planned, which used Deepworker single-person submersibles. Science traverses at NEEMO 15 were planned according to a prioritized list of scientific objectives developed by the science team based on review and discussion of previous related marine science research including previous marine science saturation missions conducted at the Aquarius habitat. AUV data was used to select several areas of scientific interest. The Deepworker science traverses were then executed at these areas of interest during 4 days of the NEEMO 15 mission and provided higher resolution data such as coral species distribution and mortality. These traverses are analogous to the "near field survey" approach that is expected to be performed by a multi mission space exploration vehicle (MMSEV) during a human mission to a NEA before conducting extravehicular activities (EVA)s. In addition to the science objectives that were pursued, the NEEMO 15 science traverses provided an opportunity to test newly developed software and techniques. Sample collection and instrument deployment on the NEA surface by EVA crew would follow the "near field survey" in a human NEA mission. Sample collection was not necessary for the purposes of the NEEMO science objectives; however, the engineering and operations objectives during NEEMO 15 were to evaluate different combinations of vehicles, crewmembers, tools, and equipment that could be used to perform these tasks on a NEA. Specifically, the productivity and acceptability of simulated NEA exploration activities were systematically quantified and compared when operating with different combinations of crew sizes and exploration systems including MMSEVs, EVA jet packs, and EVA translation devices.
Remote image analysis for Mars Exploration Rover mobility and manipulation operations
NASA Technical Reports Server (NTRS)
Leger, Chris; Deen, Robert G.; Bonitz, Robert G.
2005-01-01
NASA's Mars Exploration Rovers are two sixwheeled, 175-kg robotic vehicles which have operated on Mars for over a year as of March 2005. The rovers are controlled by teams who must understand the rover's surroundings and develop command sequences on a daily basis. The tight tactical planning timeline and everchanging environment call for tools that allow quick assessment of potential manipulator targets and traverse goals, since command sequences must be developed in a matter of hours after receipt of new data from the rovers. Reachability maps give a visual indication of which targets are reachable by each rover's manipulator, while slope and solar energy maps show the rover operator which terrain areas are safe and unsafe from different standpoints.
UGV technology for urban environments
NASA Astrophysics Data System (ADS)
Christensen, Henrik I.; Folkeson, John; Hedstrom, Andreas; Lundberg, Carl
2004-09-01
Deployment of humans in an urban setting for search and rescue type missions poses a major risk to the personnel. In rescue missions the risk can stem from debris, gas, etc. and in a strategic setting the risk can stem from snipers, mines, gas, etc. There is consequently a natural interest in studies of how UGV technology can be deployed for tasks such as reconnaissance, retrieval of objects (bombs, injured people, etc.). Today most vehicles used by the military and bomb squads are tele-operated and without any autonomony. This implies that operation of the vehicles is a stressful and demanding task. Part of this stress can be removed through introduction of autonomous functionality. Autonomy implicitly requires use of map information to allow the system to localize and traverse a particular area in addition autonomous mapping of an area is a valuable functionality as part of reconnaissance missions to provide an initial inventory of a new area. A host of different sensory modalities can be used for mapping. In general no single modality is, however, sufficient for robust and efficient mapping. In the present study GPS, Inertial Cues, Laser ranging and Odometry is used for simultaneous mapping and localization in urban environments. The mapping is carried out autonomously using a coverage strategy to ensure full mapping of a particular area. In relation to mapping another important issue is the design of an efficient user interface that allows a regular rescue worker, or a soldier, to operate the vehicle without detailed knowledge about robotics. A number of different designs for user interfaces will be presented and results from studies with a range of end-users (soldiers) will also be reported. The complete system has been tested in an urban warfare facility outside of Stockholm. Detailed results will be reposted from two different test facilities.
Geologic map of the east half of the Lime Hills 1:250,000-scale quadrangle, Alaska
Gamble, Bruce M.; Reed, Bruce L.; Richter, Donald H.; Lanphere, Marvin A.
2013-01-01
This map is compiled from geologic mapping conducted between 1985 and 1992 by the U.S. Geological Survey as part of the Alaska Mineral Resource Assessment Program. That mapping built upon previous USGS work (1963–1988) unraveling the magmatic history of the Alaska–Aleutian Range batholith. Quaternary unit contacts depicted on this map are derived largely from aerial-photograph interpretation. K-Ar ages made prior to this study have been recalculated using 1977 decay constants. The east half of the Lime Hills 1:250,000-scale quadrangle includes part of the Alaska–Aleutian Range batholith and several sequences of sedimentary rocks or mixed sedimentary and volcanic rocks. The Alaska–Aleutian Range batholith contains rocks that represent three major igneous episodes, (1) Early and Middle Jurassic, (2) Late Cretaceous and early Tertiary, and (3) middle Tertiary; only rocks from the latter two episodes are found in this map area. The map area is one of very steep and rugged terrain; elevations range from a little under 1,000 ft (305 m) to 9,828 ft (2,996 m). Foot traverses are generally restricted to lowermost elevations. Areas suitable for helicopter landings can be scarce at higher elevations. Most of the area was mapped from the air, supplemented by direct examination of rocks where possible. This restricted access greatly complicates understanding some of the more complex geologic units. For example, we know there are plutons whose compositions vary from gabbro to granodiorite, but we have little insight as to how these phases are distributed and what their relations might be to each other. It is also possible that some of what we have described as compositionally complex plutons might actually be several distinct intrusions.
Route-choice modeling using GPS-based travel surveys.
DOT National Transportation Integrated Search
2013-06-01
The advent of GPS-based travel surveys offers an opportunity to develop empirically-rich route-choice models. However, the GPS traces must first be mapped to the roadway network, map-matching, to identify the network-links actually traversed. For thi...
Zhou, Lihong; Yuan, Liming; Thomas, Rick; Iannacchione, Anthony
2017-12-01
When there are installations of air velocity sensors in the mining industry for real-time airflow monitoring, a problem exists with how the monitored air velocity at a fixed location corresponds to the average air velocity, which is used to determine the volume flow rate of air in an entry with the cross-sectional area. Correction factors have been practically employed to convert a measured centerline air velocity to the average air velocity. However, studies on the recommended correction factors of the sensor-measured air velocity to the average air velocity at cross sections are still lacking. A comprehensive airflow measurement was made at the Safety Research Coal Mine, Bruceton, PA, using three measuring methods including single-point reading, moving traverse, and fixed-point traverse. The air velocity distribution at each measuring station was analyzed using an air velocity contour map generated with Surfer ® . The correction factors at each measuring station for both the centerline and the sensor location were calculated and are discussed.
Yuan, Liming; Thomas, Rick; Iannacchione, Anthony
2017-01-01
When there are installations of air velocity sensors in the mining industry for real-time airflow monitoring, a problem exists with how the monitored air velocity at a fixed location corresponds to the average air velocity, which is used to determine the volume flow rate of air in an entry with the cross-sectional area. Correction factors have been practically employed to convert a measured centerline air velocity to the average air velocity. However, studies on the recommended correction factors of the sensor-measured air velocity to the average air velocity at cross sections are still lacking. A comprehensive airflow measurement was made at the Safety Research Coal Mine, Bruceton, PA, using three measuring methods including single-point reading, moving traverse, and fixed-point traverse. The air velocity distribution at each measuring station was analyzed using an air velocity contour map generated with Surfer®. The correction factors at each measuring station for both the centerline and the sensor location were calculated and are discussed. PMID:29201495
Opportunity's Travels During its First 205 Martian Days
NASA Technical Reports Server (NTRS)
2004-01-01
This map shows the traverse of NASA's Mars Exploration Rover Opportunity through the rover's 205th martian day, or sol (Aug. 21, 2004). The background image is from the rover's descent imaging camera. Images inset along the route are from Opportunity's navigation camera. Opportunity began its exploration inside 'Eagle' crater near the left edge of the map. Following completion of its study of the outcrop there, it traversed eastward to a small crater ('Fram' crater) before driving southeastward to the rim of 'Endurance' crater. After a survey partly around the south rim of Endurance crater, Opportunity drove inside the southwest rim of Endurance crater and began a systematic study of outcrops exposed on the crater's inner slope.Mineral reconnaissance of the southern part of the Wadi Qaraqir quadrangle, Saudi Arabia
Johnson, Robert Francis; Trent, Virgil A.
1972-01-01
Introduction At the end of a field trip to the Wadi as Surr quadrangle (Johnson and Trent, 1967) a few days were spent in the southern part of the adjoinning Wadi Qaraqir quadrangle in order to extend our mineral reconnaissance as far east as the Arabian Plateau. The area examine is shown by the distribution of sample localities on the accompanying map. No mineral deposits of economic interest were seen. The terrain is one of broad plains and low hills that extend westward from the base of a prominent erosional scarp which forms the western edge of the Arabian Plateau. Streams cutting headward into the low-dipping massive sandstone of the Plateau have carved deep canyongs with vertical walls, and outliers of the sandstone are preserved as buttes and erosional forms of varied shapes. There are no permanent settlements in the mapped areas. The one road leads up a tributary of Wadi Qaraqir to some date gardens at the base of the sandstone cliffs. A well-travelled caravan route crosses the passes at Al Khuraytah to reach the Plateau H. St. John Philby strongly recommended that a road be constructed through these passes to provide direct access from Tabuk to the Red Sea coast. Burton (1878) was probably the first European to visit the area. He was searching for mineral deposits and he also located some Nabatcan ruins. Philby in company with R. G. Bogue, U. S. Geological Survey, explored the scarp in the Wadi Qaraqir valley and drove northwestward to Al Khuraytah pass. The geology of the Wadi Qaraqir quadrangle shown on the geologic map of the Northwestern Hijaz (Brown and others, 1963) was compiled from Bogue's work. Our work consisted of making traverses around the hilly area and up accessible wadis. We examined the rocks along the traverse routes and visited target areas that had been selected by examination of aerial photographs. Samples of wadi sediment were collected from fault zones, granite contacts, and areas that showed some evidence of hydrothermal alteration. The work was made possible by the cooperation fo the officials of the Directorate General of Mineral Resources, Ministry of Petroleum and Mineral Resources, who arranged for vehicles and accompanying personnel. We did not have a counterpart Saudi geologist for this portion of our trip.
Drawing out the Resistance Narrative via Mapping in "The Selected Works of T. S. Spivet"
ERIC Educational Resources Information Center
Hameed, Alya
2017-01-01
Though many children's texts include maps that visually demarcate their journeys, modern texts rarely involve active mapping by child characters themselves, suggesting that children cannot (or should not) conceptualise the world for themselves, but require an adult's guidance to traverse it. Reif Larsen's "The Selected Works of T. S.…
Familiar route loyalty implies visual pilotage in the homing pigeon
Biro, Dora; Meade, Jessica; Guilford, Tim
2004-01-01
Wide-ranging animals, such as birds, regularly traverse large areas of the landscape efficiently in the course of their local movement patterns, which raises fundamental questions about the cognitive mechanisms involved. By using precision global-positioning-system loggers, we show that homing pigeons (Columba livia) not only come to rely on highly stereotyped yet surprisingly inefficient routes within the local area but are attracted directly back to their individually preferred routes even when released from novel sites off-route. This precise route loyalty demonstrates a reliance on familiar landmarks throughout the flight, which was unexpected under current models of avian navigation. We discuss how visual landmarks may be encoded as waypoints within familiar route maps. PMID:15572457
Lidar-enhanced geologic mapping, examples from the Medford and Hood River areas, Oregon
NASA Astrophysics Data System (ADS)
Wiley, T. J.; McClaughry, J. D.
2012-12-01
Lidar-based 3-foot digital elevation models (DEMs) and derivatives (slopeshade, hillshade, contours) were used to help map geology across 1700 km2 (650 mi2) near Hood River and Medford, Oregon. Techniques classically applied to interpret coarse DEMs and small-scale topographic maps were adapted to take advantage of lidar's high resolution. Penetration and discrimination of plant cover by the laser system allowed recognition of fine patterns and textures related to underlying geologic units and associated soils. Surficial geologic maps were improved by the ability to examine tiny variations in elevation and slope. Recognition of low-relief features of all sizes was enhanced where pixel elevation ranges of centimeters to meters, established by knowledge of the site or by trial, were displayed using thousands of sequential colors. Features can also be depicted relative to stream level by preparing a DEM that compensates for gradient. Near Medford, lidar-derived contour maps with 1- to 3-foot intervals revealed incised bajada with young, distal lobes defined by concentric contour lines. Bedrock geologic maps were improved by recognizing geologic features associated with surface textures and patterns or topographic anomalies. In sedimentary and volcanic terrain, structure was revealed by outcrops or horizons lying at one stratigraphic level. Creating a triangulated irregular network (TIN) facet from positions of three or more such points gives strike and dip. Each map area benefited from hundreds of these measurements. A more extensive DEM in the plane of the TIN facet can be subtracted from surface elevation (lidar DEM) to make a DEM with elevation zero where the stratigraphic horizon lies at the surface. The distribution of higher and lower stratigraphic horizons can be shown by highlighting areas similarly higher or lower on the same DEM. Poor fit of contacts or faults projected between field traverses suggest the nature and amount of intervening geologic structure. Intrusive bodies were locally delimited by linear mounds where contact metamorphism hardened soft, fractured country rock. Bedrock faults were revealed where fault traces formed topographic anomalies or where topography associated with stratigraphic horizons or bedding-parallel textural fabrics was offset. This was important for identification of young faults and associated earthquake hazards. Previously unknown Holocene faults southwest of Hood River appear as subtle lineaments redirecting modern drainages or offsetting glacial moraines or glaciated bedrock. West of Medford, the presence young faulting was confirmed by elevation data that showed bedrock in the channel of the Rogue River at higher elevations below Gold Ray dam than in boreholes upstream. Such obscure structural features would have gone unrecognized using traditional topographic analysis or field reconnaissance. Fieldwork verified that lidar techniques improved our early geologic models, resolution of geologic features, and mapping of surficial and bedrock geology between traverses.
Traverse Planning Experiments for Future Planetary Surface Exploration
NASA Technical Reports Server (NTRS)
Hoffman, S. J.; Voels, S. A.; Mueller, R. P.; Lee, P. C.
2011-01-01
This paper describes the results of a recent (July-August 2010 and July 2011) planetary surface traverse planning experiment. The purpose of this experiment was to gather data relevant to robotically repositioning surface assets used for planetary surface exploration. This is a scenario currently being considered for future human exploration missions to the Moon and Mars. The specific scenario selected was a robotic traverse on the lunar surface from an outpost at Shackleton Crater to the Malapert Massif. As these are exploration scenarios, the route will not have been previously traversed and the only pre-traverse data sets available will be remote (orbital) observations. Devon Island was selected as an analog location where a traverse route of significant length could be planned and then traveled. During the first half of 2010, a team of engineers and scientists who had never been to Devon Island used remote sensing data comparable to that which is likely to be available for the Malapert region (eg., 2-meter/pixel imagery, 10-meter interval topographic maps and associated digital elevation models, etc.) to plan a 17-kilometer (km) traverse. Surface-level imagery data was then gathered on-site that was provided to the planning team. This team then assessed whether the route was actually traversable or not. Lessons learned during the 2010 experiment were then used in a second experiment in 2011 for which a much longer traverse (85 km) was planned and additional surface-level imagery different from that gathered in 2010 was obtained for a comparative analysis. This paper will describe the route planning techniques used, the data sets available to the route planners and the lessons learned from the two traverses planned and carried out on Devon Island.
Mapping High Biomass Corridors for Climate and Biodiversity Co-Benefits
NASA Astrophysics Data System (ADS)
Jantz, P.; Goetz, S. J.; Laporte, N. T.
2013-12-01
A key issue in global conservation is how climate mitigation activities can secure biodiversity co-benefits. Tropical deforestation releases significant amounts of CO2 to the atmosphere and results in widespread biodiversity loss. The dominant strategy for forest conservation has been protected area designation. However, maintaining biodiversity in protected areas requires ecological exchange with ecosystems in which they are embedded. At current funding levels, existing conservation strategies are unlikely to prevent further loss of connectivity between protected areas and surrounding landscapes. The emergence of REDD+, a mechanism for funding carbon emissions reductions from deforestation in developing countries, suggests an alignment of goals and financial resources for protecting forest carbon, maintaining biodiversity in protected areas, and minimizing loss of forest ecosystem services. Identifying, protecting and sustainably managing vegetation carbon stocks between protected areas can provide both climate mitigation benefits through avoided CO2 emissions from deforestation and biodiversity benefits through the targeted protection of forests that maintain connectivity between protected areas and surrounding ecosystems. We used a high resolution, pan-tropical map of vegetation carbon stocks derived from MODIS, GLAS lidar and field measurements to map corridors that traverse areas of highest aboveground biomass between protected areas. We mapped over 13,000 corridors containing 49 GtC, accounting for 14% of unprotected vegetation carbon stock in the tropics. In the majority of cases, carbon density in corridors was commensurate with that of the protected areas they connect, suggesting significant opportunities for achieving climate mitigation and biodiversity co-benefits. To further illustrate the utility of this approach, we conducted a multi-criteria analysis of corridors in the Brazilian Amazon, identifying high biodiversity, high vegetation carbon stock corridors with low opportunity costs which may be good candidates for inclusion in climate mitigation activities like those being considered under REDD+.
27 CFR 9.114 - Old Mission Peninsula.
Code of Federal Regulations, 2011 CFR
2011-04-01
... boundary in Grand Traverse County, Michigan, consists of all of Peninsula Township, excluding Marion and Bassett Islands. In addition, the viticultural area takes in a small portion of Traverse City Township. (1... Grand Traverse Bay at Section 1, Township 27 North, Range 11 West (T27N, R11W), approximately 500 feet...
27 CFR 9.114 - Old Mission Peninsula.
Code of Federal Regulations, 2010 CFR
2010-04-01
... boundary in Grand Traverse County, Michigan, consists of all of Peninsula Township, excluding Marion and Bassett Islands. In addition, the viticultural area takes in a small portion of Traverse City Township. (1... Grand Traverse Bay at Section 1, Township 27 North, Range 11 West (T27N, R11W), approximately 500 feet...
30 CFR 75.1200-1 - Additional information on mine map.
Code of Federal Regulations, 2010 CFR
2010-07-01
... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Maps § 75.1200-1 Additional... symbols; (g) The location of railroad tracks and public highways leading to the mine, and mine buildings... permanent base line points coordinated with the underground and surface mine traverses, and the location and...
33 CFR 110.82a - Little Traverse Bay, Lake Michigan, Harbor Springs, Mich.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Little Traverse Bay, Lake Michigan, Harbor Springs, Mich. 110.82a Section 110.82a Navigation and Navigable Waters COAST GUARD... Traverse Bay, Lake Michigan, Harbor Springs, Mich. (a) Area 1. Beginning at latitude 45°25′42.2″ N...
33 CFR 110.82a - Little Traverse Bay, Lake Michigan, Harbor Springs, Mich.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Little Traverse Bay, Lake Michigan, Harbor Springs, Mich. 110.82a Section 110.82a Navigation and Navigable Waters COAST GUARD... Traverse Bay, Lake Michigan, Harbor Springs, Mich. (a) Area 1. Beginning at latitude 45°25′42.2″ N...
33 CFR 110.82a - Little Traverse Bay, Lake Michigan, Harbor Springs, Mich.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Little Traverse Bay, Lake Michigan, Harbor Springs, Mich. 110.82a Section 110.82a Navigation and Navigable Waters COAST GUARD... Traverse Bay, Lake Michigan, Harbor Springs, Mich. (a) Area 1. Beginning at latitude 45°25′42.2″ N...
33 CFR 110.82a - Little Traverse Bay, Lake Michigan, Harbor Springs, Mich.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Little Traverse Bay, Lake Michigan, Harbor Springs, Mich. 110.82a Section 110.82a Navigation and Navigable Waters COAST GUARD... Traverse Bay, Lake Michigan, Harbor Springs, Mich. (a) Area 1. Beginning at latitude 45°25′42.2″ N...
33 CFR 110.82a - Little Traverse Bay, Lake Michigan, Harbor Springs, Mich.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Little Traverse Bay, Lake Michigan, Harbor Springs, Mich. 110.82a Section 110.82a Navigation and Navigable Waters COAST GUARD... Traverse Bay, Lake Michigan, Harbor Springs, Mich. (a) Area 1. Beginning at latitude 45°25′42.2″ N...
Photogrammetry using Apollo 16 orbital photography, part B
NASA Technical Reports Server (NTRS)
Wu, S. S. C.; Schafer, F. J.; Jordan, R.; Nakata, G. M.
1972-01-01
Discussion is made of the Apollo 15 and 16 metric and panoramic cameras which provided photographs for accurate topographic portrayal of the lunar surface using photogrammetric methods. Nine stereoscopic models of Apollo 16 metric photographs and three models of panoramic photographs were evaluated photogrammetrically in support of the Apollo 16 geologic investigations. Four of the models were used to collect profile data for crater morphology studies; three models were used to collect evaluation data for the frequency distributions of lunar slopes; one model was used to prepare a map of the Apollo 16 traverse area; and one model was used to determine elevations of the Cayley Formation. The remaining three models were used to test photogrammetric techniques using oblique metric and panoramic camera photographs. Two preliminary contour maps were compiled and a high-oblique metric photograph was rectified.
Visual terrain mapping for traversable path planning of mobile robots
NASA Astrophysics Data System (ADS)
Shirkhodaie, Amir; Amrani, Rachida; Tunstel, Edward W.
2004-10-01
In this paper, we have primarily discussed technical challenges and navigational skill requirements of mobile robots for traversability path planning in natural terrain environments similar to Mars surface terrains. We have described different methods for detection of salient terrain features based on imaging texture analysis techniques. We have also presented three competing techniques for terrain traversability assessment of mobile robots navigating in unstructured natural terrain environments. These three techniques include: a rule-based terrain classifier, a neural network-based terrain classifier, and a fuzzy-logic terrain classifier. Each proposed terrain classifier divides a region of natural terrain into finite sub-terrain regions and classifies terrain condition exclusively within each sub-terrain region based on terrain visual clues. The Kalman Filtering technique is applied for aggregative fusion of sub-terrain assessment results. The last two terrain classifiers are shown to have remarkable capability for terrain traversability assessment of natural terrains. We have conducted a comparative performance evaluation of all three terrain classifiers and presented the results in this paper.
Behrendt, John C.
2007-01-01
When 12 countries established scientific stations in Antarctica for the 1957-58 (IGY), the Cold War was at its height, seven countries had made claims in Antarctica, and the Antarctic Treaty was in the future. The only major field project of the U.S. IGY Antarctic program was series of oversnow traverses, starting in 1957, making seismic reflection ice soundings (and other geophysical measurements) and glaciological studies. The U.S.S.R. and France made similar traverses coordinated through the IGY. Although geology and topographic mapping were not part of the IGY program because of the claims issue and the possibility of mineral resources, the oversnow traverse parties did geologic work, during which unknown mountains were discovered. The oversnow traverses continued through 1966 and resulted in an excellent first approximation of the snow surface elevation, ice thickness and bed topography of Antarctica, as well as the mean annual temperature of that era and snow accumulation.
McLaughlin, R.J.; Sarna-Wojicki, A. M.; Fleck, R.J.; Wright, W.H.; Levin, V.R.G.; Valin, Z.C.
2004-01-01
The purpose of this geologic map is to provide a context within which to interpret the Neogene evolution of the active strike-slip fault system traversing the Mark West Springs 7.5' quadrangle and adjacent areas. Based on this geologic framework, the timing and total amounts of displacement and the Neogene rates of slip for faults of the right-stepover area between the Healdsburg and Maacama Faults are addressed.The Mark West Springs quadrangle is located in the northern California Coast Ranges north of San Francisco Bay. It is underlain by Mesozoic rocks of the Franciscan Complex, the Coast Range ophiolite, and the Great Valley sequence, considered here to be the pre-Tertiary basement of the northern Coast Ranges. These rocks are overlain by a complexly interstratified and mildly to moderately deformed sequence of Pleistocene to late Miocene marine and nonmarine sedimentary and largely subaerial volcanic rocks. These rocks and unconformably overlying, less-deformed Holocene and Pleistocene strata are cut by the active right-lateral Healdsburg and Maacama Fault Zones.Mapping of the Mark West Springs quadrangle began in 1996 and was completed in October 2002. Most of the mapping presented here is original, although a few other sources of existing geologic mapping were also utilized. Funding for the project was provided by the National Cooperative Geologic Mapping and Earthquake Hazards Reduction programs of the U.S. Geological Survey, in cooperation with geologic hazards mapping investigations of the California Geological Survey.
1979-05-01
White Rock Dam Recreation Area 25 Reservation Highway Recreation Area 27 Brown’s Valley Dike Recreation Area 28 Potential Recreation Areas 28 Section...Development 35 White Rock Dam 35 Reservation Highway 39 Brown’s Valley Dike 39 Land Use Allocation 42 Project Operations ൲ Operations: Recreation--Intensive...Facilities 4 Proposed Facilities v i i u < *1 I_ • In I . .. PROJECT DAT ~PROJECT DATA LAKE TRAVERSE AND RESERVATION DAM Reservoir Flowage rights to
NASA Astrophysics Data System (ADS)
Arvidson, R. E.; Squyres, S. W.; Baumgartner, E. T.; Schenker, P. S.; Niebur, C. S.; Larsen, K. W.; SeelosIV, F. P.; Snider, N. O.; Jolliff, B. L.
2002-08-01
The Field Integration Design and Operations (FIDO) prototype Mars rover was deployed and operated remotely for 2 weeks in May 2000 in the Black Rock Summit area of Nevada. The blind science operation trials were designed to evaluate the extent to which FIDO-class rovers can be used to conduct traverse science and collect samples. FIDO-based instruments included stereo cameras for navigation and imaging, an infrared point spectrometer, a color microscopic imager for characterization of rocks and soils, and a rock drill for core acquisition. Body-mounted ``belly'' cameras aided drill deployment, and front and rear hazard cameras enabled terrain hazard avoidance. Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) data, a high spatial resolution IKONOS orbital image, and a suite of descent images were used to provide regional- and local-scale terrain and rock type information, from which hypotheses were developed for testing during operations. The rover visited three sites, traversed 30 m, and acquired 1.3 gigabytes of data. The relatively small traverse distance resulted from a geologically rich site in which materials identified on a regional scale from remote-sensing data could be identified on a local scale using rover-based data. Results demonstrate the synergy of mapping terrain from orbit and during descent using imaging and spectroscopy, followed by a rover mission to test inferences and to make discoveries that can be accomplished only with surface mobility systems.
Traverse velocity maps for human exploration
NASA Astrophysics Data System (ADS)
Heinicke, Christiane; Johnston, Carmel; Sefton-Nash, Elliot; Foing, Bernard
2017-04-01
It is often proposed that humans are more effective and efficient in conducting exploratory work during planetary missions than rovers. However, even humans are hindered by the restrictions of their suits and by necessary precautions to ensure the astronauts' safety. During the 12-month simulation at the Hawaii Space Exploration Analog and Simulation facility, several members of the six-person crew conducted a large number of exploratory expeditions under conditions similar to a Mars crew. Over the course of 145 extra-vehicular activities (EVAs), they traversed several thousand kilometers of various types of terrain. The actual walking speeds of the crew members have been correlated with different properties of the terrain as determined from field excursions and remote sensing. The resulting terrain and velocity maps can be used both for ground truthing of satellite imagery, and potential EVA planning on celestial bodies.
Lunar rover navigation concepts
NASA Astrophysics Data System (ADS)
Burke, James D.
1993-01-01
With regard to the navigation of mobile lunar vehicles on the surface, candidate techniques are reviewed and progress of simulations and experiments made up to now are described. Progress that can be made through precursor investigations on Earth is considered. In the early seventies the problem was examined in a series of relevant tests made in the California desert. Meanwhile, Apollo rovers made short exploratory sorties and robotic Lunokhods traveled over modest distances on the Moon. In these early missions some of the required methods were demonstrated. The navigation problem for a lunar traverse can be viewed in three parts: to determine the starting point with enough accuracy to enable the desired mission; to determine the event sequence required to reach the site of each traverse objective; and to redetermine actual positions enroute. The navigator's first tool is a map made from overhead imagery. The Moon was almost completely photographed at moderate resolution by spacecraft launched in the sixties, but that data set provides imprecise topographic and selenodetic information. Therefore, more advanced orbital missions are now proposed as part of a resumed lunar exploration program. With the mapping coverage expected from such orbiters, it will be possible to use a combination of visual landmark navigation and external radio and optical references (Earth and Sun) to achieve accurate surface navigation almost everywhere on the near side of the Moon. On the far side and in permanently dark polar areas, there are interesting exploration targets where additional techniques will have to be used.
Geologic Map of the Upper Parashant Canyon and Vicinity, Mohave County, Northwestern Arizona
Billingsley, George H.; Harr, Michelle L.; Wellmeyer, Jessica L.
2000-01-01
Introduction The geologic map of the upper Parashant Canyon area covers part of the Colorado Plateau and several large tributary canyons that make up the western part of Arizona's Grand Canyon. The map is part of a cooperative U.S. Geological Survey and National Park Service project to provide geologic information for areas within the newly established Grand Canyon/Parashant Canyon National Monument. Most of the Grand Canyon and parts of the adjacent plateaus have been geologically mapped; this map fills in one of the remaining areas where uniform quality geologic mapping was needed. The geologic information presented may be useful in future related studies as to land use management, range management, and flood control programs for federal and state agencies, and private concerns. The map area is in a remote region of the Arizona Strip, northwestern Arizona about 88 km south of the nearest settlement of St. George, Utah. Elevations range from about 1,097 m (3,600 ft) in Parashant Canyon (south edge of map area) to 2,145 m (7,037 ft) near the east-central edge of the map area. Primary vehicle access is by dirt road locally known as the Mount Trumbull road; unimproved dirt roads and jeep trails traverse various parts of the map area. Travel on the Mount Trumbull road is possible with 2-wheel-drive vehicles except during wet conditions. Extra fuel, two spare tires and extra food and water are highly recommended when traveling in this remote area. The map area includes about 26 sections of land belonging to the State of Arizona, about 40 sections of private land, and a small strip of the Lake Mead National Recreation Area (southeast edge of the map area). The private land is mainly clustered around the abandoned settlement of Mt. Trumbull, locally known as Bundyville, and a few sections are scattered in the upper Whitmore Canyon area just south of Bundyville. Lower elevations within the canyons support a sparse growth of sagebrush, cactus, grass, creosote bush, and a variety of desert shrubs. Sagebrush, grass, cactus, cliffrose bush, pinyon pine trees, juniper trees, and some ponderosa pines thrive at higher elevations. Surface runoff in the north half of the map area drains northward towards the Virgin River in Utah via Hurricane Wash. In the south half of the area, it drains towards the Colorado River in Grand Canyon via Parashant and Whitmore Canyons. Upper Parashant and Whitmore Canyons are part of the physiography of the western Grand Canyon, but are not included within Grand Canyon National Park. The entire map area is now within the newly established Grand Canyon/Parashant Canyon National Monument (as of January, 2000), and is jointly managed by the Lake Mead National Recreational Area, Boulder City, Nevada, and the Bureau of Land Management, Arizona Strip District, St. George, Utah. Surface runoff in the north half of the map area drains northward towards the Virgin River in Utah via Hurricane Wash. In the south half of the area, it drains towards the Colorado River in Grand Canyon via Parashant and Whitmore Canyons. Upper Parashant and Whitmore Canyons are part of the physiography of the western Grand Canyon, but are not included within Grand Canyon National Park. The entire map area is now within the newly established Grand Canyon/Parashant Canyon National Monument (January, 2000), and is jointly managed by the Lake Mead National Recreational Area, Boulder City, Nevada, and the Bureau of Land Management, Arizona Strip District, St. George, Utah.
Ramos, Rogelio; Zlatev, Roumen; Valdez, Benjamin; Stoytcheva, Margarita; Carrillo, Mónica; García, Juan-Francisco
2013-01-01
A virtual instrumentation (VI) system called VI localized corrosion image analyzer (LCIA) based on LabVIEW 2010 was developed allowing rapid automatic and subjective error-free determination of the pits number on large sized corroded specimens. The VI LCIA controls synchronously the digital microscope image taking and its analysis, finally resulting in a map file containing the coordinates of the detected probable pits containing zones on the investigated specimen. The pits area, traverse length, and density are also determined by the VI using binary large objects (blobs) analysis. The resulting map file can be used further by a scanning vibrating electrode technique (SVET) system for rapid (one pass) "true/false" SVET check of the probable zones only passing through the pit's centers avoiding thus the entire specimen scan. A complete SVET scan over the already proved "true" zones could determine the corrosion rate in any of the zones.
Simplified Parallel Domain Traversal
DOE Office of Scientific and Technical Information (OSTI.GOV)
Erickson III, David J
2011-01-01
Many data-intensive scientific analysis techniques require global domain traversal, which over the years has been a bottleneck for efficient parallelization across distributed-memory architectures. Inspired by MapReduce and other simplified parallel programming approaches, we have designed DStep, a flexible system that greatly simplifies efficient parallelization of domain traversal techniques at scale. In order to deliver both simplicity to users as well as scalability on HPC platforms, we introduce a novel two-tiered communication architecture for managing and exploiting asynchronous communication loads. We also integrate our design with advanced parallel I/O techniques that operate directly on native simulation output. We demonstrate DStep bymore » performing teleconnection analysis across ensemble runs of terascale atmospheric CO{sub 2} and climate data, and we show scalability results on up to 65,536 IBM BlueGene/P cores.« less
Spirit's Express Route to 'Columbia Hills'
NASA Technical Reports Server (NTRS)
2004-01-01
This map illustrates the Mars Exploration Rover Spirit's position as of sol 112 (April 26, 2004), near the crater called 'Missoula.' Like a train on a tight schedule, Spirit will make regular stops along the way to its ultimate destination, the 'Columbia Hills.' At each stop, or 'station,' the rover will briefly analyze the area's rocks and soils. Each tick mark on the rover's route represents one sol's worth of travel, or about 60 to 70 meters (200 to 230 feet). Rover planners estimate that Spirit will reach the hills around mid-June. Presently, the rover is stopped at a site called 'Plains Station.' The color thermal data show how well different surface features hold onto heat. Red indicates warmth; blue indicates coolness. Areas with higher temperatures are more likely to be rocky, as rocks absorb heat. Lower temperatures denote small particles and fewer rocks. During its traverse, Spirit will document the causes of these temperature variations. The map comprises data from the camera on NASA's Mars Global Surveyor orbiter and the thermal emission imaging system on NASA's Mars Odyssey orbiter.NASA Astrophysics Data System (ADS)
Hangai, Yoshihiko; Morita, Tomoaki; Koyama, Shinji; Kuwazuru, Osamu; Yoshikawa, Nobuhiro
2016-09-01
Functionally graded aluminum foam (FG Al foam) is a new class of Al foam in which the pore structure varies over the foam, resulting in corresponding variations in the mechanical properties of the foam. In this study, FG Al foam plates were fabricated by a friction powder sintering (FPS) process with a traversing tool that is based on a previously developed sintering and dissolution process. The variation of the mechanical properties was realized by setting the volume fraction φ of NaCl in the mixture to 60, 70, and 80%. Long FG Al foam plates were fabricated with a length equal to the tool traversing length with φ varying in the tool traversing direction. From x-ray computed tomography observation, it was shown that the density of the Al foam decreased with increasing φ. In contrast, almost uniform pore structures were obtained in each area. According to the results of compression tests on each area, the plateau stress and energy absorption tended to decrease with increasing φ. Therefore, it was shown that FG Al foam plates with varying mechanical properties can be fabricated by the FPS process with the traversing tool.
Geologic Mapping of Holden Crater and the Uzboi-Ladon-Morava Outflow System
NASA Technical Reports Server (NTRS)
Grant, J. A.; Irwin, R. P., III; Wilson, S. A.
2009-01-01
Geologic mapping in Margaritifer Terra (Fig. 1) yields important new information regarding the inventory, sources, and sinks of water during the Noachian and early Hesperian on Mars [1-7]. Drainage in southwest Margaritifer Terra is dominated by the segmented Uzboi-Ladon-Morava (ULM) meso-scale outflow system that traverses northward along the southwestern flank of the Chryse trough [4-9]. Mapping of lower Uzboi Vallis through Ladon basin highlights the extent and complexity of sedimentary deposits associated with the ULM system [5-13].
Analysis of ArcticDEM orthorectification for polar navigational traverses
NASA Astrophysics Data System (ADS)
Menio, E. C.; Deeb, E. J.; Weale, J.; Courville, Z.; Tracy, B.; Cloutier, M. D.; Cothren, J. D.; Liu, J.
2017-12-01
The availability and accessibility of high-resolution satellite imagery allows operational support teams to visually assess physical risks along traverse routes before and during the field season. In support of operations along the Greenland Inland Traverse (GrIT), DigitalGlobe's WorldView 0.5m resolution panchromatic imagery is analyzed to identify and digitize crevasse features along the route from Thule Air Force Base to Summit Station, Greenland. In the spring of 2016, field teams reported up to 150 meters of offset between the location of crevasse features on the ground and the location of the same feature on the imagery provided. Investigation into this issue identified the need to orthorectify imagery—use digital elevation models (DEMs) to correct viewing geometry distortions—to improve navigational accuracy in the field. It was previously thought that orthorectification was not necessary for applications in relatively flat terrain such as ice sheets. However, the surface elevations on the margins of the Greenland Ice Sheet vary enough to cause distortions in imagery, if taken obliquely. As is standard for requests, the Polar Geospatial Center (PGC) provides orthorectified imagery using the MEaSUREs Greenland Ice Mapping Project (GIMP) 30m digital elevation model. Current, higher-resolution elevation datasets, such as the ArcticDEM (2-5m resolution) and WorldView stereopair DEMs (2-3m resolution), are available for use in orthorectification. This study examines three heavily crevassed areas along the GrIT traverse, as identified in 2015 and 2016 imagery. We extracted elevation profiles along the GrIT route from each of the three DEMs: GIMP, ArcticDEM, and WorldView stereopair mosaic. Results show the courser GIMP data deviating significantly from the ArcticDEM and WorldView data, at points by up to 80m, which is seen as offset of features in plan view. In-situ Ground Penetrating Radar (GPR) surveys of crevasse crossings allow for evaluation of geopositional accuracy of each resulting orthorectified photo and a quantitative analysis of plan view offset.
Early LROC Views of Lunar 'Heritage' Sites
NASA Astrophysics Data System (ADS)
Stooke, P. J.
2010-03-01
Early LROC images show some old hardware locations including Apollo and Surveyor sites. The images are used to improve EVA traverse maps and to identify the discarded Surveyor 3 retro-rocket. Future opportunities to observe other items are discussed.
Detecting Traversable Area and Water Hazards for the Visually Impaired with a pRGB-D Sensor
Yang, Kailun; Wang, Kaiwei; Cheng, Ruiqi; Hu, Weijian; Huang, Xiao; Bai, Jian
2017-01-01
The use of RGB-Depth (RGB-D) sensors for assisting visually impaired people (VIP) has been widely reported as they offer portability, function-diversity and cost-effectiveness. However, polarization cues to assist traversability awareness without precautions against stepping into water areas are weak. In this paper, a polarized RGB-Depth (pRGB-D) framework is proposed to detect traversable area and water hazards simultaneously with polarization-color-depth-attitude information to enhance safety during navigation. The approach has been tested on a pRGB-D dataset, which is built for tuning parameters and evaluating the performance. Moreover, the approach has been integrated into a wearable prototype which generates a stereo sound feedback to guide visually impaired people (VIP) follow the prioritized direction to avoid obstacles and water hazards. Furthermore, a preliminary study with ten blindfolded participants suggests its effectivity and reliability. PMID:28817069
Mapping trace element distribution in fossil teeth and bone with LA-ICP-MS
NASA Astrophysics Data System (ADS)
Hinz, E. A.; Kohn, M. J.
2009-12-01
Trace element profiles were measured in fossil bones and teeth from the late Pleistocene (c. 25 ka) Merrell locality, Montana, USA, by using laser-ablation ICP-MS. Laser-ablation ICP-MS can collect element counts along predefined tracks on a sample’s surface using a constant ablation speed allowing for rapid spatial sampling of element distribution. Key elements analyzed included common divalent cations (e.g. Sr, Zn, Ba), a suite of REE (La, Ce, Nd, Sm, Eu, Yb), and U, in addition to Ca for composition normalization and standardization. In teeth, characteristic diffusion penetration distances for all trace elements are at least a factor of 4 greater in traverses parallel to the dentine-enamel interface (parallel to the growth axis of the tooth) than perpendicular to the interface. Multiple parallel traverses in sections parallel and perpendicular to the tooth growth axis were transformed into trace element maps, and illustrate greater uptake of all trace elements along the central axis of dentine compared to areas closer to enamel, or within the enamel itself. Traverses in bone extending from the external surface, through the thickness of cortical bone and several mm into trabecular bone show major differences in trace element uptake compared to teeth: U and Sr are homogeneous, whereas all REE show a kinked profile with high concentrations on outer surfaces that decrease by several orders of magnitude within a few mm inward. The Eu anomaly increases uniformly from the outer edge of bone inward, whereas the Ce anomaly decreases slightly. These observations point to major structural anisotropies in trace element transport and uptake during fossilization, yet transport and uptake of U and REE are not resolvably different. In contrast, transport and uptake of U in bone must proceed orders of magnitude faster than REE as U is homogeneous whereas REE exhibit strong gradients. The kinked REE profiles in bone unequivocally indicate differential transport rates, consistent with a double-medium diffusion model in which microdomains with slow diffusivities are bounded by fast-diffusing pathways.
Comparison of different methods for the assessment of the urban heat island in Stuttgart, Germany.
Ketterer, Christine; Matzarakis, Andreas
2015-09-01
This study of the urban heat island (UHI) aims to support planning authorities by going beyond the traditional way of urban heat island studies. Therefore, air temperature as well as the physiologically equivalent temperature (PET) were applied to take into account the effect of the thermal atmosphere on city dwellers. The analysis of the urban heat island phenomenon of Stuttgart, Germany, includes a long-term frequency analysis using data of four urban and one rural meteorological stations. A (high resolution map) of the UHI intensity and PET was created using stepwise multiple linear regression based on data of car traverses as well as spatial data. The mapped conditions were classified according to the long-term frequency analysis. Regarding climate change, the need for adaptation measures as urban greening is obvious. Therefore, a spatial analysis of quantification of two scenarios of a chosen study area was done by the application of a micro-scale model. The nocturnal UHI of Stuttgart is during 15 % stronger than 4 K in the city center during summer when daytime heat stress occurs during 40 %. A typical summer condition is mapped using statistical approach to point out the most strained areas in Stuttgart center and west. According to the model results, the increase in number of trees in a chosen area (Olga hospital) can decrease PET by 0.5 K at 22:00 CET but by maximum 27 K at 14:00 CET.
Geologic and Geophysical Framework of the Santa Rosa 7.5' Quadrangle, Sonoma County, California
McLaughlin, R.J.; Langenheim, V.E.; Sarna-Wojcicki, A. M.; Fleck, R.J.; McPhee, D.K.; Roberts, C.W.; McCabe, C.A.; Wan, Elmira
2008-01-01
The geologic and geophysical maps of Santa Rosa 7.5? quadrangle and accompanying structure sections portray the sedimentary and volcanic stratigraphy and crustal structure of the Santa Rosa 7.5? quadrangle and provide a context for interpreting the evolution of volcanism and active faulting in this region. The quadrangle is located in the California Coast Ranges north of San Francisco Bay and is traversed by the active Rodgers Creek, Healdsburg and Maacama Fault Zones. The geologic and geophysical data presented in this report, are substantial improvements over previous geologic and geophysical maps of the Santa Rosa area, allowing us to address important geologic issues. First, the geologic mapping is integrated with gravity and magnetic data, allowing us to depict the thicknesses of Cenozoic deposits, the depth and configuration of the Mesozoic basement surface, and the geometry of fault structures beneath this region to depths of several kilometers. This information has important implications for constraining the geometries of major active faults and for understanding and predicting the distribution and intensity of damage from ground shaking during earthquakes. Secondly, the geologic map and the accompanying description of the area describe in detail the distribution, geometry and complexity of faulting associated with the Rodgers Creek, Healdsburg and Bennett Valley Fault Zones and associated faults in the Santa Rosa quadrangle. The timing of fault movements is constrained by new 40Ar/39Ar ages and tephrochronologic correlations. These new data provide a better understanding of the stratigraphy of the extensive sedimentary and volcanic cover in the area and, in particular, clarify the formational affinities of Pliocene and Pleistocene nonmarine sedimentary units in the map area. Thirdly, the geophysics, particularly gravity data, indicate the locations of thick sections of sedimentary and volcanic fill within ground water basins of the Santa Rosa plain and Rincon, Bennett, and northwestern Sonoma Valleys, providing geohydrologists a more realistic framework for groundwater flow models.
NASA Technical Reports Server (NTRS)
Captain, J.; Elphic, R.; Colaprete, A.; Zacny, Kris; Paz, A.
2016-01-01
Data gathered from lunar missions within the last two decades have significantly enhanced our understanding of the volatile resources available on the lunar surface, specifically focusing on the polar regions. Several orbiting missions such as Clementine and Lunar Prospector have suggested the presence of volatile ices and enhanced hydrogen concentrations in the permanently shadowed regions of the moon. The Lunar Crater Observation and Sensing Satellite (LCROSS) mission was the first to provide direct measurement of water ice in a permanently shadowed region. These missions with other orbiting assets have laid the groundwork for the next step in the exploration of the lunar surface; providing ground truth data of the volatiles by mapping the distribution and processing lunar regolith for resource extraction. This next step is the robotic mission Resource Prospector (RP). Resource Prospector is a lunar mission to investigate 'strategic knowledge gaps' (SKGs) for in-situ resource utilization (ISRU). The mission is proposed to land in the lunar south pole near a permanently shadowed crater. The landing site will be determined by the science team with input from broader international community as being near traversable landscape that has a high potential of containing elevated concentrations of volatiles such as water while maximizing mission duration. A rover will host the Regolith & Environment Science and Oxygen & Lunar Volatile Extraction (RESOLVE) payload for resource mapping and processing. The science instruments on the payload include a 1-meter drill, neutron spectrometer, a near infrared spectrometer, an operations camera, and a reactor with a gas chromatograph-mass spectrometer for volatile analysis. After the RP lander safely delivers the rover to the lunar surface, the science team will guide the rover team on the first traverse plan. The neutron spectrometer (NS) and near infrared (NIR) spectrometer instruments will be used as prospecting tools to guide the traverse path. The NS will map the water-equivalent hydrogen concentration as low as 0.5% by weight to an 80 centimeter depth as the rover traverses the lunar landscape. The NIR spectrometer will measure surficial H2O/OH as well as general mineralogy. When the prospecting instruments identify a potential volatile-rich area during the course of a traverse, the prospect is then mapped out and the most promising location identified. An augering drill capable of sampling to a depth of 100 centimeters will excavate regolith for analysis. A quick assay of the drill cuttings will be made using an operations camera and NIR spectrometer. With the water depth confirmed by this first auguring activity, a regolith sample may be extracted for processing. The drill will deliver the regolith sample to a crucible that will be sealed and heated. Evolved volatiles will be measured by a gas chromatograph-mass spectrometer and the water will be captured and photographed. RP is a solar powered mission, which given the polar location translates to a relatively short mission duration on the order of 4-15 days. This short mission duration drives the concept of operations, instrumentation, and data analysis towards critical real time analysis and decision support. Previous payload field tests have increased the fidelity of the hardware, software, and mission operations. Current activities include a mission level field test to optimize interfaces between the payload and rover as well as better understand the interaction of the science and rover teams during the mission timeline. This paper will include the current status of the science instruments on the payload as well as the integrated field test occurring in fall of 2015. The concept of operations will be discussed, including the real time science and engineering decision-making process based on the critical data from the instrumentation. The path to flight will be discussed with the approach to this ambitious low cost mission.
Mapping the Apollo 17 Astronauts' Positions Based on LROC Data and Apollo Surface Photography
NASA Astrophysics Data System (ADS)
Haase, I.; Oberst, J.; Scholten, F.; Gläser, P.; Wählisch, M.; Robinson, M. S.
2011-10-01
The positions from where the Apollo 17 astronauts recorded panoramic image series, e.g. at the so-called "traverse stations", were precisely determined using ortho-images (0.5 m/pxl) as well as Digital Terrain Models (DTM) (1.5 m/pxl and 100 m/pxl) derived from Lunar Reconnaissance Orbiter Camera (LROC) data. Features imaged in the Apollo panoramas were identified in LROC ortho-images. Least-squares techniques were applied to angles measured in the panoramas to determine the astronaut's position to within the ortho-image pixel. The result of our investigation of Traverse Station 1 in the north-west of Steno Crater is presented.
NASA Technical Reports Server (NTRS)
Eppler, Dean B.; Bleacher, Jacob F.; Evans, Cynthia A.; Feng, Wanda; Gruener, John; Hurwitz, Debra M.; Skinner, J. A., Jr.; Whitson, Peggy; Janoiko, Barbara
2013-01-01
Geologic maps integrate the distributions, contacts, and compositions of rock and sediment bodies as a means to interpret local to regional formative histories. Applying terrestrial mapping techniques to other planets is challenging because data is collected primarily by orbiting instruments, with infrequent, spatiallylimited in situ human and robotic exploration. Although geologic maps developed using remote data sets and limited "Apollo-style" field access likely contain inaccuracies, the magnitude, type, and occurrence of these are only marginally understood. This project evaluates the interpretative and cartographic accuracy of both field- and remote-based mapping approaches by comparing two 1:24,000 scale geologic maps of the San Francisco Volcanic Field (SFVF), north-central Arizona. The first map is based on traditional field mapping techniques, while the second is based on remote data sets, augmented with limited field observations collected during NASA Desert Research & Technology Studies (RATS) 2010 exercises. The RATS mission used Apollo-style methods not only for pre-mission traverse planning but also to conduct geologic sampling as part of science operation tests. Cross-comparison demonstrates that the Apollo-style map identifies many of the same rock units and determines a similar broad history as the field-based map. However, field mapping techniques allow markedly improved discrimination of map units, particularly unconsolidated surficial deposits, and recognize a more complex eruptive history than was possible using Apollo-style data. Further, the distribution of unconsolidated surface units was more obvious in the remote sensing data to the field team after conducting the fieldwork. The study raises questions about the most effective approach to balancing mission costs with the rate of knowledge capture, suggesting that there is an inflection point in the "knowledge capture curve" beyond which additional resource investment yields progressively smaller gains in geologic knowledge.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1981-05-01
An airborne high sensitivity gamma-ray spectrometer and magnetometer survey was conducted over ten (10) areas over northern California and southwestern Oregon. These include the 2/sup 0/ x 1/sup 0/ NTMS quadrangles of Roseburg, Medford, Weed, Alturas, Redding, Susanville, Ukiah, and Chico along with the 1/sup 0/ x 2/sup 0/ areas of the Coos Bay quadrangle and the Crescent City/Eureka areas combined. This report discusses the results obtained over the Susanville, California, map area. Traverse lines were flown in an east-west direction at a line spacing of six (6) miles. Tie lines were flown north-south approximately eighteen (18) miles apart. Amore » total of 16,880.5 line miles of geophysical data were acquired, compiled, and interpreted during the survey, of which 1642.8 line miles are in this quadrangle. The purpose of this study is to acquire and compile geologic and other information with which to assess the magnitude and distribution of uranium resources and to determine areas favorable for the occurrence of uranium in the United States.« less
Airborne gamma-ray spectrometer and magnetometer survey, Medford Quadrangle Oregon. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1981-04-01
An airborne high sensitivity gamma-ray spectrometer and magnetometer survey was conducted over ten (10) areas over northern California and southwestern Oregon. These include the 2/sup 0/ x 1/sup 0/ NTMS quadrangles of Roseburg, Medford, Weed, Alturas, Redding, Susanville, Ukiah, and Chico along with the 1/sup 0/ x 2/sup 0/ areas of the Coos Bay quadrangle and the Crescent City/Eureka areas combined. This report discusses the results obtained over the Medford, Oregon, map area. Traverse lines were flown in an east-west direction at a line spacing of three miles. Tie lines were flown north-south approximately twelve miles apart. A total ofmore » 16,880.5 line miles of geophysical data were acquired, compiled, and interpreted during the survey, of which 2925 line miles are in this quadrangle. The purpose of this study is to acquire and compile geologic and other information with which to assess the magnitude and distribution of uranium resources and to determine areas favorable for the occurrence of uranium in the United States.« less
Ramos, Rogelio; Zlatev, Roumen; Valdez, Benjamin; Stoytcheva, Margarita; Carrillo, Mónica; García, Juan-Francisco
2013-01-01
A virtual instrumentation (VI) system called VI localized corrosion image analyzer (LCIA) based on LabVIEW 2010 was developed allowing rapid automatic and subjective error-free determination of the pits number on large sized corroded specimens. The VI LCIA controls synchronously the digital microscope image taking and its analysis, finally resulting in a map file containing the coordinates of the detected probable pits containing zones on the investigated specimen. The pits area, traverse length, and density are also determined by the VI using binary large objects (blobs) analysis. The resulting map file can be used further by a scanning vibrating electrode technique (SVET) system for rapid (one pass) “true/false” SVET check of the probable zones only passing through the pit's centers avoiding thus the entire specimen scan. A complete SVET scan over the already proved “true” zones could determine the corrosion rate in any of the zones. PMID:23691434
NASA Astrophysics Data System (ADS)
Galve, J. P.; Castañeda, C.; Gutiérrez, F.
2015-06-01
Previously not measured subsidence on railway tracks was detected using DInSAR displacement maps produced for the central sector of Ebro Valley (NE Spain). This area is affected by evaporite karst and the analyzed railway corridors traverse active sinkholes that produce deformations in these infrastructures. One of the railway tracks affected by slight settlements corresponds to the Madrid-Barcelona high-speed line, a transport infrastructure highly vulnerable to ground deformation processes. Our analysis based on DInSAR measurements and geomorphological surveys indicate that this line show dissolution-induced subsidence and compaction of anthropogenic deposits (infills and embankments). By using DInSAR techniques, it was also measured the significant subsidence related to the activity of sinkholes in the Castejón-Zaragoza conventional railway line. Thus, this study demonstrate that DInSAR velocity maps coupled with detailed geomorphological surveys may help in the identification of the sectors of railway tracks that may compromise the safety of travellers.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dékány, I.; Minniti, D.; Majaess, D.
2015-10-20
Solid insight into the physics of the inner Milky Way is key to understanding our Galaxy’s evolution, but extreme dust obscuration has historically hindered efforts to map the area along the Galactic mid-plane. New comprehensive near-infrared time-series photometry from the VVV Survey has revealed 35 classical Cepheids, tracing a previously unobserved component of the inner Galaxy, namely a ubiquitous inner thin disk of young stars along the Galactic mid-plane, traversing across the bulge. The discovered period (age) spread of these classical Cepheids implies a continuous supply of newly formed stars in the central region of the Galaxy over the lastmore » 100 million years.« less
NASA Astrophysics Data System (ADS)
Edgar, L. A.; Calef, F. J., III; Thomson, B. J.
2017-12-01
The Mars Science Laboratory (MSL) Curiosity rover is currently exploring the stratigraphy exposed in Aeolis Mons, the central mound of Gale crater. Gale crater has been the target of numerous remote sensing studies, aimed at understanding the origin and evolution of the mound, informally known as Mt. Sharp. A number of efforts have produced geologic maps of the mound and the MSL traverse path, in order to investigate the stratigraphic relationships between different sedimentary units. However, a scale gap exists between local mapping and stratigraphic analyses of the area explored by Curiosity and regional mapping of Aeolis Mons. As Curiosity explores the northwest flank of Aeolis Mons, there is a critical need for investigations to bridge this gap to enable rover-scale observations to be tied to orbital interpretations. This study is focused on detailed geologic mapping and stratigraphic correlations for the northwest flank of Aeolis Mons, including an area that the Curiosity rover will likely explore. The study region covers a 5.8 x 10 km area from approximately 137.27 to 137.44 °E and -4.70 to -4.82 °N. A 25 cm/pixel mosaic produced from images acquired by the High Resolution Imaging Science Experiment (HiRISE) camera provides a basemap for all mapping, and topographic information is provided by a HiRISE 1 m Digital Terrain Model. Preliminary digital geologic mapping was carried out at a scale of 1:10,000 to provide a framework for detailed geologic mapping efforts. Higher-resolution geologic mapping was then conducted at a scale of 1:2,000, and type localities were identified. As a result of newer, higher-resolution datasets that are now available and more narrowly focused mapping, we identify a number of new geologic units. Erosional remnants of some units point to a substantial erosional history. Collectively, the stratigraphy records diverse sedimentary environments and more variability in the depositional and erosional histories than previously identified. This study helps bridge the gap between previous mapping efforts and detailed rover-scale mapping, and will enable rover observations to be more closely tied to orbital interpretations across the northwest flank of Aeolis Mons.
Mobile robots traversability awareness based on terrain visual sensory data fusion
NASA Astrophysics Data System (ADS)
Shirkhodaie, Amir
2007-04-01
In this paper, we have presented methods that significantly improve the robot awareness of its terrain traversability conditions. The terrain traversability awareness is achieved by association of terrain image appearances from different poses and fusion of extracted information from multimodality imaging and range sensor data for localization and clustering environment landmarks. Initially, we describe methods for extraction of salient features of the terrain for the purpose of landmarks registration from two or more images taken from different via points along the trajectory path of the robot. The method of image registration is applied as a means of overlaying (two or more) of the same terrain scene at different viewpoints. The registration geometrically aligns salient landmarks of two images (the reference and sensed images). A Similarity matching techniques is proposed for matching the terrain salient landmarks. Secondly, we present three terrain classifier models based on rule-based, supervised neural network, and fuzzy logic for classification of terrain condition under uncertainty and mapping the robot's terrain perception to apt traversability measures. This paper addresses the technical challenges and navigational skill requirements of mobile robots for traversability path planning in natural terrain environments similar to Mars surface terrains. We have described different methods for detection of salient terrain features based on imaging texture analysis techniques. We have also presented three competing techniques for terrain traversability assessment of mobile robots navigating in unstructured natural terrain environments. These three techniques include: a rule-based terrain classifier, a neural network-based terrain classifier, and a fuzzy-logic terrain classifier. Each proposed terrain classifier divides a region of natural terrain into finite sub-terrain regions and classifies terrain condition exclusively within each sub-terrain region based on terrain spatial and textural cues.
Autonomous Rover Traverse and Precise Arm Placement on Remotely Designated Targets
NASA Technical Reports Server (NTRS)
Nesnas, Issa A.; Pivtoraiko, Mihail N.; Kelly, Alonzo; Fleder, Michael
2012-01-01
This software controls a rover platform to traverse rocky terrain autonomously, plan paths, and avoid obstacles using its stereo hazard and navigation cameras. It does so while continuously tracking a target of interest selected from 10 20 m away. The rover drives and tracks the target until it reaches the vicinity of the target. The rover then positions itself to approach the target, deploys its robotic arm, and places the end effector instrument on the designated target to within 2-3-cm accuracy of the originally selected target. This software features continuous navigation in a fairly rocky field in an outdoor environment and the ability to enable the rover to avoid large rocks and traverse over smaller ones. Using point-and-click mouse commands, a scientist designates targets in the initial imagery acquired from the rover s mast cameras. The navigation software uses stereo imaging, traversability analysis, path planning, trajectory generation, and trajectory execution. It also includes visual target tracking of a designated target selected from 10 m away while continuously navigating the rocky terrain. Improvements in this design include steering while driving, which uses continuous curvature paths. There are also several improvements to the traversability analyzer, including improved data fusion of traversability maps that result from pose estimation uncertainties, dealing with boundary effects to enable tighter maneuvers, and handling a wider range of obstacles. This work advances what has been previously developed and integrated on the Mars Exploration Rovers by using algorithms that are capable of traversing more rock-dense terrains, enabling tight, thread-the-needle maneuvers. These algorithms were integrated on the newly refurbished Athena Mars research rover, and were fielded in the JPL Mars Yard. Forty-three runs were conducted with targets at distances ranging from 5 to 15 m, and a success rate of 93% was achieved for placement of the instrument within 2-3 cm of the target.
The Scale of Exploration: Planetary Missions Set in the Context of Tourist Destinations on Earth
NASA Astrophysics Data System (ADS)
Garry, W. B.; Bleacher, L. V.; Bleacher, J. E.; Petro, N. E.; Mest, S. C.; Williams, S. H.
2012-03-01
What if the Apollo astronauts explored Washington, DC, or the Mars Exploration Rovers explored Disney World? We present educational versions of the traverse maps for Apollo and MER missions set in the context of popular tourist destinations on Earth.
Rock Statistics at the Mars Pathfinder Landing Site, Roughness and Roving on Mars
NASA Technical Reports Server (NTRS)
Haldemann, A. F. C.; Bridges, N. T.; Anderson, R. C.; Golombek, M. P.
1999-01-01
Several rock counts have been carried out at the Mars Pathfinder landing site producing consistent statistics of rock coverage and size-frequency distributions. These rock statistics provide a primary element of "ground truth" for anchoring remote sensing information used to pick the Pathfinder, and future, landing sites. The observed rock population statistics should also be consistent with the emplacement and alteration processes postulated to govern the landing site landscape. The rock population databases can however be used in ways that go beyond the calculation of cumulative number and cumulative area distributions versus rock diameter and height. Since the spatial parameters measured to characterize each rock are determined with stereo image pairs, the rock database serves as a subset of the full landing site digital terrain model (DTM). Insofar as a rock count can be carried out in a speedier, albeit coarser, manner than the full DTM analysis, rock counting offers several operational and scientific products in the near term. Quantitative rock mapping adds further information to the geomorphic study of the landing site, and can also be used for rover traverse planning. Statistical analysis of the surface roughness using the rock count proxy DTM is sufficiently accurate when compared to the full DTM to compare with radar remote sensing roughness measures, and with rover traverse profiles.
Jurmu, Michael C
2002-12-01
Twelve morphological features from research on alluvial streams are compared in four narrow, low-gradient wetland streams located in different geographic regions (Connecticut, Indiana, and Wisconsin, USA). All four reaches differed in morphological characteristics in five of the features compared (consistent bend width, bend cross-sectional shape, riffle width compared to pool width, greatest width directly downstream of riffles, and thalweg location), while three reaches differed in two comparisons (mean radius of curvature to width ratio and axial wavelength to width ratio). The remaining five features compared had at least one reach where different characteristics existed. This indicates the possibility of varying morphology for streams traversing wetland areas further supporting the concept that the unique qualities of wetland environments might also influence the controls on fluvial dynamics and the development of streams. If certain morphological features found in streams traversing wetland areas differ from current fluvial principles, then these varying features should be incorporated into future wetland stream design and creation projects. The results warrant further research on other streams traversing wetlands to determine if streams in these environments contain unique morphology and further investigation of the impact of low-energy fluvial processes on morphological development. Possible explanations for the morphology deviations in the study streams and some suggestions for stream design in wetland areas based upon the results and field observations are also presented.
An Automated Approach to Extracting River Bank Locations from Aerial Imagery Using Image Texture
2013-01-01
Atchafalaya River, LA. Map Data: Google, United States Department of Agriculture Farm Ser- vice Agency, Europa Technologies AUTOMATED RIVER BANK...traverse morphologically smooth landscapes including rivers in sand or ice . Within these limitations, we hold that this technique rep- resents a valuable
NASA Astrophysics Data System (ADS)
Brophy, E.; Hansen, E. C.; Möller, C.; Huffman, M.
2017-12-01
Mafic migmatites with amphibolitic melanosome and tonalitic leucosome are a common feature in continental collision orogenic zones. However, the anatexis of mafic rocks has received much less attention than anatexis in felsic, intermediate or pelitic compositions. We examined mafic migmatites along a traverse within the Eastern Segment of the 1.14-0.9 Ga Sveconorwegian orogen, between Forsheda and Fegen southern Sweden. This traverse occurs in the center of a >150 km metamorphic transition from sub-greenschist facies in the east to high-pressure granulite and eclogite facies in the west (Möller and Andersson, unpublished metamorphic map). The Eastern Segment is a parautochthonous belt made up of rocks of the Fennoscandian shield that were deformed and metamorphosed during the Sveconorwegian orogeny. Within the traverse amphibolite bodies occur within migmatitic felsic to intermediate orthogneisses. The first appearance of tonalitic leucosome in amphibolite was observed towards the eastern edge of the traverse and continued to occur sporadically westward ranging in abundance (by outcrop area) from 0 to 25 %. The mineral assemblage in amphibolite is hbl + plag ( An30) + qtz + bt ± grt ± ilm ± ttn ± py ± SO2-rich scp. No examples of peritectic pyroxene associated with leucosome were found. The lack of peritectic pyroxene suggests that a water-rich phase was present at the onset of anatexis. The highly variable amount of leucosome further suggests that the amount of melt generated was determined by the amount of water available. Together these suggest that partial was driven by the local influx of a water-rich fluid. In the higher grade portions further west migmatitic amphibolite with tonalitic leucosome occurs in two varieties: one with peritectic pyroxene and relatively small amounts of leucosome, interpreted as forming by water-undersaturated dehydration melting, and another without peritectic pyroxene and with larger amounts of leucosome which is interpreted as having formed from water-fluxed melting (Hansen et al., Lithos, 2015). Thus, water-undersaturated melting in mafic rocks appears to have been limited to the higher-grade portions of the orogen. The variable amounts of leucosome produced by partial melting indicate that the presence of water-rich fluids was localized rather than penetrative.
Geologic Map of the Clark Peak Quadrangle, Jackson and Larimer Counties, Colorado
Kellogg, Karl S.; Ruleman, Chester A.; Shroba, Ralph R.; Braddock, William A.
2008-01-01
The Clark Peak quadrangle encompasses the southern end of the Medicine Bow Mountains and the northernmost end of the Mummy Range. The Continental Divide traverses the map area and Highway 14 cross the Divide at Cameron Pass, in the southeastern corner of the map. Approximately the eastern half of the map, and a few areas to the west, are underlain by Early Proterozoic plutonic and metamorphic rocks. Most of these basement rocks are part of the ~1,715 Ma Rawah batholith, composed mostly of pinkish, massive to moderately foliated monzogranite and granodiorite intruded by numerous, large pegmatite- aplite bodies. The metamorphic rocks, many of which form large inclusions in the granitic rocks of the Rawah batholith, include biotite-hornblende gneiss, hornblende gneiss, amphibolite, and biotite schist. The crystalline basement rocks are thrust westward along the Medicine Bow thrust over a sequence of sedimentary rocks as old as the Upper Permian Satanka Shale. The Satanka Shale, Middle and Lower Triassic Chugwater group, and a thin sandstone tentatively correlated with the Lower Jurassic and Upper Triassic Jelm Formation are combined as one map unit. This undivided unit is overlain sequentially upward by the Upper Jurassic Sundance Formation, Upper Jurassic Morrison Formation, Lower Cretaceous Dakota Group, Upper and Lower Cretaceous Benton Group, Upper Cretaceous Niobrara Formation, and the Eocene and Paleocene Coalmont Formation. The Late Cretaceous to early Eocene Medicine Bow thrust is folded in places, and several back thrusts produced a complicated thrust pattern in the south part of the map. Early Oligocene magmatism produced rhyolite tuff, dacite and basalt flows, and intermediate dikes and small stocks. A 40Ar/39Ar date on sanidine from one rhyolite tuff is ~28.5 Ma; a similar whole-rock date on a trachybasalt is ~29.6 Ma. A very coarse, unsorted probably pre-Quaternary ridge-top diamicton crops out in the southern part of the quadrangle. Numerous glacial deposits (mostly of Pinedale age), rock glaciers, block-slope deposits, landslide deposits, talus deposits, fan deposits, colluvium, and alluvium comprise the surficial deposits of the map area.
Opportunity Traverse Map, Sol 383
NASA Technical Reports Server (NTRS)
2005-01-01
[figure removed for brevity, see original site] Figure 1 NASA's Mars Exploration Rover Opportunity drove a total of 2,801 meters (1.74 miles) between its landing in January 2004 and its 383rd martian day, or sol (Feb. 20, 2005). This map on an image taken by the Mars Orbiter Camera on NASA's Mars Global Surveyor shows the course the rover drove during that period. Recently, Opportunity has been making rapid progress from 'Endurance Crater' toward exploration targets farther south.Payne, Thomas G.
1982-01-01
REGIONAL MAPPER is a menu-driven system in the BASIC language for computing and plotting (1) time, depth, and average velocity to geologic horizons, (2) interval time, thickness, and interval velocity of stratigraphic intervals, and (3) subcropping and onlapping intervals at unconformities. The system consists of three programs: FILER, TRAVERSER, and PLOTTER. A control point is a shot point with velocity analysis or a shot point at or near a well with velocity check-shot survey. Reflection time to and code number of seismic horizons are filed by digitizing tablet from record sections. TRAVERSER starts at a point of geologic control and, in traversing to another, parallels seismic events, records loss of horizons by onlap and truncation, and stores reflection time for geologic horizons at traversed shot points. TRAVERSER is basically a phantoming procedure. Permafrost thickness and velocity variations, buried canyons with low-velocity fill, and error in seismically derived velocity cause velocity anomalies that complicate depth mapping. Two depths to the top of the pebble is based shale are computed for each control point. One depth, designated Zs on seismically derived velocity. The other (Zw) is based on interval velocity interpolated linearly between wells and multiplied by interval time (isochron) to give interval thickness. Z w is computed for all geologic horizons by downward summation of interval thickness. Unknown true depth (Z) to the pebble shale may be expressed as Z = Zs + es and Z = Zw + ew where the e terms represent error. Equating the two expressions gives the depth difference D = Zs + Zw = ew + es A plot of D for the top of the pebble shale is readily contourable but smoothing is required to produce a reasonably simple surface. Seismically derived velocity used in computing Zs includes the effect of velocity anomalies but is subject to some large randomly distributed errors resulting in depth errors (es). Well-derived velocity used in computing Zw does not include the effect of velocity anomalies, but the error (ew) should reflect these anomalies and should be contourable (non-random). The D surface as contoured with smoothing is assumed to represent ew, that is, the depth effect of variations in permafrost thickness and velocity and buried canyon depth. Estimated depth (Zest) to each geologic horizon is the sum of Z w for that horizon and a constant e w as contoured for the pebble shale, which is the first highly continuous seismic horizon below the zone of anomalous velocity. Results of this 'depthing' procedure are compared with those of Tetra Tech, Inc., the subcontractor responsible for geologic and geophysical interpretation and mapping.
Geologic Map of Part of the Uinkaret Volcanic Field, Mohave County, Northwestern Arizona
Billingsley, George H.; Hamblin, W. Kenneth; Wellmeyer, Jessica L.; Dudash, Stephanie L.
2001-01-01
The geologic map of part of the Uinkaret Volcanic Field is one product of a cooperative project between the U.S. Geological Survey, the National Park Service, and the Bureau of Land Management to provide geologic information about this part of the Grand Canyon-Parashant Canyon National Monument of Arizona. The Uinkaret Volcanic Field is a unique part of western Grand Canyon where volcanic rocks have preserved the geomorphic development of the landscape. Most of the Grand Canyon, and parts of adjacent plateaus have already been mapped. This map completes one of the remaining areas where uniform quality geologic mapping was needed. A few dozen volcanoes and lava flows within the Grand Canyon are not included in the map area, but their geologic significance to Grand Canyon development is documented by Hamblin (1994) and mapped by Billingsley and Huntoon (1983) and Wenrich and others (1997). The geologic information in this report may be useful to resource managers of the Bureau of Land Management for range management, biological, archaeological, and flood control programs. The map area lies within the Shivwits, Uinkaret, and Kanab Plateaus, which are subplateaus of the Colorado Plateaus physiographic province (Billingsley and others, 1997), and is part of the Arizona Strip north of the Colorado River. The nearest settlement is Colorado City, Arizona, about 58 km (36 mi) north of the map area (fig. 1). Elevations range from about 2,447 m (8,029 ft) at Mount Trumbull, in the northwest quarter of the map area, to about 732 m (2,400 ft) in Cove Canyon, in the southeast quarter of the map area. Vehicle access is via the Toroweap and Mount Trumbull dirt roads (fig. 1). Unimproved dirt roads traverse other parts of the area except in designated wilderness. Extra fuel, two spare tires, and extra food and water are highly recommended for travelers in this remote area. The U.S. Bureau of Land Management, Arizona Strip Field Office, St. George, Utah manages most of the area. In addition, there are 12 sections belonging to the State of Arizona, about 12 sections are private land, and several sections are within the Grand Canyon National Park and Lake Mead National Recreational Area (U.S. Department of the Interior, 1993). The private land is in Potato Valley and Lake Valley, southwest and west of Mount Trumbull, and in Whitmore Canyon and Toroweap (Tuweap) Valley. Portions of the Sawmill Mountains, Mount Logan, and Mount Trumbull areas were originally established as part of the Dixie National Forest in 1904. In 1924, Dixie National Forest land became part of the Kaibab National Forest. Then on February 13, 1974, management of this part of the Kaibab National Forest was transferred to the Bureau of Land Management, Arizona Strip Field Office (personal commun. Becky Hammond, Bureau of Land Management, 1997). Mount Logan and part of the Sawmill Mountains are now designated as the Mount Logan Wilderness Area, and Mount Trumbull is designated as the Mount Trumbull Wilderness Area. Most of the map area is now part of the new Grand Canyon-Parashant Canyon National Monument established January 11, 2000. Lower elevations within Hells Hollow, Whitmore Canyon, Toroweap Valley, and Cove Canyon support a sparse growth of sagebrush, cactus, grass, and a variety of desert shrubs. Sagebrush, grass, cactus, cliffrose bush, pinion pine, and juniper trees thrive at elevations above 1,830 m (6,000 ft). Ponderosa pine and oak forests thrive at higher elevations in the Mount Trumbull and Mount Logan areas. Surface runoff within the map area drains south towards the Colorado River through Hells Hole, Hollow, Whitmore Canyon, Toroweap Valley, and Cove Canyon. Upper Toroweap Valley, upper Hells Hollow, and Whitmore Canyon are part of the physiographic area of Grand Canyon, but are not within Grand Canyon National Park (Billingsley and others, 1997). As of January 11, 2000, these areas are now part of the new Grand Canyon-Parashant
USDA-ARS?s Scientific Manuscript database
Infection of the host with Mycobacterium avium subsp. paratuberculosis (MAP) results in a chronic and progressive enteritis that traverses both subclinical and clinical stages. The mechanism(s) for the shift from asymptomatic subclinical disease state to advanced clinical disease are not fully under...
APOLLO 16 ASTRONAUTS UNDERGO SIMULATED LUNAR TRAVERSE DURING TRAINING
NASA Technical Reports Server (NTRS)
1972-01-01
The Apollo 16 flight crew, astronauts Charles M. Duke, Jr., and John W. Young, prepare to undergo a simulated lunar traverse in the training area. The National Aeronautics and Space Administration Apollo 16, the eighth Apollo Lunar landing, is scheduled to land in the mountainous highland region near the crater Descartes to explore the area for a three day period collecting surface material. Making geological observations, and deploying the fourth geophysical station on the Moon. The flight crew of the mission are: John W. Young, commander; Charles M. Duke, Jr., lunar module pilot; and Thomas K. Mattingly II, command module pilot.
The Remote Sensing of Surface Radiative Temperature over Barbados.
remote sensing of surface radiative temperature over Barbados was undertaken using a PRT-5 attached to a light aircraft. Traverses across the centre of the island, over the rugged east coast area, and the urban area of Bridgetown were undertaken at different times of day and night in the last week of June and the first week of December, 1969. These traverses show that surface variations in long-wave radiation emission lie within plus or minus 5% of the observations over grass at a representative site. The quick response of the surface to sunset and sunrise was
Airborne gamma-ray spectrometer and magnetometer survey: Chico quadrangle, California. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1981-05-01
An airborne high sensitivity gamma-ray spectrometer and magnetometer survey was conducted over ten (10) areas over northern California and southwestern Oregon. These include the 2/sup 0/ x 1/sup 0/ NTMS quadrangles of Roseburg, Medford, Weed, Alturas, Redding, Susanville, Ukiah, and Chico along with the 1/sup 0/ x 2/sup 0/ areas of the Coos Bay quadrangle and the Crescent City/Eureka areas combined. This report discusses the results obtained over the Chico, California, map area. Traverse lines were flown in an east-west direction at a line spacing of three. Tie lines were flown north-south approximately twelve miles apart. A total of 16,880.5more » line miles of geophysical data were acquired, compiled, and interpreted during the survey, of which 3026.4 line miles are in the quadrangle. The purpose of this study is to acquire and compile geologic and other information with which to assess the magnitude and distribution of uranium resources with which to assess the magnitude and distribution of uranium resources and to determine areas favorable for the occurrence of uranium in the United States.« less
Ohlin, Henry N.; McLaughlin, Robert J.; Moring, Barry C.; Sawyer, Thomas L.
2010-01-01
The Lake Pillsbury area lies in the eastern part of the northern California Coast Ranges, along the east side of the transform boundary between the Pacific and North American plates (fig. 1). The Bartlett Springs Fault Zone is a northwest-trending zone of faulting associated with this eastern part of the transform boundary. It is presently active, based on surface creep (Svarc and others, 2008), geomorphic expression, offset of Holocene units (Lienkaemper and Brown, 2009), and microseismicity (Bolt and Oakeshott, 1982; Dehlinger and Bolt, 1984; DePolo and Ohlin, 1984). Faults associated with the Bartlett Springs Fault Zone at Lake Pillsbury are steeply dipping and offset older low to steeply dipping faults separating folded and imbricated Mesozoic terranes of the Franciscan Complex and interleaved rocks of the Coast Range Ophiolite and Great Valley Sequence. Parts of this area were mapped in the late 1970s and 1980s by several investigators who were focused on structural relations in the Franciscan Complex (Lehman, 1978; Jordan, 1975; Layman, 1977; Etter, 1979). In the 1980s the U.S. Geological Survey (USGS) mapped a large part of the area as part of a mineral resource appraisal of two U.S. Forest Service Roadless areas. For evaluating mineral resource potential, the USGS mapping was published at a scale of 1:62,500 as a generalized geologic summary map without a topographic base (Ohlin and others, 1983; Ohlin and Spear, 1984). The previously unpublished mapping with topographic base is presented here at a scale of 1:30,000, compiled with other mapping in the vicinity of Lake Pillsbury. The mapping provides a geologic framework for ongoing investigations to evaluate potential earthquake hazards and structure of the Bartlett Springs Fault Zone. This geologic map includes part of Mendocino National Forest (the Elk Creek Roadless Area) in Mendocino, Glenn, and Lake Counties and is traversed by several U.S. Forest Service Routes, including M1 and M6 (fig. 2). The study area is characterized by northwest-trending ridges separated by steep-sided valleys. Elevations in this part of the Coast Ranges vary from 1,500 ft (457 m) to 6,600 ft (2,012 m), commonly with gradients of 1,000 ft per mile (90 m per km). The steep slopes are covered by brush, grass, oak, and conifer forests. Access to most of the area is by county roads and Forest Service Route M6 from Potter Valley to Lake Pillsbury and by county road and Forest Service Route M6 and M1 from Upper Lake and State Highway 20. From the north, State Highway 261 provides access from Covelo. Forest Service Route M1 trends roughly north from its intersection with Route M6 south of Hull Mountain and through the Elk Creek and Black Butte Roadless areas to State Highway 261. Side roads used for logging and jeep trails provide additional access in parts of the area.
Interpretation of Local Gravity Anomalies in Northern New York
NASA Astrophysics Data System (ADS)
Revetta, F. A.
2004-05-01
About 10,000 new gravity measurements at a station spacing of 1 to 2 Km were made in the Adirondack Mountains, Lake Champlain Valley, St. Lawrence River Valley and Tug Hill Plateau. These closely spaced gravity measurements were compiled to construct computer contoured gravity maps of the survey areas. The gravity measurements reveal local anomalies related to seismicity, faults, mineral resources and gas fields that are not seen in the regional gravity mapping. In northern New York gravity and seismicity maps indicate epicenters are concentrated in areas of the most pronounced gravity anomalies along steep gravity gradients. Zones of weakness along the contacts of these lithologies of different density could possibly account for the earthquakes in this high stress area. Also, a computer contoured gravity map of the 5.3 magnitude Au Sable Forks earthquake of April 20, 2002 indicates the epicenter lies along a north-south trending gravity gradient produced by a high angle fault structure separating a gravity low in the west from high gravity in the east. In the St. Lawrence Valley, the Carthage-Colton Mylonite Zone, a major northeast trending structural boundary between the Adirondack Highlands and Northwest Lowlands, is represented as a steep gravity gradient extending into the eastern shore of Lake Ontario. At Russell, New York near the CCMZ, a small circular shaped gravity high coincides with a cluster of earthquakes. The coincidence of the epicenters over the high may indicate stress amplification at the boundary of a gabbro pluton. The Morristown fault located in the Morristown Quadrangle in St. Lawrence County produces both gravity and magnetic anomalies due to Precambrian Basement faulting. This faulting indicates control of the Morristown fault in the overlying Paleozoics by the Precambrian faults. Gravity and magnetic anomalies also occur over proposed extensions of the Gloucester and Winchester Springs faults into northern New York. Gravity and magnetic surveys were conducted at the closed Benson Mines magnetite mine and the Zinc Mines at Balmat, New York. The gravity and magnetic anomalies at Benson Mines indicate that significant amounts of magnetite remain in the subsurface and the steep gradients indicate a shallow depth. A gravity high of 35 gravity units in the Sylvia Lake Zinc District at Balmat, New York occurs over the upper marble and a 100 gu anomaly occurs just northeast of the zinc district. Abandoned natural gas fields exist along the southern and southwestern boundary of the Tug Hill Plateau. Gravity surveys were conducted in the vicinity of three of these gas fields in the Tug Hill Plateau (Camden, Sandy Creek and Pulaski). The Tug Hill Plateau is thought to be an uplifted-fault-bounded block which, if correct, might account for the existence of those gas fields. The trends of the gravity contours on the gravity maps lends credence to the fault interpretation. Also gravity and magnetic traverses were conducted across faults in the Trenton-Black River. These traverses show gravity anomalies across the faults which indicate control by faulting in the Precambrian.
NASA Astrophysics Data System (ADS)
Pondthai, P.; Udphuay, S.
2013-05-01
The magnitude of 5.1 Mw earthquake occurred in San Sai District, Chiang Mai Province, Thailand in December 2006 was considered an uncommon event due to the fact that there was no statistical record of such significant earthquake in the area. Therefore the earthquake might have been associated with a potentially active fault zone within the area. The objective of this study is to measure soil gas radon across this unknown fault zone within the Chiang Mai Basin, northern Thailand. Two profiles traversing the expected fault zone of soil gas radon measurements have been monitored, using TASTRAK solid state track nuclear detectors (SSNTDs). Radon signals from three periods of measurement show a distinctive consistent spatial distribution pattern. Anomalous radon areas along the profiles are connected to fault locations previously interpreted from other geophysical survey results. The increased radon signal changes from the radon background level with the signal-to-background ratio above 3 are considered anomalous. Such pattern of radon anomaly supports the existence of the faults. The radon measurement, therefore is a powerful technique in mapping active fault zone.
Spirit's Express Route to 'Columbia Hills'
NASA Technical Reports Server (NTRS)
2004-01-01
This map illustrates the Mars Exploration Rover Spirit's position as of sol 112 (April 26, 2004), near the crater called 'Missoula.' Like a train on a tight schedule, Spirit will make regular stops along the way to its ultimate destination, the 'Columbia Hills.' At each stop, or 'station,' the rover will briefly analyze the area's rocks and soils. Each tick mark on the rover's route represents one sol's worth of travel, or about 60 to 70 meters (200 to 230 feet). Rover planners estimate that Spirit will reach the hills around mid-June. Presently, the rover is stopped at a site called 'Plains Station.' The color thermal data show how well different surface features hold onto heat. Red indicates a higher thermal inertia associated with rocky terrain (cooler in the day, warmer at night); blue indicates a lower thermal inertia associated with smaller particles and fewer rocks (warmer at night, cooler in the day). During its traverse, Spirit will document the causes of these thermal variations. The map comprises data from the camera on NASA's Mars Global Surveyor orbiter and the thermal emission imaging system on NASA's Mars Odyssey orbiter.Theta phase precession of grid and place cell firing in open environments
Jeewajee, A.; Barry, C.; Douchamps, V.; Manson, D.; Lever, C.; Burgess, N.
2014-01-01
Place and grid cells in the rodent hippocampal formation tend to fire spikes at successively earlier phases relative to the local field potential theta rhythm as the animal runs through the cell's firing field on a linear track. However, this ‘phase precession’ effect is less well characterized during foraging in two-dimensional open field environments. Here, we mapped runs through the firing fields onto a unit circle to pool data from multiple runs. We asked which of seven behavioural and physiological variables show the best circular–linear correlation with the theta phase of spikes from place cells in hippocampal area CA1 and from grid cells from superficial layers of medial entorhinal cortex. The best correlate was the distance to the firing field peak projected onto the animal's current running direction. This was significantly stronger than other correlates, such as instantaneous firing rate and time-in-field, but similar in strength to correlates with other measures of distance travelled through the firing field. Phase precession was stronger in place cells than grid cells overall, and robust phase precession was seen in traversals through firing field peripheries (although somewhat less than in traversals through the centre), consistent with phase coding of displacement along the current direction. This type of phase coding, of place field distance ahead of or behind the animal, may be useful for allowing calculation of goal directions during navigation. PMID:24366140
Pelletier, David; Clark, Melissa; Anderson, Mark G; Rayfield, Bronwyn; Wulder, Michael A; Cardille, Jeffrey A
2014-01-01
Connectivity models are useful tools that improve the ability of researchers and managers to plan land use for conservation and preservation. Most connectivity models function in a point-to-point or patch-to-patch fashion, limiting their use for assessing connectivity over very large areas. In large or highly fragmented systems, there may be so many habitat patches of interest that assessing connectivity among all possible combinations is prohibitive. To overcome these conceptual and practical limitations, we hypothesized that minor adaptation of the Circuitscape model can allow the creation of omnidirectional connectivity maps illustrating flow paths and variations in the ease of travel across a large study area. We tested this hypothesis in a 24,300 km(2) study area centered on the Montérégie region near Montréal, Québec. We executed the circuit model in overlapping tiles covering the study region. Current was passed across the surface of each tile in orthogonal directions, and then the tiles were reassembled to create directional and omnidirectional maps of connectivity. The resulting mosaics provide a continuous view of connectivity in the entire study area at the full original resolution. We quantified differences between mosaics created using different tile and buffer sizes and developed a measure of the prominence of seams in mosaics formed with this approach. The mosaics clearly show variations in current flow driven by subtle aspects of landscape composition and configuration. Shown prominently in mosaics are pinch points, narrow corridors where organisms appear to be required to traverse when moving through the landscape. Using modest computational resources, these continuous, fine-scale maps of nearly unlimited size allow the identification of movement paths and barriers that affect connectivity. This effort develops a powerful new application of circuit models by pinpointing areas of importance for conservation, broadening the potential for addressing intriguing questions about resource use, animal distribution, and movement.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dill, R.F.; Slosson, J.E.; McEachen, D.B.
1990-05-01
A Macintosh II{sup TM} computer and commercially available software were used to analyze and depict the topography, construct an isopach sediment thickness map, plot core positions, and locate the geology of an offshore area facing an active landslide on the southern side of Palos Verdes Peninsula California. Profile data from side scan sonar, 3.5 kHz, and Boomer subbottom, high-resolution seismic, diving, echo sounder traverses, and cores - all controlled with a mini Ranger II navigation system - were placed in MacGridzo{sup TM} and WingZ{sup TM} software programs. The computer-plotted data from seven sources were used to construct maps with overlaysmore » for evaluating the possibility of a shoreside landslide extending offshore. The poster session describes the offshore survey system and demonstrates the development of the computer data base, its placement into the MacGridzo{sup TM} gridding program, and transfer of gridded navigational locations to the WingZ{sup TM} data base and graphics program. Data will be manipulated to show how sea-floor features are enhanced and how isopach data were used to interpret the possibility of landslide displacement and Holocene sea level rise. The software permits rapid assessment of data using computerized overlays and a simple, inexpensive means of constructing and evaluating information in map form and the preparation of final written reports. This system could be useful in many other areas where seismic profiles, precision navigational locations, soundings, diver observations, and core provide a great volume of information that must be compared on regional plots to develop of field maps for geological evaluation and reports.« less
On the Moon with Apollo 16. A Guidebook to the Descartes Region.
ERIC Educational Resources Information Center
Simmons, Gene
The Apollo 16 guidebook describes and illustrates (with artist concepts) the physical appearance of the lunar region visited. Maps show the planned traverses (trips on the lunar surface via Lunar Rover); the plans for scientific experiments are described in depth; and timelines for all activities are included. A section on "The Crew" is…
ERIC Educational Resources Information Center
Confrey, Jere; Gianopulos, Garron; McGowan, William; Shah, Meetal; Belcher, Michael
2017-01-01
The paper describes how designers used the construct of learning trajectories to create a tool, Math-Mapper 6-8, to help scaffold curricula toward increased learner-centered coherence. It defines "learner-centered curricular coherence" as "an organizational means to promote a high likelihood that each learner traverses one of many…
,
1979-01-01
Available are four multichannel profiles collected by Digicon Geophysical Corporation in 1975 using a 48-channel streamer (3600 m long), and a 27.9 cubic liter airgun array. They were processed in Denver on the Phoenix "I" by William C. Petterson. The processing includes demultiplexing and resampling, geometry and common-depth-point, definition, velocity analysis noise muting, band-pass filtering, time-variant filtering, time-variant deconvolution, and automatic gain control (AGC) sealing, prior to the final profile playout.The release includes pares of or all of four lines off the eastern United States (see map) over the Georges Bank basin and the Long Island platform and upper continental rise. These profiles were collected as a part of a regional arid over the offshore Atlantic sedimentary basins as a part of a continuing program to assess the resource potential using non-proprietary data. Lines 7 and 8 are cross-shelf profiles (280 ken and 400 km long respectively) taken across Georges Basin George Bank, the continental slope and rise east of Massachusetts. A five kilometer gap exists in line 8C near the outer edge of the shelf because the high concentration of lobster pots there prevented a continous traverse through the area. Line 12 (shotpoint 5988 - 14380, parts E, F, G, H, I and J) is along-the-shelf profile, and stretches from the vicinity of Husdon Channel (mid-shelf east of New Jersey) to Browns Bank, 100 km southeast of Nova Scotia, terminating in the vicinity of the Shell Mohawk (B-93) hole. Line 13 (shotpoint 83-11295, 1120 km) traverse the upper Continental rise between Cape Hatteras and Georges Bank.These profiles including velocity scans and shot point maps, may be viewed at U. S. Geological Survey Office, Bldg. B, Quissett Campus, Woods Hole, MA., and U. S. Geological Survey Office, Bldg. 25 at the Denver Federal Center. Copies of maps, scans and profiles can be purchased from the National Geophysical Solar-Terrestrial Data center, Environmental Data Service - NOAA, Code D 621, Boulder, Co. 80303.
View of rim of South Ray crater on traverse up Stone Mountain during EVA
NASA Technical Reports Server (NTRS)
1972-01-01
A view of the rim of South Ray crater photographed with a 500mm lens from Station no.4 -- the highest point on the traverse up Stone Mountain -- during the second Apollo 16 extravehicular activity (EVA-2) at the Descartes landing site. South Ray crater was a 'fresh' source of angular ejecta in the Lunar Module-Apollo Lunar Surface Experiments Package area and for samples at Station No.8.
NASA Technical Reports Server (NTRS)
Cucinotta, F. A.; Nikjoo, H.; Goodhead, D. T.; Wilson, J. W. (Principal Investigator)
1998-01-01
It is a common practice to estimate the number of particle-track traversals per cell or cell nucleus as the product of the ion's linear energy transfer (LET) and cell area. This practice ignores the effects of track width due to the lateral extension of delta rays. We make estimates of the number of particle-track traversals per cell, which includes the effects of delta rays using radial cutoffs in the ionization density about an ion's track of 1 mGy and 1 cGy. Calculations for laboratory and space radiation exposures are discussed, and show that the LET approximation provides a large underestimate of the actual number of particle-track traversals per cell from high-charge and energy (HZE) ions. In light of the current interest in the mechanisms of radiation action, including signal transduction and cytoplasmic damage, these results should be of interest for radiobiology studies with HZE ions.
Bathymetry & Geomorphology - A New Seafloor Mapping of the Israeli Exclusive Economic Zone
NASA Astrophysics Data System (ADS)
Tibor, G.; Hall, J. K.; Kanari, M.; Sade, R. A.; Sade, H.; Amit, G.; Gur-Arie, L.; Ketter, T.
2017-12-01
Recent extensive activities of oil and gas exploration and production companies in the Israeli Exclusive Economic Zone (EEZ) raised the need for an up-to-date baseline mapping of the seafloor to assist policy makers. The baseline mapping focused on bathymetry, geomorphology, geology, biodiversity, infauna and habitat in order to compile a sensitivity map for the Petroleum Commissioner in the Ministry of Energy in the bid for opening the sea to new natural gas and oil explorations. The Israeli EEZ covers an area of 25,950 sq. km. and reaches a maximum water depth of 2,100 m. It is located within the Levantine Basin, a zone of compression and strike-slip tectonics as Africa pushes into Eurasia. These forces operate on a half kilometer thick of Messinian evaporates and over a dozen kilometers of Pliocene and Pleistocene sediments to produce a complex seafloor morphology. The margin is cut by numerous slumps and canyons, while the basin is traversed by deep sea channels emptying into the moat around Eratosthenes Seamount farther north. The bathymetric and geomorphological mapping was done in three phases using Kongsberg and Elac multibeam sonars installed on different research vessels. The last phase (Aug.-Sept., 2016) covering depths from 1,400 to 2,100 m used the Kongsberg EM302 sonar installed on our new governmental research vessel Bat Galim. It has "state of the art" capabilities to map, sample and analyze the water column, seafloor and sub-bottom from water depths of 10m to 7,000 m. These mapping capabilities are unique in our region, the Eastern Mediterranean and the Red Sea, so we hope to promote research collaborations with our neighbors.
Potential mapping with charged-particle beams
NASA Technical Reports Server (NTRS)
Robinson, J. W.; Tillery, D. G.
1979-01-01
Experimental methods of mapping the equipotential surfaces near some structure of interest rely on the detection of charged particles which have traversed the regions of interest and are detected remotely. One method is the measurement of ion energies for ions created at a point of interest and expelled from the region by the fields. The ion energy at the detector in eV corresponds to the potential where the ion was created. An ionizing beam forms the ions from background neutrals. The other method is to inject charged particles into the region of interest and to locate their exit points. A set of several trajectories becomes a data base for a systematic mapping technique. An iterative solution of a boundary value problem establishes concepts and limitations pertaining to the mapping problem.
Geologic map of the St. Joe quadrangle, Searcy and Marion Counties, Arkansas
Hudson, Mark R.; Turner, Kenzie J.
2009-01-01
This map summarizes the geology of the St. Joe 7.5-minute quadrangle in the Ozark Plateaus region of northern Arkansas. Geologically, the area lies on the southern flank of the Ozark dome, an uplift that exposes oldest rocks at its center in Missouri. Physiographically, the St. Joe quadrangle lies within the Springfield Plateau, a topographic surface generally held up by Mississippian cherty limestone. The quadrangle also contains isolated mountains (for example, Pilot Mountain) capped by Pennsylvanian rocks that are erosional outliers of the higher Boston Mountains plateau to the south. Tomahawk Creek, a tributary of the Buffalo River, flows through the eastern part of the map area, enhancing bedrock erosion. Exposed bedrock of this region comprises an approximately 1,300-ft-thick sequence of Ordovician, Mississippian, and Pennsylvanian carbonate and clastic sedimentary rocks that have been mildly deformed by a series of faults and folds. The geology of the St. Joe quadrangle was mapped by McKnight (1935) as part of a larger area at 1:125,000 scale. The current map confirms many features of this previous study, but it also identifies new structures and uses a revised stratigraphy. Mapping for this study was conducted by field inspection of numerous sites and was compiled as a 1:24,000-scale geographic information system (GIS) database. Locations and elevations of sites were determined with the aid of a global positioning satellite receiver and a hand-held barometric altimeter that was frequently recalibrated at points of known elevation. Hill-shade-relief and slope maps derived from a U.S. Geological Survey 10-m digital elevation model as well as U.S. Geological Survey orthophotographs from 2000 were used to help trace ledge-forming units between field traverses within the Upper Mississippian and Pennsylvanian part of the stratigraphic sequence. Strikes and dips of beds were typically measured along stream drainages or at well-exposed ledges. Beds dipping less than 2 degrees are shown as horizontal. Structure contours constructed on the base of the Boone Formation were hand drawn based on elevations of control points on both lower and upper contacts of the Boone Formation as well as other limiting information on their maximum or minimum elevations.
Space charge tune shift, fast resonance traversal, and current limits in circular accelerators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rees, G.H.
1996-06-01
Space charge tune shifts, fast resonance traversals, and current limits are important design issues for low energy, high power circular accelerators. Areas of interest are accumulator rings and fast cycling synchrotrons, and typical applications are for pulsed spallation neutron sources, heavy ion fusion storage ring drivers, and booster injectors for high energy proton and ion facilities. Aspects of the three topics are discussed in the paper. {copyright} {ital 1996 American Institute of Physics.}
Innovative Navigation Systems to Support Digital Geophysical Mapping
2004-02-01
9 Figure 8. Blackhawk/ Applanix GPS/INS System.................................................................10 Figure 9. Figure-Eight Traverse...Vulcan/LaserStation Line-of-sight laser Parsons Trimble INS/GPS DGPS and inertia guidance Blackhawk Applanix INS/GPS DGPS and inertia guidance...The Applanix Positioning and Orientation System for Land Survey (POS/LS) was used for the Phase I work. The system is similar to the Parsons
Near Surface Magnetic Survey for Investigating the Cultural Relics in Suchon, Gongju, Korea
NASA Astrophysics Data System (ADS)
Islam, M. R.; Tiampo, K.; Suh, M.; Abdallatif, T. F.
2009-05-01
A magnetic study by the FM256 Fluxgate Gradiometer was conducted in Suchon, Gongju to measure the vertical magnetic gradient of the Earth's magnetic field and to give further details of the shallow section. The region was divided into two separate areas. The first study area measured 40m by 20m while the second study area was 20m x 20m. Each was subsequently divided into four grids of dimension 20m by 10m and 10m by 10m respectively. Measurements of the vertical magnetic gradient were conducted through successive zigzag traverses. The sample-interval and the traverse-interval were set to specifically record small anomalies at a high resolution. A total of 3200 readings were measured at the first study area and 1600 at the second study area. The data have been downloaded, presented and processed through the Geoplot software to remove the spikes, grid discontinuities, and traverses stripes, and also to enhance the display and smooth the data using the Gaussian low-pass filtering techniques. The vertical gradient of the processed data over the second study area ranges from -34nT to + 21nT, while it ranges from -36nT to + 62nT at the first study area. The gradiometer results defined several positive and negative magnetic anomalies, which revealed the existence of several subsurface features of different shapes and sizes. A comparison between the processed magnetic images suggest that the subsurface features may include a room structure (e.g. hut), a cave-shaped stone chamber tomb, an accumulation of potteries and porcelains common in the Baekje period in the ancient Korean history. The biggest anomaly (3 m in diameter) may illuminate a quartzite tomb chamber. As a result, the study area has great archaeological interest.
Vertical view Apollo 16 Descartes landing sites as photographed by Apollo 14
1971-01-12
S72-00147 (January 1972) --- An almost vertical view of the Apollo 16 Descartes landing area, as photographed from the Apollo 14 spacecraft. Overlays are provided to point out extravehicular activity (EVA) Lunar Roving Vehicle (LRV) traverse routes and the nicknames of features. Hold picture with South Ray Crater in lower left corner. North will then be at the top. The Roman numerals indicate EVA numbers and the Arabic numbers point out stations or traverse stops.
The Role of Geologic Mapping in NASA PDSI Planning
NASA Astrophysics Data System (ADS)
Williams, D. A.; Skinner, J. A.; Radebaugh, J.
2017-12-01
Geologic mapping is an investigative process designed to derive the geologic history of planetary objects at local, regional, hemispheric or global scales. Geologic maps are critical products that aid future exploration by robotic spacecraft or human missions, support resource exploration, and provide context for and help guide scientific discovery. Creation of these tools, however, can be challenging in that, relative to their terrestrial counterparts, non-terrestrial planetary geologic maps lack expansive field-based observations. They rely, instead, on integrating diverse data types wth a range of spatial scales and areal coverage. These facilitate establishment of geomorphic and geologic context but are generally limited with respect to identifying outcrop-scale textural details and resolving temporal and spatial changes in depositional environments. As a result, planetary maps should be prepared with clearly defined contact and unit descriptions as well as a range of potential interpretations. Today geologic maps can be made from images obtained during the traverses of the Mars rovers, and for every new planetary object visited by NASA orbital or flyby spacecraft (e.g., Vesta, Ceres, Titan, Enceladus, Pluto). As Solar System Exploration develops and as NASA prepares to send astronauts back to the Moon and on to Mars, the importance of geologic mapping will increase. In this presentation, we will discuss the past role of geologic mapping in NASA's planetary science activities and our thoughts on the role geologic mapping will have in exploration in the coming decades. Challenges that planetary mapping must address include, among others: 1) determine the geologic framework of all Solar System bodies through the systematic development of geologic maps at appropriate scales, 2) develop digital Geographic Information Systems (GIS)-based mapping techniques and standards to assist with communicating map information to the scientific community and public, 3) develop public awareness of the role and application of geologic map-information to the resolution of national issues relevant to planetary science and eventual off-planet resource assessments, 4) use topical science to drive mapping in areas likely to be determined vital to the welfare of endeavors related to planetary science and exploration.
Reconnaissance of radioactive rocks of Maine
Nelson, John M.; Narten, Perry F.
1951-01-01
The state of Maine was traversed with car-mounted Geiger-Mueller equipment in the late summer of 1948 and the radioactivity of approximately 4,600 miles of road was logged. All samples were analyzed, both in the field by comparing the radioactivity of each sample to the radioactivity of a stranded measured with a simple scaling modification of a portable counter, and in the Geological Survey’s Trace Elements Section Washington Laboratory. Differences between both types of analyses were negligible. The maximum equivalent uranium content of the most radioactive rocks thus analyzed was 0.008 percent. A 1,400-square-mile abnormally radioactive province in southwestern Maine was outlined. The outcrop data obtained from car traversing are evaluated statistically. Cumulative frequency distribution curves are drawn to show the distribution of outcrops at various levels of radioactivity, and straight-line extensions are made to show to maximum probable grade for various rock types and areas in Maine. A maximum grade of 0.055 percent equivalent uranium is thus predicted for the entire state. This prediction necessarily is a broad generalization because large areas of Main are inaccessible for car traversing. A concept of evaluation of an area for possible mineral deposits is proposed on the basis of lithology, and observed and indicated ranges in grade.
NASA Technical Reports Server (NTRS)
Zuber, Maria T.; Smith, David E.; Asmar, Sami W.; Alomon; Konopliv, Alexander S.; Lemoine, Frank G.; Melosh, H. Jay; Neumann, Gregory A.; Phillips. Roger J.; Solomon, Sean C.;
2012-01-01
The Gravity Recovery And Interior Laboratory (GRAIL) mission, a component of NASA's Discovery Program, launched successfully from Cape Canaveral Air Force Station on September 10, 2011. The dual spacecraft traversed independent, low-energy trajectories to the Moon via the EL-1 Lagrange point and inserted into elliptical, 11.5-hour polar orbits around the Moon on December 31, 2011, and January 1, 2012. The spacecraft are currently executing a series of maneuvers to circularize their orbits at 55-km mean altitude. Once the mapping orbit is achieved, the spacecraft will undergo additional maneuvers to align them into mapping configuration. The mission is on track to initiate the Science Phase on March 8, 2012.
NASA Astrophysics Data System (ADS)
Galve, J. P.; Castañeda, C.; Gutiérrez, F.
2015-11-01
Subsidence was measured for the first time on railway tracks in the central sector of Ebro Valley (NE Spain) using Differential Synthetic Aperture Radar Interferometry (DInSAR) techniques. This area is affected by evaporite karst and the analysed railway corridors traverse active sinkholes that produce deformations in these infrastructures. One of the railway tracks affected by slight settlements is the Madrid-Barcelona high-speed line, a form of transport infrastructure highly vulnerable to ground deformation processes. Our analysis based on DInSAR measurements and geomorphological surveys indicates that this line shows dissolution-induced subsidence and compaction of anthropogenic deposits (infills and embankments). Significant sinkhole-related subsidence was also measured by DInSAR techniques on the Castejón-Zaragoza conventional railway line. This study demonstrates that DInSAR velocity maps, coupled with detailed geomorphological surveys, may help in the identification of the railway track sections that are affected by active subsidence.
Learning and Prediction of Slip from Visual Information
NASA Technical Reports Server (NTRS)
Angelova, Anelia; Matthies, Larry; Helmick, Daniel; Perona, Pietro
2007-01-01
This paper presents an approach for slip prediction from a distance for wheeled ground robots using visual information as input. Large amounts of slippage which can occur on certain surfaces, such as sandy slopes, will negatively affect rover mobility. Therefore, obtaining information about slip before entering such terrain can be very useful for better planning and avoiding these areas. To address this problem, terrain appearance and geometry information about map cells are correlated to the slip measured by the rover while traversing each cell. This relationship is learned from previous experience, so slip can be predicted remotely from visual information only. The proposed method consists of terrain type recognition and nonlinear regression modeling. The method has been implemented and tested offline on several off-road terrains including: soil, sand, gravel, and woodchips. The final slip prediction error is about 20%. The system is intended for improved navigation on steep slopes and rough terrain for Mars rovers.
Highly Asynchronous VisitOr Queue Graph Toolkit
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pearce, R.
2012-10-01
HAVOQGT is a C++ framework that can be used to create highly parallel graph traversal algorithms. The framework stores the graph and algorithmic data structures on external memory that is typically mapped to high performance locally attached NAND FLASH arrays. The framework supports a vertex-centered visitor programming model. The frameworkd has been used to implement breadth first search, connected components, and single source shortest path.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-10
... milepost 680.06 near Dawson on the Hull Oakes Lead (together, the Line). The Line traverses United States..., although the milepost where the Hull Oakes Lead connects to the Bailey Branch at Alpine Junction is correct... mileposts. The legend on the map indicates an increase in the mileage of the Hull Oakes Lead from 6.85 to 7...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Evans, K.L.; Shibasaki, Yoshiro; Devon, R.S.
1995-08-10
Forty-nine clones derived by microdissection of a schizophrenia-associated t(1;11)(q42.1;q14.3) breakpoint region have been assigned by somatic cell hybrid mapping to seven discrete intervals on the long arm of human chromosome 11. Eleven of the clones were shown to map to a small region immediately distal to the translocation breakpoint on 11q. A 3-Mb contiguous clone map of this region was established by isolation of corresponding YAC recombinants. The contig was oriented and shown to traverse the translocation breakpoint by FISH and microsatellite marker analysis. This contig will facilitate the isolation of candidate sequences whose expression may be affected by themore » translocation. 28 refs., 4 figs., 3 tabs.« less
Neighbourhood social trust and youth perceptions of safety during daily activities.
Flynn, Kalen; Richmond, Therese S; Branas, Charles C; Wiebe, Douglas J
2017-10-07
Exposure to adverse neighbourhood conditions can negatively impact adolescent well-being and perceived safety. However, the impact of neighbourhood social trust on perceived safety is largely unknown. We studied 139 adolescent men to investigate how their perceptions of safety varied as a function of social trust levels in the neighbourhoods they traversed; neighbourhoods that were not necessarily their own. Adolescents mapped their minute-by-minute activities over a recent day and rated their perceived safety on a 10-point scale during in-person interviews. Neighbourhood social trust was measured via a citywide random sample survey. Mixed effects regression showed that, compared with their safety perceptions when in areas of low social trust, older adolescents were 73% more likely to feel unsafe when in areas of medium social trust, and 89% more likely to feel unsafe when in areas of high social trust. Inverse relationships between neighbourhood social trust and adolescents' perceived safety highlight the complex interplay between youth, environmental contexts and safety. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Vision Based Localization in Urban Environments
NASA Technical Reports Server (NTRS)
McHenry, Michael; Cheng, Yang; Matthies, Larry
2005-01-01
As part of DARPA's MARS2020 program, the Jet Propulsion Laboratory developed a vision-based system for localization in urban environments that requires neither GPS nor active sensors. System hardware consists of a pair of small FireWire cameras and a standard Pentium-based computer. The inputs to the software system consist of: 1) a crude grid-based map describing the positions of buildings, 2) an initial estimate of robot location and 3) the video streams produced by each camera. At each step during the traverse the system: captures new image data, finds image features hypothesized to lie on the outside of a building, computes the range to those features, determines an estimate of the robot's motion since the previous step and combines that data with the map to update a probabilistic representation of the robot's location. This probabilistic representation allows the system to simultaneously represent multiple possible locations, For our testing, we have derived the a priori map manually using non-orthorectified overhead imagery, although this process could be automated. The software system consists of two primary components. The first is the vision system which uses binocular stereo ranging together with a set of heuristics to identify features likely to be part of building exteriors and to compute an estimate of the robot's motion since the previous step. The resulting visual features and the associated range measurements are software component, a particle-filter based localization system. This system uses the map and the then fed to the second primary most recent results from the vision system to update the estimate of the robot's location. This report summarizes the design of both the hardware and software and will include the results of applying the system to the global localization of a robot over an approximately half-kilometer traverse across JPL'S Pasadena campus.
Analysis of the Gulf of Mexico's Veracruz-Havana Route of La Flota de la Nueva España
NASA Astrophysics Data System (ADS)
Lugo-Fernández, A.; Ball, D. A.; Gravois, M.; Horrell, C.; Irion, J. B.
2007-06-01
During colonial times, an active maritime trade existed between Spain and the New World, with convoys sailing annually to and from Mexico and returning via Havana, Cuba, after wintering in America. A database constructed from secondary and open sources revealed that Spanish vessels were sailing over open waters along a northern path near Louisiana and a southern path across the central Gulf of Mexico. These routes were traversed in about one month and scheduling for the convoy was based on an understanding of the Americas’ meteorological and oceanographic climate. However, other factors may also have been involved in the directional layout of the routes. Today these ancient routes crisscross planning areas for oil and gas lease sales in the US Exclusive Economic Zone and the information presented in this article may aid in identifying areas where historic shipwrecks may lie. Maps and documents found during this study helped piece together the evolution of our understanding of the Gulf of Mexico surface circulation and how this knowledge influenced sailing during colonial times.
Carbon stock corridors to mitigate climate change and promote biodiversity in the tropics
NASA Astrophysics Data System (ADS)
Jantz, Patrick; Goetz, Scott; Laporte, Nadine
2014-02-01
A key issue in global conservation is how biodiversity co-benefits can be incorporated into land use and climate change mitigation activities, particularly those being negotiated under the United Nations to reduce emissions from tropical deforestation and forest degradation. Protected areas have been the dominant strategy for tropical forest conservation and they have increased substantially in recent decades. Avoiding deforestation by preserving carbon stored in vegetation between protected areas provides an opportunity to mitigate the effects of land use and climate change on biodiversity by maintaining habitat connectivity across landscapes. Here we use a high-resolution data set of vegetation carbon stock to map corridors traversing areas of highest biomass between protected areas in the tropics. The derived corridors contain 15% of the total unprotected aboveground carbon in the tropical region. A large number of corridors have carbon densities that approach or exceed those of the protected areas they connect, suggesting these are suitable areas for achieving both habitat connectivity and climate change mitigation benefits. To further illustrate how economic and biological information can be used for corridor prioritization on a regional scale, we conducted a multicriteria analysis of corridors in the Legal Amazon, identifying corridors with high carbon, high species richness and endemism, and low economic opportunity costs. We also assessed the vulnerability of corridors to future deforestation threat.
Visualizing the geology of lake trout spawning sites; northern Lake Michigan
Dartnell, Peter; Barnes, Peter; Gardner, James V.; Lee, Kristen
2006-01-01
Geologists and biologists are working together to understand the links between lake floor geology (composition and shape) and the distribution of lake trout throughout their life cycle. Lake floor geology is one of the main factors determining where lake trout spawn, feed, and hide. In support of ongoing research to study Lake Michigan trout habitats, the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers mapped the morphology of principle lake trout spawning sites. Using the Army Corps of Engineer's SHOALS airborne lidar (Light Detection and Ranging) system we mapped six regions in Northern Lake Michigan in order to identify ideal spawning regions composed of shallow, clean, gravel/cobble substrate, adjacent to deeper water. Lidar mapping systems, which use laser pulses to measure water depths from an airplane, are now available to map the nearshore lake morphology at meter-scale detail. Maps generated from the bathymetric data are used to define regions with smooth homogeneous substrate, regions with higher relief, and mixed regions with both smooth and rough relief. This morphologic information combined with sediment samples and direct bottom observations enable geologists to map areas with rougher relief composed of rock outcrop, boulders, and cobbles, as well as smooth regions covered with sand or mud. This information helps biologists, fishery managers, and ecologists visualize the lake floor in significant detail which promotes better fishery management, species protection, and habitat identification. These maps present the maps and discuss the geology of the six lake trout spawning sites mapped by the lidar system. Where the mapping approached land, aerial photography of the land is combined with the bathymetric data to help visualize the scale of the offshore features. Map and perspective views of Boulder Reef, Hog Island Reef, and Little Traverse Bay are shown on sheet 1, whereas map and perspective views of Trout and High Island Shoal, Gull Island Reef, and Dahlia Shoal are shown on sheet 2. Additional information, bathymetric data, imagery, and metadata are available online at http://geopubs.wr.usgs.gov/open-file/of03-120/.
Visualizing the geology of lake trout spawning sites, northern Lake Michigan
Dartnell, Peter; Barnes, Peter; Gardner, James V.; Lee, Kristen
2004-01-01
Geologists and biologists are working together to understand the links between lake floor geology (composition and shape) and the distribution of lake trout throughout their life cycle. Lake floor geology is one of the main factors determining where lake trout spawn, feed, and hide. In support of ongoing research to study Lake Michigan trout habitats, the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers mapped the morphology of principle lake trout spawning sites. Using the Army Corps of Engineer's SHOALS airborne lidar (Light Detection and Ranging) system we mapped six regions in Northern Lake Michigan in order to identify ideal spawning regions composed of shallow, clean, gravel/cobble substrate, adjacent to deeper water. Lidar mapping systems, which use laser pulses to measure water depths from an airplane, are now available to map the nearshore lake morphology at meter-scale detail. Maps generated from the bathymetric data are used to define regions with smooth homogeneous substrate, regions with higher relief, and mixed regions with both smooth and rough relief. This morphologic information combined with sediment samples and direct bottom observations enable geologists to map areas with rougher relief composed of rock outcrop, boulders, and cobbles, as well as smooth regions covered with sand or mud. This information helps biologists, fishery managers, and ecologists visualize the lake floor in significant detail which promotes better fishery management, species protection, and habitat identification. These maps present the maps and discuss the geology of the six lake trout spawning sites mapped by the lidar system. Where the mapping approached land, aerial photography of the land is combined with the bathymetric data to help visualize the scale of the offshore features. Map and perspective views of Boulder Reef, Hog Island Reef, and Little Traverse Bay are shown on sheet 1, whereas map and perspective views of Trout and High Island Shoal, Gull Island Reef, and Dahlia Shoal are shown on sheet 2. Additional information, bathymetric data, imagery, and metadata are available online at http://geopubs.wr.usgs.gov/open-file/of03-120/.
Climate change velocity underestimates climate change exposure in mountainous regions
Dobrowski, Solomon Z.; Parks, Sean A.
2016-01-01
Climate change velocity is a vector depiction of the rate of climate displacement used for assessing climate change impacts. Interpreting velocity requires an assumption that climate trajectory length is proportional to climate change exposure; longer paths suggest greater exposure. However, distance is an imperfect measure of exposure because it does not quantify the extent to which trajectories traverse areas of dissimilar climate. Here we calculate velocity and minimum cumulative exposure (MCE) in degrees Celsius along climate trajectories for North America. We find that velocity is weakly related to MCE; each metric identifies contrasting areas of vulnerability to climate change. Notably, velocity underestimates exposure in mountainous regions where climate trajectories traverse dissimilar climates, resulting in high MCE. In contrast, in flat regions velocity is high where MCE is low, as these areas have negligible climatic resistance to movement. Our results suggest that mountainous regions are more climatically isolated than previously reported. PMID:27476545
Development of Intelligent Unmanned Systems
2011-05-01
statistical analysis on the terrain map. The data points are stored in the corresponding cells of the Traversability Grid as a linked list of 3-D Cartesian...allowed for multiple configurations of specified data to be as flexible as possible. For example, when an object is being created the knowledge store ...library was also used for querying and storing spatial data . It provided many geometric abstractions necessary such as overlap and intersects
Spiking, Bursting, and Population Dynamics in a Network of Growth Transform Neurons.
Gangopadhyay, Ahana; Chakrabartty, Shantanu
2018-06-01
This paper investigates the dynamical properties of a network of neurons, each of which implements an asynchronous mapping based on polynomial growth transforms. In the first part of this paper, we present a geometric approach for visualizing the dynamics of the network where each of the neurons traverses a trajectory in a dual optimization space, whereas the network itself traverses a trajectory in an equivalent primal optimization space. We show that as the network learns to solve basic classification tasks, different choices of primal-dual mapping produce unique but interpretable neural dynamics like noise shaping, spiking, and bursting. While the proposed framework is general enough, in this paper, we demonstrate its use for designing support vector machines (SVMs) that exhibit noise-shaping properties similar to those of modulators, and for designing SVMs that learn to encode information using spikes and bursts. It is demonstrated that the emergent switching, spiking, and burst dynamics produced by each neuron encodes its respective margin of separation from a classification hyperplane whose parameters are encoded by the network population dynamics. We believe that the proposed growth transform neuron model and the underlying geometric framework could serve as an important tool to connect well-established machine learning algorithms like SVMs to neuromorphic principles like spiking, bursting, population encoding, and noise shaping.
Mars exploration rover geologic traverse by the spirit rover in the plains of Gusev crater, Mars
Crumpler, L.S.; Squyres, S. W.; Arvidson, R. E.; Bell, J.F.; Blaney, D.; Cabrol, N.A.; Christensen, P.R.; DesMarais, D.J.; Farmer, J.D.; Fergason, R.; Golombek, M.P.; Grant, F.D.; Grant, J. A.; Greeley, R.; Hahn, B.; Herkenhoff, K. E.; Hurowitz, J.A.; Knudson, A.T.; Landis, G.A.; Li, R.; Maki, J.; McSween, H.Y.; Ming, D. W.; Moersch, J.E.; Payne, M.C.; Rice, J.W.; Richter, L.; Ruff, S.W.; Sims, M.; Thompson, S.D.; Tosca, N.; Wang, A.; Whelley, P.; Wright, S.P.; Wyatt, M.B.
2005-01-01
The Spirit rover completed a 2.5 km traverse across gently sloping plains on the floor of Gusev crater from its location on the outer rim of Bonneville crater to the lower slopes of the Columbia Hills, Mars. Using the Athena suite of instruments in a transect approach, a systematic series of overlapping panoramic mosaics, remote sensing observations, surface analyses, and trenching operations documented the lateral variations in landforms, geologic materials, and chemistry of the surface throughout the traverse, demonstrating the ability to apply the techniques of field geology by remote rover operations. Textures and shapes of rocks within the plains are consistent with derivation from impact excavation and mixing of the upper few meters of basaltic lavas. The contact between surrounding plains and crater ejecta is generally abrupt and marked by increases in clast abundance and decimeter-scale steps in relief. Basaltic materials of the plains overlie less indurated and more altered rock types at a time-stratigraphic contact between the plains and Columbia Hills that occurs over a distance of one to two meters. This implies that regional geologic contacts are well preserved and that Earth-like field geologic mapping will be possible on Mars despite eons of overturn by small impacts. ?? 2005 Geological Society of America.
NASA Astrophysics Data System (ADS)
Chan, L. Y.; Liu, Y. M.; Lee, S. C.; Chan, C. Y.
Vehicle exhaust is the major source of pollutant in modern cities. About half of Hong Kong residents are living in suburban or rural areas. They need to traverse through tunnels, highways, urban street canyons and other road conditions in different landuse areas when they traverse to work in urban centres or new towns. Also, there is increasing traffic, especially trucks across the border between Hong Kong and mainland China via several border highways. This study helps us in assessing the exposure level of suburban and cross border commuters. Carbon monoxide (CO) is used as a tracer for traffic emission. An experimental vehicle traversing major commuting corridors were used to measure CO levels in different landuse and roadway microenvironments including tunnels and highways. The air samples were taken simultaneously at the outside and inside of a travelling vehicle. Result indicates that the pattern of fluctuation of the out-vehicle and in-vehicle CO level vary with different landuse areas. The variation pattern of in-vehicle CO level is closely related to that of out-vehicle level. The effects of the out-vehicle CO concentration on the in-vehicle CO concentration under different roadway conditions in various landuse categories are examined. There is an indication that external air pollutants penetrated into the in-vehicle compartment through car body cracks, ventilation system. From our observation, the exhaust of a nearby petrol vehicle contributed significantly to the in-vehicle CO level. The use of low standard of diesel fuel from Shenzhen in mainland China leads to higher CO level near border area.
Astronauts Young and Duke begin simulated lunar surface traverse at KSC
NASA Technical Reports Server (NTRS)
1972-01-01
Astronauts John W. Young, right, Apollo 16 commander, and Charles M. Duke Jr., lunar module pilot, prepare to begin a simulated traverse in a training area at the Kennedy Space Center (KSC). Among the experiments to fly on Apollo 16 is the soil mechanics (S-200) experiment, or self-recording penetrometer, a model of which is held here by Duke. A training model of the Lunar Roving Vehicle (LRV) is parked between the two crewmen (30694); Young and Duke maneuver a training version of the LRV about a field at KSC simulated to represent the lunar surface (30695).
Multi-Resolution Indexing for Hierarchical Out-of-Core Traversal of Rectilinear Grids
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pascucci, V.
2000-07-10
The real time processing of very large volumetric meshes introduces specific algorithmic challenges due to the impossibility of fitting the input data in the main memory of a computer. The basic assumption (RAM computational model) of uniform-constant-time access to each memory location is not valid because part of the data is stored out-of-core or in external memory. The performance of most algorithms does not scale well in the transition from the in-core to the out-of-core processing conditions. The performance degradation is due to the high frequency of I/O operations that may start dominating the overall running time. Out-of-core computing [28]more » addresses specifically the issues of algorithm redesign and data layout restructuring to enable data access patterns with minimal performance degradation in out-of-core processing. Results in this area are also valuable in parallel and distributed computing where one has to deal with the similar issue of balancing processing time with data migration time. The solution of the out-of-core processing problem is typically divided into two parts: (i) analysis of a specific algorithm to understand its data access patterns and, when possible, redesign the algorithm to maximize their locality; and (ii) storage of the data in secondary memory with a layout consistent with the access patterns of the algorithm to amortize the cost of each I/O operation over several memory access operations. In the case of a hierarchical visualization algorithms for volumetric data the 3D input hierarchy is traversed to build derived geometric models with adaptive levels of detail. The shape of the output models is then modified dynamically with incremental updates of their level of detail. The parameters that govern this continuous modification of the output geometry are dependent on the runtime user interaction making it impossible to determine a priori what levels of detail are going to be constructed. For example they can be dependent from external parameters like the viewpoint of the current display window or from internal parameters like the isovalue of an isocontour or the position of an orthogonal slice. The structure of the access pattern can be summarized into two main points: (i) the input hierarchy is traversed level by level so that the data in the same level of resolution or in adjacent levels is traversed at the same time and (ii) within each level of resolution the data is mostly traversed at the same time in regions that are geometrically close. In this paper I introduce a new static indexing scheme that induces a data layout satisfying both requirements (i) and (ii) for the hierarchical traversal of n-dimensional regular grids. In one particular implementation the scheme exploits in a new way the recursive construction of the Z-order space filling curve. The standard indexing that maps the input nD data onto a 1D sequence for the Z-order curve is based on a simple bit interleaving operation that merges the n input indices into one index n times longer. This helps in grouping the data for geometric proximity but only for a specific level of detail. In this paper I show how this indexing can be transformed into an alternative index that allows to group the data per level of resolution first and then the data within each level per geometric proximity. This yields a data layout that is appropriate for hierarchical out-of-core processing of large grids.« less
McNamara, D.E.; Walter, W.R.
2001-01-01
In this paper we describe a technique for mapping the lateral variation of Lg characteristics such as Lg blockage, efficient Lg propagation, and regions of very high attenuation in the Middle East, North Africa, Europe and the Mediterranean regions. Lg is used in a variety of seismological applications from magnitude estimation to identification of nuclear explosions for monitoring compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). These applications can give significantly biased results if the Lg phase is reduced or blocked by discontinuous structure or thin crust. Mapping these structures using quantitative techniques for determining Lg amplitude attenuation can break down when the phase is below background noise. In such cases Lg blockage and inefficient propagation zones are often mapped out by hand. With our approach, we attempt to visually simplify this information by imaging crustal structure anomalies that significantly diminish the amplitude of Lg. The visualization of such anomalies is achieved by defining a grid of cells that covers the entire region of interest. We trace Lg rays for each event/ station pair, which is simply the great circle path, and attribute to each cell a value equal to the maximum value of the Lg/P-coda amplitude ratio for all paths traversing that particular cell. The resulting map, from this empirical approach, is easily interpreted in terms of crustal structure and can successfully image small blockage features often missed by analysis of raypaths alone. This map can then be used to screen out events with blocked Lg prior to performing Q tomography, and to avoid using Lg-based methods of event identification for the CTBT in regions where they cannot work. For this study we applied our technique to one of the most tectonically complex regions on the earth. Nearly 9000 earthquake/station raypaths, traversing the vast region comprised of the Middle East, Mediterranean, Southern Europe and Northern Africa, have been analyzed. We measured the amplitude of Lg relative to the P-coda and mapped the lateral variation of Lg propagation efficiency. With the relatively dense coverage provided by the numerous crossing paths we are able to map out the pattern of crustal heterogeneity that gives rise to the observed character of Lg propagation. We observe that the propagation characteristics of Lg within the region of interest are very complicated but are readily correlated with the different tectonic environments within the region. For example, clear strong Lg arrivals are observed for paths crossing the stable continental interiors of Northern Africa and the Arabian Shield. In contrast, weakened to absent Lg is observed for paths crossing much of the Middle East, and Lg is absent for paths traversing the Mediterranean. Regions that block Lg transmission within the Middle East are very localized and include the Caspian Sea, the Iranian Plateau and the Red Sea. Resolution is variable throughout the region and strongly depends on the distribution of seismicity and recording stations. Lg propagation is best resolved within the Middle East where regions of crustal heterogeneity on the order of 100 km are imaged (e.g., South Caspian Sea and Red Sea). Crustal heterogeneity is resolvable but is poorest in seismically quiescent Northern Africa.
NASA Technical Reports Server (NTRS)
Eppler, Dean B.
2015-01-01
The SP Mountain area of the San Francisco Volcanic Field, AZ, has been used as an analog mission development site for NASA since 1998. This area consists of basaltic cinder cones, lava flows and maar craters that have been active since mid-Miocene, with the youngest events occurring within the last 10,000 years. The area has been used because its geologic and topographic resemblance to lunar and Martian terrains provides an ideal venue for testing hardware and science operations practices that might be employed on planetary surfaces, as well as training astronauts in field geology. Analog operations have often led to insights that spurred new scientific investigations. Most recently, an investigation of the 7504 cone was initiated due to perceptions that Apollo-style traverse plans executed during the Desert RATS 2010 mission had characterized the area incorrectly, leading to concerns that the Apollo traverse planning process was scientifically flawed. This investigation revealed a complex history of fissure eruptions of lava and cinders, cinder cone development, a cone-fill-and-spill episode, extensive rheomorphic lava flow initiation and emplacement, and cone sector collapse that led to a final lava flow. This history was not discernible on pre-RATS mission photogeology, although independent analysis of RATS 2010 data and samples develped a "75% complete solution" that validated the pre-RATS mission planning and Apollo traverse planning and execution. The study also pointed out that the development of scientific knowledge with time in a given field area is not linear, but may follow a functional form that rises steeply in the early period of an investigation but flattens out in the later period, asymptotically approaching a theoretical "complete knowledge" point that probably cannot be achieved. This implies that future human missions must be prepared to shift geographic areas of investigation regularly if significant science returns are to be forthcoming.
NASA Astrophysics Data System (ADS)
Bleacher, J. E.; Eppler, D. B.; Needham, D. H.; Evans, C. A.; Skinner, J. A.; Feng, W.
2015-12-01
The SP Mountain area of the San Francisco Volcanic Field, AZ, has been used as an analog mission development site for NASA since 1998. This area consists of basaltic cinder cones, lava flows and maar craters that have been active since mid-Miocene, with the youngest events occurring within the last 10,000 years. The area has been used because its geologic and topographic resemblance to lunar and Martian terrains provides an ideal venue for testing hardware and science operations practices that might be employed on planetary surfaces, as well as training astronauts in field geology. Analog operations have often led to insights that spurred new scientific investigations. Most recently, an investigation of the 7504 cone was initiated due to perceptions that Apollo-style traverse plans executed during the Desert RATS 2010 mission had characterized the area incorrectly, leading to concerns that the Apollo traverse planning process was scientifically flawed. This investigation revealed a complex history of fissure eruptions of lava and cinders, cinder cone development, a cone-fill-and-spill episode, extensive rheomorphic lava flow initiation and emplacement, and cone sector collapse that led to a final lava flow. This history was not discernible on pre-RATS mission photogeology, although independent analysis of RATS 2010 data and samples develped a "75% complete solution" that validated the pre-RATS mission planning and Apollo traverse planning and execution. The study also pointed out that the development of scientific knowledge with time in a given field area is not linear, but may follow a functional form that rises steeply in the early period of an investigation but flattens out in the later period, asymptotically approaching a theoretical "complete knowledge" point that probably cannot be achieved. This implies that future human missions must be prepared to shift geographic areas of investigation regularly if significant science returns are to be forthcoming.
Integrated geophysical study of the geothermal system in the southern part of Nisyros Island, Greece
NASA Astrophysics Data System (ADS)
Lagios, E.; Apostolopoulos, G.
1995-10-01
The study of the high-enthalpy geothermal field of Nisyros Island is of great importance, because of the planned construction of a geothermal power station. The purpose of the applied geophysical surveys — gravity, SP, VLF and audio-magnetotelluric — in southernmost Nisyros was to investigate the major and minor faulting zones which are geothermally active, i.e. whether geothermal fluid circulation occurs in these zones. The survey lines, four parallel traverses of about 1500 m length, were chosen to be almost transverse to the main faults of the area. The SP method was the main reconnaissance technique, with the VLF and gravity measurements correlating with the "SP model". Previously proposed SP data acquisition and reduction techniques were used, followed by a 2-D interpretation of the SP map which apparently locates the position of the fracture zones (geothermally active). The SP and VLF anomalies are believed to be generated by the same source (subsurface flow of fluid, heat and ions). Hence, at the place of a vertical geothermal fluid circulation zone, the curve of SP dipole-like anomaly changes its behaviour and the curve of the VLF anomaly takes maximum values for the in-phase component and minimum values for the out-of-phase component. On the VLF map of the survey area, the zones detected with the SP interpretation coincide with the maximum values of the VLF in-phase component. The geothermal fluid circulation zones, detected by the SP method, appear to be well correlated with corresponding features derived from the gravity and the AMT surveys. In particular, the AMT soundings indicate two zones of geothermal fluid circulation instead of the one the SP method detected in the central part of the investigated area.
NASA Technical Reports Server (NTRS)
Friedman, J. D. (Principal Investigator)
1974-01-01
The author has identified the following significant results. By the end of 1973, aerial infrared scanner traverses for thermal anomaly recordings of all Cascade Range volcanoes were essentially completed. Amplitude level slices of the Mount Baker anomalies were completed and compiled at a scale of 1:24,000, thus producing, for the first time, an accurate map of the distribution and intensity of thermal activity on Mount Baker. The major thermal activity is concentrated within the crater south of the main summit and although it is characterized by intensive solfataric activity and warm ground, it is largely subglacial, causing the development of sizable glacier perforation features. The outgoing radiative flux from the east breach anomalies is sufficient to account for the volume of ice melted to form the glacier perforations. DCP station 6251 has been monitoring a thermally anomalous area on the north slope of Mount Baker. The present thermal activity of Mount Baker accounts for continuing hydrothermal alteration in the crater south of the main summit and recurrent debris avalanches from Sherman Peak on its south rim. The infrared anomalies mapped as part of the experiment SR 251 are considered the basic evidence of the subglacial heating which was the probable triggering mechanism of an avalanche down Boulder Glacier on August 20-21, 1973.
NASA Astrophysics Data System (ADS)
Kayode, J. S.; Adelusi, A. O.; Nawawi, M. N. M.; Bawallah, M.; Olowolafe, T. S.
2016-07-01
This paper presents a geophysical surveying for groundwater identification in a resistive crystalline basement hard rock in Isuada area, Southwestern Nigeria. Very low frequency (VLF) electromagnetic and electrical resistivity geophysical techniques combined with well log were used to characterize the concealed near surface conductive structures suitable for groundwater accumulation. Prior to this work; little was known about the groundwater potential of this area. Qualitative and semi-quantitative interpretations of the data collected along eight traverses at 20 m spacing discovered conductive zones suspected to be fractures, faults, and cracks which were further mapped using Vertical Electrical Sounding (VES) technique. Forty VES stations were utilized using Schlumberger configurations with AB/2 varying from 1 to 100 m. Four layers i.e. the top soil, the weathered layer, the partially weathered/fractured basement and the fresh basement were delineated from the interpreted resistivity curves. The weathered layers constitute the major aquifer unit in the area and are characterized by moderately low resistivity values which ranged between about 52 Ωm and 270 Ωm while the thickness varied from 1 to 35 m. The depth to the basement and the permeable nature of the weathered layer obtained from both the borehole and the hand-dug wells was used to categorize the groundwater potential of the study area into high, medium and low ratings. The groundwater potential map revealed that about 45% of the study area falls within the low groundwater potential rating while about 10% constitutes the medium groundwater potential and the remaining 45% constitutes high groundwater potential. The low resistivity, thick overburden, and fractured bedrock constitute the aquifer units and the series of basement depressions identified from the geoelectric sections as potential conductive zones appropriate for groundwater development.
Real-space Berry phases: Skyrmion soccer (invited)
NASA Astrophysics Data System (ADS)
Everschor-Sitte, Karin; Sitte, Matthias
2014-05-01
Berry phases occur when a system adiabatically evolves along a closed curve in parameter space. This tutorial-like article focuses on Berry phases accumulated in real space. In particular, we consider the situation where an electron traverses a smooth magnetic structure, while its magnetic moment adjusts to the local magnetization direction. Mapping the adiabatic physics to an effective problem in terms of emergent fields reveals that certain magnetic textures, skyrmions, are tailormade to study these Berry phase effects.
Fast, Automated, Photo realistic, 3D Modeling of Building Interiors
2016-09-12
project, we developed two algorithmic pipelines for GPS-denied indoor mobile 3D mapping using an ambulatory backpack system. By mounting scanning...equipment on a backpack system, a human operator can traverse the interior of a building to produce a high-quality 3D reconstruction. In each of our...Unlimited UU UU UU UU 12-09-2016 1-May-2011 30-Jun-2015 Final Report: Fast, Automated, Photo-realistic, 3D Modeling of Building Interiors (ATTN
Design of a Mars rover and sample return mission
NASA Technical Reports Server (NTRS)
Bourke, Roger D.; Kwok, Johnny H.; Friedlander, Alan
1990-01-01
The design of a Mars Rover Sample Return (MRSR) mission that satisfies scientific and human exploration precursor needs is described. Elements included in the design include an imaging rover that finds and certifies safe landing sites and maps rover traverse routes, a rover that operates the surface with an associated lander for delivery, and a Mars communications orbiter that allows full-time contact with surface elements. A graph of MRSR candidate launch vehice performances is presented.
Real-space Berry phases: Skyrmion soccer (invited)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Everschor-Sitte, Karin, E-mail: karin@physics.utexas.edu; Sitte, Matthias
Berry phases occur when a system adiabatically evolves along a closed curve in parameter space. This tutorial-like article focuses on Berry phases accumulated in real space. In particular, we consider the situation where an electron traverses a smooth magnetic structure, while its magnetic moment adjusts to the local magnetization direction. Mapping the adiabatic physics to an effective problem in terms of emergent fields reveals that certain magnetic textures, skyrmions, are tailormade to study these Berry phase effects.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ross, R.S.
1989-06-01
For a vehicle operating across arbitrarily-contoured terrain, finding the most fuel-efficient route between two points can be viewed as a high-level global path-planning problem with traversal costs and stability dependent on the direction of travel (anisotropic). The problem assumes a two-dimensional polygonal map of homogeneous cost regions for terrain representation constructed from elevation information. The anisotropic energy cost of vehicle motion has a non-braking component dependent on horizontal distance, a braking component dependent on vertical distance, and a constant path-independent component. The behavior of minimum-energy paths is then proved to be restricted to a small, but optimal set of traversalmore » types. An optimal-path-planning algorithm, using a heuristic search technique, reduces the infinite number of paths between the start and goal points to a finite number by generating sequences of goal-feasible window lists from analyzing the polygonal map and applying pruning criteria. The pruning criteria consist of visibility analysis, heading analysis, and region-boundary constraints. Each goal-feasible window lists specifies an associated convex optimization problem, and the best of all locally-optimal paths through the goal-feasible window lists is the globally-optimal path. These ideas have been implemented in a computer program, with results showing considerably better performance than the exponential average-case behavior predicted.« less
Incidence of Mink, Mustela vison, and River Otter, Lutra canadensis, in a Highly Urbanized Area
Mech, L.D.
2003-01-01
Mink (Mustela vison) frequently inhabited or traversed a residential, business, and industrial part of the Twin Cities, Minnesota, with little water or natural vegetation. At least one River Otter (Lutra canadensis) also resided on a small pond on a golf course in the area for several winter months.
Incidence of mink, Mustela vison, and river otter, Lutra canadensis, in a highly urbanized area
Mech, L. David
2003-01-01
Mink (Musela vison ) frequently inhabited or traversed a residential, business, and industrial part of the Twin Cities, Minnesota, with little water or natural vegetation. At least one River Otter (Lutra canadensis ) also resided on a small pond on a golf course in the area for several winter months.
A geochemical study of the Rio Pantanos area, Department of Antioquia, Colombia preliminary report
Alminas, Henry V.; Mosier, Elwin L.
1972-01-01
Geochemical sampling in the Western Cordillera has delineated an 18 km 2 area anomalous in copper, molybdenum, and silver. Highly anomalous metal contents are found in stream sediment, soil, and outcrop samples collected within this area. The area is underlain by intrusive granodiorite to quartz diorite that has porphyritic and granitoid phases. Most of the outcrop samples contain disseminated pyrite, chalcopyrite, and bornite. A geochemical reconnaissance sampling program in the Western Cordillera, formulated by Andros Jimeno V., Director, Instituto National de Investigaciones Geologico-Mineras (INGEOMINAS), and Earl M. Irving, U. S. Geological Survey (USGS) Chief of Party in Colombia, was carried out from 1969 to 1971 by geologists of the INGEOMINAS office in Medellin. This work was part of a cooperative program of INGEOMINAS and the USGS sponsored by the Government of Colombia and the Agency for International Development, U. S. Department of State. Seventeen generally east-trending traverses were completed across the Western Cordillera. These traverses, generally paralleling major drainages, cross the range at intervals of 10 to 30 km.
Investigation of the Rocket Induced Flow Field in a Rectangular Duct
NASA Technical Reports Server (NTRS)
Landrum, D. Brian; Thames, Mignon; Parkinson, Doug; Gautney, Serena; Hawk, Clark
1999-01-01
Several tests were performed on a one-sixth scale Rocket Based Combined Cycle (RBCC) engine model at the University of Alabama in Huntsville. The UAH RBCC facility consists of a rectangular duct with a vertical strut mounted in the center. The scaled strut consists of two supersonic rocket nozzles with an embedded vertical turbine between the rocket nozzles. The tests included mass flow, flow visualization and horizontal pressure traverses. The mass flow test indicated a c:hoked condition when the rocket chamber pressure is between 200 psi and 300 psi. The flow visualization tests narrowed the rocket chamber pressure range from, 250 psi to 300 psi. Also, from this t.est, an assumption of a minimum
NASA Astrophysics Data System (ADS)
Gourcerol, B.; Kontak, D. J.; Thurston, P. C.; Petrus, J. A.
2018-01-01
Quantitative laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) element distribution maps combined with traverse mode analyses have been acquired on various sulfides (pyrite, pyrrhotite, arsenopyrite) from three Canadian Algoma-type BIF-hosted gold deposits ( 4 Moz Au Meadowbank, ≥ 2.8 Moz Au Meliadine district, 6 Moz Au Musselwhite). These data, in conjunction with detailed petrographic and SEM-EDS observations, provide insight into the nature and relative timing of gold events, the presence and implication of trace element zoning regarding crystallization processes, and elemental associations that fingerprint gold events. Furthermore, the use of an innovative method of processing the LA-ICP-MS data in map and traverse modes, whereby the results are fragmented into time-slice data, to generate various binary plots (Ag versus Ni) provides a means to identify elemental associations (Te, Bi) not otherwise apparent. This integrated means of treating geochemical data, along with petrography, allows multiple gold events and remobilization processes to be recognized and their elemental associations determined. The main gold event in each of these deposits is characterized by the coupling of an As-Se-Te-Ag element association coincident with intense stratabound sulfide-replacement of the Fe-rich host rock. Additionally, the data indicate presence of a later remobilization event, which upgraded the Au tenor, as either non-refractory or refractory type, along fracture networks due to the ingress of subsequent base metal-bearing metamorphic fluids (mainly a Pb-Bi association). Furthermore, the data reveal a stratigraphic influence, as reflected in the elemental associations and the elemental enrichments observed and the nature of the sulfide phase hosting the gold mineralization (arsenopyrite versus pyrite).
Movements of a male Canada lynx crossing the greater Yellowstone Area, including highways
John R. Squires; Robert Oakleaf
2005-01-01
From 1999-2001, a male Canada lynx engaged in yearly exploratory movements across the greater Yellowstone area including the Teton Wilderness Area and Yellowstone National Park. For three consecutive summers, the lynx traversed a similar path in a northwesterly direction from the animalâs home range in the Wyoming Range near Big Piney, Wyoming, to as far as...
NASA Astrophysics Data System (ADS)
Behrendt, J. C.
2006-12-01
When 12 countries established scientific stations in Antarctica for the 1957-58 International Geophysical Year (IGY), the Cold War was at its height, seven countries had made claims in Antarctica, and the Antarctic Treaty was a few years in the future. I was a graduate student assistant seismologist, on the unexplored Filchner- Ronne Ice Shelf as part of the only major field project of the U.S. Antarctic program. Starting in 1957, the U.S. began a series of oversnow traverses making seismic reflection ice soundings (and other geophysical measurements) and glaciological studies to determine the thickness and budget of the Antarctic Ice Sheet. The U.S.S.R. and France made similar traverses coordinated through the IGY. Although geology and topographic mapping were not part of the IGY program because of the claims issue and the possibility of mineral resources, the oversnow traverse parties did geologic work, where unknown mountains were discovered. The oversnow traverses continued through 1966 and resulted in an excellent first approximation of the snow surface elevation, ice thickness and bed topography of Antarctica, as well as the mean annual temperature of that era and snow accumulation. The vacuum tube dictated the logistics of the oversnow traverse program. Seismic equipment including heavy batteries weighed about 500 kg. Therefore a Sno-Cat tracked vehicle was needed to carry this load. Usually three such vehicles were needed for safety. Because about 3 l/km of fuel were consumed by each Sno-Cat, about 100 kg/day of fuel per vehicle was required. A resupply flight could carry only ~600 kg/flight (varying greatly as to range and type of aircraft).The Filchner Ice Shelf Traverse, 1957-58, in which I participated, encountered many crevasses. Vehicles broke through thin snow bridges and one man fell deep into a crevasse. Fortunately there were no deaths and only one serious injury resulting from crevasse accidents on the U.S. oversnow traverse program. Starting in 1958 and continuing to 1964 the oversnow traverses were complimented by an airborne geophysical program comprising widely spaced landings for seismic reflection ice sounding and 75,000 km of widely spaced aeromagnetic and snow surface elevation profiles. The airborne profiles were concentrated over the West Antarctic Ice Sheet (WAIS) and along the length of the Transantarctic Mountains, and approximately defined the vast extent of a late Cenozoic volcanic province beneath the WAIS associated with the unknown West Antarctic rift system. There were numerous hazards encountered using these U.S. Navy planes of opportunity including denting a wing on a hidden mountain and a crash on one occasion killing the geophysicist (Edward Thiel) and four others. There was an aircraft death rate of 3.8 deaths per year in the U.S. program from 1955-66. The oversnow and airborne traverses of the IGY-IGC period employed the inductive method of scientific research with only the general objectives of defining the Antarctic Ice Sheet as to surface elevation, thickness, snow accumulation and temperature. In contrast, Antarctic research today employs deductive logic with narrowly defined objectives and testing of hypotheses. This change has been necessary because of expense, and competition of proposals by many scientists. Nonetheless something has been lost by this approach, and there is still the need for "exploration" types of research is the still unknown vast continent of Antarctica.
Wallace, Heather Julie; McDonald, Susan; Belton, Suzanne; Miranda, Agueda Isolina; da Costa, Eurico; da Conceicao Matos, Livio; Henderson, Helen; Taft, Angela
2018-06-01
Maternal mortality remains a significant public health challenge for Timor-Leste. Although access to quality family planning measures may greatly reduce such deaths, consideration of indigenous perceptions, and how they influence reproductive health decision-making and behavior, is crucial if health services are to provide initiatives that are accepted and helpful in improving reproductive health outcomes. We aimed to demonstrate that body mapping is an effective method to traverse language and culture to gain emic insights and indigenous worldviews. The authors' two qualitative research projects (2013 and 2015) used a decolonizing methodology in four districts of Timor-Leste, body mapping with 67 men and 40 women to illuminate ethno-physiology and indigenous beliefs about conception, reproduction, and contraception. Body mapping provided a beneficial conduit for identifying established indigenous reproductive perceptions, understandings, and vocabulary, plus fears surrounding contraception. This may inform health service provision and engagement, ultimately improving the reproductive health of community members.
Geologic Map of the Boxley Quadrangle, Newton and Madison Counties, Arkansas
Hudson, Mark R.; Turner, Kenzie J.
2007-01-01
This map summarizes the geology of the Boxley 7.5-minute quadrangle in the Ozark Plateaus region of northern Arkansas. Geologically, the area lies on the southern flank of the Ozark dome, an uplift that exposes oldest rocks at its center in Missouri. Physiographically, the Boxley quadrangle lies within the Boston Mountains, a high plateau region underlain by Pennsylvanian sandstones and shales. Valleys of the Buffalo River and its tributaries expose an approximately 1,600-ft-(490-m-)thick sequence of Ordovician, Mississippian, and Pennsylvanian carbonate and clastic sedimentary rocks that have been mildly deformed by a series of faults and folds. Part of Buffalo National River, a park encompassing the Buffalo River and adjacent land that is administered by the National Park Service, extends through the eastern part of the quadrangle. Mapping for this study was conducted by field inspection of numerous sites and was compiled as a 1:24,000-scale geographic information system (GIS) database. Locations and elevation sites were determined with the aid of a global positioning satellite receiver and a hand-held barometric altimeter. Hill-shade-relief and slope maps derived from a U.S. Geological Survey 10-m digital elevation model as well as orthophotos were used to help trace ledge-forming units between field traverses within the Upper Mississippian and Pennsylvanian part of the stratigraphic sequence. Strike and dip of beds were typically measured along stream drainages or at well-exposed ledges. Structure contours were constructed on the top of the Boone Formation and the base of a prominent sandstone unit within the Bloyd Formation based on elevations of control points as well as other limiting information on their maximum or minimum elevations.
Rovers for intelligent, agile traverse of challenging terrain
NASA Technical Reports Server (NTRS)
Schenker, P.; Huntsberger, T.; Pirjanian, P.; Dubowsky, S.; Iagnemma, K.; Sujan, V.
2003-01-01
Planetary surface mobility has to date been limited to benign locations. If rover systems could be developed for more challenging terrain, e.g., sloped and irregularly feathered areas, then planetary science opportunities would be greatly expanded.
Documenting AUTOGEN and APGEN Model Files
NASA Technical Reports Server (NTRS)
Gladden, Roy E.; Khanampompan, Teerapat; Fisher, Forest W.; DelGuericio, Chris c.
2008-01-01
A computer program called "autogen hypertext map generator" satisfies a need for documenting and assisting in visualization of, and navigation through, model files used in the AUTOGEN and APGEN software mentioned in the two immediately preceding articles. This program parses autogen script files, autogen model files, PERL scripts, and apgen activity-definition files and produces a hypertext map of the files to aid in the navigation of the model. This program also provides a facility for adding notes and descriptions, beyond what is in the source model represented by the hypertext map. Further, this program provides access to a summary of the model through variable, function, sub routine, activity and resource declarations as well as providing full access to the source model and source code. The use of the tool enables easy access to the declarations and the ability to traverse routines and calls while analyzing the model.
NASA Technical Reports Server (NTRS)
Hoffman, Stephen J. (Editor); Voels, Stephen A. (Editor)
2012-01-01
Topics covered include: Antarctic Exploration Parallels for Future Human Planetary Exploration: Science Operations Lessons Learned, Planning, and Equipment Capabilities for Long Range, Long Duration Traverses; Parallels Between Antarctic Travel in 1950 and Planetary Travel in 2050 (to Accompany Notes on "The Norwegian British-Swedish Antarctic Expedition 1949-52"); My IGY in Antarctica; Short Trips and a Traverse; Geologic Traverse Planning for Apollo Missions; Desert Research and Technology Studies (DRATS) Traverse Planning; Science Traverses in the Canadian High Arctic; NOR-USA Scientific Traverse of East Antarctica: Science and Logistics on a Three-Month Expedition Across Antarctica's Farthest Frontier; A Notional Example of Understanding Human Exploration Traverses on the Lunar Surface; and The Princess Elisabeth Station.
Barlow, Roger A.; Nardi, Mark R.; Reyes, Betzaida
2008-01-01
Sussex County, Delaware, occupies a 938-square-mile area of low relief near sea level in the Atlantic Coastal Plain. The county is bounded on the east by the Delaware Bay and the Atlantic Ocean, including a barrier-island system, and inland bays that provide habitat for valuable living resources. Eastern Sussex County is an area of rapid population growth with a long-established beach-resort community, where land elevation is a key factor in determining areas that are appropriate for development. Of concern to State and local planners are evacuation routes inland to escape flooding from severe coastal storms, as most major transportation routes traverse areas of low elevation that are subject to inundation. The western half of the county is typically rural in character, and land use is largely agricultural with some scattered forest land cover. Western Sussex County has several low-relief river flood-prone areas, where accurate high-resolution elevation data are needed for Federal Emergency Management Agency (FEMA) Digital Flood Insurance Rate Map (DFIRM) studies. This fact sheet describes the methods and techniques used to collect and process LiDAR elevation data, the generation of the digital elevation model (DEM) and the 2-foot contours, and the quality-assurance procedures and results. It indicates where to view metadata on the data sets and where to acquire bare-earth mass points, DEM data, and contour data.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thomas, D.M.; Malinconico, L.L. Jr.
1993-03-01
This project involves the geophysical modeling of the structural relationships between the Precambrian Reading Prong rocks and the Paleozoic sedimentary cover rocks near Easton, Pennsylvania. The Precambrian rocks have generally been assumed to have been emplaced on the Paleozoic sequence along a shallow thrust fault. However, at present time the attitude of the faults bordering the Precambrian terranes are all very steeply dipping. This was explained by the subsequent folding of the whole sequence during later orogenic activity. The objective of this work is to determine the attitude and depth of the fault contact between the Precambrian crystalline rocks andmore » the Paleozoic sedimentary rocks. A series of traverses (each separated by approximately one mile) were established perpendicular to the strike of the Precambrian rocks. Along each traverse both gravity and magnetic readings were taken at 0.2 kilometer intervals. The data were reduced and presented as profiles and contour maps. Both the magnetic and gravity data show positive anomalies that correlate spatially with the location of the Precambrian rocks. The gravity data have a long wavelength regional trend increasing to the north with a shorter wavelength anomaly of 2 milligals which coincides with the Precambrian rocks. The magnetic data have a single positive anomaly of almost 1,000 gammas which also coincides with the Precambrian terrane. These data will now be used to develop two dimensional density and susceptibility models of the area. From these models, the thickness of each formation and the structural relationships between them, as well as the attitude and depth of the fault contact will be determined.« less
NASA Astrophysics Data System (ADS)
Bayewu, Olateju O.; Oloruntola, Moroof O.; Mosuro, Ganiyu O.; Laniyan, Temitope A.; Ariyo, Stephen O.; Fatoba, Julius O.
2017-12-01
The geophysical assessment of groundwater in Awa-Ilaporu, near Ago Iwoye southwestern Nigeria was carried out with the aim of delineating probable areas of high groundwater potential. The area falls within the Crystalline Basement Complex of southwestern Nigeria which is predominantly underlain by banded gneiss, granite gneiss and pegmatite. The geophysical investigation involves the very low frequency electromagnetic (VLF-EM) and Vertical Electrical Sounding (VES) methods. The VLF-EM survey was at 10 m interval along eight traverses ranging between 290 and 700 m in length using ABEM WADI VLF-EM unit. The VLF-EM survey was used to delineate areas with conductive/fractured zones. Twenty-three VES surveys were carried out with the use of Campus Ohmega resistivity meter at different location and at locations areas delineated as high conductive areas by VLF-EM survey. The result of VLF-EM survey along its traverse was used in delineating high conductive/fractured zones, it is, however, in agreement with the delineation of the VES survey. The VES results showed 3-4 geoelectric layers inferred as sandy topsoil, sandy clay, clayey and fractured/fresh basement. The combination of these two methods, therefore, helped in resolving the prospecting location for the groundwater yield in the study area.
An asynchronous traversal engine for graph-based rich metadata management
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dai, Dong; Carns, Philip; Ross, Robert B.
Rich metadata in high-performance computing (HPC) systems contains extended information about users, jobs, data files, and their relationships. Property graphs are a promising data model to represent heterogeneous rich metadata flexibly. Specifically, a property graph can use vertices to represent different entities and edges to record the relationships between vertices with unique annotations. The high-volume HPC use case, with millions of entities and relationships, naturally requires an out-of-core distributed property graph database, which must support live updates (to ingest production information in real time), low-latency point queries (for frequent metadata operations such as permission checking), and large-scale traversals (for provenancemore » data mining). Among these needs, large-scale property graph traversals are particularly challenging for distributed graph storage systems. Most existing graph systems implement a "level synchronous" breadth-first search algorithm that relies on global synchronization in each traversal step. This performs well in many problem domains; but a rich metadata management system is characterized by imbalanced graphs, long traversal lengths, and concurrent workloads, each of which has the potential to introduce or exacerbate stragglers (i.e., abnormally slow steps or servers in a graph traversal) that lead to low overall throughput for synchronous traversal algorithms. Previous research indicated that the straggler problem can be mitigated by using asynchronous traversal algorithms, and many graph-processing frameworks have successfully demonstrated this approach. Such systems require the graph to be loaded into a separate batch-processing framework instead of being iteratively accessed, however. In this work, we investigate a general asynchronous graph traversal engine that can operate atop a rich metadata graph in its native format. We outline a traversal-aware query language and key optimizations (traversal-affiliate caching and execution merging) necessary for efficient performance. We further explore the effect of different graph partitioning strategies on the traversal performance for both synchronous and asynchronous traversal engines. Our experiments show that the asynchronous graph traversal engine is more efficient than its synchronous counterpart in the case of HPC rich metadata processing, where more servers are involved and larger traversals are needed. Furthermore, the asynchronous traversal engine is more adaptive to different graph partitioning strategies.« less
An asynchronous traversal engine for graph-based rich metadata management
Dai, Dong; Carns, Philip; Ross, Robert B.; ...
2016-06-23
Rich metadata in high-performance computing (HPC) systems contains extended information about users, jobs, data files, and their relationships. Property graphs are a promising data model to represent heterogeneous rich metadata flexibly. Specifically, a property graph can use vertices to represent different entities and edges to record the relationships between vertices with unique annotations. The high-volume HPC use case, with millions of entities and relationships, naturally requires an out-of-core distributed property graph database, which must support live updates (to ingest production information in real time), low-latency point queries (for frequent metadata operations such as permission checking), and large-scale traversals (for provenancemore » data mining). Among these needs, large-scale property graph traversals are particularly challenging for distributed graph storage systems. Most existing graph systems implement a "level synchronous" breadth-first search algorithm that relies on global synchronization in each traversal step. This performs well in many problem domains; but a rich metadata management system is characterized by imbalanced graphs, long traversal lengths, and concurrent workloads, each of which has the potential to introduce or exacerbate stragglers (i.e., abnormally slow steps or servers in a graph traversal) that lead to low overall throughput for synchronous traversal algorithms. Previous research indicated that the straggler problem can be mitigated by using asynchronous traversal algorithms, and many graph-processing frameworks have successfully demonstrated this approach. Such systems require the graph to be loaded into a separate batch-processing framework instead of being iteratively accessed, however. In this work, we investigate a general asynchronous graph traversal engine that can operate atop a rich metadata graph in its native format. We outline a traversal-aware query language and key optimizations (traversal-affiliate caching and execution merging) necessary for efficient performance. We further explore the effect of different graph partitioning strategies on the traversal performance for both synchronous and asynchronous traversal engines. Our experiments show that the asynchronous graph traversal engine is more efficient than its synchronous counterpart in the case of HPC rich metadata processing, where more servers are involved and larger traversals are needed. Furthermore, the asynchronous traversal engine is more adaptive to different graph partitioning strategies.« less
NASA Astrophysics Data System (ADS)
Roberti, Gioachino; van Wyk de vries, Benjamin; Ward, Brent; Clague, John; Friele, Pierre; Perotti, Luigi; Giardino, Marco
2016-04-01
This study examines the large landslide that occurred at Mt. Meager, 200 km NNW of Vancouver, British Columbia, Canada, on August 6, 2010. We studied the source area and deposits to reconstruct the failure of the south flank of Mt. Meager from slow deformation to catastrophic collapse, the subsequent transformation into a debris avalanche, and the 11 km run-out. We use a Structure from Motion (SfM) photogrammetric approach and processed both historical British Columbia Provincial airphotos (1948, 1962, 1964-1965, 1973, 1981, 1990, and 2006) and digital images taken with a commercial camera during low-level helicopter traverses. The SfM products have been used to calculate volumes and the geometry of the south flank of Mt. Meager before and after the catastrophic failure, and to produce an orthophoto that we have used to map and describe the deposit. Oblique helicopter photos provide information on the scar geometry and rock units exposed by the failure. The SfM-derived orthophoto and ground observations allowed us to map deposit facies, lithologies, and structures, including thrust, normal, and strike-slip faults. We identified five sub-areas in the accumulation zone based on the association of facies and deformation structures. Based on our interpretation of the remotely sensed data and ground observations, we propose that the landslide had two main rheological phases: one richer in water and highly mobile, and another massive and water-poor. The water-rich phase spread quickly and superelevated high on valley walls as it moved down valley. It left a discontinuous veneer of debris, typically <1 m thick. The main, unsaturated mass moved more slowly and left a thicker (up to about 20 m) deposit with hummocks and brittle-ductile faults and shear zone in the distal part of the run-out zone.
NASA Astrophysics Data System (ADS)
Fersch, Alisa; Walker, C.
2012-01-01
Light pollution is a well-known problem for astronomers. It is also gaining attention as an ecological issue. The federally endangered Lesser Long-Nosed Bat (Leptonycteris cursoae) resides for part of the year near Tucson, Arizona. It is possible that this species tends to avoid light. Excess artificial light would therefore interfere with the bats’ flight patterns and foraging habits. In order to test this hypothesis, we quantified night sky brightness with data from the citizen-science campaign GLOBE at Night. Using direct measurements taken with a Sky Quality Meter (SQM), we created a contour map of the artificial night sky brightness around Tucson. When this map is compared to the approximate flight paths of the lesser long-nosed bat, we can see that the bats do appear to be avoiding the brightest area of Tucson. We also used logistic regression to analyze what combination of ecological variables (ecoregion, vegetation cover, landform and light) best describes the observed spatial distribution of lesser long-nosed bats. Of the models that were tested, light alone was not a good predictor of the bat presence or absence. However, light in addition to vegetation and ecoregion was the best model. This information can be useful for making decisions about lighting codes in areas of the city that the bats tend to traverse. The contour map of light pollution in Tucson will be useful for both future astronomy and ecology studies and can also be used for public outreach about light pollution. Fersch was supported by the NOAO/KPNO Research Experiences for Undergraduates (REU) Program which is funded by the National Science Foundation Research Experiences for Undergraduates Program and the Department of Defense ASSURE program through Scientific Program Order No. 13 (AST-0754223) of the Cooperative Agreement No. AST-0132798 between the Association of Universities for Research in Astronomy (AURA) and the NSF.
Microrover Research for Exploration of Mars
NASA Technical Reports Server (NTRS)
Hayati, Samad; Volpe, Richard; Backes, Paul; Balaram, J.; Welch, Richard
1996-01-01
There is great interest in the science community to explore Mars by using microrovers that carry seveal science instruments and are capable of traversing long distances[1]. NASA has planned six additional missions to Mars for 2001, 2003, and 2005. There is an excellent chance that rovers will be utilized in some of these missions. Such rovers would traverse to sites separated by seveal kilometers and place instruments against outcrops or loose rocks, search an area for a sample of interest, and collect rocks and soil samples for return to Earth (2005 mission). Our research objectives are to develop technologies that enable such scenarios within the mission constraints of mass, power, volume, and cost.
APOLLO 17 - INFLIGHT Experiment Equipment
1972-11-28
S72-53952 (November 1972) --- The Traverse Gravimeter Experiment (S-199), with cover removed, which will be used by the Apollo 17 crewmen at the Taurus-Littrow landing site. The purposes of this experiment are to make a high accuracy relative survey of the lunar gravitational field in the lunar landing area and to make an Earth-moon gravity tie. Specific experiment objectives related to these purposes are to: (1) measure the value of gravity, relative to the value at a lunar base station, at selected known locations along the lunar traverse; (2) measure the value of gravity at a known point on the lunar surface (base station) relative to the value of gravity at a known point on Earth.
Sacks, Benjamin N.; Ernest, Holly B.; Boydston, Erin E.
2006-01-01
Although coyotes (Canis latrans) are wellknown for their adaptability to human-modified landscapes (Riley et al. 2003), as with any medium to large-sized carnivore, they typically avoid highly urbanized areas (Crooks 2002), preferring instead to use habitat fragments linked by vegetated corridors (Tigas et al. 2002). However, recent observations of coyotes in San Francisco indicate their willingness to traverse even the most densely urbanized terrain (Rubenstein 2003). Herein we use DNA to show, in an extreme example, that an adult male coyote caught in the northern tip of the San Francisco peninsula traversed the 2-km Golden Gate Bridge, potentially linking historically distinct coyote populations.
Thinning response in 110-year-old Douglas-fir
Richard L. Williamson
1966-01-01
A study was established in 1952 near Boundary Creek in the Panther Creek area on the Wind River experimental Forest near Carson, Wash. Site index averages 140, and aspect is westerly at elevations around 2,000 to 2,400 feet. Two minor drainages traverse the study area from east to west, creating various northwesterly and southwesterly aspects. The almost pure Douglas-...
NASA Astrophysics Data System (ADS)
Litvak, Maxim
2017-04-01
During more than 4 years MSL Curiosity rover (landed in Gale crater in August 2012) is traveling toward sedimentary layered mound deposited with phyllosilicates and hematite hydrated minerals. Curiosity already traversed more than 14 km and identified lacustrine deposits left from ancient lakes filled Gale area in early history of Mars. Along the traverse the Curiosity rover discovered unique signatures regarding how the Mars environment changed from ancient warm and wet conditions and probably habitable environment to the modern cold and dry climate. We have summarized numerous measurements from the Dynamic Albedo of Neutron (DAN) instrument on Curiosity rover to overview variations of subsurface bound water distribution from the wet to the dry locations, compared it with other MSL measurements and with possible distribution of hydrated minerals and sequence of geological units travelled by Curiosity. We have also performed joint analysis of water and chlorine distributions and compared bulk (down to 0.5 m depth) equivalent chlorine concentrations measured by DAN throughout the Gale area and APXS observations of corresponding local surface targets and drill fines.
NASA Astrophysics Data System (ADS)
Behrendt, J. C.
2003-12-01
In 1956 I sailed for Antarctica to spend 18 months as a graduate student participating in geophysical-glaciological investigations, as part of the 18-month IGY. This led to a career in geophysics, which has taken me to all of the continents and oceans. As we approach the IPY 2007, the changes in technology and our understanding of the earth over the past half century are breathtaking to contemplate. Although 70 countries participated in IGY, the disciplines were restricted to geophysics. Originally the Third Polar Year, the name was changed to IGY in 1952, at the suggestion of Sydney Chapman. The geographical area comprised the entire earth. The highest priority was given to "problems requiring concurrent synoptic observations at many points involving cooperative observations by many stations." One category was reserved for research on topics such as ocean levels, weather patterns, and the distribution of glacier ice "to establish basic information for subsequent comparison at later epochs." IPY 2007 seems such an epoch. A major international efforts was concentrated in Antarctica, although only 12 counties participated. Glaciology, seismology, auroral studies, ionospheric soundings, magnetic field measurements, and other solar-terrestrial, and meteorological observations comprised the scientific station activities. The only major field activities away from the stations were the oversnow geophysical-glaciological traverses, which made seismic measurements of ice thickness and other ice properties; gravity and magnetic anomaly profiles; and determination of snow accumulation and mean annual temperature. The most intensive of the oversnow traverse programs were those of the U.S. and USSR. Geology and topographic mapping were excluded from the Antarctica because of potential complications due to territorial claims and the possibility of mineral resource discoveries. Despite this, significant geologic findings, such as the discovery of the Dufek intrusion, were made by glaciologists and geophysicists with geologic training. Biology was not an IGY discipline, but even in this case, noted ornithologist, Carl Ekland (at Wilkes Station), carried out significant investigations of skuas. Physical oceanographic investigations resulted in geologic and biological sampling of the sea floor as well. A very few of the significant accomplishments of the IGY include the discovery of the Van Allen belts (the symbol of the IGY was a satellite circling the earth); the observation (at Mauna Loa) and recognition of the rapid global increase in carbon dioxide; the first major models of Arctic sea ice formation, decay, and drift; and the mapping of the midocean ridge system. In Antarctica, a first approximation of the mass of the ice sheet including the order of magnitude thicker ice than previously known (4 km) was a highlight. A baseline of mean annual temperatures measured (to about 0.1 degree accuracy) at about 40 km intervals along thousands of km of oversnow traverses was defined. Three World Data Centers were established; scientific results and data were deposited and made freely available to all. The peaceful international cooperation in Antarctica led directly to the signing of the Antarctic Treaty in 1959, with the first disarmament and freedom of inspection and scientific investigations clauses in history, covering a large area of the earth. I anticipate even greater international scientific cooperation from the IPY 2007. A new generation of polar scientists was developed as a result of IGY; a few of us are still active in Antarctic research. A similar result will provide continuity for the next 50 years.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brumbaugh, William D.; Cook, Kenneth L.
During the summers of 1975 and 1976, a gravity survey was conducted in the Cove Fort - Sulphurdale KGRA and north Mineral Mountains area, Millard and Beaver counties, Utah. The survey consisted of 671 gravity stations covering an area of about 1300 km{sup 2}, and included two orthogonal gravity profiles traversing the area. The gravity data are presented as a terrain-corrected Bouguer gravity anomaly map with a contour interval of 1 mgal and as an isometric three-dimensional gravity anomaly surface. Selected anomaly separation techniques were applied to the hand-digitized gravity data (at 1-km intervals on the Universal Transverse Mercator grid)more » in both the frequency and space domains, including Fourier decomposition, second vertical derivative, strike-filter, and polynomial fitting analysis, respectively. Residual gravity gradients of 0.5 to 8.0 mgal/km across north-trending gravity contours observed through the Cove Fort area, the Sulphurdale area, and the areas east of the East Mineral Mountains, along the west flanks of the Tushar Mountains, and on both the east and west flanks of the north Mineral Mountains, were attributed to north-trending Basin and Range high-angle faults. Gravity highs exist over the community of Black Rock area, the north Mineral Mountains, the Paleozoic outcrops in the east Cove Creek-Dog Valley-White Sage Flats areas, the sedimentary thrust zone of the southern Payant Range, and the East Mineral Mountains. The gravity lows over north Milford Valley, southern Black Rock Desert, Cunningham Wash, and northern Beaver Valley are separated from the above gravity highs by steep gravity gradients attributed to a combination of crustal warping and faulting. A gravity low with a closure of 2 mgal corresponds with Sulphur Cove, a circular topographic features containing sulphur deposits.« less
Design guidelines for raised and traversable medians in urban areas.
DOT National Transportation Integrated Search
1983-01-01
Major urban and suburban streets must provide a high level of service for through traffic as well as access to abutting properties. To an extent, the provisions of traffic service and the accommodation of access needs are conflicting functions that a...
Body-terrain interaction affects large bump traversal of insects and legged robots.
Gart, Sean W; Li, Chen
2018-02-02
Small animals and robots must often rapidly traverse large bump-like obstacles when moving through complex 3D terrains, during which, in addition to leg-ground contact, their body inevitably comes into physical contact with the obstacles. However, we know little about the performance limits of large bump traversal and how body-terrain interaction affects traversal. To address these, we challenged the discoid cockroach and an open-loop six-legged robot to dynamically run into a large bump of varying height to discover the maximal traversal performance, and studied how locomotor modes and traversal performance are affected by body-terrain interaction. Remarkably, during rapid running, both the animal and the robot were capable of dynamically traversing a bump much higher than its hip height (up to 4 times the hip height for the animal and 3 times for the robot, respectively) at traversal speeds typical of running, with decreasing traversal probability with increasing bump height. A stability analysis using a novel locomotion energy landscape model explained why traversal was more likely when the animal or robot approached the bump with a low initial body yaw and a high initial body pitch, and why deflection was more likely otherwise. Inspired by these principles, we demonstrated a novel control strategy of active body pitching that increased the robot's maximal traversable bump height by 75%. Our study is a major step in establishing the framework of locomotion energy landscapes to understand locomotion in complex 3D terrains.
A Study of Parallels Between Antarctica South Pole Traverse Equipment and Lunar/Mars Surface Systems
NASA Technical Reports Server (NTRS)
Mueller, Robert P.; Hoffman, Stephen, J.; Thur, Paul
2010-01-01
The parallels between an actual Antarctica South Pole re-supply traverse conducted by the National Science Foundation (NSF) Office of Polar Programs in 2009 have been studied with respect to the latest mission architecture concepts being generated by the United States National Aeronautics and Space Administration (NASA) for lunar and Mars surface systems scenarios. The challenges faced by both endeavors are similar since they must both deliver equipment and supplies to support operations in an extreme environment with little margin for error in order to be successful. By carefully and closely monitoring the manifesting and operational support equipment lists which will enable this South Pole traverse, functional areas have been identified. The equipment required to support these functions will be listed with relevant properties such as mass, volume, spare parts and maintenance schedules. This equipment will be compared to space systems currently in use and projected to be required to support equivalent and parallel functions in Lunar and Mars missions in order to provide a level of realistic benchmarking. Space operations have historically required significant amounts of support equipment and tools to operate and maintain the space systems that are the primary focus of the mission. By gaining insight and expertise in Antarctic South Pole traverses, space missions can use the experience gained over the last half century of Antarctic operations in order to design for operations, maintenance, dual use, robustness and safety which will result in a more cost effective, user friendly, and lower risk surface system on the Moon and Mars. It is anticipated that the U.S Antarctic Program (USAP) will also realize benefits for this interaction with NASA in at least two areas: an understanding of how NASA plans and carries out its missions and possible improved efficiency through factors such as weight savings, alternative technologies, or modifications in training and operations.
Autonomous Navigation by a Mobile Robot
NASA Technical Reports Server (NTRS)
Huntsberger, Terrance; Aghazarian, Hrand
2005-01-01
ROAMAN is a computer program for autonomous navigation of a mobile robot on a long (as much as hundreds of meters) traversal of terrain. Developed for use aboard a robotic vehicle (rover) exploring the surface of a remote planet, ROAMAN could also be adapted to similar use on terrestrial mobile robots. ROAMAN implements a combination of algorithms for (1) long-range path planning based on images acquired by mast-mounted, wide-baseline stereoscopic cameras, and (2) local path planning based on images acquired by body-mounted, narrow-baseline stereoscopic cameras. The long-range path-planning algorithm autonomously generates a series of waypoints that are passed to the local path-planning algorithm, which plans obstacle-avoiding legs between the waypoints. Both the long- and short-range algorithms use an occupancy-grid representation in computations to detect obstacles and plan paths. Maps that are maintained by the long- and short-range portions of the software are not shared because substantial localization errors can accumulate during any long traverse. ROAMAN is not guaranteed to generate an optimal shortest path, but does maintain the safety of the rover.
NASA Astrophysics Data System (ADS)
Tominaga, M.; Beinlich, A.; Tivey, M.; Andrade Lima, E.; Weiss, B. P.
2012-12-01
The contribution of lower oceanic crust and upper mantle to marine magnetic anomalies has long been recognized, but the detailed magnetic character of this non-volcanic source layer remains to be fully defined. Here, we report preliminary results of a magnetic survey and source characterization of a "carbonated" oceanic Moho (petrological "Mohorovicic discontinuity") sequence observed at the Linnajavri Serpentinite Complex (LSC), northern Norway. The LSC is located at 67° 36'N and 16° 24'E within the upper Allochthon of the Norwegian Caledonides and represents a dismembered ophiolite. Particularly in the southern ("Ridoalggicohkka") area of the LSC, gabbro, serpentinite and its talc-carbonate (soapstone) and quartz-carbonate (listvenite) altered equivalents are extraordinarily well-exposed [1]. An intact oceanic Moho is exposed here, despite its complex tectonic setting. The small degree of arctic rock weathering (≤ 2 mm weathering surface) allowed for detailed regional-scale surface magnetic mapping across alteration fronts (serpentinite-soapstone; soapstone-listvenite) and lithological contacts (soapstone-gabbro). Magnetic mapping was conducted using a handheld 3-axis magnetometer, surface-towed resistivity meter and Teka surface magnetic susceptometer with sample spacing of 1 m. Geophysical field mapping was combined with petrological observations and scanning SQUID microscopy (SM) mapping conducted on thin sections from rock samples that were drilled along the survey lines. Regional scale magnetic mapping indicates that the total magnetic field across both the "carbonated" Moho and the soapstone-serpentinite interfaces show higher frequency changes in their magnetic anomaly character and amplitudes than the surface-towed resistivity data. SQUID microscopy mapping of both natural remanence magnetization (NRM) and anhysteretic remanence magnetization (ARM) on gabbro, serpentinite, soapstone, and listvenite samples, with a sensor-sample separation of ˜190 μm, show that the distribution of microscopically measurable ferromagnetic and possibly sulfide minerals produces a different bulk intensity for each of the rock types. SM vector magnetic field maps of these samples also reveal that the magnetization associated with these grains (observed as dipole-like fields in SM maps) is variable in direction from grain to grain, which may result from different alteration histories for each grain. These complex magnetization patterns acquired through thermal and chemical alteration history may explain the short wavelength magnetic anomalies observed along our traverse lines. [1] Beinlich, A., Plümper, O., Hövelmann, J., Austrheim, H. and Jamtveit, B. (2012), Terra Nova, in press.
Ground-water resources of the Sevier River basin between Yuba Dam and Leamington Canyon, Utah
Bjorklund, Louis Jay; Robinson, Gerald B.
1968-01-01
The area investigated is a segment of the Sevier River basin, Utah, comprising about 900 square miles and including a 19-mile reach of the Sevier River between Yuba Dam and Leamington Canyon. The larger valleys in the area are southern Juab, Round, and Scipio Valleys. The smaller valleys are Mills, Little, Dog, and Tinctic Wash Valleys.The geology of parts of Scipio, Little, and Mills Valleys and parts of the surrounding highlands was mapped and studied to explain the occurrence of numerous sinkholes in the thre valleys and to show their relation to the large springs in Mills Valley. The sinkholes, which are formed in the alluvium, are alined along faults, which penetrate both the alluvium and the underlying bedrock, and they have been formed by collapse of solution cavities in the underlying bedrock. The bedrock is mostly sandy limestone beds of the upper part of the North Horn Formation and of the Flagstaff Limestone. The numerous faults traversing Scipio Valley in a north-northeasterly direction trend directly toward Molter and Blue Springs in Mills Valley. One fault, which can be traced directly between the springs, probably is the principal channelway for the ground water moving from Scipio and Little Valleys to the springs.
Code of Federal Regulations, 2010 CFR
2010-01-01
... suborbital rocket to the effects of altitude, velocity, acceleration, or burn duration that exceed a level or... area, that a reusable suborbital rocket's instantaneous impact point may not traverse. Key flight... permitted flights may take place. Permitted vehicle means a reusable suborbital rocket operated by a launch...
Code of Federal Regulations, 2012 CFR
2012-01-01
... suborbital rocket to the effects of altitude, velocity, acceleration, or burn duration that exceed a level or... area, that a reusable suborbital rocket's instantaneous impact point may not traverse. Key flight... permitted flights may take place. Permitted vehicle means a reusable suborbital rocket operated by a launch...
Code of Federal Regulations, 2014 CFR
2014-01-01
... suborbital rocket to the effects of altitude, velocity, acceleration, or burn duration that exceed a level or... area, that a reusable suborbital rocket's instantaneous impact point may not traverse. Key flight... permitted flights may take place. Permitted vehicle means a reusable suborbital rocket operated by a launch...
Code of Federal Regulations, 2013 CFR
2013-01-01
... suborbital rocket to the effects of altitude, velocity, acceleration, or burn duration that exceed a level or... area, that a reusable suborbital rocket's instantaneous impact point may not traverse. Key flight... permitted flights may take place. Permitted vehicle means a reusable suborbital rocket operated by a launch...
Code of Federal Regulations, 2011 CFR
2011-01-01
... suborbital rocket to the effects of altitude, velocity, acceleration, or burn duration that exceed a level or... area, that a reusable suborbital rocket's instantaneous impact point may not traverse. Key flight... permitted flights may take place. Permitted vehicle means a reusable suborbital rocket operated by a launch...
Methods for multi-material stereolithography
Wicker, Ryan [El Paso, TX; Medina, Francisco [El Paso, TX; Elkins, Christopher [Redwood City, CA
2011-06-14
Methods and systems of stereolithography for building cost-efficient and time-saving multi-material, multi-functional and multi-colored prototypes, models and devices configured for intermediate washing and curing/drying is disclosed including: laser(s), liquid and/or platform level sensing system(s), controllable optical system(s), moveable platform(s), elevator platform(s), recoating system(s) and at least one polymer retaining receptacle. Multiple polymer retaining receptacles may be arranged in a moveable apparatus, wherein each receptacle is adapted to actively/passively maintain a uniform, desired level of polymer by including a recoating device and a material fill/remove system. The platform is movably accessible to the polymer retaining receptacle(s), elevator mechanism(s) and washing and curing/drying area(s) which may be housed in a shielded enclosure(s). The elevator mechanism is configured to vertically traverse and rotate the platform, thus providing angled building, washing and curing/drying capabilities. A horizontal traversing mechanism may be included to facilitate manufacturing between components of SL cabinet(s) and/or alternative manufacturing technologies.
NASA Astrophysics Data System (ADS)
Silver, M.; Törmä, M.; Silver, K.; Okkonen, J.; Nuñez, M.
2015-08-01
The present paper concentrates on the use of remote sensing by satellite imagery for detecting ancient tracks and roads in the area between Palmyra and the Euphrates in Syria. The Syrian desert was traversed by caravans already in the Bronze Age, and during the Greco-Roman period the traffic increased with the Silk Road and trade as well as with military missions annexing the areas into empires. SYGIS - the Finnish archaeological survey and mapping project traced, recorded and documented ancient sites and roads in the region of Jebel Bishri in Central Syria in 2000-2010 before the outbreak of the civil war in Syria. Captured data of ancient roads and bridge points bring new light to the study of ancient communication framework in the area. Archaeological research carried out by the project on the ground confirmed the authenticity of many road alignments, new military and water harvesting sites as well as civilian settlements, showing that the desert-steppe area was actively used and developed probably from the second century AD. The studies further demonstrated that the area between Palmyra and the Euphrates was militarily more organised already in the second and third centuries AD than earlier believed. Chronologically, the start of this coincided with the "golden age" of the Palmyrene caravans in the second century AD. Topography and landscape were integral parts of the construction of graves/tumuli as sign-posts guiding in the desert, as well as roads and all kinds of settlements whether military or civilian.
NASA Technical Reports Server (NTRS)
Elfes, Alberto; Hall, Jeffery L.; Kulczycki, Eric A.; Cameron, Jonathan M.; Morfopoulos, Arin C.; Clouse, Daniel S.; Montgomery, James F.; Ansar, Adnan I.; Machuzak, Richard J.
2009-01-01
An architecture for autonomous operation of an aerobot (i.e., a robotic blimp) to be used in scientific exploration of planets and moons in the Solar system with an atmosphere (such as Titan and Venus) is undergoing development. This architecture is also applicable to autonomous airships that could be flown in the terrestrial atmosphere for scientific exploration, military reconnaissance and surveillance, and as radio-communication relay stations in disaster areas. The architecture was conceived to satisfy requirements to perform the following functions: a) Vehicle safing, that is, ensuring the integrity of the aerobot during its entire mission, including during extended communication blackouts. b) Accurate and robust autonomous flight control during operation in diverse modes, including launch, deployment of scientific instruments, long traverses, hovering or station-keeping, and maneuvers for touch-and-go surface sampling. c) Mapping and self-localization in the absence of a global positioning system. d) Advanced recognition of hazards and targets in conjunction with tracking of, and visual servoing toward, targets, all to enable the aerobot to detect and avoid atmospheric and topographic hazards and to identify, home in on, and hover over predefined terrain features or other targets of scientific interest. The architecture is an integrated combination of systems for accurate and robust vehicle and flight trajectory control; estimation of the state of the aerobot; perception-based detection and avoidance of hazards; monitoring of the integrity and functionality ("health") of the aerobot; reflexive safing actions; multi-modal localization and mapping; autonomous planning and execution of scientific observations; and long-range planning and monitoring of the mission of the aerobot. The prototype JPL aerobot (see figure) has been tested extensively in various areas in the California Mojave desert.
1978-09-01
classified as wet meadow. k. Tame Grassland Community (limited) - This community is of minor extent and importance in the vicinity of Lake Traverse...purposes of flood control and water conservation, the Lake Traverse-lois de Sioux flood control project began operation in 1941. It con- sists of two...reservoir pools--Lake Traverse and Mud Lake--plus 24 miles of channel improvement. Several consepts are recoiended for future development of the
NASA Astrophysics Data System (ADS)
Magnuson, Brian
A proof-of-concept software-in-the-loop study is performed to assess the accuracy of predicted net and charge-gaining energy consumption for potential effective use in optimizing powertrain management of hybrid vehicles. With promising results of improving fuel efficiency of a thermostatic control strategy for a series, plug-ing, hybrid-electric vehicle by 8.24%, the route and speed prediction machine learning algorithms are redesigned and implemented for real- world testing in a stand-alone C++ code-base to ingest map data, learn and predict driver habits, and store driver data for fast startup and shutdown of the controller or computer used to execute the compiled algorithm. Speed prediction is performed using a multi-layer, multi-input, multi- output neural network using feed-forward prediction and gradient descent through back- propagation training. Route prediction utilizes a Hidden Markov Model with a recurrent forward algorithm for prediction and multi-dimensional hash maps to store state and state distribution constraining associations between atomic road segments and end destinations. Predicted energy is calculated using the predicted time-series speed and elevation profile over the predicted route and the road-load equation. Testing of the code-base is performed over a known road network spanning 24x35 blocks on the south hill of Spokane, Washington. A large set of training routes are traversed once to add randomness to the route prediction algorithm, and a subset of the training routes, testing routes, are traversed to assess the accuracy of the net and charge-gaining predicted energy consumption. Each test route is traveled a random number of times with varying speed conditions from traffic and pedestrians to add randomness to speed prediction. Prediction data is stored and analyzed in a post process Matlab script. The aggregated results and analysis of all traversals of all test routes reflect the performance of the Driver Prediction algorithm. The error of average energy gained through charge-gaining events is 31.3% and the error of average net energy consumed is 27.3%. The average delta and average standard deviation of the delta of predicted energy gained through charge-gaining events is 0.639 and 0.601 Wh respectively for individual time-series calculations. Similarly, the average delta and average standard deviation of the delta of the predicted net energy consumed is 0.567 and 0.580 Wh respectively for individual time-series calculations. The average delta and standard deviation of the delta of the predicted speed is 1.60 and 1.15 respectively also for the individual time-series measurements. The percentage of accuracy of route prediction is 91%. Overall, test routes are traversed 151 times for a total test distance of 276.4 km.
NASA Astrophysics Data System (ADS)
Parker, T. J.; Calef, F. J., III; Deen, R. G.; Gengl, H.
2016-12-01
The traverse maps produced tactically for the MER and MSL rover missions are the first step in placing the observations made by each vehicle into a local and regional geologic context. For the MER, Phoenix and MSL missions, 25cm/pixel HiRISE data is available for accurately localizing the vehicles. Viking and Mars Pathfinder, however, relied on Viking Orbiter images of several tens of m/pixel to triangulate to horizon features visible both from the ground and from orbit. After Pathfinder, MGS MOC images became available for these landing sites, enabling much better correlations to horizon features and localization predictions to be made, that were then corroborated with HiRISE images beginning 9 years ago. By combining topography data from MGS, Mars Express, and stereo processing of MRO CTX and HiRISE images into orthomosaics (ORRs) and digital elevation models (DEMs), it is possible to localize all the landers and rover positions to an accuracy of a few tens of meters with respect to the Mars global control net, and to better than half a meter with respect to other features within a HiRISE orthomosaic. JPL's MIPL produces point clouds of the MER Navcam stereo images that can be processed into 1cm/pixel ORR/DEMs that are then georeferenced to a HiRISE/CTX base map and DEM. This allows compilation of seamless mosaics of the lander and rover camera-based ORR/DEMs with the HiRISE ORR/DEM that can be viewed in 3 dimensions with GIS programs with that capability. We are re-processing the Viking Lander, Mars Pathfinder, and Phoenix lander data to allow similar ORR/DEM products to be made for those missions. For the fixed landers and Spirit, we will compile merged surface/CTX/HiRISE ORR/DEMs, that will enable accurate local and regional mapping of these landing sites, and allow comparisons of the results from these missions to be made with current and future surface missions.
Shin, Hae Jin; Moon, Hee Seok; Kang, Sun Hyung; Sung, Jae Kyu; Jeong, Hyun Yong; Kim, Seok Hyun; Lee, Byung Seok; Kim, Ju Seok; Yun, Gee Young
2017-12-01
The purpose of this study was to evaluate the prognostic impact of endoscopic traversability in patients with locally advanced esophageal squamous cell carcinoma.This retrospective study was based on medical records from a single tertiary medical center. The records of 317 patients with esophageal squamous cell carcinoma treated with surgery or definitive chemoradiotherapy (CRT) between January 2009 and March 2016 were reviewed. Finally, we retrieved the data on 168 consecutive patients. These 168 patients were divided into 2 groups based on their endoscopic traversability findings: Group A (the endoscope traversable group), and Group B (the endoscope non-traversable group). We then retrospectively compared the clinical characteristics of these 2 groups.The endoscope non-traversable group (Group B) revealed an advanced clinical stage, a poor Eastern Cooperative Oncology Group (ECOG) score, a lower serum albumin level, a higher rate of requirement for esophageal stent insertion and definitive CRT as initial treatment than the endoscope traversable group (Group A). Patients with endoscope traversable cancer showed a significantly higher 3-year overall survival and 3-year relapse-free survival than patients who were endoscope non-traversable (53.8% vs 17.3%, P < .001 and 71.1% vs 45.3%, P = .003, respectively). Upon multivariate analysis of patients with locally advanced esophageal squamous cell carcinoma treated with definitive CRT, the serum albumin level <3.5 g/dL and endoscopic non-traversability were significant negative factors of survival.Endoscopic traversability in patients with locally advanced esophageal squamous cell carcinoma treated with definitive CRT is a significant prognostic factor. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.
Ronald E. McRoberts; Gregory A. Reams; Paul C. Van Deusen; John W. Moser
2003-01-01
Documents contributions to forest inventory in the areas of sampling, remote sensing, modeling, information management, and analysis with emphasis on implementation of the annual inventory system of the Forest Inventory and Analysis program of the USDA Forest Service.
NASA Astrophysics Data System (ADS)
Nelson, A. R.; Bradley, L.; Personius, S. F.; Johnson, S. Y.
2010-12-01
Deciphering the earthquake histories of faults over the past few thousands of years in tectonically complex forearc regions relies on detailed site-specific as well as regional geologic maps. Here we present examples of site-specific USGS maps used to reconstruct earthquake histories for faults in the Puget Lowland. Near-surface faults and folds in the Puget Lowland accommodate 4-7 mm/yr of north-south shortening resulting from northward migration of forearc blocks along the Cascadia convergent margin. The shortening has produced east-trending uplifts, basins, and associated reverse faults that traverse urban areas. Near the eastern and northern flanks of the Olympic Mountains, complex interactions between north-south shortening and mountain uplift are reflected by normal, oblique-slip, and reverse surface faults. Holocene oblique-slip movement has also been mapped on Whidbey Island and on faults in the foothills of the Cascade Mountains in the northeastern lowland. The close proximity of lowland faults to urban areas may pose a greater earthquake hazard there than do much longer but more distant plate-boundary faults. LiDAR imagery of the densely forested lowland flown over the past 12 years revealed many previously unknown 0.5-m to 6-m-high scarps showing Holocene movement on upper-plate faults. This imagery uses two-way traveltimes of laser light pulses to detect as little as 0.2 m of relative relief on the forest floor. The returns of laser pulses with the longest travel times yield digital elevation models of the ground surface, which we vertically exaggerate and digitally shade from multiple directions at variable transparencies to enhance identification of scarps. Our maps include imagery at scales of 1:40,000 to 1:2500 with contour spacings of 100 m to 0.5 m. Maps of the vertical walls of fault-scarp trenches show complex stratigraphies and structural relations used to decipher the histories of large surface-rupturing earthquakes. These logs (field mapping at 1:8 to 1:20 scales) of 25 trenches are included in five published (and one in preparation) maps along with lithologic descriptions of stratigraphic units and tables of 14C, structural, and stratigraphic data. Maps include soil profile data, topographic profiles across scarps, structural orientation data, or photographs of trench sites or trench walls. Stratigraphy and 14C ages suggest that earthquake recurrence varies from less than a century to many thousands of years. Interpretation and synthesis of such data are reserved for journal papers, which commonly cannot accommodate the detailed, large-format information shown on the maps. Many thanks to Brian Sherrod, Harvey Kelsey, Jason Buck, Ray Wells, Liz Schermer, Rob Witter, Rich Koehler, Rich Briggs, Robert Bogar, Gary Henley, Dave Harding, Koji Okumura, Silvio Pezzopane, Bob Bucknam, Zeb Maharrey, Bill Laprade, Ralph Haugerud, Lee Liberty, Michael Polenz, Eliza Nemser, Trenton Cladouhos, and many others for days to many weeks of effort in our trenches over the past 12 years.
Thompson, Ryan F.
2001-01-01
In 1994, the U.S. Geological Survey, in cooperation with the Sisseton-Wahpeton Sioux Tribe; Roberts County; and the South Dakota Department of Environment and Natural Resources, Geological Survey Program, began a 6-year investigation to describe and quantify the water resources of the area within the 1867 boundary of the Lake Traverse Reservation and adjacent parts of Roberts County. Roberts County is located in extreme northeastern South Dakota, and the 1867 boundary of the Lake Traverse Reservation encompasses much of Roberts County and parts of Marshall, Day, Codington, and Grant Counties in South Dakota and parts of Richland and Sargent Counties in southeast North Dakota. This report includes descriptions of the quantity, quality, and availability of surface and ground water, the extent of the major glacial and bedrock aquifers and named outwash groups, and surface- and ground-water uses within the 1867 boundary of the Lake Traverse Reservation and adjacent parts of Roberts County. The surface-water resources within the 1867 boundary of the Lake Traverse Reservation and adjacent parts of Roberts County include rivers, streams, lakes, and wetlands. The Wild Rice and Bois de Sioux Rivers are tributaries of the Red River within the Souris-Red-Rainy River Basin; the Little Minnesota, Jorgenson, and North Fork Whetstone Rivers are tributaries of the Minnesota River within the Upper Mississippi River Basin, and the James and Big Sioux Rivers are tributaries within the Missouri River Basin. Several of the larger lakes within the study area have been developed for recreation, while many of the smaller lakes and wetlands are used for livestock watering or as wildlife production areas. Statistical summaries are presented for the water-quality data of six selected streams within the study area, and the dominant chemical species are listed for 17 selected lakes within the study area. The glacial history of the study area has led to a rather complex system of glacial aquifers. The boundaries of 11 aquifers and 6 named outwash groups were delineated based on hydrogeologic cross sections, water levels, and water-quality similarities/dissimilarities. The glacial aquifers include Coteau Lakes system, Big Sioux, Alta-mont, Revillo, James, Veblen system, Spiritwood, Hankinson, Rosholt, Milnor Channel, and Fairmount; the bedrock aquifer included in this report is the Dakota. Named outwash groups include the Prairie Coteau, Lonesome Lake, Marday, Eden, Roslyn, and Wilmot. A summary of the character-istics of each of the major aquifers and outwash groups and a summary of selected chemical analyses for each aquifer and outwash group are presented. All aquifers and outwash groups in the study area have either moderately hard or very hard water and are considered fresh to slightly saline. One or more water samples from some of the aquifers and outwash groups have a constituent that was above the recommended or mandatory limit for drinking water. Most aquifers and outwash groups have dissolved solids and sulfate contents above the recommended levels of 500 and 250 mg/L (milligrams per liter), respectively. The Dakota aquifer was the only one to have a mean chloride concentration above the recommended level of 250 mg/L. Nitrate concentrations greater than the mandatory limit of 10 mg/L were found in the Big Sioux aquifer and the Coteau Lakes and Veblen aquifer systems. Concentrations of arsenic greater than 10 ?g/L (micrograms per liter) were found in the Coteau Lakes and Veblen aquifer systems, and in the Rosholt and Fairmount aquifers. Municipalities and rural water systems currently provide most of the water used in the study area-nearly all of it from ground-water sources. Surface-water use is limited to livestock watering. About 55 percent of the total water used in Roberts County is for domestic purposes, with most domestic users served by a public supply system. Irrigation accounts for about 10 percent of the total water used. All
Soil gas studies along the Trans-Challis fault system near Idaho City, Boise County, Idaho
McCarthy, J.H.; Kiilsgaard, T.H.
2001-01-01
Soil gases were sampled along several traverses that cross the Trans-Challis fault system in central Idaho. Anomalous carbon dioxide, hydrogen, oxygen, hydrocarbon, and sulfur gas concentrations coincide with faults and known mineralized areas. Anomalies in areas not known to be mineralized may reflect undiscovered mineral deposits or concealed faults. Soil gases may be a useful exploration guide for mineral deposits in this terrane.
Terrain, weather pose challenges in Minnesota project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trojack, L.
1994-12-01
This paper briefly reviews an innovative method used in installing a natural gas pipeline in Minnesota which traversed a marsh area. Because of the special problems associated with this wetland area, special equipment and techniques had to be used to minimize disturbance associated with the construction. It describes the equipment and the resulting performance the equipment had. It proved to significantly reduce disturbance and result in minimum site restoration work.
Interpreting Radar View near Mars' South Pole, Orbit 1360
NASA Technical Reports Server (NTRS)
2006-01-01
A radargram from the Shallow Subsurface Radar instrument (SHARAD) on NASA's Mars Reconnaissance Orbiter is shown in the upper-right panel and reveals detailed structure in the polar layered deposits of the south pole of Mars. The sounding radar collected the data presented here during orbit 1360 of the mission, on Nov. 10, 2006. The horizontal scale in the radargram is distance along the ground track. It can be referenced to the ground track map shown in the lower right. The radar traversed from about 74 degrees to 85 degrees south latitude, or about 650 kilometers (400 miles). The ground track map shows elevation measured by the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor orbiter. Green indicates low elevation; reddish-white indicates higher elevation. The traverse proceeds up onto a plateau formed by the layers. The vertical scale on the radargram is time delay of the radar signals reflected back to Mars Reconnaissance Orbiter from the surface and subsurface. For reference, using an assumed velocity of the radar waves in the subsurface, time is converted to depth below the surface at one place: about 800 meters (2,600 feet) to one of the strongest subsurface reflectors. This reflector marks the base of the polar layered deposits. The color scale varies from black for weak reflections to white for strong reflections. The middle panel shows mapping of the major subsurface reflectors, some of which can be traced for a distance of 100 kilometers (60 miles) or more. The layering manifests the recent climate history of Mars, recorded by the deposition and removal of ice and dust. The Shallow Subsurface Radar was provided by the Italian Space Agency (ASI). Its operations are led by the University of Rome and its data are analyzed by a joint U.S.-Italian science team. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter for the NASA Science Mission Directorate, Washington.NASA Technical Reports Server (NTRS)
Weaver, Johnathan M.
1993-01-01
A method was developed to plan feasible and obstacle-avoiding paths for two spatial robots working cooperatively in a known static environment. Cooperating spatial robots as referred to herein are robots which work in 6D task space while simultaneously grasping and manipulating a common, rigid payload. The approach is configuration space (c-space) based and performs selective rather than exhaustive c-space mapping. No expensive precomputations are required. A novel, divide-and-conquer type of heuristic is used to guide the selective mapping process. The heuristic does not involve any robot, environment, or task specific assumptions. A technique was also developed which enables solution of the cooperating redundant robot path planning problem without requiring the use of inverse kinematics for a redundant robot. The path planning strategy involves first attempting to traverse along the configuration space vector from the start point towards the goal point. If an unsafe region is encountered, an intermediate via point is identified by conducting a systematic search in the hyperplane orthogonal to and bisecting the unsafe region of the vector. This process is repeatedly applied until a solution to the global path planning problem is obtained. The basic concept behind this strategy is that better local decisions at the beginning of the trouble region may be made if a possible way around the 'center' of the trouble region is known. Thus, rather than attempting paths which look promising locally (at the beginning of a trouble region) but which may not yield overall results, the heuristic attempts local strategies that appear promising for circumventing the unsafe region.
Context of ancient aqueous environments on Mars from in situ geologic mapping at Endeavour Crater
Crumpler, L.S.; Arvidson, R. E.; Bell, J.; Clark, B. C.; Cohen, B. A.; Farrand, W. H.; Gellert, Ralf; Golombek, M.; Grant, J. A.; Guinness, E.; Herkenhoff, Kenneth E.; Johnson, J. R.; Jolliff, B.; Ming, D. W.; Mittlefehldt, D. W.; Parker, T.; Rice, J. W.; Squyres, S. W.; Sullivan, R.; Yen, A. S.
2015-01-01
Using the Mars Exploration Rover Opportunity, we have compiled one of the first field geologic maps on Mars while traversing the Noachian terrain along the rim of the 22 km diameter Endeavour Crater (Latitude −2°16′33″, Longitude −5°10′51″). In situ mapping of the petrographic, elemental, structural, and stratigraphic characteristics of outcrops and rocks distinguishes four mappable bedrock lithologic units. Three of these rock units predate the surrounding Burns formation sulfate-rich sandstones and one, the Matijevic Formation, represents conditions on early Mars predating the formation of Endeavour Crater. The stratigraphy assembled from these observations includes several geologic unconformities. The differences in lithologic units across these unconformities record changes in the character and intensity of the Martian aqueous environment over geologic time. Water circulated through fractures in the oldest rocks over periods long enough that texturally and elementally significant alteration occurred in fracture walls. These oldest pre-Endeavour rocks and their network of mineralized and altered fractures were preserved by burial beneath impact ejecta and were subsequently exhumed and exposed. The alteration along joints in the oldest rocks and the mineralized veins and concentrations of trace metals in overlying lithologic units is direct evidence that copious volumes of mineralized and/or hydrothermal fluids circulated through the early Martian crust. The wide range in intensity of structural and chemical modification from outcrop to outcrop along the crater rim shows that the ejecta of large (>8 km in diameter) impact craters is complex. These results imply that geologic complexity is to be anticipated in other areas of Mars where cratering has been a fundamental process in the local and regional geology and mineralogy.
NASA Astrophysics Data System (ADS)
Kumar, S.; Kulloli, R. N.; Tewari, J. C.; Singh, J. P.; Singh, A.
2014-11-01
Ceropegia bulbosa Roxb. is a narrow endemic, tuberous twiner of Asclepiadaceae family. It is medicinally important: tubers are nutritive and edible, leaves are digestive and a cure for dysentery and diarrhea. Exploitation for its tubers and poor regeneration of this species has shrunk its distribution. In order to know its present status, we report here the results of its appraisal in Rajasthan, using remote sensing and ground truthing in the past five years (2009-14). A base map of C. bulbosa was prepared using Geographical Information System (GIS), open source software Quantum GIS, SAGA. The Landsat Enhanced Thematic Mapper (ETM) +Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Global Digital Elevation Model (GDEM) Satellite Data were used in this study. ASTER and GDEM Data was clipped with district boundary and provided color range to get elevation information. A digital elevation model of Rajasthan physiography was developed from ASTER GDEM of 30-m resolution. GIS layers of Area of occurrences for C. bulbosa plant and elevation were created. This map along with topographic sheets of 1:50000 were used for field traversing and ground truthing as per GPS location inferred from map. Its geographic distribution was assessed using MaxEnt distribution modelling algorithm that employed 12 presence locality data, 19 bioclimatic variables, and elevation data. Results of this modelling predicted occurrence of C. bulbosa in the districts of Sirohi, Jalore, Barmer, Pali, Ajmer, Jhalawar, Dungarpur, Banswara, Baran, Kota, Bundi and Chittorgarh. Ground validation in these districts revealed its presence only at four places in three districts confirming its rarity. Analysis of dominance at their sites of occurrence revealed their poor populations and sub dominant status (RIV = 20-32) and very low density (2-12 plants per tenth ha).
Velocity profile development for a poultry facility acid scrubber
USDA-ARS?s Scientific Manuscript database
Determination of the air velocity profile for 12 experimental configurations (ECs) of an acid scrubber was carried out using an equal area traverse method with a vane axial anemometer. Four velocity profile plots were created for each configuration to determine the four optimal ECs. ECs were selecte...
36 CFR 28.23 - Certificates of suspension of authority for acquisition by condemnation.
Code of Federal Regulations, 2010 CFR
2010-07-01
... developed area on the ground level; (2) On the survey, the line of mean high water, the toe of the dune, and the crest of the dune shall be identified if they traverse the lot; (3) A floor plan of each floor of...
Into the Deep: Mindful Music Learning
ERIC Educational Resources Information Center
Lind, Vicki R.
2014-01-01
This article outlines strategies for using thinking routines in the general music classroom to foster deeper learning. Based on the Artful Thinking program, a model developed by Harvard's Project Zero in collaboration with Traverse City [Michigan] Area Public Schools, thinking routines were developed to draw students into a more meaningful…
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-01
...-AA00 Safety Zones; National Cherry Festival Air Show and Fireworks Display; West Grand Traverse Bay... National Cherry Festival in Traverse City, MI will host an air show over the West Arm of Grand Traverse Bay. At the conclusion of the National Cherry Festival on July 6, 2013, fireworks will be launched in...
NNSS Soils Monitoring: Plutonium Valley (CAU366) FY2012
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, Julianne J.; Mizell, Steve A.; Nikolich, George
2013-01-01
The U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA), Nevada Site Office (NSO), Environmental Restoration Soils Activity has authorized the Desert Research Institute (DRI) to conduct field assessments of potential sediment transport of contaminated soil from Corrective Action Unit (CAU) 366, Area 11 Plutonium Valley Dispersion Sites Contamination Area (CA) during precipitation runoff events. Field measurements at the T-4 Atmospheric Test Site (CAU 370) suggest that radionuclide-contaminated soils may have migrated along a shallow ephemeral drainage that traverses the site (NNSA/NSO, 2009). (It is not entirely clear how contaminated soils got into their present location at the T-4more » Site, but flow to the channel has been redirected and the contamination does not appear to be migrating at present.) Aerial surveys in selected portions of the Nevada National Security Site (NNSS) also suggest that radionuclide-contaminated soils may be migrating along ephemeral channels in Areas 3, 8, 11, 18, and 25 (Colton, 1999). In Area 11, several low-level airborne surveys of the Plutonium Valley Dispersion Sites (CAU 366) show plumes of Americium 241 (Am-241) extending along ephemeral channels (Figure 1, marker numbers 5 and 6) below Corrective Action Site (CAS) 11-23-03 (marker number 3) and CAS 11 23-04 (marker number 4) (Colton, 1999). Plutonium Valley in Area 11 of the NNSS was selected for the study because of the aerial survey evidence suggesting downstream transport of radionuclide-contaminated soil. The aerial survey (Figure 1) shows a well defined finger of elevated radioactivity (marker number 5) extending to the southwest from the southernmost detonation site (marker number 4). This finger of contamination overlies a drainage channel mapped on the topographic base map used for presentation of the survey data suggesting surface runoff as a likely cause of the contaminated area. Additionally, instrumenting sites strongly suspected of conveying soil from areas of surface contamination offers the most efficient means to confirm that surface runoff may transport radioactive contamination as a result of ambient precipitation/runoff events. Closure plans being developed for the CAUs on the NNSS may include post-closure monitoring for possible release of radioactive contaminants. Determining the potential for transport of radionuclide-contaminated soils under ambient meteorological conditions will facilitate an appropriate closure design and post-closure monitoring program.« less
Lidz, B.H.; Brock, J.C.; Nagle, D.B.
2008-01-01
A recently developed remote-sensing instrument acquires high-quality digital photographs in shallow-marine settings within water depths of 15 m. The technology, known as the Along-Track Reef-Imaging System, provides remarkably clear, georeferenced imagery that allows visual interpretation of benthic class (substrates, organisms) for mapping coral reef habitats, as intended. Unforeseen, however, are functions new to the initial technologic purpose: interpr??table evidence for real-time biogeologic processes and for perception of scaled-up skeletal self-similarity of scleractinian microstructure. Florida reef sea trials lacked the grid structure required to map contiguous habitat and submarine topography. Thus, only general observations could be made relative to times and sites of imagery. Degradation of corals was nearly universal; absence of reef fish was profound. However, ???1% of more than 23,600 sea-trial images examined provided visual evidence for local environs and processes. Clarity in many images was so exceptional that small tracks left by organisms traversing fine-grained carbonate sand were visible. Other images revealed a compelling sense, not yet fully understood, of the microscopic wall structure characteristic of scleractinian corals. Conclusions drawn from classifiable images are that demersal marine animals, where imaged, are oblivious to the equipment and that the technology has strong capabilities beyond mapping habitat. Imagery acquired along predetermined transects that cross a variety of geomorphic features within depth limits will ( 1) facilitate construction of accurate contour maps of habitat and bathymetry without need for ground-truthing, (2) contain a strong geologic component of interpreted real-time processes as they relate to imaged topography and regional geomorphology, and (3) allow cost-effective monitoring of regional- and local-scale changes in an ecosystem by use of existing-image global-positioning system coordinates to re-image areas. Details revealed in the modern setting have taphonomic implications for what is often found in the geologic record.
NASA Astrophysics Data System (ADS)
Susanti, Hesty; Suprijanto, Kurniadi, Deddy
2018-02-01
Needle visibility in ultrasound-guided technique has been a crucial factor for successful interventional procedure. It has been affected by several factors, i.e. puncture depth, insertion angle, needle size and material, and imaging technology. The influences of those factors made the needle not always well visible. 20 G needles of 15 cm length (Nano Line, facet) were inserted into water bath with variation of insertion angles and depths. Ultrasound measurements are performed with BK-Medical Flex Focus 800 using 12 MHz linear array and 5 MHz curved array in Ultrasound Guided Regional Anesthesia mode. We propose 3 criteria to evaluate needle visibility, i.e. maximum intensity, mean intensity, and the ratio between minimum and maximum intensity. Those criteria were then depicted into representative maps for practical purpose. The best criterion candidate for representing the needle visibility was criterion 1. Generally, the appearance pattern of the needle from this criterion was relatively consistent, i.e. for linear array, it was relatively poor visibility in the middle part of the shaft, while for curved array, it is relatively better visible toward the end of the shaft. With further investigations, for example with the use of tissue-mimicking phantom, the representative maps can be built for future practical purpose, i.e. as a tool for clinicians to ensure better needle placement in clinical application. It will help them to avoid the "dead" area where the needle is not well visible, so it can reduce the risks of vital structures traversing and the number of required insertion, resulting in less patient morbidity. Those simple criteria and representative maps can be utilized to evaluate general visibility patterns of the needle in vast range of needle types and sizes in different insertion media. This information is also important as an early investigation for future research of needle visibility improvement, i.e. the development of beamforming strategies and ultrasound enhanced (echogenic) needle.
Geologic map of the Murray Quadrangle, Newton County, Arkansas
Hudson, Mark R.; Turner, Kenzie J.
2016-07-06
This map summarizes the geology of the Murray quadrangle in the Ozark Plateaus region of northern Arkansas. Geologically, the area is on the southern flank of the Ozark dome, an uplift that has the oldest rocks exposed at its center, in Missouri. Physiographically, the Murray quadrangle is within the Boston Mountains, a high plateau region underlain by Pennsylvanian sandstones and shales. Valleys of the Buffalo River and Little Buffalo River and their tributaries expose an approximately 1,600-ft-thick (488-meter-thick) sequence of Ordovician, Mississippian, and Pennsylvanian carbonate and clastic sedimentary rocks that have been mildly deformed by a series of faults and folds. The Buffalo National River, a park that encompasses the Buffalo River and adjacent land that is administered by the National Park Service is present at the northwestern edge of the quadrangle.Mapping for this study was carried out by field inspection of numerous sites and was compiled as a 1:24,000 geographic information system (GIS) database. Locations and elevation of sites were determined with the aid of a global positioning satellite receiver and a hand-held barometric altimeter that was frequently recalibrated at points of known elevation. Hill-shade relief and slope maps derived from a U.S. Geological Survey 10-meter digital elevation model as well as orthophotographs were used to help trace ledge-forming units between field traverses within the Upper Mississippian and Pennsylvanian part of the stratigraphic sequence. Strike and dip of beds were typically measured along stream drainages or at well-exposed ledges. Structure contours, constructed on the top of the Boone Formation and the base of a prominent sandstone unit within the Bloyd Formation, were drawn based on the elevations of field sites on these contacts well as other limiting information for their minimum elevations above hilltops or their maximum elevations below valley bottoms.
Li, Chen; Pullin, Andrew O; Haldane, Duncan W; Lam, Han K; Fearing, Ronald S; Full, Robert J
2015-06-22
Many animals, modern aircraft, and underwater vehicles use fusiform, streamlined body shapes that reduce fluid dynamic drag to achieve fast and effective locomotion in air and water. Similarly, numerous small terrestrial animals move through cluttered terrain where three-dimensional, multi-component obstacles like grass, shrubs, vines, and leaf litter also resist motion, but it is unknown whether their body shape plays a major role in traversal. Few ground vehicles or terrestrial robots have used body shape to more effectively traverse environments such as cluttered terrain. Here, we challenged forest-floor-dwelling discoid cockroaches (Blaberus discoidalis) possessing a thin, rounded body to traverse tall, narrowly spaced, vertical, grass-like compliant beams. Animals displayed high traversal performance (79 ± 12% probability and 3.4 ± 0.7 s time). Although we observed diverse obstacle traversal strategies, cockroaches primarily (48 ± 9% probability) used a novel roll maneuver, a form of natural parkour, allowing them to rapidly traverse obstacle gaps narrower than half their body width (2.0 ± 0.5 s traversal time). Reduction of body roundness by addition of artificial shells nearly inhibited roll maneuvers and decreased traversal performance. Inspired by this discovery, we added a thin, rounded exoskeletal shell to a legged robot with a nearly cuboidal body, common to many existing terrestrial robots. Without adding sensory feedback or changing the open-loop control, the rounded shell enabled the robot to traverse beam obstacles with gaps narrower than shell width via body roll. Such terradynamically 'streamlined' shapes can reduce terrain resistance and enhance traversability by assisting effective body reorientation via distributed mechanical feedback. Our findings highlight the need to consider body shape to improve robot mobility in real-world terrain often filled with clutter, and to develop better locomotor-ground contact models to understand interaction with 3D, multi-component terrain.
Erdman, J.A.; Cookro, T.M.; O'Leary, R. M.; Harms, T.F.
1988-01-01
Big sagebrush - a cold-desert species that dominates the terrain over large parts of western United States - was sampled along several traverses that crossed thermally metamorphosed limestone, phyllitic shale, and schist of the Middle and Upper Cambrian Preble Formation that host skarn-, disseminated gold and silver-, and hot springs gold-type mineral occurrences. Patterns of detectable levels of gold (8 to 28 ppb or ng g-1) in ash of new growth were consistent with areas affected by known or suspected gold mineralization. Soils collected along one of the traverses where a selenium-indicator plant was common contained no gold above background levels of 2ppb, but were consistently high in As, Sb, and Zn, and several samples were unusually high in Se (maximum 11 ppm or ??g g-1). Sagebrush along this traverse contained Li at levels above norms for this species. We also found a puzzling geochemical anomaly at a site basinward from active hot springs along a range-front fault scarp. Sagebrush at this site contained a trace of gold and an unusually high concentration of Cd (13 ppm) and the soil had anomalous concentrations of Cd and Bi (3.2 and 6 ppm, respectively). The source of this anomaly could be either metal-rich waters from an irrigation ditch or leakage along a buried fault. Despite the limited nature of the study, we conclude that gold in sagebrush could be a cost-effective guide to drilling locations in areas where the geology seems favorable for disseminated and vein precious metals. ?? 1988.
Effect of Varying Crustal Thickness on CHAMP Geopotential Data
NASA Technical Reports Server (NTRS)
Taylor, P. T.; Kis, K. I.; vonFrese, R. R. B.; Korhonen, J. V.; Wittmann, G.; Kim, H. R.; Potts, L. V.
2003-01-01
To determine the effect of crustal thickness variation on satellite-altitude geopotential anomalies we compared two regions of Europe with vastly different values, Central/Southern Finland and the Pannonian Basin. Crustal thickness exceeds 62 km in Finland and is less than 26 km in the Pannonian Basin. Heat-flow maps indicate that the thinner and more active crust of the Pannonian Basin has a value nearly three times that of the Finnish Svecofennian Province. Ground based gravity mapping in Hungary shows that the free-air gravity anomalies across the Pannonian Basin are near 0 to +20 mGal with shorter wavelength anomalies from +40 to less than +60 mGal and some 0 to greater than -20 mGal. Larger anomalies are detected in the mountainous areas. The minor value anomalies can indicate the isostatic equilibrium for Hungary (the central part of the Pannonian Basin). Gravity data over Finland are complicated by de-glaciation. CHAMP gravity data (400 km) indicates a west-east positive gradient of greater than 4 mGal across Central/Southern Finland and an ovoid positive anomaly (approximately 4 mGal) quasi-coincidental with the magnetic anomaly traversing the Pannonian Basin. CHAMP magnetic data (425 km) reveal elongated semicircular negative anomalies for both regions with South-Central Finland having larger amplitude (less than -6 nT) than that over the Pannonian Basin, Hungary (less than -5 nT). In both regions subducted oceanic lithosphere has been proposed as the anomalous body.
Synergy in spreading processes: from exploitative to explorative foraging strategies.
Pérez-Reche, Francisco J; Ludlam, Jonathan J; Taraskin, Sergei N; Gilligan, Christopher A
2011-05-27
An epidemiological model which incorporates synergistic effects that allow the infectivity and/or susceptibility of hosts to be dependent on the number of infected neighbors is proposed. Constructive synergy induces an exploitative behavior which results in a rapid invasion that infects a large number of hosts. Interfering synergy leads to a slower and sparser explorative foraging strategy that traverses larger distances by infecting fewer hosts. The model can be mapped to a dynamical bond percolation with spatial correlations that affect the mechanism of spread but do not influence the critical behavior of epidemics. © 2011 American Physical Society
NASA Technical Reports Server (NTRS)
Young, Kelsey E.; Evans, C. A.; Hodges, K. V.
2012-01-01
While traditional geologic mapping includes the examination of structural relationships between rock units in the field, more advanced technology now enables us to simultaneously collect and combine analytical datasets with field observations. Information about tectonomagmatic processes can be gleaned from these combined data products. Historically, construction of multi-layered field maps that include sample data has been accomplished serially (first map and collect samples, analyze samples, combine data, and finally, readjust maps and conclusions about geologic history based on combined data sets). New instruments that can be used in the field, such as a handheld xray fluorescence (XRF) unit, are now available. Targeted use of such instruments enables geologists to collect preliminary geochemical data while in the field so that they can optimize scientific data return from each field traverse. Our study tests the application of this technology and projects the benefits gained by real-time geochemical data in the field. The integrated data set produces a richer geologic map and facilitates a stronger contextual picture for field geologists when collecting field observations and samples for future laboratory work. Real-time geochemical data on samples also provide valuable insight regarding sampling decisions by the field geologist
Robust, Flexible Motion Control for the Mars Explorer Rovers
NASA Technical Reports Server (NTRS)
Maimone, Mark; Biesiadecki, Jeffrey
2007-01-01
The Mobility Flight Software, running on computers aboard the Mars Explorer Rover (MER) robotic vehicles Spirit and Opportunity, affords the robustness and flexibility of control to enable safe and effective operation of these vehicles in traversing natural terrain. It can make the vehicles perform specific maneuvers commanded from Earth, and/or can autonomously administer multiple aspects of mobility, including choice of motion, measurement of actual motion, and even selection of targets to be approached. Motion of a vehicle can be commanded by use of multiple layers of control, ranging from motor control at a low level, direct drive operations (e.g., motion along a circular arc, motion along a straight line, or turn in place) at an intermediate level to goal-position driving (that is, driving to a specified location) at a high level. The software can also perform high-level assessment of terrain and selection of safe paths across the terrain: this involves processing of the digital equivalent of a local traversability map generated from images acquired by stereoscopic pairs of cameras aboard the vehicles. Other functions of the software include interacting with the rest of the MER flight software and performing safety checks.
NASA Astrophysics Data System (ADS)
Aizebeokhai, Ahzegbobor P.; Oyeyemi, Kehinde D.
2014-12-01
The use of most conventional electrode configurations in electrical resistivity survey is often time consuming and labour intensive, especially when using manual data acquisition systems. Often, data acquisition teams tend to reduce data density so as to speed up field operation thereby reducing the survey cost; but this could significantly degrade the quality and resolution of the inverse models. In the present work, the potential of using the multiple-gradient array, a non-conventional electrode configuration, for practical cost effective and rapid subsurface resistivity and induced polarization mapping was evaluated. The array was used to conduct 2D resistivity and time-domain induced polarization imaging along two traverses in a study site at Ota, southwestern Nigeria. The subsurface was characterised and the main aquifer delineated using the inverse resistivity and chargeability images obtained. The performance of the multiple-gradient array was evaluated by correlating the 2D resistivity and chargeability images with those of the conventional Wenner array as well as the result of some soundings conducted along the same traverses using Schlumberger array. The multiple-gradient array has been found to have the advantage of measurement logistics and improved image resolution over the Wenner array.
Time for pulse traversal through slabs of dispersive and negative ({epsilon}, {mu}) materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nanda, Lipsa; Ramakrishna, S. Anantha
2007-12-15
The traversal times for an electromagnetic pulse traversing a slab of dispersive and dissipative material with negative dielectric permittivity ({epsilon}) and magnetic permeability ({mu}) have been calculated by using the average flow of electromagnetic energy in the medium. The effects of bandwidth of the pulse and dissipation in the medium have been investigated. While both large bandwidth and large dissipation have similar effects in smoothening out the resonant features that appear due to Fabry-Perot resonances, large dissipation can result in very small or even negative traversal times near the resonant frequencies. We have also investigated the traversal times and Wignermore » delay times for obliquely incident pulses and evanescent pulses. The coupling to slab plasmon-polariton modes in frequency ranges with negative {epsilon} or {mu} is shown to result in large traversal times at the resonant conditions. We also find that the group velocity mainly contributes to the delay times for pulses propagating across a slab with n=-1. We have checked that the traversal times are positive and subluminal for pulses with sufficiently large bandwidths.« less
NASA Technical Reports Server (NTRS)
Skinner, J. A., Jr.; Eppler, D. B.; Bleacher, J. E.; Evans, C. A.; Feng, W.; Gruener, J.; Hurwitz, D. M.; Janoiko, B.; Whitson, P.
2014-01-01
Cartographic products and - specifically - geologic maps provide critical assistance for establishing physical and temporal frameworks of planetary surfaces. The technical methods that result in the creation of geologic maps vary depending on how observations are made as well as the overall intent of the final products [1-3]. These methods tend to follow a common linear work flow, including the identification and delineation of spatially and temporally discrete materials (units), the documentation of their primary (emplacement) and secondary (erosional) characteristics, analysis of the relative and absolute age relationships between these materials, and the collation of observations and interpretations into an objective map product. The "objectivity" of a map is critical cross comparison with overlapping maps and topical studies as well as its relevance to scientific posterity. However, the "accuracy" and "correctness" of a geologic map is very subject to debate. This can be evidenced by comparison of existing geologic maps at various scales, particularly those compiled through field- and remote-based mapped efforts. Our study focuses on comparing the fidelity of (1) "Apollo-style" geologic investigations, where typically non-geologist crew members follow static traverse routes established through pre-mission planning, and (2) "traditional" field-based investigations, where geologists are given free rein to observe without preplanned routes. This abstract summarizes the regional geology wherein our study was conducted, presents the geologic map created from traditional field mapping techniques, and offers basic insights into how geologic maps created from different tactics can be reconciled in support of exploratory missions. Additional abstracts [4-6] from this study discuss various exploration and science results of these efforts.
NASA Astrophysics Data System (ADS)
Hauber, Ernst; Orgel, Csilla; van Gasselt, Stephan; Reiss, Dennis; Johnsson, Andreas; Ramsdale, Jason; Balme, Matthew; Conway, Susan; Costard, Francois; Gallagher, Colman; Kereszturi, Akos; Platz, Thomas; Séjourné, Antoine; Skinner, James; Swirad, Zuzanna; Łosiak, Anna
2015-04-01
An International Space Science Institute (ISSI) team project has been convened to study the northern plains of Mars. It uses a geomorphological grid-mapping approach to compare ice-related landforms across N-S traverses in the three main basins of the northern plains: Acidalia, Arcadia, and Utopia Planitiae. The main science questions are (i) the distribution of ice-related landforms in the northern plains and their relation to distinct latitude bands or different geological units, (ii) the relationship between the latitude dependent mantle (LDM) and landforms indicative of ground ice, and (iii) the distributions and associations of recent landforms indicative of thaw of ice or snow. We mapped individual landforms across the Acidalia Planitia that may have been formed in association with ice or water in an attempt to determine their extent and identify possible spatial relationships and genetic links between them. Our list includes mantling deposits, small-scale polygons, gullies, viscous flow features, thumbprint terrain (TPT), giant polygons and large pitted mounds (LPM). Our resulting maps show the distribution of specific landforms (no data - absence - presence - dominance) in grid cells with a size of ~20 × 20 km, but allows also for some ambiguity (possible). Preliminary results show that the mantling deposits are ubiquitous and occur basically everywhere between ~43°N and almost the margin of the north polar cap. As their surface may appear smooth if intact, their texture can be difficult to detect at CTX scale. Gullies were observed within a limited latitude range between ~32°N and ~54°N. They predominantly occur in Acidalia and Acidalia Colles, although gullies were found in several impact craters. Small-scale polygons occur between ~60°N to ~70°N in agreement with previous studies. They are predominantly oriented in orthogonal networks in crater interiors, depressions and on plains. Viscous flow features are present only in higher-relief areas of the Acidalia Mensae and Colles. Their morphology is not well pronounced, partially subdued and covered, and most features are restricted to debris aprons distributed circumferentially around small knobs. TPT appears north of about 30°N in the most distal parts of the Chryse outflow channels and shows a transition zone with LPM at around 36°N and it is not observed north of ~39N°. The giant polygons with the LPM have been considered analogous to fluid expulsion features in terrestrial sedimentary basins. They characterize the study area from to 35 N° until 61 N° and completely disappear in the Acidalia Colles region. Grid mapping proved to be an efficient way to map small-scale landforms over wide areas. The distribution of possible ice- and water-related features in Acidalia is clearly latitude- and topography-dependent
PROTOZOA IN SUBSURFACE SEDIMENTS FROM SITE CONTAMI- NATED WITH AVIATION GASOLINE OR JET FUEL
Numbers of protozoa in the subsurface of aviation gasoline and jet fuel spill areas at a Coast Guard base at Traverse City, Mich., were determined. Boreholes were drilled in an uncontaminated location, in contaminated but untreated parts of the fuel plumes, and in the aviation ga...
Atmospheric Science Data Center
2013-04-16
article title: Smoke from Asian Fires Traverses the Pacific ... Russia and northeast China, and produced a large amount of smoke that rose to form a thick layer of tiny atmospheric particles, or ... northern portion of the Pacific Ocean, the thickness of the smoke passing over an area south of the Aleutian Islands was measured by the ...
High-Performance Plastic Sled Design for Polar Traversing
2015-06-01
snow resupply traverses in Antarctica and Greenland tow high- efficiency fuel sleds that consist of flexible fuel bladders strapped to flexi- ble sheets...Foundation, Division of Polar Programs (NSF-PLR), operates over-snow traverses in Antarctica and Greenland to resupply their science stations. The 1030...mile (one way) South Pole Traverse (SPoT) begins at McMurdo Station on Ross Island, travels across the Ross Ice Shelf, up the Leverett Glacier, and
Traverse Planning Experiments for Future Planetary Surface Exploration
NASA Technical Reports Server (NTRS)
Hoffman, Stephen J.; Voels, Stephen A.; Mueller, Robert P.; Lee, Pascal C.
2012-01-01
The purpose of the investigation is to evaluate methodology and data requirements for remotely-assisted robotic traverse of extraterrestrial planetary surface to support human exploration program, assess opportunities for in-transit science operations, and validate landing site survey and selection techniques during planetary surface exploration mission analog demonstration at Haughton Crater on Devon Island, Nunavut, Canada. Additionally, 1) identify quality of remote observation data sets (i.e., surface imagery from orbit) required for effective pre-traverse route planning and determine if surface level data (i.e., onboard robotic imagery or other sensor data) is required for a successful traverse, and if additional surface level data can improve traverse efficiency or probability of success (TRPF Experiment). 2) Evaluate feasibility and techniques for conducting opportunistic science investigations during this type of traverse. (OSP Experiment). 3) Assess utility of remotely-assisted robotic vehicle for landing site validation survey. (LSV Experiment).
NASA Astrophysics Data System (ADS)
Behrendt, J. C.
2005-12-01
When 12 countries established scientific stations in Antarctica for the 1957-58 International Geophysical Year (IGY), the Cold War was at its height, seven countries had made claims in Antarctica, and the Antarctic Treaty was a few years in the future. The U.S. program was operated by the Navy and territorial claims were secretly made at several locations during the IGY; these were never officially announced and the U.S. remains a non-claimant state. I was a graduate student geophysicist (assistant seismologist) on the unexplored Filchner-Ronne Ice Shelf as part of the only large scale field project of the U.S. program. Starting in 1956, the U.S. began a series of oversnow traverses making seismic reflection ice soundings (and other geophysical measurements) and glaciological studies to determine the thickness and budget of the Antarctic Ice Sheet. The USSR and France made similar traverses coordinated through the IGY. Although geology and topographic mapping were not part of the IGY program because of the claims issue, and the possibility of mineral resources discoveries, the oversnow traverse parties did geologic work where unknown mountains were discovered. The oversnow traverses continued through 1966, and resulted in an excellent first approximation of the snow surface elevation, ice thickness and bed topography of Antarctica, as well as mean annual temperature of that era and snow accumulation. The vacuum tube dictated the logistics of the oversnow traverse program. Seismic equipment including heavy batteries weighed about 500 kg. Therefore a Sno-Cat tracked vehicle was needed to carry this load. Usually three such vehicles were needed for safety. Because about 3-4 l/km of Sno-Cat fuel was consumed, as much as 120 kg/day of fuel was required. A resupply flight could only carry only about 600 kg/flight (varying greatly as to range and type of aircraft), the major air logistic program of the U.S. IGY program were the three oversnow traverses (other than the resupply of the seven U.S. stations in Antarctica). The Filchner Ice Traverse, on which I participated, encountered many crevasses. Vehicles broke through thin snow bridges and one man fell deep into a crevasse. Fortunately there were no deaths and only one serious injury resulting from crevasse accidents on the U.S. Program. Because of hidden agenda related to the Cold War, U.S. (and possibly Soviet) scientists felt that Antarctic research was a duty rather than a privilege as today. The U.S. air program averaged 3.8 deaths/year from 1955-1961 in contrast to 0.1 death/year since about 1970. At least three U.S. scientists died in the early period of the U.S. program. When, if ever, do the ends justify the means? It is one thing if mature individual researchers, professional technicians, aviators, and others take risks with full awareness of the hazards. But it is quite another thing if relatively naive graduate students and new Ph.D.s looking for adventure, such as my colleagues and I in the 1956-1962 period, are sent into harm's way without knowing specifically what they will face, by ambitious senior researchers pursuing their personal scientific objectives, even though these may be of vital national and international importance. I have worked both sides of this street in the past 50 years.
NASA Technical Reports Server (NTRS)
Coulam, C. M.; Dunnette, W. H.; Wood, E. H.
1970-01-01
Two methods whereby a digital computer may be used to regulate a scintiscanning process are discussed from the viewpoint of computer input-output software. The computer's function, in this case, is to govern the data acquisition and storage, and to display the results to the investigator in a meaningful manner, both during and subsequent to the scanning process. Several methods (such as three-dimensional maps, contour plots, and wall-reflection maps) have been developed by means of which the computer can graphically display the data on-line, for real-time monitoring purposes, during the scanning procedure and subsequently for detailed analysis of the data obtained. A computer-governed method for converting scintiscan data recorded over the dorsal or ventral surfaces of the thorax into fractions of pulmonary blood flow traversing the right and left lungs is presented.
NASA Astrophysics Data System (ADS)
Lawley, Russell; Barron, Mark; Lark, Murray
2015-04-01
At BGS, expert elicitation has been used to evaluate uncertainty of surveyed boundaries in several, common, geological scenarios. As a result, a 'collective' understanding of the issues surrounding each scenario has emerged. The work has provoked wider debate in three key areas: a) what can we do to resolve those scenarios where a 'consensus' of understanding cannot be achieved b) what does it mean for survey practices and subsequent use of maps in 3D models c) how do we communicate the 'collective' understanding of geological mapping (with or without consensus for specific scenarios). Previous work elicited expert judgement for uncertainty in six contrasting mapping scenarios. In five cases it was possible to arrive at a consensus model; in a sixth case experts with different experience (length of service, academic background) took very different views of the nature of the mapping problem. The scenario concerned identification of the boundary between two contrasting tills (one derived from Triassic source materials being red in colour; the other, derived from Jurassic materials being grey in colour). Initial debate during the elicitation identified that the colour contrast should provide some degree of confidence in locating the boundary via traditional auger-traverse survey methods. However, as the elicitation progressed, it became clear that the complexities of the relationship between the two Tills were not uniformly understood across the experts and the panel could not agree a consensus regarding the spatial uncertainty of the boundary. The elicitation process allowed a significant degree of structured knowledge-exchange between experts of differing backgrounds and was successful in identifying a measure of uncertainty for what was considered a contentious scenario. However, the findings have significant implications for a boundary-scenario that is widely mapped across the central regions of Great Britain. We will discuss our experience of the use of elicitation methodology and the implications of our results for further work at the BGS to quantify uncertainty in 2d and 3d products. In particular we will consider the impacts of surveyor 'experience' in how the elicitation process works.
The Lunar Mapping and Modeling Project
NASA Astrophysics Data System (ADS)
Noble, S. K.; Nall, M. E.; French, R. A.; Muery, K. G.
2009-12-01
The Lunar Mapping and Modeling Project (LMMP) has been created to manage the development of a suite of lunar mapping and modeling products that support the Constellation Program (CxP) and other lunar exploration activities, including the planning, design, development, test and operations associated with lunar sortie missions, crewed and robotic operations on the surface, and the establishment of a lunar outpost. The information provided through LMMP will assist CxP in: planning tasks in the areas of landing site evaluation and selection, design and placement of landers and other stationary assets, design of rovers and other mobile assets, developing terrain-relative navigation (TRN) capabilities, and assessment and planning of science traverses. The project draws on expertise from several NASA and non-NASA organizations (MSFC, ARC, GSFC, JPL, CRREL - US Army Cold Regions Research and Engineering Laboratory, and the USGS). LMMP will utilize data predominately from the Lunar Reconnaissance Orbiter, but also historical and international lunar mission data (e.g. Apollo, Lunar Orbiter, Kaguya, Chandrayaan-1), as available and appropriate, to meet Constellation’s data needs. LMMP will provide access to this data through a single intuitive and easy to use NASA portal that transparently accesses appropriately sanctioned portions of the widely dispersed and distributed collections of lunar data, products and tools. Two visualization systems are being developed, a web-based system called Lunar Mapper, and a desktop client, ILIADS, which will be downloadable from the LMMP portal. LMMP will provide such products as local and regional imagery and DEMs, hazard assessment maps, lighting and gravity models, and resource maps. We are working closely with the LRO team to prevent duplication of efforts and to ensure the highest quality data products. While Constellation is our primary customer, LMMP is striving to be as useful as possible to the lunar science community, the lunar commercial community, the lunar education and public outreach (E/PO) community, and anyone else interested in accessing or utilizing lunar data. A beta version of the portal and visualization systems is expected to be released in late 2009, with a version 1 release planned for early 2011.
Standardized UXO Technology Demonstration Site Woods Scoring Record Number 902 (Sky Research, Inc.)
2008-08-01
endpoint. 8 2) A metallic pin-flag is placed over the midpoint. 3) The operator logs data along the same path, first traveling north, and then...data and after completion of data collection. This test involves traverses across a known point located away from buried UXO or other metallic ...areas, dips, ruts and obstructions that challenge platform systems or hand held detectors . The challenges include a gravel road, wet areas and trees
Photograph of Apollo 17 Lunar Roving Vehicle traverses
1972-10-01
S72-03145 (October 1972) --- A vertical view of the Apollo 17 Taurus-Littrow site with an overlay to illustrate the three planned Apollo 17 traverses using the Lunar Roving Vehicle (LRV). The EVA-1 traverse has a single station (1); the EVA-2 traverse has four stations (2,3,4,5); and the EVA-3 traverse has five stations (6,7,8,9,10). Stations 10-A and 10-B are alternate locations for Station 10. In addition to the major stations mentioned above, brief stops are planned for sampling between stations using the LRV sampler tool (note diamond-shaped figures), and for deploying explosive charges associated with the Lunar Seismic Profiling Experiment (LSPE - note black x-marks).
NASA Astrophysics Data System (ADS)
Dalton, J. B.; Prockter, L. M.; Shirley, J. H.; Phillips, C. B.; Kamp, L.
2011-12-01
Mannanan is a 22-km-diameter impact crater located at 3 N, 240 W on Europa's orbital trailing side. Detailed high resolution geologic mapping by Moore et al. (2001) revealed the likely presence of extensive deposits of impact melt materials largely filling the crater floor, together with surrounding continuous ejecta deposits that may have been excavated from Europa's interior. Terrains surrounding Mannanàn include some of Europa's visibly darkest surfaces, with extensive areas of chaos, traversed by the prominent structure of Belus Linea. The Mannannàn impact crater and its surrounding areas were imaged during the C3 orbital encounter of the Galileo Mission by the orbiter's Near-Infrared Mapping Spectrometer (NIMS). This NIMS observation (C3ENLINEA01A) has not been subjected to a detailed investigation until now, possibly due to the presence of moderate levels of radiation noise. A "despiked" version of this observation has been produced using methods described in Shirley et al. (2010). In addition, new geologic mapping precisely registered to the NIMS coverage of Manannàn and its surroundings allows the extraction of high-quality near-infrared spectra that are specific to individual geologic units and morphological features. We will present linear mixture modeling solutions for the compositions of several of Manannàn's key stratigraphic units, including the crater floor deposits and the adjacent chaos and linea materials. We will interpret these results in the context of ongoing investigations of the interplay of exogenic and endogenic influences on the surface composition of Europa. This work was performed at the Jet Propulsion Laboratory-California Institute of Technology, Johns Hopkins University-Applied Physics Laboratory, and the SETI Institute under a contract with NASA. Support by NASA's Outer Planets Research program is gratefully acknowledged. Moore, J. M. and 25 others 2001. Impact Features on Europa: Results of the Galileo Europa Mission (GEM), Icarus 151, 93-111. Shirley, J. H., J. B. Dalton III, L. M. Prockter, and L. W. Kamp 2010. Europa's ridged plains and smooth low albedo plains: Distinctive compositions and compositional gradients at the leading side-trailing side boundary, Icarus 210, 358-384, doi:10.1016/j.icarus.2010.06.018.
NASA Astrophysics Data System (ADS)
Albertson, J. D.
2015-12-01
Methane emissions from underground pipeline leaks remain an ongoing issue in the development of accurate methane emission inventories for the natural gas supply chain. Application of mobile methods during routine street surveys would help address this issue, but there are large uncertainties in current approaches. In this paper, we describe results from a series of near-source (< 30 m) controlled methane releases where an instrumented van was used to measure methane concentrations during both fixed location sampling and during mobile traverses immediately downwind of the source. The measurements were used to evaluate the application of EPA Method 33A for estimating methane emissions downwind of a source and also to test the application of a new probabilistic approach for estimating emission rates from mobile traverse data.
Singh, Ajay V; Gollner, Michael J
2016-06-01
Modeling the realistic burning behavior of condensed-phase fuels has remained out of reach, in part because of an inability to resolve the complex interactions occurring at the interface between gas-phase flames and condensed-phase fuels. The current research provides a technique to explore the dynamic relationship between a combustible condensed fuel surface and gas-phase flames in laminar boundary layers. Experiments have previously been conducted in both forced and free convective environments over both solid and liquid fuels. A unique methodology, based on the Reynolds Analogy, was used to estimate local mass burning rates and flame heat fluxes for these laminar boundary layer diffusion flames utilizing local temperature gradients at the fuel surface. Local mass burning rates and convective and radiative heat feedback from the flames were measured in both the pyrolysis and plume regions by using temperature gradients mapped near the wall by a two-axis traverse system. These experiments are time-consuming and can be challenging to design as the condensed fuel surface burns steadily for only a limited period of time following ignition. The temperature profiles near the fuel surface need to be mapped during steady burning of a condensed fuel surface at a very high spatial resolution in order to capture reasonable estimates of local temperature gradients. Careful corrections for radiative heat losses from the thermocouples are also essential for accurate measurements. For these reasons, the whole experimental setup needs to be automated with a computer-controlled traverse mechanism, eliminating most errors due to positioning of a micro-thermocouple. An outline of steps to reproducibly capture near-wall temperature gradients and use them to assess local burning rates and heat fluxes is provided.
Self-Supervised Learning of Terrain Traversability from Proprioceptive Sensors
NASA Technical Reports Server (NTRS)
Bajracharya, Max; Howard, Andrew B.; Matthies, Larry H.
2009-01-01
Robust and reliable autonomous navigation in unstructured, off-road terrain is a critical element in making unmanned ground vehicles a reality. Existing approaches tend to rely on evaluating the traversability of terrain based on fixed parameters obtained via testing in specific environments. This results in a system that handles the terrain well that it trained in, but is unable to process terrain outside its test parameters. An adaptive system does not take the place of training, but supplements it. Whereas training imprints certain environments, an adaptive system would imprint terrain elements and the interactions amongst them, and allow the vehicle to build a map of local elements using proprioceptive sensors. Such sensors can include velocity, wheel slippage, bumper hits, and accelerometers. Data obtained by the sensors can be compared to observations from ranging sensors such as cameras and LADAR (laser detection and ranging) in order to adapt to any kind of terrain. In this way, it could sample its surroundings not only to create a map of clear space, but also of what kind of space it is and its composition. By having a set of building blocks consisting of terrain features, a vehicle can adapt to terrain that it has never seen before, and thus be robust to a changing environment. New observations could be added to its library, enabling it to infer terrain types that it wasn't trained on. This would be very useful in alien environments, where many of the physical features are known, but some are not. For example, a seemingly flat, hard plain could actually be soft sand, and the vehicle would sense the sand and avoid it automatically.
Singh, Ajay V.; Gollner, Michael J.
2016-01-01
Modeling the realistic burning behavior of condensed-phase fuels has remained out of reach, in part because of an inability to resolve the complex interactions occurring at the interface between gas-phase flames and condensed-phase fuels. The current research provides a technique to explore the dynamic relationship between a combustible condensed fuel surface and gas-phase flames in laminar boundary layers. Experiments have previously been conducted in both forced and free convective environments over both solid and liquid fuels. A unique methodology, based on the Reynolds Analogy, was used to estimate local mass burning rates and flame heat fluxes for these laminar boundary layer diffusion flames utilizing local temperature gradients at the fuel surface. Local mass burning rates and convective and radiative heat feedback from the flames were measured in both the pyrolysis and plume regions by using temperature gradients mapped near the wall by a two-axis traverse system. These experiments are time-consuming and can be challenging to design as the condensed fuel surface burns steadily for only a limited period of time following ignition. The temperature profiles near the fuel surface need to be mapped during steady burning of a condensed fuel surface at a very high spatial resolution in order to capture reasonable estimates of local temperature gradients. Careful corrections for radiative heat losses from the thermocouples are also essential for accurate measurements. For these reasons, the whole experimental setup needs to be automated with a computer-controlled traverse mechanism, eliminating most errors due to positioning of a micro-thermocouple. An outline of steps to reproducibly capture near-wall temperature gradients and use them to assess local burning rates and heat fluxes is provided. PMID:27285827
Exploring the Nuclear Phase Diagram with Beam Energy Scans
NASA Astrophysics Data System (ADS)
Horvat, Stephen
2017-04-01
The nuclear phase diagram is mapped using beam energy scans of relativistic heavy-ion collisions. This mapping is possible because different collision energies develop along different trajectories through the phase diagram. High energy collisions will evolve though a crossover phase transition according to lattice QCD, but lower collision energies may traverse a first order phase transition. There are hints for this first order phase transition and its critical endpoint, but further measurements and theoretical guidance is needed. In addition to mapping the phase transition, beam energy scans allow us to see if we can turn off the signatures of deconfinement. If an observable is a real signature for the formation of the deconfined state called quark-gluon plasma, then it should turn off at sufficiently low collision energies. In this summary talk I will show the current state of the field using beam energy scan results from RHIC and SPS, I will show where precise theoretical guidance is needed for understanding recent measurements, and I will motivate the need for more data and new measurements from FAIR, NICA, RHIC, and the SPS.
Induced vibrations facilitate traversal of cluttered obstacles
NASA Astrophysics Data System (ADS)
Thoms, George; Yu, Siyuan; Kang, Yucheng; Li, Chen
When negotiating cluttered terrains such as grass-like beams, cockroaches and legged robots with rounded body shapes most often rolled their bodies to traverse narrow gaps between beams. Recent locomotion energy landscape modeling suggests that this locomotor pathway overcomes the lowest potential energy barriers. Here, we tested the hypothesis that body vibrations induced by intermittent leg-ground contact facilitate obstacle traversal by allowing exploration of locomotion energy landscape to find this lowest barrier pathway. To mimic a cockroach / legged robot pushing against two adjacent blades of grass, we developed an automated robotic system to move an ellipsoidal body into two adjacent beams, and varied body vibrations by controlling an oscillation actuator. A novel gyroscope mechanism allowed the body to freely rotate in response to interaction with the beams, and an IMU and cameras recorded the motion of the body and beams. We discovered that body vibrations facilitated body rolling, significantly increasing traversal probability and reducing traversal time (P <0.0001, ANOVA). Traversal probability increased with and traversal time decreased with beam separation. These results confirmed our hypothesis and support the plausibility of locomotion energy landscapes for understanding the formation of locomotor pathways in complex 3-D terrains.
Terrain Traversing Device Having a Wheel with Microhooks
NASA Technical Reports Server (NTRS)
Parness, Aaron (Inventor); McKenzie, Clifford F. (Inventor)
2014-01-01
A terrain traversing device includes an annular rotor element with a plurality of co-planar microspine hooks arranged on the periphery of the annular rotor element. Each microspine hook has an independently flexible suspension configuration that permits the microspine hook to initially engage an irregularity in a terrain surface at a preset initial engagement angle and subsequently engage the irregularity with a continuously varying engagement angle when the annular rotor element is rotated for urging the terrain traversing device to traverse a terrain surface.
Geologic Traverse Planning for Apollo Missions
NASA Technical Reports Server (NTRS)
Lofgren, Gary
2012-01-01
The science on Apollo missions was overseen by the Science Working Panel (SWP), but done by multiple PIs. There were two types of science, packages like the Apollo Lunar Surface Experiment Package (ALSEP) and traverse science. Traverses were designed on Earth for the astronauts to execute. These were under direction of the Lunar Surface PI, but the agreed traverse was a cooperation between the PI and SWP. The landing sites were selected by a different designated committee, not the SWP, and were based on science and safety.
NASA Astrophysics Data System (ADS)
Khodzher, T. V.; Golobokova, L. P.; Osipov, E. Yu.; Shibaev, Yu. A.; Lipenkov, V. Ya.; Osipova, O. P.; Petit, J. R.
2014-05-01
In January of 2008, during the 53rd Russian Antarctic Expedition, surface snow samples were taken from 13 shallow (0.7 to 1.5 m depth) snow pits along the first tractor traverse from Progress to Vostok stations, East Antarctica. Sub-surface snow/firn layers are dated from 2.1 to 18 yr. The total length of the coast to inland traverse is more than 1280 km. Here we analysed spatial variability of concentrations of sulphate ions and elements and their fluxes in the snow deposited within the 2006-2008 time interval. Anions were analysed by high-performance liquid chromatography (HPLC), and the determination of selected metals, including Na, K, Mg, Ca and Al, was carried out by mass spectroscopy with atomization by induced coupled plasma (ICP-MS). Surface snow concentration records were examined for trends versus distance inland, elevation, accumulation rate and slope gradient. Na shows a significant positive correlation with accumulation rate, which decreases as distance from the sea and altitude increase. K, Ca and Mg concentrations do not show any significant relationship either with distance inland or with elevation. Maximal concentrations of these elements with a prominent Al peak are revealed in the middle part of the traverse (500-600 km from the coast). Analysis of element correlations and atmospheric circulation patterns allow us to suggest their terrestrial origin (e.g. aluminosilicates carried as a continental dust) from the Antarctic nunatak areas. Sulphate concentrations show no significant relationship with distance inland, elevation, slope gradient and accumulation rate. Non-sea salt secondary sulphate is the most important contribution to the total sulphate budget along the traverse. Sulphate of volcanic origin attributed to the Pinatubo eruption (1991) was revealed in the snow pit at 1276 km (depth 120-130 cm).
Comparison of pitot traverses taken at varying distances downstream of obstructions.
Guffey, S E; Booth, D W
1999-01-01
This study determined the deviations between pitot traverses taken under "ideal" conditions--at least seven duct diameter's lengths (i.e., distance = 7D) from obstructions, elbows, junction fittings, and other disturbances to flows--with those taken downstream from commonplace disturbances. Two perpendicular 10-point, log-linear velocity pressure traverses were taken at various distances downstream of tested upstream conditions. Upstream conditions included a plain duct opening, a junction fitting, a single 90 degrees elbow, and two elbows rotated 90 degrees from each other into two orthogonal planes. Airflows determined from those values were compared with the values measured more than 40D downstream of the same obstructions under ideal conditions. The ideal measurements were taken on three traverse diameters in the same plane separated by 120 degrees in honed drawn-over-mandrel tubing. In all cases the pitot tubes were held in place by devices that effectively eliminated alignment errors and insertion depth errors. Duct velocities ranged from 1500 to 4500 ft/min. Results were surprisingly good if one employed two perpendicular traverses. When the averages of two perpendicular traverses was taken, deviations from ideal value were 6% or less even for traverses taken as close as 2D distance from the upstream disturbances. At 3D distance, deviations seldom exceeded 5%. With single diameter traverses, errors seldom exceeded 5% at 6D or more downstream from the disturbance. Interestingly, percentage deviations were about the same at high and low velocities. This study demonstrated that two perpendicular pitot traverses can be taken as close as 3D from these disturbances with acceptable (< or = 5%) deviations from measurements taken under ideal conditions.
Results of gamma activity traverses made in process tube channels and VSR channels at 105-KW
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greene, M.C. Jr.
1955-02-03
Activity traverses were made at Hanford reactor 105-KW in VSR channels 23, 29, 37, 46, 55, 63 and 69 and in process channels 4669, 4569, 4668, 4670 and 4769. These traverses were made during cleaning operations to assist in the location of any contaminated material in these channels and again after completion of the cleaning operations to determine if all of the contaminated material was removed. Upon completion of the cleaning of the VSR channels and process channels activity traverses were made in all of the channels. The results of these traverses show that no detectable amounts of contaminated materialmore » were present in any of these channels. The traverses made in the VSR channels all show a large peak in the lower part of the pile indicating that the metal in the lower part of the pile received as much as five times the integrated exposure received by the metal in the upper half of the pile. 15 figs.« less
ERIC Educational Resources Information Center
Fulco, Charles
2017-01-01
The 2017 Total Solar Eclipse (TSE2017) will occur on August 21 in the continental United States, bringing totality to this area for the first time since 1979. The Moon's umbra will traverse from Oregon to South Carolina in about 90 minutes, bringing an eerie darkness to 14 states coast-to-coast and a partial eclipse to every part of the country…
Aquatic insects as Bioindicators of land Use Change in the Grand Traverse Bay Area of Michigan
Robert A. Haack; Toby R. Petrice; Sheridan K. Haack; David Hyndman; David Long; Bryan Pijanowski
2000-01-01
In 1996, the US-Canadian International Joint Commission identified five key stresses impacting the Great Lakes Basin Ecosystem: nutrient inputs (e.g., phosphorous and nitrogen), persistent toxic substances, physical alterations (e.g., sedimentation, infiltration, runoff, water levels), human activities and values (as manifested in land-use change, populations growth,...
An Analysis of the Safety Issues Involving Local School Children as Pedestrians. Revised.
ERIC Educational Resources Information Center
Ducote, Kenneth J.
The New Orleans Public Schools' Department of Planning has been concerned with school children as pedestrians for the past five years. The safety issues include the streets, the drivers, and the children. First, the streets contribute to the hazard because many major streets traverse residential areas; many streets serve as major commuter…
Dynamic traversal of large gaps by insects and legged robots reveals a template.
Gart, Sean W; Yan, Changxin; Othayoth, Ratan; Ren, Zhiyi; Li, Chen
2018-02-02
It is well known that animals can use neural and sensory feedback via vision, tactile sensing, and echolocation to negotiate obstacles. Similarly, most robots use deliberate or reactive planning to avoid obstacles, which relies on prior knowledge or high-fidelity sensing of the environment. However, during dynamic locomotion in complex, novel, 3D terrains, such as a forest floor and building rubble, sensing and planning suffer bandwidth limitation and large noise and are sometimes even impossible. Here, we study rapid locomotion over a large gap-a simple, ubiquitous obstacle-to begin to discover the general principles of the dynamic traversal of large 3D obstacles. We challenged the discoid cockroach and an open-loop six-legged robot to traverse a large gap of varying length. Both the animal and the robot could dynamically traverse a gap as large as one body length by bridging the gap with its head, but traversal probability decreased with gap length. Based on these observations, we developed a template that accurately captured body dynamics and quantitatively predicted traversal performance. Our template revealed that a high approach speed, initial body pitch, and initial body pitch angular velocity facilitated dynamic traversal, and successfully predicted a new strategy for using body pitch control that increased the robot's maximal traversal gap length by 50%. Our study established the first template of dynamic locomotion beyond planar surfaces, and is an important step in expanding terradynamics into complex 3D terrains.
Dust Measurements by the Student Dust Counter (SDC) onboard the New Horizons Mission
NASA Astrophysics Data System (ADS)
James, David; Horanyi, Mihaly; Poppe, Andrew
The Venetia Burney Student Dust Counter (VSDC) on the New Horizons spacecraft is a dust impact detector designed to map the interplanetary dust distribution along the trajectory of the New Horizons spacecraft as it traverses our solar system. VSDC is the first student built instrument on a deep space mission and is currently operated by a small group of undergraduate and graduate students at the Laboratory for Atmospheric and Space Physics (LASP), University of Colorado. VSDC is based on permanently polarized thin plastic film sensors that generate an electrical signal when an impacting dust particle penetrates them. The total surface area is about 0.1 square meters and the detection threshold is about 1 micron in radius. By the time of this meeting (7/2008), VSDC will have operated for about 500 days, covering an approximate distance of 1.2 to 10.5 AU. In this talk, we will briefly review the VSDC instrument, including the in-flight calibrations and tests. We will report on the measured spatial and size distribution of interplanetary dust particles before and after the New Horizons encounter with Jupiter. These data will also be compared to earlier measurements by Ulysses, Galileo and Cassini.
NASA Astrophysics Data System (ADS)
Tate, C. G.; Moersch, J.; Jun, I.; Ming, D. W.; Mitrofanov, I.; Litvak, M.; Behar, A.; Boynton, W. V.; Deflores, L.; Drake, D.; Ehresmann, B.; Fedosov, F.; Golovin, D.; Hardgrove, C.; Harshman, K.; Hassler, D. M.; Kozyrev, A. S.; Kuzmin, R.; Lisov, D.; Malakhov, A.; Milliken, R.; Mischna, M.; Mokrousov, M.; Nikiforov, S.; Sanin, A. B.; Starr, R.; Varenikov, A.; Vostrukhin, A.; Zeitlin, C.
2015-12-01
The Dynamic Albedo of Neutrons (DAN) experiment on the Mars Science Laboratory (MSL) rover Curiosity is designed to detect neutrons to determine hydrogen abundance within the subsurface of Mars (Mitrofanov, I.G. et al. [2012]. Space Sci. Rev. 170, 559-582. http://dx.doi.org/10.1007/s11214-012-9924-y; Litvak, M.L. et al. [2008]. Astrobiology 8, 605-613. http://dx.doi.org/10.1089/ast.2007.0157). While DAN has a pulsed neutron generator for active measurements, in passive mode it only measures the leakage spectrum of neutrons produced by the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) and Galactic Cosmic Rays (GCR). DAN passive measurements provide better spatial coverage than the active measurements because they can be acquired while the rover is moving. Here we compare DAN passive-mode data to models of the instrument's response to compositional differences in a homogeneous regolith in order to estimate the water equivalent hydrogen (WEH) content along the first 200 sols of Curiosity's traverse in Gale Crater, Mars. WEH content is shown to vary greatly along the traverse. These estimates range from 0.5 ± 0.1 wt.% to 3.9 ± 0.2 wt.% for fixed locations (usually overnight stops) investigated by the rover and 0.6 ± 0.2 wt.% to 7.6 ± 1.3 wt.% for areas that the rover has traversed while continuously acquiring DAN passive data between fixed locations. Estimates of WEH abundances at fixed locations based on passive mode data are in broad agreement with those estimated at the same locations using active mode data. Localized (meter-scale) anomalies in estimated WEH values from traverse measurements have no particular surface expression observable in co-located images. However at a much larger scale, the hummocky plains and bedded fractured units are shown to be distinct compositional units based on the hydrogen content derived from DAN passive measurements. DAN passive WEH estimates are also shown to be consistent with geologic models inferred from other MSL instruments, which indicate that fluvial/lacustrine activity occurred at certain locations (e.g., Yellowknife Bay).
DOT National Transportation Integrated Search
2002-10-01
Traversable Highways are routes that have been approved by the Legislation as future State : Highway Routes. These routes when constructed to the Department of Transportation (Caltrans) : standards, the California Transportation Commission (CTC) shal...
NASA Technical Reports Server (NTRS)
2004-01-01
This overview map made from Mars Orbiter camera images illustrates the path that the Mars Exploration Rover Spirit has taken from its first sol on the red planet through its 107th sol. As of sol 112 (April 26, 2004), Spirit has passed 'Missoula' crater and sits approximately 1,900 meters (1.18 miles) away from its destination at the western base of the 'Columbia Hills.' While most of Spirit's journey has been over the very angular rocks that make up the ejecta fields surrounding 'Bonneville' crater, the rover's next 50 or so sols will be spent traversing over martian plains that are dominated by rounder, vesicle-filled rocks.Wickramasinghe, Nilmini S; Goldberg, Steve
2008-01-01
To date, the adoption and diffusion of technology-enabled solutions to deliver better healthcare has been slow. There are many reasons for this. One of the most significant is that the existing methodologies that are normally used in general for Information and Communications Technology (ICT) implementations tend to be less successful in a healthcare context. This paper describes a knowledge-based adaptive mapping to realisation methodology to traverse successfully from idea to realisation rapidly and without compromising rigour so that success ensues. It is discussed in connection with trying to implement superior ICT-enabled approaches to facilitate superior Chronic Disease Management (CDM).
NASA Astrophysics Data System (ADS)
Yang, Yong
2008-12-01
In an actual levitation system composed of high temperature superconductors (HTSs) and permanent magnets (PMs), the levitating bodies may traverse in arbitrary directions. Many previous researchers assumed that the levitating bodies moved in a vertical direction or a lateral direction in order to simplify the problem. In this paper, the vertical and lateral forces acting on the PM are calculated by the modified frozen-image method when a PM above an HTS traverses in arbitrary directions. In order to study the effects of the movement directions on the vertical and lateral forces, comparisons of the forces that act on a PM traversing in a tilted direction with those that act on a PM traversing in a vertical direction or a lateral direction have been presented.
Dynamic traversal of high bumps and large gaps by a small legged robot
NASA Astrophysics Data System (ADS)
Gart, Sean; Winey, Nastasia; de La Tijera Obert, Rafael; Li, Chen
Small animals encounter and negotiate diverse obstacles comparable in size or larger than themselves. In recent experiments, we found that cockroaches can dynamically traverse bumps up to 4 times hip height and gaps up to 1 body length. To better understand the physics that governs these locomotor transitions, we studied a small six-legged robot negotiating high bumps and large gaps and compared it to animal observations. We found that the robot was able to traverse bumps as large as 1 hip height and gaps as wide as 0.5 body length. For the bump, the robot often climbed over to traverse when initial body yaw was small, but was often deflected laterally and failed to traverse when initial body yaw was large. A simple locomotion energy landscape model explained these observations. For the gap, traversal probability decreased with gap width, which was well explained by a simple Lagrangian model of a forward-moving rigid body falling over the gap edge. For both the bump and the gap, animal performance far exceeded that of the robot, likely due to their relatively higher running speeds and larger rotational oscillations prior to and during obstacle traversal. Differences between animal and robot obstacle negotiation behaviors revealed that animals used active strategies to overcome potential energy barriers.
NOAA Deepwater Exploration of the Marianas 2016: Pacific Plate, Mariana Trench, and Mariana Forearc
NASA Astrophysics Data System (ADS)
Fryer, P. B.; Glickson, D.; Kelley, C.; Drazen, J.; Stern, R. J.
2016-12-01
Legs 1 and 3 of NOAA Okeanos Explorer EX1605 made 18 (ROV) dives exploring the following: 7 Cretaceous-age, Pacific Plate guyots east of the Trench; 1 small volcano on a Pacific Plate fracture; 3 areas of the inner trench slope; 2 forearc serpentinite mud volcanoes; and 5 forearc fault blocks. The Pacific Plate guyots are heavily manganese encrusted. Part of the rationale for those dives was to make baseline characterization of biota and habitats before potential mining. These guyots had striking diversity and abundance of fauna. Dives on 2 guyots examined high-relief scarps, formed when both down-going plate and edifices fractured outboard of the trench. The scarp on one had Cretaceous reef sequences, whereas the other exposed layers of volcanics. The dive on a small (1 km diameter, 141 m high) volcano on a plate fracture near the trench affirmed that it was relatively young, maybe like Petit-Spot volcanoes east of the Japan Trench. A dive in a canyon west of Guam transitioned from a steep slope of volcanic talus to a gentle sediment-covered slope. The inner trench slope opposite the subducting guyot that exposes reef deposits, revealed similar sequences, suggesting that the guyot is being incorporated into the Mariana forearc. The other inner slope dive traversed talus with fragments of serpentinized peridotite and lies near a chain of forearc serpentinite mud volcanoes. The 2 serpentinite mud volcanoes explored have sedimented, apparently inactive, surfaces, though we recovered a serpentinized peridotite sample from one of them. Dives on the forearc fault blocks attest to dynamic vertical tectonism. Three in the northern forearc show sediment sequences of varying types and textures, all dipping trenchward. Spectacular mid-forearc fault scarps strike east-west, stair-stepping down southward and were traversed on 2 dives. We saw many sequences of indurated sediments. Mapping on Legs 2 and 3 of the expedition showed that these fault scarps are mirrored to the south by north-facing scarps. Thus, vertical tectonics on a grand scale has formed an immense and previously unknown graben across the forearc. These dive results provide a wealth of information for future research into the history of plate convergence processes associated with formation of the Mariana Trench in this Marine National Monument area.
NASA Technical Reports Server (NTRS)
2005-01-01
Data from a portion of the imagery acquired by the Multi-angle Imaging SpectroRadiometer's vertical-viewing (nadir) camera during 2000-2002 were combined to create this cloud-free natural-color mosaic of southwestern Europe and northwestern Morocco and Algeria. The image extends from 48oN, 16oW in the northwest to 32oN, 8oE in the southeast. It is displayed in Albers conic equal-area projection (a projection which is frequently used for equal-area maps of regions that are predominantly east-west in extent). From the northeast, the image traverses a portion of the Swiss Alps (partially snow-covered) and a small part of Italy's Po Valley. The northern portion of the image also includes the western coast of France and much of southern and southwestern France's undulating terrain, which continues until reaching the hills of the Pyrenees. The Pyrenees act as the natural frontier to the Iberian Peninsula -- a landmass comprised of Spain and Portugal. The Peninsular landscapes are extremely varied, with some almost desert-like, others green and fertile. About half of Spain is situated atop a high plain, known as the Central Plateau, and many mountain ranges, rivers, geological basement rock and vegetation types are found across this great plateau. The largest alluvial plain is Andalusia in the south, where the valley of the Guadalquivir River is shut in by mountain ranges on every side except the southwest, where the valley descends to the Atlantic. The islands of Mallorca, Menorca and Ibiza are Spanish territories in the western Mediterranean. At the Strait of Gibralter, Spain and Morocco very nearly kiss, and Morocco appears relatively verdant along its northern coastal corner. The rugged Atlas Mountain ranges traverse northern Algeria and Morocco. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. This data product was generated from a portion of the imagery acquired during 2000-2002. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.Surface-Based 3d measurements of aeolian bedforms on Mars
NASA Astrophysics Data System (ADS)
Balme, Matthew; Robson, Ellen; Barnes, Robert; Huber, Ben; Butcher, Frances; Fawdon, Peter; Gupta, Sanjeev; Paar, Gerhard
2017-04-01
The surface of Mars hosts many different types of aeolian bedforms, from small wind-ripples with cm-scale wavelength, through decametre-scale "Transverse Aeolian Ridges" (TARs), to km-scale dunes. To date, all mobile Mars surface-missions ('Rovers') have encountered aeolian bedforms of one kind or another. Aeolian deposits of loose, unconsolidated material provide hazards to Mars Rovers: sinkage into the aeolian material and enhanced slippage can prevent traction and forward progress, forcing the Rover to backtrack (e.g., MER Opportunity) and can even 'trap' the rover ending the mission (e.g., MER Spirit). Here, we present morphometry measurements of meter-scale ripple-like bedforms on Mars, as observed by the MER Opportunity Rover during its traverse across the Meridiani Planum region of Mars. The aim is to assess whether there is a relationship between bedforms parameters that can be measured from orbit such as length and width, and bedform height, which can only be reliably measured from orbit for larger features such as TARs. If such a relationship can be found, it might allow estimates of ripple-height to be made from remote sensing data alone. This could help understand the formation mechanism and provide a better characterization of the hazard presented by these features. For much of the first 30 km of the traverse, Opportunity travelled across flat plains with meter-scale, ripple-like aeolian bedforms ("plains ripples") superposed upon them. During the traverse, the Rover acquired stereo imaging data of its surroundings using both its scientific Pancam cameras system and the navigational Navcam system. Using these data, and newly developed Pro3D™ and PRoViP™ software from Joanneum Research, we obtained Digital Elevation Models of many areas along the traverse, allowing us to measure the heights, widths and lengths of aeolian bedforms. In addition, the same bedforms were digitized from orbital HiRISE image data (25 cm/pix resolution) in ArcGIS software to check for agreement between the ground-based and space-based measurements. We found that there is a clear correlation between bedform height and bedform length (as measured perpendicular to the bedform ridge crest and thus, by inference, parallel to the bedform forming wind). We find that bedform height is about 1/15th of bedform length (or bedform wavelength where bedforms are "saturated") - in agreement with terrestrial measurements of granule ripples. This relationship, and the distribution of bedforms heights observed for different bedforms lengths, can be used to provide a probabilistic method of determining the height distributions of bedforms in a given area, simply by measuring their lengths from orbit. This will be useful for determining traversability by Rovers, and so is helpful both for landing site selection and strategic planning of Rover routes.
Physical exploration for uranium during 1951 in the Silver Reef district, Washington County, Utah
Stugard, Frederick
1954-01-01
During 1951 a joint exploration program of the most promising uraniferous areas in the Silver Reef district was made by the U.S. Geological Survey and the U.S. atomic Energy Commission. A U.S. Bureau of Mines drill crew, on contract to the Atomic Energy Commission, did 2,450 feet of diamond drilling under the geological supervision of the U.S. Geological Survey. The purpose of the drilling was to delineate broadly the favorable ground for commercial development of the uranium deposits. Ten drill holes were located around Pumpkin Point, which is the northeastern end of Buckeye Reef, to probe for extensions of small ore sheets mined on the Point in fine-grained sandstones of the Chinle formation. Three additional holes were located around Tecumseh Hill to probe for extensions of the small showings of uranium-bearing rocks of Buckeye Reef. Only one trace of uranium mineral was detected in the 13 drill holes by logging of drill cores, gamma-ray logging of the holes, and analysis of many core splits from favorable lithology. Extensive traversing with Geiger counters throughout the district and detailed geologic mapping of areas on Buckeye Reef and on East Reef indicate that the chances of discovering significant uranium deposits in the Silver Reef district are very poor, because of: highly variable lithology, closely faulted structure, and obliteration of the shallow uranium-bearing lenses by silver mining. Most of the available ore in the district was in the Pumpkin Point area and has been mined during 1950 to 1953. No ore reserves can be computed for the district before further development work. The most favorable remaining area in the district is now being explored by the operators with Atomic Energy Commission supervision.
Centimeter to Decimeter Size Spherical and Cylindrical Features in Gale Crater Sediments
NASA Technical Reports Server (NTRS)
Wiens, R. C.; Maurice, S.; Gasnault, O.; Clegg, S.; Fabre, C.; Nachon, M.; Rubin, D.; Goetz, W.; Mangold, N.; Schroeder, S.;
2015-01-01
The Curiosity rover traverse in Gale crater has explored a large series of sedimentary deposits in an ancient lake on Mars. Over the nine kilometers of traverse a recurrent observation has been southward-dipping sedimentary strata, from Shaler at the edge of Yellowknife Bay to the striated units near the Kimberley. Within the sedimentary strata cm- to decimeter- size hollow spheroidal objects and some apparent cylindrical objects have been observed. These features have not been seen by previous landed missions. The first of these were observed on sol 122 in the Gillespie Lake member at Yellowknife Bay. Additional hollow features were observed in the Point Lake outcrop in the same area. More recently a spherical and apparently hollow object, Winnipesaukee, was observed by ChemCam and Mastcam on sol 653. Here we describe the settings, morphology, and associated compositions, and we discuss possible origins of these objects.
Mapping the integrated Sachs-Wolfe effect
NASA Astrophysics Data System (ADS)
Manzotti, A.; Dodelson, S.
2014-12-01
On large scales, the anisotropies in the cosmic microwave background (CMB) reflect not only the primordial density field but also the energy gain when photons traverse decaying gravitational potentials of large scale structure, what is called the integrated Sachs-Wolfe (ISW) effect. Decomposing the anisotropy signal into a primordial piece and an ISW component, the main secondary effect on large scales, is more urgent than ever as cosmologists strive to understand the Universe on those scales. We present a likelihood technique for extracting the ISW signal combining measurements of the CMB, the distribution of galaxies, and maps of gravitational lensing. We test this technique with simulated data showing that we can successfully reconstruct the ISW map using all the data sets together. Then we present the ISW map obtained from a combination of real data: the NRAO VLA sky survey (NVSS) galaxy survey, temperature anisotropies, and lensing maps made by the Planck satellite. This map shows that, with the data sets used and assuming linear physics, there is no evidence, from the reconstructed ISW signal in the Cold Spot region, for an entirely ISW origin of this large scale anomaly in the CMB. However a large scale structure origin from low redshift voids outside the NVSS redshift range is still possible. Finally we show that future surveys, thanks to a better large scale lensing reconstruction will be able to improve the reconstruction signal to noise which is now mainly coming from galaxy surveys.
NASA Astrophysics Data System (ADS)
Okuma, S.; Ueda, T.; Mitsuhata, Y.; Uchida, T.
2012-12-01
The Geological Survey of Japan, AIST conducted a helicopter-borne EM and magnetic survey over tsunami invaded areas in northeast Japan 15 months after the 2011 off the Pacific coast of Tohoku Earthquake. The purpose of the survey is to map the electrical resistivity of the ground intruded by seawater during the tsunami on March 11, 2011 for its reutilization as farming lands and water assessment of the area. The survey was flown in June 2012 at an altitude of 60m above ground with a speed of 50km/h along survey and traverse lines spaced 100m and 1,000m apart, respectively. The airborne EM system (Fuguro Airborne Surveys' RESOLVE system) was installed in a bird and towed 30m below the helicopter. This is a frequency-domain system operated at five frequencies (340, 1,500, 6,900, 31,000, 140,000 Hz) in a horizontal coplanar configuration and at a frequency (3,300 Hz) in a coaxial configuration. The survey area is located at the border of Miyagi and Fukushima Prefectures along the Pacific coast in the southern part of the Sendai Plain and is divided into two sub-areas: Watari-Yamamoto-Shinchi area (area A) and Matsukawa-ura Bay area (area B). The area A is known for its production of high-quality strawberries on beach ridges and much fresh groundwater has been used for irrigation of strawberries and warming of strawberry greenhouses by water curtain. However, the salinity of groundwater from shallow irrigation wells in this area increased dramatically after the tsunami (Mori et al., 2012). Since it still remains at high level, there is an urgent need to find new water resources. Whereas, the area B is characterized by a beautiful lagoon called the Matsukawa-ura which is preserved as one of prefectural parks of Fukushima Prefecture. Rice fields occupy the areas west of the Matsukawa-ura and most of them were covered by seawater during the attack of the tsunami. Desalinization of the rice fields is being conducted intensively to resume rice farming in these fields. The observed electromagnetic data were processed and apparent resistivity maps were preliminary created for each frequencies. As for the apparent resistivity map at a frequency of 140,000Hz, very low resistivities less than 2 ohm-m are dominant over lagoons and river mouths along the coastline, indicating the existence of salt water wedge. Relatively low resistivities (8 - 22 ohm-m) range from close to the coastline up to 4km inland and are edged to the west by high resistivities (64 - 128 ohm-m), corresponding to the maximum flooded area as derived from aerial photos by the Geospatial Information Authority of Japan (2011). These low resistivities might be associated with the distribution of tsunami deposits with high salinity concentration. As the frequency becomes lower, low resistivities areas (< 8 ohm-m) extend to inland, indicating the existence of deep salt water wedges and/or fossil salt water. Further analyses such as a 1D inversion are being conducted and their results will be given at the presentation. Time-domain EM and high-density electrical surveys are also planned to be conducted on ground to verify the results by airborne surveys.
76 FR 9597 - Notice of Inventory Completion: Denver Museum of Nature & Science, Denver, CO
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-18
... the Duck Valley Reservation, Nevada; Sisseton-Wahpeton Oyate of the Lake Traverse Reservation, South...; Shoshone-Paiute Tribes of the Duck Valley Reservation, Nevada; Sisseton-Wahpeton Oyate of the Lake Traverse...; Shoshone-Paiute Tribes of the Duck Valley Reservation, Nevada; Sisseton-Wahpeton Oyate of the Lake Traverse...
Towards Human-Friendly Efficient Control of Multi-Robot Teams
NASA Technical Reports Server (NTRS)
Stoica, Adrian; Theodoridis, Theodoros; Barrero, David F.; Hu, Huosheng; McDonald-Maiers, Klaus
2013-01-01
This paper explores means to increase efficiency in performing tasks with multi-robot teams, in the context of natural Human-Multi-Robot Interfaces (HMRI) for command and control. The motivating scenario is an emergency evacuation by a transport convoy of unmanned ground vehicles (UGVs) that have to traverse, in shortest time, an unknown terrain. In the experiments the operator commands, in minimal time, a group of rovers through a maze. The efficiency of performing such tasks depends on both, the levels of robots' autonomy, and the ability of the operator to command and control the team. The paper extends the classic framework of levels of autonomy (LOA), to levels/hierarchy of autonomy characteristic of Groups (G-LOA), and uses it to determine new strategies for control. An UGVoriented command language (UGVL) is defined, and a mapping is performed from the human-friendly gesture-based HMRI into the UGVL. The UGVL is used to control a team of 3 robots, exploring the efficiency of different G-LOA; specifically, by (a) controlling each robot individually through the maze, (b) controlling a leader and cloning its controls to followers, and (c) controlling the entire group. Not surprisingly, commands at increased G-LOA lead to a faster traverse, yet a number of aspects are worth discussing in this context.
Astronauts Lovell and Haise during simulation of lunar traverse at Hawaii
1969-12-01
S70-20253 (December 1969) --- Astronauts James A. Lovell Jr. (left) commander, and Fred W. Haise Jr., lunar module pilot, carry out a simulation of a lunar traverse at Kilauea, Hawaii, site. Both crew members of NASA's third team of moon explorers were carrying cameras and communications equipment during the simulated traverse. They maintained contact with men in the roles of spacecraft throughout the traverse. Lovell holds a scoop for the Apollo Lunar Hand Tools (ALHT) and a gnomon, also for the ALHT is deployed in front of Haise. The ALHT carrier is at left background, (almost obscured by Lovell).
NASA Astrophysics Data System (ADS)
Bell, J. F.; Wellington, D. F.; Anderson, R. B.; Wolff, M. J.; Supulver, K. D.; Cantor, B. A.; Malin, M. C.
2012-12-01
The NASA Mars Reconnaissance Orbiter (MRO) spacecraft has been in its prime mapping orbit of the Red Planet since November 2006, a little over three Mars years. MRO's Mars Color Imager (MARCI) investigation has been acquiring wide-angle, approximately 1 km/pixel resolution multispectral images (from the UV to the short-wave near-IR) throughout the mission from the spacecraft's 300 km circular polar orbit. As of fall 2012, MARCI has acquired more than 25,000 image sequences, with its 180 degree field of view covering local solar times of approximately 15:00 +/- 2 hours at the equator. These images can be merged and map projected to provide near-global imaging coverage of Mars for almost every sol of the mission. These maps have been used to characterize and monitor changes in seasonal and interannual dust and water ice cloud opacity, growth and decay of local- to global-scale dust storms, and polar cap growth and recession. The data are also well-suited for studying small- to large-scale changes in surface albedo markings, important for understanding the nature of aeolian transport of dust and sand in the current Martian environment, as well as for modeling the radiative influence of the darker (warmer) or brighter (cooler) surface on local-scale atmospheric circulation and storm systems. We are using calibrated, map-projected, coregistered subsets of MARCI images to characterize and investigate surface albedo changes in a number of specific regions of interest, based on past Viking Orbiter, Hubble Space Telescope, and Mars Global Surveyor images of changing large-scale surface albedo patterns over recent decades, as well as recent surface missions that have characterized small-scale changes in surface albedo. Specific areas of study of large-scale changes include the dark areas Syrtis Major, Acidalia, Cimmeria, Sirenum, and Solis Lacus, and our initial focus areas for small-scale variations include regions in and around the landing sites of the Mars Exploration Rovers Spirit (Gusev crater) and Opportunity (Meridiani Planum), as well as Gale crater, the landing site for the Mars Science Laboratory rover Curiosity. Time-lapse animations of albedo changes in and around Gale crater, for example, reveal tens of km-scale changes in low albedo surface markings both within the crater (including near the rover's planned traverse path) as well as within the 500 km long low albedo wind streak south of the crater. Combined with morphologic, thermal inertia, and compositional/mineralogic constraints from other data sets, MARCI albedo variation measurements can help to constrain present rates of dust and sand transport in a variety of environments on Mars.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-26
... the New Airport Traffic Control Tower and Base Building at Cherry Capital Airport, Traverse City, MI... the New Airport Traffic Control Tower and Base Building at Cherry Capital Airport, Traverse City... Control Tower (ATCT) and Base Building at Cherry Capital Airport (TVC) in Traverse City, Michigan. The FAA...
A multi-pathway hypothesis for human visual fear signaling
Silverstein, David N.; Ingvar, Martin
2015-01-01
A hypothesis is proposed for five visual fear signaling pathways in humans, based on an analysis of anatomical connectivity from primate studies and human functional connectvity and tractography from brain imaging studies. Earlier work has identified possible subcortical and cortical fear pathways known as the “low road” and “high road,” which arrive at the amygdala independently. In addition to a subcortical pathway, we propose four cortical signaling pathways in humans along the visual ventral stream. All four of these traverse through the LGN to the visual cortex (VC) and branching off at the inferior temporal area, with one projection directly to the amygdala; another traversing the orbitofrontal cortex; and two others passing through the parietal and then prefrontal cortex, one excitatory pathway via the ventral-medial area and one regulatory pathway via the ventral-lateral area. These pathways have progressively longer propagation latencies and may have progressively evolved with brain development to take advantage of higher-level processing. Using the anatomical path lengths and latency estimates for each of these five pathways, predictions are made for the relative processing times at selective ROIs and arrival at the amygdala, based on the presentation of a fear-relevant visual stimulus. Partial verification of the temporal dynamics of this hypothesis might be accomplished using experimental MEG analysis. Possible experimental protocols are suggested. PMID:26379513
Phantom energy traversable wormholes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lobo, Francisco S.N.; Campo Grande, Ed. C8 1749-016 Lisbon
2005-04-15
It has been suggested that a possible candidate for the present accelerated expansion of the Universe is 'phantom energy'. The latter possesses an equation of state of the form {omega}{identical_to}p/{rho}<-1, consequently violating the null energy condition. As this is the fundamental ingredient to sustain traversable wormholes, this cosmic fluid presents us with a natural scenario for the existence of these exotic geometries. 'Note, however, that the notion of phantom energy is that of a homogeneously distributed fluid. Nevertheless, it can be extended to inhomogeneous spherically symmetric spacetimes, and it is shown that traversable wormholes may be supported by phantom energy.more » Because of the fact of the accelerating Universe, macroscopic wormholes could naturally be grown from the submicroscopic constructions that originally pervaded the quantum foam. One could also imagine an advanced civilization mining the cosmic fluid for phantom energy necessary to construct and sustain a traversable wormhole. In this context, we investigate the physical properties and characteristics of traversable wormholes constructed using the equation of state p={omega}{rho}, with {omega}<-1. We analyze specific wormhole geometries, considering asymptotically flat spacetimes and imposing an isotropic pressure. We also construct a thin shell around the interior wormhole solution, by imposing the phantom energy equation of state on the surface stresses. Using the 'volume integral quantifier' we verify that it is theoretically possible to construct these geometries with vanishing amounts of averaged null energy condition violating phantom energy. Specific wormhole dimensions and the traversal velocity and time are also deduced from the traversability conditions for a particular wormhole geometry. These phantom energy traversable wormholes have far-reaching physical and cosmological implications. For instance, an advanced civilization may use these geometries to induce closed timelike curves, consequently violating causality.« less
Explorative Observations of the Urban Climate System in the Rotterdam Metropolis
NASA Astrophysics Data System (ADS)
Jacobs, C. M.; van Hove, L. W.; Heusinkveld, B. G.; Steeneveld, G.; van Heerwaarden, C.; Elbers, J. A.
2009-12-01
Until recently, the Urban Heat Island (UHI) effect was thought to be relatively unimportant for Dutch conditions since The Netherlands are located in the mild Cfb climate, close to the sea. This view altered after the heat waves of 2003 and 2006 that caused an excess mortality between 1400 and 2200. The excess mortality was found in the cities in particular. Climate projections show that also in The Netherlands heat waves will likely become more frequent in the next decades, which may form an important threat to the livability in urban areas. However, information regarding UHI in Dutch cities is completely lacking, both from observational and model perspective, which hampers the design of suitable adaptation and heat mitigation strategies. In this study, an assessment of the intensity of UHI in the city of Rotterdam is made. The main aim is to assess whether or not heat stress already is or will be a critical issue in the Rotterdam area. Traverse measurements were performed in the city using two cargo bicycles as a mobile platform, equipped specifically for urban meteorology measurements. The cargo bicycles allow manoeuvring easily through the narrow streets in the city. They are equipped with a thermometer, a humidity sensor, a 2-dimensional sonic anemometer and a set of radiation sensors to measure solar radiation and infrared radiation exchange from six directions. The data are recorded at 1 Hz, and connected with concurrent GPS readings. The instruments are powered by a solar panel mounted on the baggage carrier. Measurements were performed along two previously determined routes through a number of characteristic urban districts, including an industrial area, an older residential area, a city park and the harbour area. The routes were photographed at fixed intervals from 50 cm above the ground with a fisheye lens pointing upwards. The observations were carried out during four 1-2h time intervals on 6 August 2009, a warm day with a maximum temperature of near 30°C. Data from the traverse measurements were compared with recordings from Zestienhoven, a nearby synoptic weather station outside the urban area. Satellite images and city maps were used to support the analyses. Furthermore, mesoscale model simulations for the Rotterdam area were performed. Preliminary results show that during daytime the city centre was 2 K warmer than Zestienhoven while the city park along the route was 2.4 K cooler. The air temperature perceived by humans was estimated to be 28°C at Zestienhoven and about 34°C in the city centre. During the late evening (22-24 LT), the city centre was ~5 K warmer than Zestienhoven and again, some locations near green spaces in the city were about 2 °C cooler. The difference in temperature between the city and the countryside amounted to more than 7 K during nocturnal hours. The preliminary results clearly demonstrate the existence of a considerable UHI in the city of Rotterdam and confirm the important role of green spaces in mitigating heat stress. The presentation will further highlight the measuring strategy and results from our analyses.
Vision-Based Real-Time Traversable Region Detection for Mobile Robot in the Outdoors.
Deng, Fucheng; Zhu, Xiaorui; He, Chao
2017-09-13
Environment perception is essential for autonomous mobile robots in human-robot coexisting outdoor environments. One of the important tasks for such intelligent robots is to autonomously detect the traversable region in an unstructured 3D real world. The main drawback of most existing methods is that of high computational complexity. Hence, this paper proposes a binocular vision-based, real-time solution for detecting traversable region in the outdoors. In the proposed method, an appearance model based on multivariate Gaussian is quickly constructed from a sample region in the left image adaptively determined by the vanishing point and dominant borders. Then, a fast, self-supervised segmentation scheme is proposed to classify the traversable and non-traversable regions. The proposed method is evaluated on public datasets as well as a real mobile robot. Implementation on the mobile robot has shown its ability in the real-time navigation applications.
Drilling of airborne radioactivity anomalies in Florida, Georgia, and South Carolina, 1954
Cathcart, J.B.
1954-01-01
From April 22 to May 19, 1953, airborne radioactivity surveys totalling 5,600 traverse miles were made in 10 areas in Florida (Moxham, 1954). Abnormal radioactivity was recorded in Bradford, Clay, DeSoto, Dixie, Lake, Marion, Orange, Sumter, Taylor, and Union Counties, Florida. Additional airborne surveys were made in the Spring of 1954 in Hardee and Manatee Counties, Florida, on the drainage of the Altamaha River in Georgia, and in the area of the old phosphate workings in and around Charleston County, South Carolina.
Terrain Traversing Device Having a Wheel with Microhooks
NASA Technical Reports Server (NTRS)
Wiltsie, Nicholas (Inventor); Carpenter, Kalind C. (Inventor); Parness, Aaron (Inventor)
2015-01-01
A terrain traversing device is described. The device includes an annular rotor element with a plurality of co-planar microspine hooks arranged on the periphery of the annular rotor element. Each microspine hook has an independently flexible suspension configuration that permits the microspine hook to initially engage an irregularity in a terrain surface at a preset initial engagement angle and subsequently engage the irregularity with a continuously varying engagement angle when the annular rotor element is rotated for urging the terrain traversing device to traverse a terrain surface. Improvements related to the design, fabrication and use of the microspine hooks in the device are also described.
NASA Astrophysics Data System (ADS)
Baawain, Mahad S.; Al-Futaisi, Ahmed M.; Ebrahimi, A.; Omidvarborna, Hamid
2018-04-01
Time Domain Electromagnetic (TDEM) survey as well as drilling investigations were conducted to identify possible contamination of a dumping site in an unsaturated zone located in Barka, Oman. The method was applied to evaluate conductivity of the contaminated plumes in hot and arid/semiarid region, where high temperatures commonly ranged between 35 and 50 °C. The drilling investigation was carried out over the survey area to verify the geophysical results. The low-resistivity zone (<80 Ωm), encountered near the subsurface, indicated plume migration caused by liquid waste disposal activities. The combination of TDEM survey results with the lithology of piezometers showed that higher resistivity (>90 Ωm) was correlated with compacted or cemented gravels and cobbles, particularly that of medium dense to very dense gravels and cobbles. Additionally, the TDEM profiles suggested that the plume migration followed a preferential flow path. The resistivity range 40-80 Ωm considered as contaminated areas; however, the drilling results showed the close resistivity domain in the depth >70 m below water table for some profiles (BL1, BL2, BL3, BL4 and BL5). The combined results of drilling wells, piezometers, and TDEM apparent resistivity maps showed a coincidence of the migrated leachate plume and water table. Predicted zone of the probable contamination was located at the depth of around 65 m and horizontal offset ranges 0-280 m, 80-240 m, and 40-85 m in the sounding traverses of BL4, BL6 and BL7, respectively.
NASA Astrophysics Data System (ADS)
Haskins, M. N.; Vollmer, F. W.; Rayburn, J. A.; Gurdak, J. J.
2010-12-01
To investigate joint control on hydrology as well as tectonic implications, we conducted a study of joint orientations near the Stony Clove and Warner Creek drainages of the Catskill Mountains, Eastern New York. Specific goals of this research were to determine joint control on stream orientations and groundwater flow, to compare results with previous studies in the area, and to investigate their tectonic significance. Trails, streams, and road cuts were traversed to locate bedrock outcrops whose positions were determined using topographic maps and a handheld GPS unit. Additional outcrops were located using aerial photographs and GIS data. Joint orientations were measured using a standard Brunton pocket transit. The data was analyzed using Orient (Vollmer, 2010), an orientation analysis program, to plot joint and stream orientations on rose diagrams. ArcGIS was used to produce topographic, hill-shade, and stream drainage maps. Over 500 joint orientations at over 100 outcrop stations were collected. The data were plotted on a rose diagrams, and two major joint sets were found, one with a mean strike of 021° and one with a mean strike of 096°. Stream orientations were also plotted on a rose diagram showing an axial mean of 022°, and indicate that the joint set with mean strike of 021 may have a significant control on stream orientations. The hill-shade maps also demonstrate clearly the strong control of jointing on the topography. The data collected in this research expands on previous joint orientation studies of Engelder and Geiser (1980) in the southwestern and central Catskills, and is similar to joint orientations found by Isachsen et al. (1977) in their study of the Panther Mountain circular structure, a possible impact-related feature. The origin of this jointing is thought to be related to Alleghanian (Permian) and possibly Acadian (Devonian) orogenic events.
Owen, Julia P.; Chang, Yi-Shin; Mukherjee, Pratik
2015-01-01
The structural connectome has emerged as a powerful tool to characterize the network architecture of the human brain and shows great potential for generating important new biomarkers for neurologic and psychiatric disorders. The edges of the cerebral graph traverse white matter to interconnect cortical and subcortical nodes, although the anatomic embedding of these edges is generally overlooked in the literature. Mapping the paths of the connectome edges could elucidate the relative importance of individual white matter tracts to the overall network topology of the brain and also lead to a better understanding of the effect of regionally-specific white matter pathology on cognition and behavior. In this work, we introduce edge density imaging (EDI), which maps the number of network edges that pass through every white matter voxel. Test-retest analysis shows good to excellent reliability for edge density (ED) measurements, with consistent results using different cortical and subcortical parcellation schemes and different diffusion MR imaging acquisition parameters. We also demonstrate that ED yields complementary information to both traditional and emerging voxel-wise metrics of white matter microstructure and connectivity, including fractional anisotropy, track density, fiber orientation dispersion and neurite density. Our results demonstrate spatially ordered variations of ED throughout the white matter, notably including greater ED in posterior than anterior cerebral white matter. The EDI framework is employed to map the white matter regions that are enriched with pathways connecting rich club nodes and also those with high densities of intra-modular and inter-modular edges. We show that periventricular white matter has particularly high ED and high densities of rich club edges, which is significant for diseases in which these areas are selectively affected, ranging from white matter injury of prematurity in infants to leukoaraiosis in the elderly. Using edge betweenness centrality, we identify specific white matter regions involved in a large number of shortest paths, some containing highly connected rich club edges while others are relatively isolated within individual modules. Overall, these findings reveal an intricate relationship between white matter anatomy and the structural connectome, motivating further exploration of EDI for biomarkers of cognition and behavior. PMID:25592996
NASA Lunar and Planetary Mapping and Modeling
NASA Astrophysics Data System (ADS)
Day, Brian; Law, Emily
2016-10-01
NASA's Lunar and Planetary Mapping and Modeling Portals provide web-based suites of interactive visualization and analysis tools to enable mission planners, planetary scientists, students, and the general public to access mapped lunar data products from past and current missions for the Moon, Mars, and Vesta. New portals for additional planetary bodies are being planned. This presentation will recap some of the enhancements to these products during the past year and preview work currently being undertaken.New data products added to the Lunar Mapping and Modeling Portal (LMMP) include both generalized products as well as polar data products specifically targeting potential sites for the Resource Prospector mission. New tools being developed include traverse planning and surface potential analysis. Current development work on LMMP also includes facilitating mission planning and data management for lunar CubeSat missions. Looking ahead, LMMP is working with the NASA Astromaterials Office to integrate with their Lunar Apollo Sample database to help better visualize the geographic contexts of retrieved samples. All of this will be done within the framework of a new user interface which, among other improvements, will provide significantly enhanced 3D visualizations and navigation.Mars Trek, the project's Mars portal, has now been assigned by NASA's Planetary Science Division to support site selection and analysis for the Mars 2020 Rover mission as well as for the Mars Human Landing Exploration Zone Sites, and is being enhanced with data products and analysis tools specifically requested by the proposing teams for the various sites. NASA Headquarters is giving high priority to Mars Trek's use as a means to directly involve the public in these upcoming missions, letting them explore the areas the agency is focusing upon, understand what makes these sites so fascinating, follow the selection process, and get caught up in the excitement of exploring Mars.The portals also serve as outstanding resources for education and outreach. As such, they have been designated by NASA's Science Mission Directorate as key supporting infrastructure for the new education programs selected through the division's recent CAN.
NASA Astrophysics Data System (ADS)
Howat, I.; Noh, M. J.; Porter, C. C.; Smith, B. E.; Morin, P. J.
2017-12-01
We are creating the Reference Elevation Model of Antarctica (REMA), a continuous, high resolution (2-8 m), high precision (accuracy better than 1 m) reference surface for a wide range of glaciological and geodetic applications. REMA will be constructed from stereo-photogrammetric Digital Surface Models (DSM) extracted from pairs of submeter resolution DigitalGlobe satellite imagery and vertically registred to precise elevations from near-coincident airborne LiDAR, ground-based GPS surveys and Cryosat-2 radar altimetry. Both a seamless mosaic and individual, time-stamped DSM strips, collected primarily between 2012 and 2016, will be distributed to enable change measurement. These data will be used for mapping bed topography from ice thickness, measuring ice thickness changes, constraining ice flow and geodynamic models, mapping glacial geomorphology, terrain corrections and filtering of remote sensing observations, and many other science tasks. Is will also be critical for mapping ice traverse routes, landing sites and other field logistics planning. REMA will also provide a critical elevation benchmark for future satellite altimetry missions including ICESat-2. Here we report on REMA production progress, initial accuracy assessment and data availability.
3D indoor modeling using a hand-held embedded system with multiple laser range scanners
NASA Astrophysics Data System (ADS)
Hu, Shaoxing; Wang, Duhu; Xu, Shike
2016-10-01
Accurate three-dimensional perception is a key technology for many engineering applications, including mobile mapping, obstacle detection and virtual reality. In this article, we present a hand-held embedded system designed for constructing 3D representation of structured indoor environments. Different from traditional vehicle-borne mobile mapping methods, the system presented here is capable of efficiently acquiring 3D data while an operator carrying the device traverses through the site. It consists of a simultaneous localization and mapping(SLAM) module, a 3D attitude estimate module and a point cloud processing module. The SLAM is based on a scan matching approach using a modern LIDAR system, and the 3D attitude estimate is generated by a navigation filter using inertial sensors. The hardware comprises three 2D time-flight laser range finders and an inertial measurement unit(IMU). All the sensors are rigidly mounted on a body frame. The algorithms are developed on the frame of robot operating system(ROS). The 3D model is constructed using the point cloud library(PCL). Multiple datasets have shown robust performance of the presented system in indoor scenarios.
A Vision System For A Mars Rover
NASA Astrophysics Data System (ADS)
Wilcox, Brian H.; Gennery, Donald B.; Mishkin, Andrew H.; Cooper, Brian K.; Lawton, Teri B.; Lay, N. Keith; Katzmann, Steven P.
1987-01-01
A Mars rover must be able to sense its local environment with sufficient resolution and accuracy to avoid local obstacles and hazards while moving a significant distance each day. Power efficiency and reliability are extremely important considerations, making stereo correlation an attractive method of range sensing compared to laser scanning, if the computational load and correspondence errors can be handled. Techniques for treatment of these problems, including the use of more than two cameras to reduce correspondence errors and possibly to limit the computational burden of stereo processing, have been tested at JPL. Once a reliable range map is obtained, it must be transformed to a plan view and compared to a stored terrain database, in order to refine the estimated position of the rover and to improve the database. The slope and roughness of each terrain region are computed, which form the basis for a traversability map allowing local path planning. Ongoing research and field testing of such a system is described.
A vision system for a Mars rover
NASA Technical Reports Server (NTRS)
Wilcox, Brian H.; Gennery, Donald B.; Mishkin, Andrew H.; Cooper, Brian K.; Lawton, Teri B.; Lay, N. Keith; Katzmann, Steven P.
1988-01-01
A Mars rover must be able to sense its local environment with sufficient resolution and accuracy to avoid local obstacles and hazards while moving a significant distance each day. Power efficiency and reliability are extremely important considerations, making stereo correlation an attractive method of range sensing compared to laser scanning, if the computational load and correspondence errors can be handled. Techniques for treatment of these problems, including the use of more than two cameras to reduce correspondence errors and possibly to limit the computational burden of stereo processing, have been tested at JPL. Once a reliable range map is obtained, it must be transformed to a plan view and compared to a stored terrain database, in order to refine the estimated position of the rover and to improve the database. The slope and roughness of each terrain region are computed, which form the basis for a traversability map allowing local path planning. Ongoing research and field testing of such a system is described.
Practopoiesis: or how life fosters a mind.
Nikolić, Danko
2015-05-21
The mind is a biological phenomenon. Thus, biological principles of organization should also be the principles underlying mental operations. Practopoiesis states that the key for achieving intelligence through adaptation is an arrangement in which mechanisms laying at a lower level of organization, by their operations and interaction with the environment, enable creation of mechanisms laying at a higher level of organization. When such an organizational advance of a system occurs, it is called a traverse. A case of traverse is when plasticity mechanisms (at a lower level of organization), by their operations, create a neural network anatomy (at a higher level of organization). Another case is the actual production of behavior by that network, whereby the mechanisms of neuronal activity operate to create motor actions. Practopoietic theory explains why the adaptability of a system increases with each increase in the number of traverses. With a larger number of traverses, a system can be relatively small and yet, produce a higher degree of adaptive/intelligent behavior than a system with a lower number of traverses. The present analyses indicate that the two well-known traverses - neural plasticity and neural activity - are not sufficient to explain human mental capabilities. At least one additional traverse is needed, which is named anapoiesis for its contribution in reconstructing knowledge e.g., from long-term memory into working memory. The conclusions bear implications for brain theory, the mind-body explanatory gap, and developments of artificial intelligence technologies. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.
Payload and Survivability Tradeoffs in the Presence of Risk
2013-06-01
9. SPONSORING /MONITORING AGENCY NAME(S) AND ADDRESS(ES) N/ A 10. SPONSORING/MONITORING AGENCY REPORT NUMBER 11. SUPPLEMENTARY NOTES The...DISTRIBUTION CODE A 13. ABSTRACT (maximum 200 words) The objective of this thesis research is to find an optimized throughput plan for ship...considering cargo ship size, quantity, speed, range, and risk when traversing through a designated travel area. Data collected from previous theses
2013-09-11
S70-56415 (December 1970) --- At Kapoho, Hawaii, astronauts David R. Scott (left), commander of the Apollo 15 lunar landing mission, and James B. Irwin, lunar module pilot, train at a designated lunar surface simulation area for their upcoming lunar landing mission. Wearing street clothes, but equipped with a Portable Life Support System (PLSS), the two rehearse for a selenological traverse. Here, they are inspecting a grapefruit-sized rock. Photo credit: NASA
The urban heat island in Akron, Ohio
Frank P. Martin; Grace L. Powell
1977-01-01
Data gathered by automobile traverse were used to describe the urban heat of Akron, Ohio. Observations were made at 2100 or 2200 EST on four nights-17 April, 11 July, 10 October, and 2 January. Weather conditions not conducive to heat-island development were avoided. Temperatures in the center of the heat island were 6 to 14?F warmer than rural areas outside the city....
Practical Application of Polarization and Light Control for Reduction of Reflected Glare.
ERIC Educational Resources Information Center
Crouch, C. L.; Kaufman, J. E.
1963-01-01
The role of reflected glare and visual viewing angles in near task performance is discussed, and following statements are reported--(1) a worker at a desk normally assumes a position in which his eyes traverse an area of work extending from a point approximately vertically below his eyes to a point not more than 40 degrees from the vertical, (2) a…
Future Exploration of the South Pole as Enabled by the Lunar Reconnaissance Orbiter
NASA Astrophysics Data System (ADS)
Speyerer, E. J.; Lawrence, S. J.; Stopar, J.
2016-12-01
The Lunar Reconnaissance Orbiter (LRO) launched in 2009 to collect the dataset required for future surface missions and to answer key questions about the lunar surface environment. In the first seven years of operations, the Lunar Reconnaissance Orbiter Camera (LROC) acquired over a million images of the lunar surface and collected key stereo observations for the production of meter-scale digital terrain models. Due to the configuration of the LRO orbit, LROC and the other onboard instruments have the opportunity to acquire observations at or near the poles every two hours. The lunar south polar region is an area of interest for future surface missions due to the benign thermal environment and areas of near-continuous illumination. These persistently illuminated regions are also adjacent to permanently shadowed areas (e.g. floors of craters and local depressions) that are of interest to both scientists and engineers prospecting for cold-trapped volatiles on or near the surface for future in situ resource utilization. Using a terramechanics model based on surface properties derived during the Apollo and Luna missions, we evaluated the accessibility of different science targets and the optimal traverse paths for a given set of waypoints. Assuming a rover that relies primarily on solar power, we identified a traverse that would keep the rover illuminated for 94.43% of the year between 1 January 2021 and 31 December 2021. Throughout this year-long period, the longest eclipse endured by the rover would last only 101 hours and the rover would move a total of 22.11 km with an average speed of 2.5 m/hr (max speed=30 m/hr). During this time the rover would be able to explore a variety of targets along the connecting ridge between Shackleton and de Gerlache craters. In addition to the southern polar regions, we are also examining traverses around other key exploration sites such as Marius Hills, Ina-D, Rima Parry, and the Mairan Domes in efforts to aid future mission planners and assess the requirements for future roving prospectors (e.g., maximum speed, maximum slope, etc.).
Future Exploration of the South Pole as Enabled by the Lunar Reconnaissance Orbiter
NASA Technical Reports Server (NTRS)
Speyerer, Emerson J.; Lawrence, Samuel J.; Stopar, Julie
2016-01-01
The Lunar Reconnaissance Orbiter (LRO) launched in 2009 to collect the dataset required for future surface missions and to answer key questions about the lunar surface environment. In the first seven years of operations, the Lunar Reconnaissance Orbiter Camera (LROC) acquired over a million images of the lunar surface and collected key stereo observations for the production of meter-scale digital terrain models. Due to the configuration of the LRO orbit, LROC and the other onboard instruments have the opportunity to acquire observations at or near the poles every two hours. The lunar south polar region is an area of interest for future surface missions due to the benign thermal environment and areas of near-continuous illumination. These persistently illuminated regions are also adjacent to permanently shadowed areas (e.g. floors of craters and local depressions) that are of interest to both scientists and engineers prospecting for cold-trapped volatiles on or near the surface for future in situ resource utilization. Using a terramechanics model based on surface properties derived during the Apollo and Luna missions, we evaluated the accessibility of different science targets and the optimal traverse paths for a given set of waypoints. Assuming a rover that relies primarily on solar power, we identified a traverse that would keep the rover illuminated for 94.43% of the year between 1 January 2021 and 31 December 2021. Throughout this year-long period, the longest eclipse endured by the rover would last only 101 hours and the rover would move a total of 22.11 km with an average speed of 2.5 m/hr (max speed=30 m/hr). During this time the rover would be able to explore a variety of targets along the connecting ridge between Shackleton and de Gerlache craters. In addition to the southern polar regions, we are also examining traverses around other key exploration sites such as Marius Hills, Ina-D, Rima Parry, and the Mairan Domes in efforts to aid future mission planners and assess the requirements for future roving prospectors (e.g., maximum speed, maximum slope, etc.).
1972-12-01
This photograph taken during the Apollo 17 mission (the last mission of the Apollo Program), depicts stiff plasticized maps being taped together and fastened by clamps to patch a broken fender of the Lunar Roving Vehicle (LRV). Powered by battery, the lightweight electric car greatly increased the range of mobility and productivity on the scientific traverses for astronauts. It weighed 462 pounds (77 pounds on the Moon) and could carry two suited astronauts, their gear and cameras, and several hundred pounds of bagged samples. The LRV's mobility was quite high. It could climb and descend slopes of about 25 degrees. The LRV was designed and developed by the Marshall Space Flight Center and built by the Boeing Company.
Fluvial to Lacustrine Facies Transitions in Gale Crater, Mars
NASA Technical Reports Server (NTRS)
Sumner, Dawn Y.; Williams, Rebecca M. E.; Schieber, Juergen; Palucis, Marisa C.; Oehler, Dorothy Z.; Mangold, Nicolas; Kah, Linda C.; Gupta, Sanjeev; Grotzinger, John P.; Grant, John A., III;
2015-01-01
NASA's Curiosity rover has documented predominantly fluvial sedimentary rocks along its path from the landing site to the toe of the Peace Vallis alluvial fan (0.5 km to the east) and then along its 8 km traverse across Aeolis Palus to the base of Aeolis Mons (Mount Sharp). Lacustrine facies have been identified at the toe of the Peace Vallis fan and in the lowermost geological unit exposed on Aeolis Mons. These two depositional systems provide end members for martian fluvial/alluvial-lacustrine facies models. The Peace Vallis system consisted of an 80 square kilometers alluvial fan with decimeter-thick, laterally continuous fluvial sandstones with few sedimentary structures. The thin lacustrine unit associated with the fan is interpreted as deposited in a small lake associated with fan runoff. In contrast, fluvial facies exposed over most of Curiosity's traverse to Aeolis Mons consist of sandstones with common dune-scale cross stratification (including trough cross stratification), interbedded conglomerates, and rare paleochannels. Along the southwest portion of the traverse, sandstone facies include south-dipping meter-scale clinoforms that are interbedded with finer-grained mudstone facies, interpreted as lacustrine. Sedimentary structures in these deposits are consistent with deltaic deposits. Deltaic deposition is also suggested by the scale of fluvial to lacustrine facies transitions, which occur over greater than 100 m laterally and greater than 10 m vertically. The large scale of the transitions and the predicted thickness of lacustrine deposits based on orbital mapping require deposition in a substantial river-lake system over an extended interval of time. Thus, the lowermost, and oldest, sedimentary rocks in Gale Crater suggest the presence of substantial fluvial flow into a long-lived lake. In contrast, the Peace Vallis alluvial fan onlaps these older deposits and overlies a major unconformity. It is one of the youngest deposits in the crater, and requires only short-lived, transient flows.
NASA Astrophysics Data System (ADS)
Lees, D. S.; Cohen, T.; Deans, M. C.; Lim, D. S. S.; Marquez, J.; Heldmann, J. L.; Hoffman, J.; Norheim, J.; Vadhavk, N.
2016-12-01
Minerva integrates three capabilities that are critical to the success of NASA analogs. It combines NASA's Exploration Ground Data Systems (xGDS) and Playbook software, and MIT's Surface Exploration Traverse Analysis and Navigation Tool (SEXTANT). Together, they help to plan, optimize, and monitor traverses; schedule and track activity; assist with science decision-making and document sample and data collection. Pre-mission, Minerva supports planning with a priori map data (e.g., UAV and satellite imagery) and activity scheduling. During missions, xGDS records and broadcasts live data to a distributed team who take geolocated notes and catalogue samples. Playbook provides live schedule updates and multi-media chat. Post-mission, xGDS supports data search and visualization for replanning and analysis. NASA's BASALT (Biologic Analog Science Associated with Lava Terrains) and FINESSE (Field Investigations to Enable Solar System Science and Exploration) projects use Minerva to conduct field science under simulated Mars mission conditions including 5 and 15 minute one-way communication delays. During the recent BASALT-FINESSE mission, two field scientists (EVA team) executed traverses across volcanic terrain to characterize and sample basalts. They wore backpacks with communications and imaging capabilities, and carried field portable spectrometers. The Science Team was 40 km away in a simulated mission control center. The Science Team monitored imaging (video and still), spectral, voice, location and physiological data from the EVA team via the network from the field, under communication delays. Minerva provided the Science Team with a unified context of operations at the field site, so they could make meaningful remote contributions to the collection of 10's of geotagged samples. Minerva's mission architecture will be presented with technical details and capabilities. Through the development, testing and application of Minerva, we are defining requirements for the design of future capabilities to support human and human-robotic missions to deep space and Mars.
EAST93: Geophysical traverse from the Transantarctic Mountains to the Wilkes Basin, East Antarctica
ten Brink, Uri S.; Bannister, Stephen
1995-01-01
The East Antarctic Seismic Traverse (EAST93) was a geophysical traverse designed to image the bedrock under the East Antarctic ice cap. The traverse started 10 km west of the Taylor Dome drill site and 25 km west of the exposed bedrock of the Transantarctic Mountains at Lashly Mt. and ended 323 km west of the drill site over the Wilkes subglacial basin (Fig. 1). The traverse was located subparallel to latitude 78° S starting 30-50 km north of the Victoria Land Traverse (1958-1959). It was carried out jointly by the U.S. Geological Survey and Stanford University, U.S.A., together with the Institute of Geological and Nuclear Sciences, and Victoria University, New Zealand, during December 1993 and January 1994. The geophysical traverse included 236 km of multichannel seismic reflection data at 150 m shot intervals, 312.5 km of gravity data collected at intervals of 2.1 km, 312.5 km of magnetic data (total field intensity) collected at average intervals of 0.5 km, and 205 km of ground penetrating radar at intervals of 77 m. Relative locations and elevations of the entire traverse were measured at intervals of 150 m by traditional surveying methods, and tied to three absolute locations measured by the Global Positioning System (GPS). EAST93 is the first large-scale geophysical traverse on the polar plateau to our knowledge since the early 1960s. As such, the experiment presented several logistical challenges: (1) how to collect regional seismic profiles during the short Antarctic summer; (2) how to keep the scientific instruments running with minimal protection in harsh conditions; and (3) how to combine daily moves of camp with full days of work. The scientific and logistical aspects of the project proceeded, in general, according to plan despite the harsh conditions and our lack of previous experience on the polar plateau. Two unanticipated problems affected the progress of the work: the strong wind which slowed seismic acquisition, and the break-down of one of the large traverse vehicles. The major operational lessons of this project are. (1) Primacord laid close to the surface is not an adequate seismic source for imaging under the thick East Antarctic ice sheet, despite positive prior tests on the Ross Ice Shelf. (2) It is necessary to reduce the 6-7 hours spent daily on camp move and other chores by integrating the living quarters into the working teams, and by improving vehicle warming methods and generator housing. The following report details the operational and logistical aspects of the work, the weather and ground conditions, the technical aspects of acquisition of geophysical data, and lessons and recommendations for future geophysical traverses.
Software Tool for Computing Maximum Von Mises Stress
NASA Technical Reports Server (NTRS)
Chen, Long Y.; Knutson, Kurt; Martin, Eric
2007-01-01
The maximum Van Mises stress and stress direction are of interest far analyzing launch accelerations such as with the Mass Acceleration Curves developed by JPL. Maximum launch stresses can be combined with appropriate load cases at consistent locations with resulting stress tensors. Maximum Van Mises stress is also of interest for understanding maximum operational loading such as traverse events. - For example, planetary traversing simulations may prescribe bounding acceleration values during traverse for a rover such as Mars Science Lab (MSL) in (X,Y,Z) of the rover. - Such accelerations can be really in any directions for many parts such as a mast or head mounted components which can be in numerous configurations and orientations when traversing a planet surface.
A Discrete Global Grid System Programming Language Using MapReduce
NASA Astrophysics Data System (ADS)
Peterson, P.; Shatz, I.
2016-12-01
A discrete global grid system (DGGS) is a powerful mechanism for storing and integrating geospatial information. As a "pixelization" of the Earth, many image processing techniques lend themselves to the transformation of data values referenced to the DGGS cells. It has been shown that image algebra, as an example, and advanced algebra, like Fast Fourier Transformation, can be used on the DGGS tiling structure for geoprocessing and spatial analysis. MapReduce has been shown to provide advantages for processing and generating large data sets within distributed and parallel computing. The DGGS structure is ideally suited for big distributed Earth data. We proposed that basic expressions could be created to form the atoms of a generalized DGGS language using the MapReduce programming model. We created three very efficient expressions: Selectors (aka filter) - A selection function that generate a set of cells, cell collections, or geometries; Calculators (aka map) - A computational function (including quantization of raw measurements and data sources) that generate values in a DGGS cell; and Aggregators (aka reduce) - A function that generate spatial statistics from cell values within a cell. We found that these three basic MapReduce operations along with a forth function, the Iterator, for horizontal and vertical traversing of any DGGS structure, provided simple building block resulting in very efficient operations and processes that could be used with any DGGS. We provide examples and a demonstration of their effectiveness using the ISEA3H DGGS on the PYXIS Studio.
Traverse Planning with Temporal-Spatial Constraints
NASA Technical Reports Server (NTRS)
Bresina, John L.; Morris, Paul H.; Deans, Mathew C.; Cohen, Tamar E.; Lees, David S.
2017-01-01
We present an approach to planning rover traverses in a domain that includes temporal-spatial constraints. We are using the NASA Resource Prospector mission as a reference mission in our research. The objective of this mission is to explore permanently shadowed regions at a Lunar pole. Most of the time the rover is required to avoid being in shadow. This requirement depends on where the rover is located and when it is at that location. Such a temporal-spatial constraint makes traverse planning more challenging for both humans and machines. We present a mixed-initiative traverse planner which addresses this challenge. This traverse planner is part of the Exploration Ground Data Systems (xGDS), which we have enhanced with new visualization features, new analysis tools, and new automation for path planning, in order to be applicable to the Re-source Prospector mission. The key concept that is the basis of the analysis tools and that supports the automated path planning is reachability in this dynamic environment due to the temporal-spatial constraints.
Stephens, G.C.; Evenson, E.B.; Detra, D.E.
1990-01-01
In mountainous regions containing extensive glacier systems there is a lack of suitable material for conventional geochemical sampling. As a result, in most geochemical sampling programs a few stream-sediment samples collected at, or near, the terminus of valley glaciers are used to evaluate the mineral potential of the glaciated area. We have developed and tested a technique which utilizes the medial moraines of valley glaciers for systematic geochemical exploration of the glacial catchment area. Moraine sampling provides geochemical information that is site-specific in that geochemical anomalies can be traced directly up-ice to bedrock sources. Traverses were made across the Trident and Susitna glaciers in the central Alaska Range where fine-grained (clay to sand size) samples were collected from each medial moraine. These samples were prepared and chemically analyzed to determine the concentration of specific elements. Fifty pebbles were collected at each moraine for archival purposes and for subsequent lithologic identification. Additionally, fifty cobbles and fifty boulders were examined and described at each sample site to determine the nature and abundance of lithologies present in the catchment area, the extent and nature of visible mineralization, the presence and intensity of hydrothermal alteration and the existence of veins, dikes and other minor structural features. Results from the central Alaska Range have delineated four distinct multi-element anomalies which are a response to potential mineralization up-ice from the medial moraine traverse. By integrating the lithologic, mineralogical and geochemical data the probable geological setting of the geochemical anomalies is determined. ?? 1990.
2014-01-01
In the current practice, to determine the safety factor of a slope with two-dimensional circular potential failure surface, one of the searching methods for the critical slip surface is Genetic Algorithm (GA), while the method to calculate the slope safety factor is Fellenius' slices method. However GA needs to be validated with more numeric tests, while Fellenius' slices method is just an approximate method like finite element method. This paper proposed a new method to determine the minimum slope safety factor which is the determination of slope safety factor with analytical solution and searching critical slip surface with Genetic-Traversal Random Method. The analytical solution is more accurate than Fellenius' slices method. The Genetic-Traversal Random Method uses random pick to utilize mutation. A computer automatic search program is developed for the Genetic-Traversal Random Method. After comparison with other methods like slope/w software, results indicate that the Genetic-Traversal Random Search Method can give very low safety factor which is about half of the other methods. However the obtained minimum safety factor with Genetic-Traversal Random Search Method is very close to the lower bound solutions of slope safety factor given by the Ansys software. PMID:24782679
Autonomous Rover Traverse and Precise Arm Placement on Remotely Designated Targets
NASA Technical Reports Server (NTRS)
Felder, Michael; Nesnas, Issa A.; Pivtoraiko, Mihail; Kelly, Alonzo; Volpe, Richard
2011-01-01
Exploring planetary surfaces typically involves traversing challenging and unknown terrain and acquiring in-situ measurements at designated locations using arm-mounted instruments. We present field results for a new implementation of an autonomous capability that enables a rover to traverse and precisely place an arm-mounted instrument on remote targets. Using point-and-click mouse commands, a scientist designates targets in the initial imagery acquired from the rover's mast cameras. The rover then autonomously traverse the rocky terrain for a distance of 10 - 15 m, tracks the target(s) of interest during the traverse, positions itself for approaching the target, and then precisely places an arm-mounted instrument within 2-3 cm from the originally designated target. The rover proceeds to acquire science measurements with the instrument. This work advances what has been previously developed and integrated on the Mars Exploration Rovers by using algorithms that are capable of traversing more rock-dense terrains, enabling tight thread-the-needle maneuvers. We integrated these algorithms on the newly refurbished Athena Mars research rover and fielded them in the JPL Mars Yard. We conducted 43 runs with targets at distances ranging from 5 m to 15 m and achieved a success rate of 93% for placement of the instrument within 2-3 cm.
AirSWOT flights and field campaigns for the 2017 Arctic-Boreal Vulnerability Experiment (ABoVE)
NASA Astrophysics Data System (ADS)
Smith, L. C.; Pavelsky, T.; Lettenmaier, D. P.; Gleason, C. J.; Pietroniro, A.; Applejohn, A.; Arvesen, J. C.; Bjella, K.; Carter, T.; Chao, R.; Cooley, S. W.; Cooper, M. G.; Cretaux, J. F.; Douglass, T.; Faria, D.; Fayne, J.; Fiset, J. M.; Goodman, S.; Hanna, B.; Harlan, M.; Langhorst, T.; Marsh, P.; Moreira, D. M.; Minear, J. T.; Onclin, C.; Overstreet, B. T.; Peters, D.; Pettit, J.; Pitcher, L. H.; Russell, M.; Spence, C.; Topp, S.; Turner, K. W.; Vimal, S.; Wilcox, E.; Woodward, J.; Yang, D.; Zaino, A.
2017-12-01
Some 50% of Canada and 80% of Alaska is thought to be underlain by permafrost, influencing the hydrology, ecology and carbon cycles of Arctic-Boreal landscapes. This influence includes enhanced presence of millions of lakes and wetlands, which release trace gases while supporting critical ecosystems and traditional subsistence economies. Permafrost is challenging to infer from remote sensing and difficult to sample in the field. A series of 2017 AirSWOT flights flown for the NASA Arctic-Boreal Vulnerability Experiment (ABoVE) will study whether small variations in water surface elevations (WSEs) of Arctic-Boreal lakes are sensitive to presence and/or disturbance of permafrost. AirSWOT is an experimental NASA airborne radar designed to map WSE and a precursor to SWOT, a forthcoming NASA/CNES/CSA satellite mission to map WSE globally with launch in 2021. The ABoVE AirSWOT flight experiments adopted long flight lines of the broader ABoVE effort to traverse broad spatial gradients of permafrost, climate, ecology, and geology. AirSWOT acquisitions consisted of long (1000s of kilometers) strips of Ka-band interferometric radar imagery, and high resolution visible/NIR imagery and DEMs from a digital Cirrus CIR camera. Intensive AirSWOT mapping and ground-based GPS field surveys were conducted at 11 field sites for eight study areas of Canada and Alaska: 1) Saint-Denis, Redberry Lake, North Saskatchewan River (Saskatchewan); 2) Peace-Athabasca Delta (Alberta); 3) Slave River Delta (N.W.T.); 4) Canadian Shield (Yellowknife area, Daring Lake, N.W.T.); 5) Mackenzie River (Inuvik-Tuktoyaktuk corridor, N.W.T.); 6) Old Crow Flats (Yukon Territory); 7) Sagavanirktok River (Alaska); 8) Yukon Flats (Alaska). Extensive ground campaigns were conducted by U.S. and Canadian collaborators to collect high quality surveys of lake WSE, river WSE and discharge, and shoreline locations. Field experiments included traditional and novel GPS surveying methods, including custom-built GPS buoys that float or drift upon water surfaces. Other ABoVE flight packages flown along AirSWOT lines included LVIS, AVIRIS, UAVSAR and AirMOSS. Processing and integration of ABoVE remote sensing and field datasets may provide new scientific insights about the influence of permafrost on surface water hydrology, over broad spatial scales.
Long range geoid control through the European GPS traverse: Final results
NASA Technical Reports Server (NTRS)
Torge, W.; Basic, T.; Denker, H.; Doliff, J.; Wenzel, H.-G.
1989-01-01
The European north-south Global Positioning System (GPS)-traverse proposed by IAG SSG 3.88, should control and improve the European geoid. This traverse follows first order leveling lines, included in the United European Leveling Network. From May to August 1986 and in July 1987, the central and northern part of this traverse (approx. 3000 km) was observed using up to four TI 4100 receivers, covering Austria, Federal Republic of Germany, Denmark, Sweden and Norway. Both traverse parts contain 71 stations with distances of about 50 km. In addition, 8 stations have been occupied for overlapping connections, and traverse links were established for connecting the fundamental stations Wettzell (VLBI and SLR) and Onsala (VLBI). Final results show a GPS observation precision of a few cm for loops of some 100 km circumference. After transformation of the GPS results to geoid heights using the leveled heights, comparisons with different existing gravimetric geoid determinations including geopotential models were performed. In addition, new geopotential models complete to degree and order 360 tailored to gravity data in Europe, and gravimetric geoid solutions using 6 x 10' mean gravity anomalies were investigated. The comparison with GPS and leveling yields rms discrepancies of + or - 0.1...0.2 m over 1000 km traverse sections for the best solutions, but a strong slope is existing in Sweden and southern Norway in almost all solutions, which is probably caused by systematic errors in the available gravity data for Scandinavia. This is confirmed by a new geoid computation at the Danish Geodetic Institute where the slope has disappeared. If this new solution is taken for the northern traverse section and the best solution for the central part, the rms discrepancy reduces to approximately + or - 0.2 m over 3000 km. Thus, a + or - 10 (exp 7) relative height accuracy seems to be achievable over long distances with the GPS/leveling and the gravimetric geoid calculation techniques, applied in this experiment.
Route Repetition and Route Reversal: Effects of Age and Encoding Method
Allison, Samantha; Head, Denise
2017-01-01
Previous research indicates age-related impairments in learning routes from a start location to a target destination. There is less research on age effects on the ability to reverse a learned path. The method used to learn routes may also influence performance. This study examined how encoding methods influence the ability of younger and older adults to recreate a route in a virtual reality environment in forward and reverse directions. Younger (n=50) and older (n=50) adults learned a route by either self-navigation through the virtual environment or through studying a map. At test, participants recreated the route in the forward and reverse directions. Older adults in the map study condition had greater difficulty learning the route in the forward direction compared to younger adults. Older adults who learned the route by self-navigation were less accurate in traversing the route in the reverse compared to forward direction after a delay. In contrast, for older adults who learned via map study there were no significant differences between forward and reverse directions. Results suggest that older adults may not as readily develop and retain a sufficiently flexible representation of the environment during self-navigation to support accurate route reversal. Thus, initially learning a route from a map may be more difficult for older adults, but may ultimately be beneficial in terms of better supporting the ability to return to a start location. PMID:28504535
Glimpse of Bagnold Dunes Edging Mount Sharp
2015-11-16
The dark band in the lower portion of this Martian scene is part of the "Bagnold Dunes" dune field lining the northwestern edge of Mount Sharp, inside Gale Crater. The view combines multiple images taken with the Mast Camera (Mastcam) on NASA's Curiosity Mars rover on Sept. 25, 2015, during the 1,115th Martian day, or sol, of Curiosity's work on Mars. The images are from Mastcam's right-eye camera, which has a telephoto lens. The view is toward south-southeast. Curiosity will visit examples of the Bagnold Dunes on the rover's route to higher layers of Mount Sharp. The informal name for the dune field is a tribute to British military engineer Ralph Bagnold (1896-1990), a pioneer in the study of how winds move sand particles of dunes on Earth. The dune field is evident as a dark band in orbital images of the area inside Gale Crater where Curiosity has been active since landing in 2012, such as a traverse map at PIA20162. Dunes are larger than wind-blown ripples of sand or dust that Curiosity and other rovers have visited previously. The scene is presented with a color adjustment that approximates white balancing, to resemble how the rocks and sand would appear under daytime lighting conditions on Earth. http://photojournal.jpl.nasa.gov/catalog/PIA19929
NASA Astrophysics Data System (ADS)
James, D.; Poppe, A.; Horanyi, M.
2008-12-01
The Venetia Burney Student Dust Counter (VSDC) on the New Horizons mission is a dust impact detector designed to map the interplanetary dust distribution along the trajectory of the spacecraft as it traverses our solar system. VSDC is the first student-built instrument on a deep space mission and is currently operated by a small group of undergraduate and graduate students at the Laboratory for Atmospheric and Space Physics (LASP), University of Colorado. VSDC is based on permanently polarized thin plastic film sensors that generate an electrical signal when a dust particle impacts them. The total surface area is about 0.1 square meters and the detection threshold is about 1 micron in radius. By the time of this meeting (12/2008), VSDC will have operated for about 500 days, and will have data covering an approximate distance of 1.2 to 11.0 AU from the Sun. In this talk, we will briefly review the VSDC instrument, including the in-flight calibrations and tests. We will report on the measured spatial and size distribution of interplanetary dust particles before and after the New Horizons encounter with Jupiter. These data will also be compared to earlier measurements by Ulysses and Galileo.
Dust Measurements On-board the New Horizons Mission
NASA Astrophysics Data System (ADS)
Poppe, A.; James, D.; Horanyi, M.
2007-12-01
The Venetia Burney Student Dust Counter (VSDC) on the New Horizons spacecraft was successfully commissioned on March 3, 2006 (DOY 2006/061). VSDC is a dust impact detector designed to map the dust distribution along the trajectory of the New Horizons spacecraft as it traverses our solar system. VSDC is the first student built instrument on a deep space mission and it is currently operated by a small group of undergraduate and graduate students at the Laboratory of Atmospheric and Space Physics (LASP), University of Colorado. By the time of this meeting (12/2007), VSDC will have operated for about 330 days, covering an approximate distance from 1.21 to 10 AU. VSDC is based on permanently polarized thin plastic film sensors that generate an electrical signal when an impacting dust particle penetrates them. The total surface area is about 0.1 square meters, and the detection threshold is about a micron in particle radius. In this talk we will briefly review the VSDC instrument. The in-flight tests and calibrations, as well as our initial science results will be discussed. We will report on the measured spatial and size distribution of interplanetary dust particles before and after the encounter with Jupiter. These measurements will be compared with earlier measurements by Ulysses, Galileo, and Cassini.
Mapping and localization for extraterrestrial robotic explorations
NASA Astrophysics Data System (ADS)
Xu, Fengliang
In the exploration of an extraterrestrial environment such as Mars, orbital data, such as high-resolution imagery Mars Orbital Camera-Narrow Angle (MOC-NA), laser ranging data Mars Orbital Laser Altimeter (MOLA), and multi-spectral imagery Thermal Emission Imaging System (THEMIS), play more and more important roles. However, these remote sensing techniques can never replace the role of landers and rovers, which can provide a close up and inside view. Similarly, orbital mapping can not compete with ground-level close-range mapping in resolution, precision, and speed. This dissertation addresses two tasks related to robotic extraterrestrial exploration: mapping and rover localization. Image registration is also discussed as an important aspect for both of them. Techniques from computer vision and photogrammetry are applied for automation and precision. Image registration is classified into three sub-categories: intra-stereo, inter-stereo, and cross-site, according to the relationship between stereo images. In the intra-stereo registration, which is the most fundamental sub-category, interest point-based registration and verification by parallax continuity in the principal direction are proposed. Two other techniques, inter-scanline search with constrained dynamic programming for far range matching and Markov Random Field (MRF) based registration for big terrain variation, are explored as possible improvements. Creating using rover ground images mainly involves the generation of Digital Terrain Model (DTM) and ortho-rectified map (orthomap). The first task is to derive the spatial distribution statistics from the first panorama and model the DTM with a dual polynomial model. This model is used for interpolation of the DTM, using Kriging in the close range and Triangular Irregular Network (TIN) in the far range. To generate a uniformly illuminated orthomap from the DTM, a least-squares-based automatic intensity balancing method is proposed. Finally a seamless orthomap is constructed by a split-and-merge technique: the mapped area is split or subdivided into small regions of image overlap, and then each small map piece was processed and all of the pieces are merged together to form a seamless map. Rover localization has three stages, all of which use a least-squares adjustment procedure: (1) an initial localization which is accomplished by adjustment over features common to rover images and orbital images, (2) an adjustment of image pointing angles at a single site through inter and intra-stereo tie points, and (3) an adjustment of the rover traverse through manual cross-site tie points. The first stage is based on adjustment of observation angles of features. The second stage and third stage are based on bundle-adjustment. In the third-stage an incremental adjustment method was proposed. Automation in rover localization includes automatic intra/inter-stereo tie point selection, computer-assisted cross-site tie point selection, and automatic verification of accuracy. (Abstract shortened by UMI.)
Problems With Deployment of Multi-Domained, Multi-Homed Mobile Networks
NASA Technical Reports Server (NTRS)
Ivancic, William D.
2008-01-01
This document describes numerous problems associated with deployment of multi-homed mobile platforms consisting of multiple networks and traversing large geographical areas. The purpose of this document is to provide insight to real-world deployment issues and provide information to groups that are addressing many issues related to multi-homing, policy-base routing, route optimization and mobile security - particularly those groups within the Internet Engineering Task Force.
Unmanned surface traverses of Mars and Moon: Science objectives, payloads, operations
NASA Technical Reports Server (NTRS)
Jaffe, L. D.; Choate, R.
1973-01-01
Science objectives and properties to be measured are outlined for long surface traverse missions on Mars and the Moon, with remotely-controlled roving vehicles. A series of candidate rover payloads is proposed for each planet, varying in weight, cost, purpose, and development needed. The smallest weighs 35 kg; the largest almost 300 kg. A high degree of internal control will be needed on the Mars rover, including the ability to carry out complex science sequences. Decision-making by humans in the Mars mission includes supervisory control of rover operations and selection of features and samples of geological and biological interest. For the lunar mission, less control on the rover and more on earth is appropriate. Science portions of the rover mission profile are outlined, with timelines and mileage breakdowns. Operational problem areas for Mars include control, communications, data storage, night operations, and the mission operations system. For the moon, science data storage on the rover would be unnecessary and control much simpler.
Lunar surface exploration using mobile robots
NASA Astrophysics Data System (ADS)
Nishida, Shin-Ichiro; Wakabayashi, Sachiko
2012-06-01
A lunar exploration architecture study is being carried out by space agencies. JAXA is carrying out research and development of a mobile robot (rover) to be deployed on the lunar surface for exploration and outpost construction. The main target areas for outpost construction and lunar exploration are mountainous zones. The moon's surface is covered by regolith. Achieving a steady traversal of such irregular terrain constitutes the major technical problem for rovers. A newly developed lightweight crawler mechanism can effectively traverse such irregular terrain because of its low contact force with the ground. This fact was determined on the basis of the mass and expected payload of the rover. This paper describes a plan for Japanese lunar surface exploration using mobile robots, and presents the results of testing and analysis needed in their development. This paper also gives an overview of the lunar exploration robot to be deployed in the SELENE follow-on mission, and the composition of its mobility, navigation, and control systems.
Planning for rover opportunistic science
NASA Technical Reports Server (NTRS)
Gaines, Daniel M.; Estlin, Tara; Forest, Fisher; Chouinard, Caroline; Castano, Rebecca; Anderson, Robert C.
2004-01-01
The Mars Exploration Rover Spirit recently set a record for the furthest distance traveled in a single sol on Mars. Future planetary exploration missions are expected to use even longer drives to position rovers in areas of high scientific interest. This increase provides the potential for a large rise in the number of new science collection opportunities as the rover traverses the Martian surface. In this paper, we describe the OASIS system, which provides autonomous capabilities for dynamically identifying and pursuing these science opportunities during longrange traverses. OASIS uses machine learning and planning and scheduling techniques to address this goal. Machine learning techniques are applied to analyze data as it is collected and quickly determine new science gods and priorities on these goals. Planning and scheduling techniques are used to alter the behavior of the rover so that new science measurements can be performed while still obeying resource and other mission constraints. We will introduce OASIS and describe how planning and scheduling algorithms support opportunistic science.
Image reconstruction from cone-beam projections with attenuation correction
NASA Astrophysics Data System (ADS)
Weng, Yi
1997-07-01
In single photon emission computered tomography (SPECT) imaging, photon attenuation within the body is a major factor contributing to the quantitative inaccuracy in measuring the distribution of radioactivity. Cone-beam SPECT provides improved sensitivity for imaging small organs. This thesis extends the results for 2D parallel- beam and fan-beam geometry to 3D parallel-beam and cone- beam geometries in order to derive filtered backprojection reconstruction algorithms for the 3D exponential parallel-beam transform and for the exponential cone-beam transform with sampling on a sphere. An exact inversion formula for the 3D exponential parallel-beam transform is obtained and is extended to the 3D exponential cone-beam transform. Sampling on a sphere is not useful clinically and current cone-beam tomography, with the focal point traversing a planar orbit, does not acquire sufficient data to give an accurate reconstruction. Thus a data acquisition method that obtains complete data for cone-beam SPECT by simultaneously rotating the gamma camera and translating the patient bed, so that cone-beam projections can be obtained with the focal point traversing a helix that surrounds the patient was developed. First, an implementation of Grangeat's algorithm for helical cone- beam projections was developed without attenuation correction. A fast new rebinning scheme was developed that uses all of the detected data to reconstruct the image and properly normalizes any multiply scanned data. In the case of attenuation no theorem analogous to Tuy's has been proven. We hypothesized that an artifact-free reconstruction could be obtained even if the cone-beam data are attenuated, provided the imaging orbit satisfies Tuy's condition and the exact attenuation map is known. Cone-beam emission data were acquired by using a circle- and-line and a helix orbit on a clinical SPECT system. An iterative conjugate gradient reconstruction algorithm was used to reconstruct projection data with a known attenuation map. The quantitative accuracy of the attenuation-corrected emission reconstruction was significantly improved.
Traversing psychological distance.
Liberman, Nira; Trope, Yaacov
2014-07-01
Traversing psychological distance involves going beyond direct experience, and includes planning, perspective taking, and contemplating counterfactuals. Consistent with this view, temporal, spatial, and social distances as well as hypotheticality are associated, affect each other, and are inferred from one another. Moreover, traversing all distances involves the use of abstraction, which we define as forming a belief about the substitutability for a specific purpose of subjectively distinct objects. Indeed, across many instances of both abstraction and psychological distancing, more abstract constructs are used for more distal objects. Here, we describe the implications of this relation for prediction, choice, communication, negotiation, and self-control. We ask whether traversing distance is a general mental ability and whether distance should replace expectancy in expected-utility theories. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Suarez, J. K. B.; Santiago, J. T.; Tablazon, J. P.; Dasallas, L. L.; Goting, P. G.; Lagmay, A. M. A.
2016-12-01
The Philippines, located in the Northwestern Pacific Typhoon gateway to Asia, is considered one of the most susceptible to tropical cyclone related hazards. One of the most disastrous effects of tropical cyclones is storm surge. With Metro Manila being a coastal area and the most populous region in the country, with approximately 12.8 million people residing in it, it is of great interest to determine the possibility of generating significant level of storm surge in the country's capital. The necessity to determine the storm surge susceptibility was brought upon by the effect of Typhoon Haiyan on eastern Visayas in 2013, where more than 6,000 people died and resulted to about 2.86 billion dollars' worth of damages. To achieve the objectives, the actual tracks and wind speed of historical typhoon (JMA data since 1951) was mapped for the Philippines. The simulated wind speed map shows that the maximum winds are mostly experienced on the eastern side of the country; with a considerable decrease in wind intensity as the typhoon reaches the western seaboard due to land surface. The Haiyan-strength wind speed is then applied to the actual historical typhoon tracks to determine the hypothetical values of wind speed as a typhoon with Haiyan intensity reached Metro Manila. Results show that, if a typhoon with a Haiyan-like intensity is to traverse tracks like those of Rita 1978, Collen 1992, Sybil 1995, Bebinca 2000 and Xangsane 2000, there is a huge possibility of generating storm surge height of 3.9 to 5.6 m in the western seaboard of Metro Manila, even after considering the diminishing effect of surface friction.
Statistical Algorithms for Designing Geophysical Surveys to Detect UXO Target Areas
DOE Office of Scientific and Technical Information (OSTI.GOV)
O'Brien, Robert F.; Carlson, Deborah K.; Gilbert, Richard O.
2005-07-29
The U.S. Department of Defense is in the process of assessing and remediating closed, transferred, and transferring military training ranges across the United States. Many of these sites have areas that are known to contain unexploded ordnance (UXO). Other sites or portions of sites are not expected to contain UXO, but some verification of this expectation using geophysical surveys is needed. Many sites are so large that it is often impractical and/or cost prohibitive to perform surveys over 100% of the site. In that case, it is particularly important to be explicit about the performance required of the survey. Thismore » article presents the statistical algorithms developed to support the design of geophysical surveys along transects (swaths) to find target areas (TAs) of anomalous geophysical readings that may indicate the presence of UXO. The algorithms described here determine 1) the spacing between transects that should be used for the surveys to achieve a specified probability of traversing the TA, 2) the probability of both traversing and detecting a TA of anomalous geophysical readings when the spatial density of anomalies within the TA is either uniform (unchanging over space) or has a bivariate normal distribution, and 3) the probability that a TA exists when it was not found by surveying along transects. These algorithms have been implemented in the Visual Sample Plan (VSP) software to develop cost-effective transect survey designs that meet performance objectives.« less
Statistical Algorithms for Designing Geophysical Surveys to Detect UXO Target Areas
DOE Office of Scientific and Technical Information (OSTI.GOV)
O'Brien, Robert F.; Carlson, Deborah K.; Gilbert, Richard O.
2005-07-28
The U.S. Department of Defense is in the process of assessing and remediating closed, transferred, and transferring military training ranges across the United States. Many of these sites have areas that are known to contain unexploded ordnance (UXO). Other sites or portions of sites are not expected to contain UXO, but some verification of this expectation using geophysical surveys is needed. Many sites are so large that it is often impractical and/or cost prohibitive to perform surveys over 100% of the site. In such cases, it is particularly important to be explicit about the performance required of the surveys. Thismore » article presents the statistical algorithms developed to support the design of geophysical surveys along transects (swaths) to find target areas (TAs) of anomalous geophysical readings that may indicate the presence of UXO. The algorithms described here determine (1) the spacing between transects that should be used for the surveys to achieve a specified probability of traversing the TA, (2) the probability of both traversing and detecting a TA of anomalous geophysical readings when the spatial density of anomalies within the TA is either uniform (unchanging over space) or has a bivariate normal distribution, and (3) the probability that a TA exists when it was not found by surveying along transects. These algorithms have been implemented in the Visual Sample Plan (VSP) software to develop cost-effective transect survey designs that meet performance objectives.« less
NASA Astrophysics Data System (ADS)
Hoque, M. A.; McArthur, J. M.; Sikdar, P. K.
2014-05-01
Pollution of groundwater in the Bengal Basin (Bangladesh and West Bengal, India) by arsenic (As) puts at risk the health of more than 100 million consumers. Using 1,580 borehole lithological logs and published hydrochemistry on 2,387 wells, it was predicted that low-As (<10 μg/L) groundwater exists, in palaeo-interfluvial aquifers of brown sand capped by a protective palaeosol, beneath at least 45,000 km2 of the Bengal Basin. The aquifers were predicted to be at a depth of as little as 25 m below ground level (mbgl), and typically no more than 50 mbgl. The predictions were confirmed along an east-west traverse 115 km in length (i.e. across half of Bangladesh) by drilling 28 new boreholes to 91-m depth to reveal subsurface sedimentology, and by mapping As distribution in groundwater. The aquifers identified occur at typically <40 mbgl and so are accessible with local drilling methods. A protective palaeosol that caps the palaeo-interfluvial aquifers prevents downward movement into them of As-polluted groundwater present in shallower palaeo-channel aquifers and ensures that the palaeo-interfluvial aquifers will yield low-As groundwater for the foreseeable future. Their use, in place of the shallower As-polluted palaeo-channel aquifers, would rapidly mitigate the health risks from consumption of As-polluted groundwater.
Automatic detection of sweep-meshable volumes
Tautges,; Timothy J. , White; David, R [Pittsburgh, PA
2006-05-23
A method of and software for automatically determining whether a mesh can be generated by sweeping for a representation of a geometric solid comprising: classifying surface mesh schemes for surfaces of the representation locally using surface vertex types; grouping mappable and submappable surfaces of the representation into chains; computing volume edge types for the representation; recursively traversing surfaces of the representation and grouping the surfaces into source, target, and linking surface lists; and checking traversal direction when traversing onto linking surfaces.
Kodaira, Satoshi; Konishi, Teruaki; Kobayashi, Alisa; Maeda, Takeshi; Ahmad, Tengku Ahbrizal Farizal Tengku; Yang, Gen; Akselrod, Mark S.; Furusawa, Yoshiya; Uchihori, Yukio
2015-01-01
Abstract The geometric locations of ion traversals in mammalian cells constitute important information in the study of heavy ion-induced biological effect. Single ion traversal through a cellular nucleus produces complex and massive DNA damage at a nanometer level, leading to cell inactivation, mutations and transformation. We present a novel approach that uses a fluorescent nuclear track detector (FNTD) for the simultaneous detection of the geometrical images of ion traversals and DNA damage in single cells using confocal microscopy. HT1080 or HT1080–53BP1-GFP cells were cultured on the surface of a FNTD and exposed to 5.1-MeV/n neon ions. The positions of the ion traversals were obtained as fluorescent images of a FNTD. Localized DNA damage in cells was identified as fluorescent spots of γ-H2AX or 53BP1-GFP. These track images and images of damaged DNA were obtained in a short time using a confocal laser scanning microscope. The geometrical distribution of DNA damage indicated by fluorescent γ-H2AX spots in fixed cells or fluorescent 53BP1-GFP spots in living cells was found to correlate well with the distribution of the ion traversals. This method will be useful for evaluating the number of ion hits on individual cells, not only for micro-beam but also for random-beam experiments. PMID:25324538
Topographic control of sorted circle morphology on Svalbard
NASA Astrophysics Data System (ADS)
Voigt, Joana; Hauber, Ernst; Reiss, Dennis; Hiesinger, Harald; Johnsson, Andreas; van Gasselt, Stephan; Balme, Matt; Head, Jim; de Verra, Jean-Pierre; Steinbrügge, Gregor; Jaumann, Ralf
2015-04-01
Patterned ground is a typical phenomenon in polar, subpolar and alpine regions [1]. As it is commonly (but not necessarily!) related to freeze-thaw cycles, its presence on Mars could possibly point to locations and periods where and when liquid water existed in the recent past [2]. Sorted circles are a class of patterned ground that was tentatively identified in Elysium Planitia (Mars) [3], but this interpretation has been challenged on the basis of physical considerations [4]. Without direct access to potential patterned ground on Mars, the analysis of terrestrial analogues can inform the interpretation of Martian landforms. Svalbard (Norway) offers a wide variety of permafrost features that are morphologically analogous to Martian cold-climate landforms [5]. It hosts some of the best examples of sorted circles on Earth, which are located on the westernmost tip of Brøgger peninsula, on a broad strand flat that is characterized by a series of postglacial beach ridges [6]. Here we report on our analysis of sorted circle morphology (especially their plan-view shape, i.e. their "roundness" or ellipticity) and its correlation with local topography (slopes, curvature). Sorted circle morphology was determined from HRSC-AX images (for details on the flight campaign and image properties see ref [5]) and through field work. Topographic information comes from a 50 cm gridded DEM derived from HRSC-AX stereo images. We measured sorted circle morphology (ellipticity, azimuth of major axis) along a WNW-ESE traverse that runs from the inland towards the sea and is oriented perpendicular to the local beach ridge trend. Selected areas with homogeneous sorted circle appearance were visually mapped, and compared to the average slope, aspect, and the calculated topographic wetness index (TWI). Furthermore the whole traverse was classified into four different morphologies of the sorted patterned ground (sorted circles, sorted "ellipses", sorted nets and areas without patterned ground). For these morphologies, we also measured the slope, aspect and TWI to correlate the topographical parameters with the geomorphological characteristics of the patterned ground, and with predictions from modeling [7]. Our results confirm that the dependence of morphology on topography of sorted circles can be measured using a combination of plan-view and topographic remote sensing data. Thus, as the same quality of data is available on Mars, these same measurements could be made there in order to test whether the circle morphology depends on the local relief patterns in the same ways as in our terrestrial study. A positive result would argue that the Martian features may have formed in the same way (freeze-thaw) as the terrestrial ones. [1] Washburn, A.L. (1956) Geol. Soc. Amer. Bull. 67, 823-866. [2] Balme et al. (2013) Prog. Phys. Geog. 37, 289-324. [3] Balme et al. (2009) Icarus 200, 30-38. [4] Kreslavsky, M.A., Head, J.W. (2014) LPSC 45, abstract 2715. [5] Hauber et al. (2011) GSA Spec. Paper 483, 177-201. [6] Tolgensbakk, J., Sollid, J.L. (1987) Kvadehuksletta, Geomorfologi og Kvartærgeologi (geomorphological map; scale 1:10,000), Universitet i Oslo. [7] Kessler, M.A., Werner, B.T. (2003) Science 299, 380-383.
Interpreting Radar View near Mars' South Pole, Orbit 1334
NASA Technical Reports Server (NTRS)
2006-01-01
A radargram from the Shallow Subsurface Radar instrument (SHARAD) on NASA's Mars Reconnaissance Orbiter is shown in the upper-right panel and reveals detailed structure in the polar layered deposits of the south pole of Mars. The sounding radar collected the data presented here during orbit 1334 of the mission, on Nov. 8, 2006. The horizontal scale in the radargram is distance along the ground track. It can be referenced to the ground track map shown in the lower right. The radar traversed from about 75 to 85 degrees south latitude, or about 590 kilometers (370 miles). The ground track map shows elevation measured by the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor orbiter. Green indicates low elevation; reddish-white indicates higher elevation. The traverse proceeds up onto a plateau formed by the layers. The vertical scale on the radargram is time delay of the radar signals reflected back to Mars Reconnaissance Orbiter from the surface and subsurface. For reference, using an assumed velocity of the radar waves in the subsurface, time is converted to depth below the surface at one place: about 1,500 meters (5,000 feet) to one of the deeper subsurface reflectors. The color scale varies from black for weak reflections to white for strong reflections. The middle panel shows mapping of the major subsurface reflectors, some of which can be traced for a distance of 100 kilometers (60 miles) or more. The layers are not all horizontal and the reflectors are not always parallel to one another. Some of this is due to variations in surface elevation, which produce differing velocity path lengths for different reflector depths. However, some of this behavior is due to spatial variations in the deposition and removal of material in the layered deposits, a result of the recent climate history of Mars. The Shallow Subsurface Radar was provided by the Italian Space Agency (ASI). Its operations are led by the University of Rome and its data are analyzed by a joint U.S.-Italian science team. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter for the NASA Science Mission Directorate, Washington.Rock formations in the Colorado Plateau of Southeastern Utah and Northern Arizona
Longwell, C.R.; Miser, H.D.; Moore, R.C.; Bryan, Kirk; Paige, Sidney
1925-01-01
The field work of which this report is a record was done in the summer and fall of 1921 by members of the United States Geological Survey. A project to build a large storage dam at Lees Ferry, on Colorado River in northern Arizona, called for a detailed topographic survey of the area covered by the project, for the purpose of determining the capacity of the reservoir. This work was undertaken by the United States Geological Survey in cooperation with the Southern California Edison Co. Three surveying parties were sent to the field, each accompanied by a geologist, whose specific duty was to study and report on the rock formations within the area to be flooded. One topographic party, under A. T. Fowler, which started at Lees Ferry and worked up stream in Arizona, was accompanied by Kirk Bryan. Another party, under K. W. Trimble, which started near Bluff and worked down the San Juan and thence down the Colorado, was accompanied by H. D. Miser. The third party, under W. R. Chenoweth, worked from Fremont River to the Waterpocket Fold and then returned to Green River, Utah, and traversed Cataract Canyon during the period of low water. C. R. Longwell was with this party until September, when his place was taken by Sidney Paige. Mr. Paige, in company with the Kolb brothers, E. C. La Rue, and Henry Ranch, left the Chenoweth party after Cataract Canyon had been surveyed and rowed down the Colorado to the mouth of the San Juan, where they were joined by Mr. Miser. Then they took a hurried trip by boat down the Colorado to Lees Ferry, making a few short stops and visiting the famous Rainbow Bridge. Thus the geology of the canyons of Colorado and San Juan rivers and of the lower parts of tributary canyons was examined continuously, and reconnaissance work was done in the country back from the rivers. At the same time a fourth party, under R. C. Moore, was mapping parts of Kane, Garfield, and Wayne counties, Utah, to determine whether oil might be found there. The present paper includes brief descriptions of the rocks of the regions traversed, detailed geologic sections, and columnar sections measured not only by the geologists who accompanied these parties but by other geologists who have worked in the same regions or in adjoining regions. The positions of the columnar sections measured and many of the other sections are shown on Figure 1.
A reactive system for open terrain navigation: Performance and limitations
NASA Technical Reports Server (NTRS)
Langer, D.; Rosenblatt, J.; Hebert, M.
1994-01-01
We describe a core system for autonomous navigation in outdoor natural terrain. The system consists of three parts: a perception module which processes range images to identify untraversable regions of the terrain, a local map management module which maintains a representation of the environment in the vicinity of the vehicle, and a planning module which issues commands to the vehicle controller. Our approach is to use the concept of 'early traversability evaluation', and on the use of reactive planning for generating commands to drive the vehicle. We argue that our approach leads to a robust and efficient navigation system. We illustrate our approach by an experiment in which a vehicle travelled autonomously for one kilometer through unmapped cross-country terrain.
Total Solar Eclipse of 2008 August 01
NASA Technical Reports Server (NTRS)
Espenak, F.; Anderson, J.
2007-01-01
On 2008 August 01, a total eclipse of the Sun is visible from within a narrow corridor that traverses half the Earth. The path of the Moon's umbral shadow begins in northern Canada and extends across Greenland, the Arctic, central Russia, Mongolia, and China. A partial eclipse is seen within the much broader path of the Moon's penumbral shadow, which includes northeastern North America, most of Europe and Asia. Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for 308 cities, maps of the eclipse path, weather prospects, the lunar limb profile and the sky during totality. Information on safe eclipse viewing and eclipse photography is included.
Gray, J.E.; Coolbaugh, M.F.
1994-01-01
Geologic studies during recent open-pit mining at Summitville, Colorado, have provided new information on an epithermal acid sulfate Au-Ag-Cu deposit formed in a volcanic dome. Geologic mapping, geochemical studies of whole-rock samples from blast holes, and geologic and geochemical traverse studies refine the details of the evolution of the Summitville deposit. Six distinct events followed emplacement of the quartz latite volcanic dome and define the development of the Summitville deposit: 1) an early stage of acid sulfate alteration, 2) subsequent Cu sulfide and gold mineralization, 3) widespread hydrothermal brecciation, 4) volumetrically minor, base metal sulfide-bearing barite veining, 5) volumetrically minor, kaolinite matrix brecciation, and finally, 6) supergene oxidation. -from Authors
Geologic map of the Snoqualmie Pass 30 x 60 minute quadrangle, Washington
Tabor, R.W.; Frizzell, V.A.; Booth, D.B.; Waitt, R.B.
2000-01-01
The Snoqualmie Pass quadrangle lies at the north edge of a Tertiary volcanic and sedimentary cover, where the regional structural uplift to the north elevated the older rocks to erosional levels. Much of the quadrangle is underlain by folded Eocene volcanic rocks and fluvial deposts of an extensional event, and these rocks are overlain by Cascade arc volcanic rocks: mildly deformed Oligocene-Miocene rocks and undeformed younger volcanic rocks. Melanges of Paleozoic and Mesozoic rocks are exposed in structural highs in the northern part of the quadrangle. The quadrangle is traversed north to south by the Straight Creek Fault, and the probably partially coincident Darringon-Devils Mountain Fault. A rich Quaternary stratigraphy reveals events of the Frazer glaciation.
DMSP F7 observations of a substorm field-aligned current
NASA Technical Reports Server (NTRS)
Lopez, R. E.; Spence, H. E.; Meng, C.-I.
1991-01-01
Observations are described of a substorm field-aligned current (FAC) system traversed by the DMSP F7 spacecraft just after 0300 UT on April 25, 1985. It is shown that the substorm FAC portion of the current system was located equatorward of the boundary between open and closed field lines. The equatorward boundary of the substorm FAC into the magnetotail was mapped using the Tsyganenko (1987) model, showing that the boundary corresponds to 6.9 earth radii. The result is consistent with the suggestion of Akasofu (1972) and Lopez and Lui (1990) that the region of substorm initiation lies relatively close to the earth and the concept that an essential feature of substorms is the disruption and diversion of the near-earth current sheet.
Documentation of Apollo 15 samples
NASA Technical Reports Server (NTRS)
Sutton, R. L.; Hait, M. H.; Larson, K. B.; Swann, G. A.; Reed, V. S.; Schaber, G. G.
1972-01-01
A catalog is presented of the documentation of Apollo 15 samples using photographs and verbal descriptions returned from the lunar surface. Almost all of the Apollo 15 samples were correlated with lunar surface photographs, descriptions, and traverse locations. Where possible, the lunar orientations of rock samples were reconstructed in the lunar receiving laboratory, using a collimated light source to reproduce illumination and shadow characteristics of the same samples shown in lunar photographs. In several cases, samples were not recognized in lunar surface photographs, and their approximate locations are known only by association with numbered sample bags used during their collection. Tables, photographs, and maps included in this report are designed to aid in the understanding of the lunar setting of the Apollo 15 samples.
Acute Resuscitation and Transfer Management of Burned and Electrically Injured Patients,
1994-01-01
patient. When all visible chemical the hospital and is usually provided by is removed , copious irrigation with water local fire or emergency medical... remove the victim chemicals, especially alkaline agents, may from the fire environment to a safe area. continue to irritate for hours, irrigation Once...veins and then sutured in place. vical spine if injury is suspected), and Cannulas traversing burned skin are ac- Exposure ( removal of all clothing and
Infantry Weapons Test Methodology Study. Volume 3. Light Machine Gun Test Methodology
1972-06-01
Trajjectnry and marionim ordiwate. to the target increases beyond 500 meters, the beaten zone will become shorter and wider. When fires are de - livered into...traversing amount of elevation change is de - handwheel. To insure adequate tar- termined by the slope of the terrain get coverage, a burst is fired after and...to the traversing handwheel. The 6-mii increments on the traversing amount of elevation change Is de - handwheel. To insure adequate tar- termined by
NASA Astrophysics Data System (ADS)
Hess Webber, Shea A.; Thompson, Barbara J.; Kwon, Ryun Young; Ireland, Jack
2018-01-01
An improved understanding of the kinematic properties of CMEs and CME-associated phenomena has several impacts: 1) a less ambiguous method of mapping propagating structures into their inner coronal manifestations, 2) a clearer view of the relationship between the “main” CME and CME-associated brightenings, and 3) an improved identification of the heliospheric sources of shocks, Type II bursts, and SEPs. We present the results of a mapping technique that facilitates the separation of CMEs and CME-associated brightenings (such as shocks) from background corona. The Time Convolution Mapping Method (TCMM) segments coronagraph data to identify the time history of coronal evolution, the advantage being that the spatiotemporal evolution profiles allow users to separate features with different propagation characteristics. For example, separating “main” CME mass from CME-associated brightenings or shocks is a well-known obstacle, which the TCMM aids in differentiating. A TCMM CME map is made by first recording the maximum value each individual pixel in the image reaches during the traversal of the CME. Then the maximum value is convolved with an index to indicate the time that the pixel reached that value. The TCMM user is then able to identify continuous “kinematic profiles,” indicating related kinematic behavior, and also identify breaks in the profiles that indicate a discontinuity in kinematic history (i.e. different structures or different propagation characteristics). The maps obtained from multiple spacecraft viewpoints (i.e., STEREO and SOHO) can then be fit with advanced structural models to obtain the 3D properties of the evolving phenomena. We will also comment on the TCMM's further applicability toward the tracking of prominences, coronal hole boundaries and coronal cavities.
Combined EDL-Mobility Planning for Planetary Missions
NASA Technical Reports Server (NTRS)
Kuwata, Yoshiaki; Balaram, Bob
2011-01-01
This paper presents an analysis framework for planetary missions that have coupled mobility and EDL (Entry-Descent-Landing) systems. Traditional systems engineering approaches to mobility missions such as MERs (Mars Exploration Rovers) and MSL (Mars Science Laboratory) independently study the EDL system and the mobility system, and does not perform explicit trade-off between them or risk minimization of the overall system. A major challenge is that EDL operation is inherently uncertain and its analysis results such as landing footprint are described using PDF (Probability Density Function). The proposed approach first builds a mobility cost-to-go map that encodes the driving cost of any point on the map to a science target location. The cost could include variety of metrics such as traverse distance, time, wheel rotation on soft soil, and closeness to hazards. It then convolves the mobility cost-to-go map with the landing PDF given by the EDL system, which provides a histogram of driving cost, which can be used to evaluate the overall risk of the mission. By capturing the coupling between EDL and mobility explicitly, this analysis framework enables quantitative tradeoff between EDL and mobility system performance, as well as the characterization of risks in a statistical way. The simulation results are presented with a realistic Mars terrain data
Improving Our Understanding of the 3D Coronal Evolution of CME Propagation
NASA Astrophysics Data System (ADS)
Hess Webber, Shea A.; Thompson, Barbara J.; Ireland, Jack; Kwon, Ryun Young
2017-08-01
An improved understanding of the kinematic properties of CMEs and CME-associated phenomena has several impacts: 1) a less ambiguous method of mapping propagating structures into their inner coronal manifestations, 2) a clearer view of the relationship between the “main” CME and CME-associated brightenings, and 3) an improved identification of the heliospheric sources of shocks, Type II bursts, and SEPs. We present the results of a mapping technique that facilitates the separation of CMEs and CME-associated brightenings (such as shocks) from background corona. The Time Convolution Mapping Method (TCMM) segments coronagraph data to identify the time history of coronal evolution, the advantage being that the spatiotemporal evolution profiles allow users to separate features with different propagation characteristics. For example, separating “main” CME mass from CME-associated brightenings or shocks is a well-known obstacle, which the TCMM aids in differentiating. A TCMM CME map is made by first recording the maximum value each individual pixel in the image reaches during the traversal of the CME. Then the maximum value is convolved with an index to indicate the time that the pixel reached that value. The TCMM user is then able to identify continuous “kinematic profiles,” indicating related kinematic behavior, and also identify breaks in the profiles that indicate a discontinuity in kinematic history (i.e. different structures or different propagation characteristics). The maps obtained from multiple spacecraft viewpoints (i.e., STEREO and SOHO) can then be fit with advanced structural models to obtain the 3D properties of the evolving phenomena.
SHUTTLE IMAGING RADAR PROVIDES FRAMEWORK FOR SUBSURFACE GEOLOGIC EXPLORATION IN EGYPT AND SUDAN.
Breed, Carol S.; McCauley, John F.; Schaber, Gerald G.
1984-01-01
Shuttle Imaging Radar provides a pictorial framework to guide exploration for mineral resources (potential placers), groundwater sources, and prehistoric archaeological sites in the Western Desert of Egypt and Sudan. Documented penetration by the SIR-A signal of dry surficial sediment to depths of a meter or more revealed bedrock geologic features and networks of former stream valleys otherwise concealed beneath windblown sand, alluvium, and colluvial deposits. 'Radar units' mapped on SIR-A images according to relative brightness and degree of mottling correspond to subsurface geologic and topographic features identified in more than 50 test pits. Petrologic examination of pit samples confirms that a variety of depositional environments existed in this now hyper-arid region before it was mantled by windblown sand sheets and dunes. Wet sand was discovered in two buried valleys shown on the radar images and located in the field with the aid of co-registered maps and Landsat images, and a satellite navigation device. Buried valleys whose streams once traversed mineralized zones are potential sites of placers (gold, tin).
A scale-free systems theory of motivation and addiction.
Chambers, R Andrew; Bickel, Warren K; Potenza, Marc N
2007-01-01
Scale-free organizations, characterized by uneven distributions of linkages between nodal elements, describe the structure and function of many life-based complex systems developing under evolutionary pressures. We explore motivated behavior as a scale-free map toward a comprehensive translational theory of addiction. Motivational and behavioral repertoires are reframed as link and nodal element sets, respectively, comprising a scale-free structure. These sets are generated by semi-independent information-processing streams within cortical-striatal circuits that cooperatively provide decision-making and sequential processing functions necessary for traversing maps of motivational links connecting behavioral nodes. Dopamine modulation of cortical-striatal plasticity serves a central-hierarchical mechanism for survival-adaptive sculpting and development of motivational-behavioral repertoires by guiding a scale-free design. Drug-induced dopamine activity promotes drug taking as a highly connected behavioral hub at the expense of natural-adaptive motivational links and behavioral nodes. Conceptualizing addiction as pathological alteration of scale-free motivational-behavioral repertoires unifies neurobiological, neurocomputational and behavioral research while addressing addiction vulnerability in adolescence and psychiatric illness. This model may inform integrative research in defining more effective prevention and treatment strategies for addiction.
Construction of a general human chromosome jumping library, with application to cystic fibrosis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Collins, F.S.; Drumm, M.L.; Cole, J.L.
1987-02-27
In many genetic disorders, the responsible gene and its protein product are unknown. The technique known as reverse genetics, in which chromosomal map positions and genetically linked DNA markers are used to identify and clone such genes, is complicated by the fact that the molecular distances from the closest DNA markers to the gene itself are often too large to traverse by standard cloning techniques. To address this situation, a general human chromosome jumping library was constructed that allows the cloning of DNA sequences approximately 100 kilobases away from any starting point in genomic DNA. As an illustration of itsmore » usefulness, this library was searched for a jumping clone, starting at the met oncogene, which is a marker tightly linked to the cystic fibrosis gene that is located on human chromosome 7. Mapping of the new genomic fragment by pulsed field gel electrophoresis confirmed that it resides on chromosome 7 within 240 kilobases downstream of the met gene. The use of chromosome jumping should be applicable to any genetic locus for which a closely linked DNA marker is available.« less
Persistent homology and non-Gaussianity
NASA Astrophysics Data System (ADS)
Cole, Alex; Shiu, Gary
2018-03-01
In this paper, we introduce the topological persistence diagram as a statistic for Cosmic Microwave Background (CMB) temperature anisotropy maps. A central concept in 'Topological Data Analysis' (TDA), the idea of persistence is to represent a data set by a family of topological spaces. One then examines how long topological features 'persist' as the family of spaces is traversed. We compute persistence diagrams for simulated CMB temperature anisotropy maps featuring various levels of primordial non-Gaussianity of local type. Postponing the analysis of observational effects, we show that persistence diagrams are more sensitive to local non-Gaussianity than previous topological statistics including the genus and Betti number curves, and can constrain Δ fNLloc= 35.8 at the 68% confidence level on the simulation set, compared to Δ fNLloc= 60.6 for the Betti number curves. Given the resolution of our simulations, we expect applying persistence diagrams to observational data will give constraints competitive with those of the Minkowski Functionals. This is the first in a series of papers where we plan to apply TDA to different shapes of non-Gaussianity in the CMB and Large Scale Structure.
Semi-autonomous exploration of multi-floor buildings with a legged robot
NASA Astrophysics Data System (ADS)
Wenger, Garrett J.; Johnson, Aaron M.; Taylor, Camillo J.; Koditschek, Daniel E.
2015-05-01
This paper presents preliminary results of a semi-autonomous building exploration behavior using the hexapedal robot RHex. Stairwells are used in virtually all multi-floor buildings, and so in order for a mobile robot to effectively explore, map, clear, monitor, or patrol such buildings it must be able to ascend and descend stairwells. However most conventional mobile robots based on a wheeled platform are unable to traverse stairwells, motivating use of the more mobile legged machine. This semi-autonomous behavior uses a human driver to provide steering input to the robot, as would be the case in, e.g., a tele-operated building exploration mission. The gait selection and transitions between the walking and stair climbing gaits are entirely autonomous. This implementation uses an RGBD camera for stair acquisition, which offers several advantages over a previously documented detector based on a laser range finder, including significantly reduced acquisition time. The sensor package used here also allows for considerable expansion of this behavior. For example, complete automation of the building exploration task driven by a mapping algorithm and higher level planner is presently under development.
A Scale-Free Systems Theory of Motivation and Addiction
Bickel, Warren K.; Potenza, Marc N.
2007-01-01
Scale-free organizations, characterized by uneven distributions of linkages between nodal elements, describe the structure and function of many life-based complex systems developing under evolutionary pressures. We explore motivated behavior as a scale-free map toward a comprehensive translational theory of addiction. Motivational and behavioral repertoires are reframed as link and nodal element sets, respectively, comprising a scale-free structure. These sets are generated by semi-independent information-processing streams within cortical-striatal circuits that cooperatively provide decision-making and sequential processing functions necessary for traversing maps of motivational links connecting behavioral nodes. Dopamine modulation of cortical-striatal plasticity serves a central-hierarchical mechanism for survival-adaptive sculpting and development of motivational-behavioral repertoires by guiding a scale-free design. Drug-induced dopamine activity promotes drug-taking as a highly connected behavioral hub at the expense of natural-adaptive motivational links and behavioral nodes. Conceptualizing addiction as pathological alteration of scale-free motivational-behavioral repertoires unifies neurobiological, neurocomputational and behavioral research while addressing addiction vulnerability in adolescence and psychiatric illness. This model may inform integrative research in defining more effective prevention and treatment strategies for addiction. PMID:17574673
Machine learning challenges in Mars rover traverse science
NASA Technical Reports Server (NTRS)
Castano, R.; Judd, M.; Anderson, R. C.; Estlin, T.
2003-01-01
The successful implementation of machine learning in autonomous rover traverse science requires addressing challenges that range from the analytical technical realm, to the fuzzy, philosophical domain of entrenched belief systems within scientists and mission managers.
Tunneling and traversal of ultracold three-level atoms through vacuum-induced potentials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Badshah, Fazal; Irfan, Muhammad; Qamar, Shahid
2011-09-15
The passage of ultracold three-level atoms through the potential induced by the vacuum cavity mode is discussed using cascade atomic configuration. We study the tunneling or traversal time of the ultracold atoms via a bimodal high-Q cavity. It is found that the phase time, which may be considered as a measure for the time required to traverse the cavity, exhibits superclassical and subclassical behaviors. Further, the dark states and interference effects in cascade atomic configuration may influence the passage time of the atom through the cavity.
Muller, George; Perkins, Casey J.; Lancaster, Mary J.; MacDonald, Douglas G.; Clements, Samuel L.; Hutton, William J.; Patrick, Scott W.; Key, Bradley Robert
2015-07-28
Computer-implemented security evaluation methods, security evaluation systems, and articles of manufacture are described. According to one aspect, a computer-implemented security evaluation method includes accessing information regarding a physical architecture and a cyber architecture of a facility, building a model of the facility comprising a plurality of physical areas of the physical architecture, a plurality of cyber areas of the cyber architecture, and a plurality of pathways between the physical areas and the cyber areas, identifying a target within the facility, executing the model a plurality of times to simulate a plurality of attacks against the target by an adversary traversing at least one of the areas in the physical domain and at least one of the areas in the cyber domain, and using results of the executing, providing information regarding a security risk of the facility with respect to the target.
Planetary Cartography and Mapping: where we are Today, and where we are Heading For?
NASA Astrophysics Data System (ADS)
Naß, A.; Di, K.; Elgner, S.; van Gasselt, S.; Hare, T.; Hargitai, H.; Karachevtseva, I.; Kersten, E.; Manaud, N.; Roatsch, T.; Rossi, A. P.; Skinner, J., Jr.; Wählisch, M.
2017-07-01
Planetary Cartography does not only provides the basis to support planning (e.g., landing-site selection, orbital observations, traverse planning) and to facilitate mission conduct during the lifetime of a mission (e.g., observation tracking and hazard avoidance). It also provides the means to create science products after successful termination of a planetary mission by distilling data into maps. After a mission's lifetime, data and higher level products like mosaics and digital terrain models (DTMs) are stored in archives - and eventually into maps and higher-level data products - to form a basis for research and for new scientific and engineering studies. The complexity of such tasks increases with every new dataset that has been put on this stack of information, and in the same way as the complexity of autonomous probes increases, also tools that support these challenges require new levels of sophistication. In planetary science, cartography and mapping have a history dating back to the roots of telescopic space exploration and are now facing new technological and organizational challenges with the rise of new missions, new global initiatives, organizations and opening research markets. The focus of this contribution is to summarize recent activities in Planetary Cartography, highlighting current issues the community is facing to derive the future opportunities in this field. By this we would like to invite cartographers/researchers to join this community and to start thinking about how we can jointly solve some of these challenges.
Toward Autonomous Multi-floor Exploration: Ascending Stairway Localization and Modeling
2013-03-01
robots have traditionally been restricted to single floors of a building or outdoor areas free of abrupt elevation changes such as curbs and stairs ...solution to this problem and is motivated by the rich potential of an autonomous ground robot that can climb stairs while exploring a multi-floor...parameters of the stairways, the robot could plan a path that traverses the stairs in order to explore the frontier at other elevations that were previously
Area 51: How do Acanthamoeba invade the central nervous system?
Siddiqui, Ruqaiyyah; Emes, Richard; Elsheikha, Hany; Khan, Naveed Ahmed
2011-05-01
Acanthamoeba granulomatous encephalitis generally develops as a result of haematogenous spread, but it is unclear how circulating amoebae enter the central nervous system (CNS) and cause inflammation. At present, the mechanisms which Acanthamoeba use to invade this incredibly well-protected area of the CNS and produce infection are not well understood. In this paper, we propose two key virulence factors: mannose-binding protein and extracellular serine proteases as key players in Acanthamoeba traversal of the blood-brain barrier leading to neuronal injury. Both molecules should provide excellent opportunities as potential targets in the rational development of therapeutic interventions against Acanthamoeba encephalitis. Copyright © 2011 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Tunstel, E.; Howard, A.; Edwards, D.; Carlson, A.
2001-01-01
This paper presents a technique for learning to assess terrain traversability for outdoor mobile robot navigation using human-embedded logic and real-time perception of terrain features extracted from image data.
Time of travel of the Flint River, Utah Dam to highway M-13, Michigan, August 4-8, 1981
Cummings, T. Ray; Miller, John B.
1982-01-01
Tracing of rhodamine WT dye has provided time-of-travel data for waste-load allocation studies of a 42.8-mile reach of the Flint River at low flow. A discharge equaled or exceeded about 90 percent of the time was measured at Grand Traverse Street in Flint before dye injection. Dye was injected at two locations in Flint--at Utah Dam and at Grand Traverse Street, From Utah Dam to Grand Traverse Street, the mean velocity of flow was about 0.1 foot per second; time-of-travel was 35.3 hours. From Grand Traverse Street to Highway M-13, mean velocity was about 0.7 foot per second; time-of-travel was 78.8 hours. Time-of-travel for the reach between Utah Dam and Highway M-13 was thus 114 hours.
NASA Technical Reports Server (NTRS)
Bentley, Charles
2012-01-01
Dr Charles Bentley is the A.P. Crary Professor Emeritus of Geophysics, Department of Geology and Geophysics, University of Wisconsin-Madison. Dr. Bentley joined the Arctic Institute of North America in 1956 to participate in International Geophysical Year (IGY)-related activities in the Antarctic. He wintered over consecutively in 1957 and 1958 at Byrd Station, a station in the interior of West Antarctica that housed 24 men each winter - 12 Navy support people and 12 civilian scientists/technicians. During the austral summers, he also participated in over-snow traverses, first as co-leader, then leader (the other coleader went home after the first year). These traverses consisted of six men and three vehicles, and lasted several months. These traverses covered more than 1609 kilometers (1000 miles) of largely unmapped and unphotographed terrain. During these traverses, connections to Byrd Station were by radio (daily, when the transmission conditions were good enough) and roughly every 2 weeks by resupply flight.
Footprint traversal by adenosine-triphosphate-dependent chromatin remodeler motor.
Garai, Ashok; Mani, Jesrael; Chowdhury, Debashish
2012-04-01
Adenosine-triphosphate (ATP)-dependent chromatin remodeling enzymes (CREs) are biomolecular motors in eukaryotic cells. These are driven by a chemical fuel, namely, ATP. CREs actively participate in many cellular processes that require accessibility of specific segments of DNA which are packaged as chromatin. The basic unit of chromatin is a nucleosome where 146 bp ∼ 50 nm of a double-stranded DNA (dsDNA) is wrapped around a spool formed by histone proteins. The helical path of histone-DNA contact on a nucleosome is also called "footprint." We investigate the mechanism of footprint traversal by a CRE that translocates along the dsDNA. Our two-state model of a CRE captures effectively two distinct chemical (or conformational) states in the mechanochemical cycle of each ATP-dependent CRE. We calculate the mean time of traversal. Our predictions on the ATP dependence of the mean traversal time can be tested by carrying out in vitro experiments on mononucleosomes.
Queen Maud Land Traverses: Surface Glaciology (Invited)
NASA Astrophysics Data System (ADS)
Cameron, R. L.
2009-12-01
One of the main tasks of a glaciologist is to determine the mass budget of a glacier; and snow accumulation is the first part of the equation. To do this, a great number of snow pits must be dug to analyze the stratigraphy. A. P. Crary once said “to be a glaciologist one should first of all love to dig snow pits.” Seventy-five snow pits were dug on the SPQMLT traverses. Several experienced glaciologists had difficulty in interpreting the stratigraphic sequences in these pits. Irregular layering, caused by uneven deposition and subsequent erosion, suggested that some of the layers could be missing. However, the fallout of artificial radioactive nuclides released by the first large thermonuclear bomb test, on March 1, 1954, at Castle Bravo on Bikini Atoll, Marshall Islands, produced a datum horizon over the Antarctic ice sheet. This horizon is the summer of 1954-55 and provides the basis for measuring the average accumulation since 1955. Accumulation varied from 6.7 ± 0.2 g cm-2 yr-1 at South Pole Station to a low of 0.6 ± 0.2 g cm-2 yr-1 in a pit on the second leg of SPQMLT 2. The average accumulation along the entire traverse route was 3.7 g cm-2 yr-1. Temperatures at ten meters (considered an approximate mean annual air temperature) varied from -58.4 degrees Centigrade at Plateau Station (elevation 3620 meters) to -38 degrees Centigrade at the terminus of SPQMLT 3 (elevation 2310 meters). The condition of the ice sheet surface varied considerably. Some surface was quite hard and easy to traverse; while other areas that were smooth and soft were troublesome enough to bog down vehicles and sleds. Sastrugi were sporadic with some as high as a meter. A large crevasse field forced a slight change in course toward the end of the first leg of SPQMLT 2. There the ice thickness changed dramatically from 3060 meters to 1852 meters. At the time the geophysicist said, “The ‘bottom’ came up so fast I thought we would hit a nunatak.”
Use of Major- and Minor-Element Mapping to Measure Chemical Variability in Diogenite Pyroxenes
NASA Astrophysics Data System (ADS)
Spilde, M. N.; Papike, J. J.
1993-07-01
Diogenite orthopyroxene grains have been shown to exhibit chemical variability within individual meteorite samples, e.g., the population groups reported by Hewins [1]. Our previous work [2] has shown a great deal of inter- and intragrain variability in OPX. The Garland diogenite, for example, appears to have two distinct populations of OPX, based on Cr/Al ratios. However, within individual crystals, excursions of Cr/Al ratios are present that may span a wide range within each population group. We are presently conducting SIMS analysis of OPX in diogenites and, therefore, the chemical variability of analyzed pyroxenes must be completely determined in order to find that portion of the crystal that most accurately records the igneous, rather than the metamorphic history. Optical analysis alone is not sufficient to categorize the pyroxene crystals. For example, numerous grains in EET 83246 appear to be zoned, with changes in interference colors toward the rims. However, EDS mapping indicates that the rims are chemically similar to the cores; the interference colors are interpreted to be due to some sort of grain abrasion process that occurred during brecciation. Backscattered image mapping at low magnification can identify intergrain variations and gross intragrain chemical variations, but this must be followed up with more detailed elemental mapping. Our microprobe employs a Link (Oxford) eXL II analyzer with full-stage automation, so that we can combine EDS maps of major elements with WDS maps of minor elements (Al, Ti, Mn, Cr). Large area maps (>1 mm) are produced using stage rastering to avoid defocusing of the WDS spectrometers. In a final step, quantitative elemental maps of target grains are produced, whereby the characteristic X-ray intensity collected at each map pixel is background suppressed and fitted against a standard intensity to yield an apparent concentration. Appropriate standards, close to the composition of the mapped grain, are used such that the apparent concentration is close to the real (ZAF-corrected) concentration. A number of grains have been mapped in Roda, Garland, EET 83246 and LEW 88008. Except for Garland, OPX grains are relatively homogeneous. Some large Roda grains show very fine (100) augite lamellae along with small augite blebs and scattered spinel along relict grain boundaries. Orthopyroxenes in Garland exhibit rare zoning and thin augite lamellae. Both symmetrical and asymmetrical zoning are evident in elemental maps; an example of nearly symmetrical zoning is shown in the Fe and Mg quantitative maps in Fig. 1, which appears in the hard copy (note a companion abstract [3] that illustrates a microprobe traverse across this grain). In addition, some grains show evidence of partial relict rims, indicating that the grains are brecciated fragments of larger, zoned grains. These brecciated pieces may explain some, but not all, of the intragrain variability seen in Garland. Because Cr decreases toward the rim while Al remains relatively constant, those fragments from the grain core will have higher Cr/Al ratios than fragments from the rim. Acknowledgment: This research was supported by NASA Grant NAGW-3347 and the Institute of Meteoritics. References: [1] Hewins R. (1980) LPSC XI, 441-443. [2] Papike J. J. et al. (1993) LPSC XXIV, 1109-110. [3] Papike J. J. and Spilde M. N. (1993), this volume.
Map Projections and the Visual Detective: How to Tell if a Map Is Equal-Area, Conformal, or Neither
ERIC Educational Resources Information Center
Olson, Judy M.
2006-01-01
The ability to see whether a map is equal-area, conformal, or neither is useful for looking intelligently at large-area maps. For example, only if a map is equal-area can reliable judgments of relative size be made. If a map is equal-area, latitude-longitude cells are equal in size between a given pair of parallels, the cells between a given pair…
Miller, Richard C.; Randers-Pehrson, Gerhard; Geard, Charles R.; Hall, Eric J.; Brenner, David J.
1999-01-01
Domestic, low-level exposure to radon gas is considered a major environmental lung-cancer hazard involving DNA damage to bronchial cells by α particles from radon progeny. At domestic exposure levels, the relevant bronchial cells are very rarely traversed by more than one α particle, whereas at higher radon levels—at which epidemiological studies in uranium miners allow lung-cancer risks to be quantified with reasonable precision—these bronchial cells are frequently exposed to multiple α-particle traversals. Measuring the oncogenic transforming effects of exactly one α particle without the confounding effects of multiple traversals has hitherto been unfeasible, resulting in uncertainty in extrapolations of risk from high to domestic radon levels. A technique to assess the effects of single α particles uses a charged-particle microbeam, which irradiates individual cells or cell nuclei with predefined exact numbers of particles. Although previously too slow to assess the relevant small oncogenic risks, recent improvements in throughput now permit microbeam irradiation of large cell numbers, allowing the first oncogenic risk measurements for the traversal of exactly one α particle through a cell nucleus. Given positive controls to ensure that the dosimetry and biological controls were comparable, the measured oncogenicity from exactly one α particle was significantly lower than for a Poisson-distributed mean of one α particle, implying that cells traversed by multiple α particles contribute most of the risk. If this result applies generally, extrapolation from high-level radon risks (involving cellular traversal by multiple α particles) may overestimate low-level (involving only single α particles) radon risks. PMID:9874764
Anatomy-driven multiple trajectory planning (ADMTP) of intracranial electrodes for epilepsy surgery.
Sparks, Rachel; Vakharia, Vejay; Rodionov, Roman; Vos, Sjoerd B; Diehl, Beate; Wehner, Tim; Miserocchi, Anna; McEvoy, Andrew W; Duncan, John S; Ourselin, Sebastien
2017-08-01
Epilepsy is potentially curable with resective surgery if the epileptogenic zone (EZ) can be identified. If non-invasive imaging is unable to elucidate the EZ, intracranial electrodes may be implanted to identify the EZ as well as map cortical function. In current clinical practice, each electrode trajectory is determined by time-consuming manual inspection of preoperative imaging to find a path that avoids blood vessels while traversing appropriate deep and superficial regions of interest (ROIs). We present anatomy-driven multiple trajectory planning (ADMTP) to find safe trajectories from a list of user-defined ROIs within minutes rather than the hours required for manual planning. Electrode trajectories are automatically computed in three steps: (1) Target Point Selection to identify appropriate target points within each ROI; (2) Trajectory Risk Scoring to quantify the cumulative distance to critical structures (blood vessels) along each trajectory, defined as the skull entry point to target point. (3) Implantation Plan Computation: to determine a feasible combination of low-risk trajectories for all electrodes. ADMTP was evaluated on 20 patients (190 electrodes). ADMTP lowered the quantitative risk score in 83% of electrodes. Qualitative results show ADMTP found suitable trajectories for 70% of electrodes; a similar portion of manual trajectories were considered suitable. Trajectory suitability for ADMTP was 95% if traversing sulci was not included in the safety criteria. ADMTP is computationally efficient, computing between 7 and 12 trajectories in 54.5 (17.3-191.9) s. ADMTP efficiently compute safe and surgically feasible electrode trajectories.
Risk analysis procedure for post-wildfire natural hazards in British Columbia
NASA Astrophysics Data System (ADS)
Jordan, Peter
2010-05-01
Following a severe wildfire season in 2003, and several subsequent damaging debris flow and flood events, the British Columbia Forest Service developed a procedure for analysing risks to public safety and infrastructure from such events. At the same time, the Forest Service undertook a research program to determine the extent of post-wildfire hazards, and examine the hydrologic and geomorphic processes contributing to the hazards. The risk analysis procedure follows the Canadian Standards Association decision-making framework for risk management (which in turn is based on international standards). This has several steps: identification of risk, risk analysis and estimation, evaluation of risk tolerability, developing control or mitigation strategies, and acting on these strategies. The Forest Service procedure deals only with the first two steps. The results are passed on to authorities such as the Provincial Emergency Program and local government, who are responsible for evaluating risks, warning residents, and applying mitigation strategies if appropriate. The objective of the procedure is to identify and analyse risks to public safety and infrastructure. The procedure is loosely based on the BAER (burned area emergency response) program in the USA, with some important differences. Our procedure focuses on identifying risks and warning affected parties, not on mitigation activities such as broadcast erosion control measures. Partly this is due to limited staff and financial resources. Also, our procedure is not multi-agency, but is limited to wildfires on provincial forest land; in British Columbia about 95% of forest land is in the publicly-owned provincial forest. Each fire season, wildfires are screened by size and proximity to values at risk such as populated areas. For selected fires, when the fire is largely contained, the procedure begins with an aerial reconnaissance of the fire, and photography with a hand-held camera, which can be used to make a preliminary map of vegetation burn severity if desired. The next steps include mapping catchment boundaries, field traverses to collect data on soil burn severity and water repellency, identification of unstable hillslopes and channels, and inspection of values at risk from hazards such as debris flows or flooding. BARC (burned area reflectance classification) maps based on satellite imagery are prepared for some fires, although these are typically not available for several weeks. Our objective is to make a preliminary risk analysis report available about two weeks after the fire is contained. If high risks to public safety or infrastructure are identified, the risk analysis reports may make recommendations for mitigation measures to be considered; however, acting on these recommendations is the responsibility of local land managers, local government, or landowners. Mitigation measures for some fires have included engineering treatments to reduce the hydrologic impact of logging roads, protective structures such as dykes or berms, and straw mulching to reduce runoff and erosion on severely burned areas. The Terrace Mountain Fire, with burned 9000 hectares in the Okanagan Valley in 2009, is used as an example of the application of the procedure.
Application of backpack Lidar to geological cross-section measurement
NASA Astrophysics Data System (ADS)
Lin, Jingyu; Wang, Ran; Xiao, Zhouxuan; Li, Lu; Yao, Weihua; Han, Wei; Zhao, Baolin
2017-11-01
As the traditional geological cross section measurement, the artificial traverse method was recently substituted by using point coordinates data. However, it is still the crux of the matter that how to acquire the high-precision point coordinates data quickly and economically. Thereby, the backpack Lidar is presented on the premise of the principle of using point coordinates in this issue. Undoubtedly, Lidar technique, one of booming and international active remote sensing techniques, is a powerful tool in obtaining precise topographic information, high-precision 3-D coordinates and building a real 3-D model. With field practice and date processing indoors, it is essentially accomplished that geological sections maps could be generated simply, accurately and automatically in the support of relevant software such as ArcGIS and LiDAR360.
Fault and joint measurements in Austin Chalk, Superconducting Super Collider Site, Texas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nance, H.S.; Laubach, S.E.; Dutton, A.R.
1994-12-31
Structure maps of 9.4 mi of nearly continuous tunnel excavations and more than 10 mi of other exposures and excavations in Austin Chalk at the Superconducting Super Collider (SSC) site in Ellis County, Texas, record normal-fault and joint populations in the subsurface within the northern segment of the Balcones Fault Zone with unmatched resolution for such a long traverse. Small faults (<10 ft throw) occur in clusters or swarms that have as many as 24 faults. Fault swarms are as much as 2,000 ft wide, and spacing between swarms ranges from 800 to 2,000 ft, averaging about 1,000 ft. Predominantlymore » northeast-trending joints are in swarms spaced 500 to more than 21,000 ft apart.« less
Novel 3D imaging techniques for improved understanding of planetary surface geomorphology.
NASA Astrophysics Data System (ADS)
Muller, Jan-Peter
2015-04-01
Understanding the role of different planetary surface formation processes within our Solar System is one of the fundamental goals of planetary science research. There has been a revolution in planetary surface observations over the past decade for Mars and the Moon, especially in 3D imaging of surface shape (down to resolutions of 75cm) and subsequent correction for terrain relief of imagery from orbiting and co-registration of lander and rover robotic images. We present some of the recent highlights including 3D modelling of surface shape from the ESA Mars Express HRSC (High Resolution Stereo Camera), see [1], [2] at 30-100m grid-spacing; and then co-registered to HRSC using a resolution cascade of 20m DTMs from NASA MRO stereo-CTX and 0.75m DTMs from MRO stereo-HiRISE [3]. This has opened our eyes to the formation mechanisms of megaflooding events, such as the formation of Iani Vallis and the upstream blocky terrain, to crater lakes and receding valley cuts [4]. A comparable set of products is now available for the Moon from LROC-WA at 100m [5] and LROC-NA at 1m [6]. Recently, a very novel technique for the super-resolution restoration (SRR) of stacks of images has been developed at UCL [7]. First examples shown will be of the entire MER-A Spirit rover traverse taking a stack of 25cm HiRISE to generate a corridor of SRR images along the rover traverse of 5cm imagery of unresolved features such as rocks, created as a consequence of meteoritic bombardment, ridge and valley features. This SRR technique will allow us for ˜400 areas on Mars (where 5 or more HiRISE images have been captured) and similar numbers on the Moon to resolve sub-pixel features. Examples will be shown of how these SRR images can be employed to assist with the better understanding of surface geomorphology. Acknowledgements: The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under PRoViDE grant agreement n° 312377. Partial support is also provided from the STFC 'MSSL Consolidated Grant' ST/K000977/1. References: [1] Gwinner, K., F. et al. (2010) Topography of Mars from global mapping by HRSC high-resolution digital terrain models and orthoimages: characteristics and performance. Earth and Planetary Science Letters 294, 506-519, doi:10.1016/j.epsl.2009.11.007, 2010; [2] Gwinner, K., F. et al. (2015) MarsExpress High Resolution Stereo Camera (HRSC) Multi-orbit Data Products: Methodology, Mapping Concepts and Performance for the first Quadrangle (MC-11E). Geophysical Research Abstracts, Vol. 17, EGU2015-13832; [3] Kim, J., & Muller, J. (2009). Multi-resolution topographic data extraction from Martian stereo imagery. Planetary and Space Science, 57, 2095-2112. doi:10.1016/j.pss.2009.09.024; [4] Warner, N. H., Gupta, S., Kim, J.-R., Muller, J.-P., Le Corre, L., Morley, J., et al. (2011). Constraints on the origin and evolution of Iani Chaos, Mars. Journal of Geophysical Research, 116(E6), E06003. doi:10.1029/2010JE003787; [5] Fok, H. S., Shum, C. K., Yi, Y., Araki, H., Ping, J., Williams, J. G., et al. (2011). Accuracy assessment of lunar topography models. Earth Planets Space, 63, 15-23. doi:10.5047/eps.2010.08.005; [6] Haase, I., Oberst, J., Scholten, F., Wählisch, M., Gläser, P., Karachevtseva, I., & Robinson, M. S. (2012). Mapping the Apollo 17 landing site area based on Lunar Reconnaissance Orbiter Camera images and Apollo surface photography - Haase - 2012 - Journal of Geophysical Research: Planets (1991-2012). Journal of Geophysical Research, 117, E00H20. doi:10.1029/2011JE003908; [7] Tao, Y., Muller, J.-P. (2015) Supporting lander and rover operation: a novel super-resolution restoration technique. Geophysical Research Abstracts, Vol. 17, EGU2015-6925
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dill, R.F.; Slosson, J.E.
1993-04-01
The configuration and stability of the present coast line near Abalone Cove, on the south side of Palos Verdes Peninsula, California is related to the geology, oceanographic conditions, and recent and ancient landslide activity. This case study utilizes offshore high resolution seismic profiles, side-scan sonar, diving, and coring, to relate marine geology to the stability of a coastal region with known active landslides utilizing a desk top computer and off-the-shelf software. Electronic navigation provided precise positioning that when applied to computer generated charts permitted correlation of survey data needed to define the offshore geology and sea floor sediment patterns. Amore » mackintosh desk-top computer and commercially available off-the-shelf software provided the analytical tools for constructing a base chart and a means to superimpose template overlays of topography, isopachs or sediment thickness, bottom roughness and sediment distribution patterns. This composite map of offshore geology and oceanography was then related to an extensive engineering and geological land study of the coastal zone forming Abalone Cove, an area of active landslides. Vibrocoring provided ground sediment data for high resolution seismic traverses. This paper details the systems used, present findings relative to potential landslide movements, coastal erosion and discuss how conclusions were reached to determine whether or not onshore landslide failures extend offshore.« less
NASA Astrophysics Data System (ADS)
Akinrinade, Opeyemi J.; Adesina, Rasheed B.
2016-06-01
This study provides a model for the prediction of groundwater potential and vulnerability of basement aquifers in parts of Akure, Southwestern Nigeria. Hydrogeophysical surveys involving very-low-frequency electromagnetic (VLF-EM) profiling and electrical resistivity (ER) sounding, as well as evaluation of hydraulic gradient using three-point method, were carried out. Ten VLF-EM reconnaissance survey traverses, with lengths ranging from 55 m to 75 m, at 10 m station separation, and 12 vertical electrical sounding (VES) stations were occupied. Two-dimensional map of the filtered real component reveals areas of high conductivity, indicative of linear features that can serve as a reservoir or conduit for fluid flow. Interpretation of the VES results delineates three to four geoelectric units. Two aquifer zones were identified, with resistivity values in the ranges of 20 Ωm to 310 Ωm and 100 Ωm to 3,000 Ω m, respectively. Transverse resistance, longitudinal conductance, coefficient of anisotropy and hydraulic gradient have values ranging from 318.2 Ωm2 to 1,041.8 Ωm2, 0.11 mhos to 0.39 mhos, 1.04 to 1.74 and 0.017 to 0.05, respectively. The results of this study identified two prospective borehole locations and the optimum position to site the proposed septic system, based on the aquifer's protective capacity and groundwater flow properties.
NASA Technical Reports Server (NTRS)
Olsen, Mark A.; Stanford, John L.
2001-01-01
We evaluate evidence for stratospheric mass transport into, and mass remaining in, the troposphere during an intense midlatitude cyclone. Mesoscale forecast model analysis fields from the Mesoscale Analysis and Prediction System were matched with total ozone observations from the Total Ozone Measurement Spectrometer. Combined with parcel back trajectory calculations, the analyses imply that two mechanisms contributed to the mass exchange: (1) An area of dynamically induced exchange was observed on the cyclone's southern edge. Parcels originally in the stratosphere crossed the jet core and were diluted through turbulent mixing with tropospheric air; (2) Diabetic effects reduced parcel potential vorticity (PC) for trajectories traversing precipitation regions, creating a 'PV hole' signature in the center of the cyclone. Air with characteristics of ozone and water vapor found in the lower stratosphere remained in the troposphere. The strength of the latter process may be unusual. Combined with other research, these results suggest that precipitation-induced diabetic effects can significantly modify (either decreasing or increasing) parcel potential vorticity, depending on parcel trajectory configuration with respect to maximum heating regions and jet core. The diabetic heating effect on stratosphere-troposphere exchange (STE) is more important to tropopause erosion than to altering parcel trajectories. In addition, these results underline the importance of using not only PC but also chemical constituents for diagnoses of STE.
Message passing with parallel queue traversal
Underwood, Keith D [Albuquerque, NM; Brightwell, Ronald B [Albuquerque, NM; Hemmert, K Scott [Albuquerque, NM
2012-05-01
In message passing implementations, associative matching structures are used to permit list entries to be searched in parallel fashion, thereby avoiding the delay of linear list traversal. List management capabilities are provided to support list entry turnover semantics and priority ordering semantics.
NASA Astrophysics Data System (ADS)
Yang, Yong; Li, Chengshan
2017-10-01
The effect of minor loop size on the magnetic stiffness has not been paid attention to by most researchers in experimental and theoretical studies about the high temperature superconductor (HTS) magnetic levitation system. In this work, we numerically investigate the average magnetic stiffness obtained by the minor loop traverses Δz (or Δx) varying from 0.1 mm to 2 mm in zero field cooling and field cooling regimes, respectively. The approximate values of the magnetic stiffness with zero traverse are obtained using the method of linear extrapolation. Compared with the average magnetic stiffness gained by any minor loop traverse, these approximate values are Not always close to the average magnetic stiffness produced by the smallest size of minor loops. The relative deviation ranges of average magnetic stiffness gained by the usually minor loop traverse (1 or 2 mm) are presented by the ratios of approximate values to average stiffness for different moving processes and two typical cooling conditions. The results show that most of average magnetic stiffness are remarkably influenced by the sizes of minor loop, which indicates that the magnetic stiffness obtained by a single minor loop traverse Δ z or Δ x, for example, 1 or 2 mm, can be generally caused a large deviation.
Wear-Induced Changes in FSW Tool Pin Profile: Effect of Process Parameters
NASA Astrophysics Data System (ADS)
Sahlot, Pankaj; Jha, Kaushal; Dey, G. K.; Arora, Amit
2018-06-01
Friction stir welding (FSW) of high melting point metallic (HMPM) materials has limited application due to tool wear and relatively short tool life. Tool wear changes the profile of the tool pin and adversely affects weld properties. A quantitative understanding of tool wear and tool pin profile is crucial to develop the process for joining of HMPM materials. Here we present a quantitative wear study of H13 steel tool pin profile for FSW of CuCrZr alloy. The tool pin profile is analyzed at multiple traverse distances for welding with various tool rotational and traverse speeds. The results indicate that measured wear depth is small near the pin root and significantly increases towards the tip. Near the pin tip, wear depth increases with increase in tool rotational speed. However, change in wear depth near the pin root is minimal. Wear depth also increases with decrease in tool traverse speeds. Tool pin wear from the bottom results in pin length reduction, which is greater for higher tool rotational speeds, and longer traverse distances. The pin profile changes due to wear and result in root defect for long traverse distance. This quantitative understanding of tool wear would be helpful to estimate tool wear, optimize process parameters, and tool pin shape during FSW of HMPM materials.
Red River of the North Reconnaissance Report: Sand Hill River Subbasin.
1980-12-01
Reservation. As the river traverses the beach ridge area, the width of the floodplain narrows markedly to a distance of no more than a quarter mile...studies are needed to determine its relative abundance and distribution. The Canadian toad and great plains toad , both recorded from the subbasin, are of...Beltrami and straightening and enlargement of the Sand Hill River and Sand Hill Ditch channel starting about 13 miles above the mouth to a point about six
DOE Office of Scientific and Technical Information (OSTI.GOV)
KLARER,PAUL R.; BINDER,ALAN B.; LENARD,ROGER X.
A preliminary set of requirements for a robotic rover mission to the lunar polar region are described and assessed. Tasks to be performed by the rover include core drill sample acquisition, mineral and volatile soil content assay, and significant wide area traversals. Assessment of the postulated requirements is performed using first order estimates of energy, power, and communications throughput issues. Two potential rover system configurations are considered, a smaller rover envisioned as part of a group of multiple rovers, and a larger single rover envisioned along more traditional planetary surface rover concept lines.
Non-linear Internal Wave Evolution in the South China Sea: 2005 Field Program
2009-05-01
Revelle in SCS05 (right). Soliton sightings from late April ( dark blue), early May (light blue) and mid May (yellow orange) are shown geographically...focus areas was the South China Sea (SCS). At that time, large-scale solitary waves were known to shoal on the western shelves of the SCS. Solitons ...we were gambling that solitons would indeed be traversing the central SCS and that they would already be well formed before reaching our approved
Brunyé, Tad T; Mahoney, Caroline R; Taylor, Holly A
2015-04-01
When navigating, people tend to overestimate distances when routes contain more turns, termed the route-angularity effect. Three experiments examined the source and generality of this effect. The first two experiments examined whether route-angularity effects occur while viewing maps and might be related to sex differences or sense of direction. The third experiment tested whether the route-angularity effect would occur with stimuli devoid of spatial context, reducing influences of environmental experience and visual complexity. In the three experiments, participants (N=1,552; M=32.2 yr.; 992 men, 560 women) viewed paths plotted on maps (Exps. 1 and 2) or against a blank background (Exp. 3). The depicted paths were always the same overall length, but varied in the number of turns (from 1 to 7) connecting an origin and destination. Participants were asked to estimate the time to traverse each path (Exp. 1) or the length of each path (Exps. 2 and 3). The Santa Barbara Sense of Direction questionnaire was administered to assess whether overall spatial sense of direction would be negatively related to the magnitude of the route-angularity effect. Repeated-measures analyses of variance (ANOVAs) indicated that paths with more turns elicited estimates of greater distance and travel times, whether they were depicted on maps or blank backgrounds. Linear regressions also indicated that these effects were significantly larger in those with a relatively low sense of direction. The results support the route-angularity effect and extend it to paths plotted on map-based stimuli. Furthermore, because the route-angularity effect was shown with paths plotted against blank backgrounds, route-angularity effects are not specific to understanding environments and may arise at the level of visual perception.
Wolfgruber, Thomas K; Sharma, Anupma; Schneider, Kevin L; Albert, Patrice S; Koo, Dal-Hoe; Shi, Jinghua; Gao, Zhi; Han, Fangpu; Lee, Hyeran; Xu, Ronghui; Allison, Jamie; Birchler, James A; Jiang, Jiming; Dawe, R Kelly; Presting, Gernot G
2009-11-01
We describe a comprehensive and general approach for mapping centromeres and present a detailed characterization of two maize centromeres. Centromeres are difficult to map and analyze because they consist primarily of repetitive DNA sequences, which in maize are the tandem satellite repeat CentC and interspersed centromeric retrotransposons of maize (CRM). Centromeres are defined epigenetically by the centromeric histone H3 variant, CENH3. Using novel markers derived from centromere repeats, we have mapped all ten centromeres onto the physical and genetic maps of maize. We were able to completely traverse centromeres 2 and 5, confirm physical maps by fluorescence in situ hybridization (FISH), and delineate their functional regions by chromatin immunoprecipitation (ChIP) with anti-CENH3 antibody followed by pyrosequencing. These two centromeres differ substantially in size, apparent CENH3 density, and arrangement of centromeric repeats; and they are larger than the rice centromeres characterized to date. Furthermore, centromere 5 consists of two distinct CENH3 domains that are separated by several megabases. Succession of centromere repeat classes is evidenced by the fact that elements belonging to the recently active recombinant subgroups of CRM1 colonize the present day centromeres, while elements of the ancestral subgroups are also found in the flanking regions. Using abundant CRM and non-CRM retrotransposons that inserted in and near these two centromeres to create a historical record of centromere location, we show that maize centromeres are fluid genomic regions whose borders are heavily influenced by the interplay of retrotransposons and epigenetic marks. Furthermore, we propose that CRMs may be involved in removal of centromeric DNA (specifically CentC), invasion of centromeres by non-CRM retrotransposons, and local repositioning of the CENH3.
Albert, Patrice S.; Koo, Dal-Hoe; Shi, Jinghua; Gao, Zhi; Han, Fangpu; Lee, Hyeran; Xu, Ronghui; Allison, Jamie; Birchler, James A.; Jiang, Jiming; Dawe, R. Kelly; Presting, Gernot G.
2009-01-01
We describe a comprehensive and general approach for mapping centromeres and present a detailed characterization of two maize centromeres. Centromeres are difficult to map and analyze because they consist primarily of repetitive DNA sequences, which in maize are the tandem satellite repeat CentC and interspersed centromeric retrotransposons of maize (CRM). Centromeres are defined epigenetically by the centromeric histone H3 variant, CENH3. Using novel markers derived from centromere repeats, we have mapped all ten centromeres onto the physical and genetic maps of maize. We were able to completely traverse centromeres 2 and 5, confirm physical maps by fluorescence in situ hybridization (FISH), and delineate their functional regions by chromatin immunoprecipitation (ChIP) with anti-CENH3 antibody followed by pyrosequencing. These two centromeres differ substantially in size, apparent CENH3 density, and arrangement of centromeric repeats; and they are larger than the rice centromeres characterized to date. Furthermore, centromere 5 consists of two distinct CENH3 domains that are separated by several megabases. Succession of centromere repeat classes is evidenced by the fact that elements belonging to the recently active recombinant subgroups of CRM1 colonize the present day centromeres, while elements of the ancestral subgroups are also found in the flanking regions. Using abundant CRM and non-CRM retrotransposons that inserted in and near these two centromeres to create a historical record of centromere location, we show that maize centromeres are fluid genomic regions whose borders are heavily influenced by the interplay of retrotransposons and epigenetic marks. Furthermore, we propose that CRMs may be involved in removal of centromeric DNA (specifically CentC), invasion of centromeres by non-CRM retrotransposons, and local repositioning of the CENH3. PMID:19956743
40 CFR Appendix A-1 to Part 60 - Test Methods 1 through 2F
Code of Federal Regulations, 2012 CFR
2012-07-01
... points are combined to form a single adjusted traverse point, treat the adjusted point as two separate... checks during the traverse (at least once per hour). Record all necessary data on a form similar to that...
40 CFR Appendix A-1 to Part 60 - Test Methods 1 through 2F
Code of Federal Regulations, 2010 CFR
2010-07-01
... points are combined to form a single adjusted traverse point, treat the adjusted point as two separate... checks during the traverse (at least once per hour). Record all necessary data on a form similar to that...
40 CFR Appendix A-1 to Part 60 - Test Methods 1 through 2F
Code of Federal Regulations, 2013 CFR
2013-07-01
... points are combined to form a single adjusted traverse point, treat the adjusted point as two separate... checks during the traverse (at least once per hour). Record all necessary data on a form similar to that...
40 CFR Appendix A-1 to Part 60 - Test Methods 1 through 2F
Code of Federal Regulations, 2011 CFR
2011-07-01
... points are combined to form a single adjusted traverse point, treat the adjusted point as two separate... checks during the traverse (at least once per hour). Record all necessary data on a form similar to that...
NASA Astrophysics Data System (ADS)
Connor, C. L.; Carstensen, R.; Domke, L.; Donohoe, S.; Clark, A.; Cordero, D.; Otsea, C.; Hakala, M.; Parks, R.; Lanwermeyer, S.; Discover Design Research (Ddr)
2010-12-01
Alaskan 10th and 11th graders earned college credit at Cape Decision Lighthouse as part of a 12-day, summer field research experience. Students and faculty flew to the southern tip of Kuiu Island located 388 km south of Juneau. Kuiu is the largest uninhabited island in southeastern Alaska. This field-based, introduction-to-research course was designed to engage students in the sciences and give them skills in technology, engineering, and mathematics. Two faculty, a forest naturalist and a geologist, introduced the students to the use of hand held GPS receivers, GIS map making, field note-taking and documentary photography, increment borer use, and soil studies techniques. Daily surveys across the region, provided onsite opportunities for the faculty to introduce the high schoolers to the many dimensions of forest ecology and plant succession. Students collected tree cores using increment borers to determine “release dates” providing clues to past wind disturbance. They discovered the influence of landscape change on the forest by digging soil pits and through guided interpretation of bedrock outcrops. The students learned about glacially influenced hydrology in forested wetlands during peat bog hikes. They developed an eye for geomorphic features along coastal traverses, which helped them to understand the influences of uplift through faulting and isostatic rebound in this tectonically active and once glaciated area. They surveyed forest patches to distinguish between regions of declining yellow-cedar from wind-disturbed spruce forests. The students encountered large volumes of primarily plastic marine debris, now stratified by density and wave energy, throughout the southern Kuiu intertidal zone. They traced pre-European Alaska Native subsistence use of the area, 19th and 20th century Alaska Territorial Maritime history, and learned about the 21st century radio tracking of over 10,000 commercial vessels by the Marine Exchange of Alaska from its many stations that include the Cape Decision Lighthouse. The students produced preliminary maps in ArcGIS and journals in Indesign, using laptops in a field camp GIS lab, powered by solar cells, at the Cape Decision Lighthouse. They presented the results of their research at a university convened Discover Design Research Forum in Juneau, at the end of their field work. The course was co-sponsored by the University Alaska Southeast, the Juneau Economic Development Council, and the Cape Decision Lighthouse Society.
NASA Astrophysics Data System (ADS)
Heldmann, Jennifer L.; Colaprete, Anthony; Elphic, Richard C.; Bussey, Ben; McGovern, Andrew; Beyer, Ross; Lees, David; Deans, Matt
2016-10-01
Studies of lunar polar volatile deposits are of interest for scientific purposes to understand the nature and evolution of the volatiles, and also for exploration reasons as a possible in situ resource to enable long term human exploration and settlement of the Moon. Both theoretical and observational studies have suggested that significant quantities of volatiles exist in the polar regions, although the lateral and horizontal distribution remains unknown at the km scale and finer resolution. A lunar polar rover mission is required to further characterize the distribution, quantity, and character of lunar polar volatile deposits at these higher spatial resolutions. Here we present a case study for NASA's Resource Prospector (RP) mission concept for a lunar polar rover and utilize this mission architecture and associated constraints to evaluate whether a suitable landing site exists to support an RP flight mission. We evaluate the landing site criteria to characterize the Haworth Crater region in terms of expected hydrogen abundance, surface topography, and prevalence of shadowed regions, as well as solar illumination and direct to Earth communications as a function of time to develop a notional rover traverse plan that addresses both science and engineering requirements. We also present lessons-learned regarding lunar traverse path planning focusing on the critical nature of landing site selection, the influence of illumination patterns on traverse planning, the effects of performing shadowed rover operations, the influence of communications coverage on traverse plan development, and strategic planning to maximize rover lifetime and science at end of mission. Here we present a detailed traverse path scenario for a lunar polar volatiles rover mission and find that the particular site north of Haworth Crater studied here is suitable for further characterization of polar volatile deposits.
Yang, Linlin; Zhao, Jun; Yu, Xinling; Zhang, Ruilong; Han, Guangmei; Liu, Renyong; Liu, Zhengjie; Zhao, Tingting; Han, Ming-Yong; Zhang, Zhongping
2018-04-16
Hydrogen sulfide (H2S) is a key signaling molecule in the cytoprotection, vascular mediation and neurotransmission of living organisms. In-depth understanding of its production, trafficking, and transformation in cells is very important in the way H2S mediates cellular signal transductions and organism functions; it also motivates the development of H2S probes and imaging technologies. A fundamental challenge, however, is how to engineer probes with sensitivity and cellular penetrability that allow detection of spontaneous production of H2S in the entire cell space and live animals. Here, we report a rationally designed molecular switch capable of accessing all intracellular compartments, including the nucleus, lysosomes and mitochondria, for H2S detection. Our probe comprised three functional domains (H2S sensing, fluorescence, and biomembrane penetration), could enter almost all cell types readily, and exhibit a rapid and ultrasensitive response to H2S (≤120-fold fluorescence enhancement) for the dynamic mapping of spontaneously produced H2S as well as its distribution in the whole cell. In particular, the probe traversed blood/tissue/cell barriers to achieve mapping of endogenous H2S in metabolic organs of a live Danio rerio (zebrafish). These results open-up exciting opportunities to investigate H2S physiology and H2S-related diseases.
This study describes the biogeochemical cycling of seston in Grand Traverse Bay, Lake Michigan. Seston was characterized by carbon and nitrogen elemental and isotopic abundances. Fluorescence, temperature, light transmittance, and concentrations of dissolved inorganic nitrogen we...
The Fate of a Normal Human Cell Traversed by a Single Charged Particle
NASA Astrophysics Data System (ADS)
Fournier, C.; Zahnreich, S.; Kraft, D.; Friedrich, T.; Voss, K.-O.; Durante, M.; Ritter, S.
2012-09-01
The long-term ``fate'' of normal human cells after single hits of charged particles is one of the oldest unsolved issues in radiation protection and cellular radiobiology. Using a high-precision heavy-ion microbeam we could target normal human fibroblasts with exactly one or five carbon ions and measured the early cytogenetic damage and the late behaviour using single-cell cloning. Around 70% of the first cycle cells presented visible aberrations in mFISH after a single ion traversal, and about 5% of the cells were still able to form colonies. In one third of selected high-proliferative colonies we observed clonal (radiation-induced) aberrations. Terminal differentiation and markers of senescence (PCNA, p16) in the descendants of cells traversed by one carbon ion occurred earlier than in controls, but no evidence of radiation-induced chromosomal instability was found. We conclude that cells surviving single-ion traversal, often carrying clonal chromosome aberrations, undergo accelerated senescence but maintain chromosomal stability.
The Fate of a Normal Human Cell Traversed by a Single Charged Particle
Fournier, C.; Zahnreich, S.; Kraft, D.; Friedrich, T.; Voss, K.-O.; Durante, M.; Ritter, S.
2012-01-01
The long-term “fate” of normal human cells after single hits of charged particles is one of the oldest unsolved issues in radiation protection and cellular radiobiology. Using a high-precision heavy-ion microbeam we could target normal human fibroblasts with exactly one or five carbon ions and measured the early cytogenetic damage and the late behaviour using single-cell cloning. Around 70% of the first cycle cells presented visible aberrations in mFISH after a single ion traversal, and about 5% of the cells were still able to form colonies. In one third of selected high-proliferative colonies we observed clonal (radiation-induced) aberrations. Terminal differentiation and markers of senescence (PCNA, p16) in the descendants of cells traversed by one carbon ion occurred earlier than in controls, but no evidence of radiation-induced chromosomal instability was found. We conclude that cells surviving single-ion traversal, often carrying clonal chromosome aberrations, undergo accelerated senescence but maintain chromosomal stability. PMID:22966418
Conformally symmetric traversable wormholes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boehmer, Christian G.; Harko, Tiberiu; Lobo, Francisco S. N.
2007-10-15
Exact solutions of traversable wormholes are found under the assumption of spherical symmetry and the existence of a nonstatic conformal symmetry, which presents a more systematic approach in searching for exact wormhole solutions. In this work, a wide variety of solutions are deduced by considering choices for the form function, a specific linear equation of state relating the energy density and the pressure anisotropy, and various phantom wormhole geometries are explored. A large class of solutions impose that the spatial distribution of the exotic matter is restricted to the throat neighborhood, with a cutoff of the stress-energy tensor at amore » finite junction interface, although asymptotically flat exact solutions are also found. Using the 'volume integral quantifier', it is found that the conformally symmetric phantom wormhole geometries may, in principle, be constructed by infinitesimally small amounts of averaged null energy condition violating matter. Considering the tidal acceleration traversability conditions for the phantom wormhole geometry, specific wormhole dimensions and the traversal velocity are also deduced.« less
Driving ATHLETE: Analysis of Operational Efficiency
NASA Technical Reports Server (NTRS)
Townsend, Julie; Mittman, David
2012-01-01
The All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) is a modular mobility and manipulation platform being developed to support NASA operations in a variety of missions, including exploration of planetary surfaces. The agile system consists of a symmetrical arrangement of six limbs, each with seven articulated degrees of freedom and a powered wheel. This design enables transport of bulky payloads over a wide range of terrain and is envisioned as a tool to mobilize habitats, power-generation equipment, and other supplies for long-range exploration and outpost construction. In FY2010, ATHLETE traversed more than 80 km in field environments over eight weeks of testing, demonstrating that the concept is well suited to long-range travel. Although ATHLETE is designed to travel at speeds of up to 5 kilometers per hour, the observed average traverse rate during field-testing rarely exceeded 1.5 kilometers per hour. This paper investigates sources of inefficiency in ATHLETE traverse operations and identifies targets for improvement of overall traverse rate.
Driving ATHLETE: Analysis of Operational Efficiency
NASA Technical Reports Server (NTRS)
Townsend, Julie; Mittman, David
2012-01-01
The All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) is a modular mobility and manipulation platform being developed to support NASA operations in a variety of missions, including exploration of planetary surfaces. The agile system consists of a symmetrical arrangement of six limbs, each with seven articulated degrees of freedom and a powered wheel. This design enables transport of bulky payloads over a wide range of terrain and is envisioned as a tool to mobilize habitats, power-generation equipment, and other supplies for long-range exploration and outpost construction. In 2010, ATHLETE traversed more than 80 km in field environments over eight weeks of testing, demonstrating that the concept is well suited to long-range travel. However, while ATHLETE is designed to travel at speeds of up to 5 kilometers per hour, the observed average traverse rate during field-testing rarely exceeded 1.5 kilometers per hour. This paper investigates sources of inefficiency in ATHLETE traverse operations and identifies targets for improvement of overall traverse rate.
Gerlach, T.M.; Delgado, H.; McGee, K.A.; Doukas, M.P.; Venegas, J.J.; Cardenas, L.
1997-01-01
Volcanic CO2 emission rate data are sparse despite their potential importance for constraining the role of magma degassing in the biogeochemical cycle of carbon and for assessing volcanic hazards. We used a LI-COR CO2 analyzer to determine volcanic CO2 emission rates by airborne measurements in volcanic plumes at Popocatépetl volcano on June 7 and 10, 1995. LI-COR sample paths of ∼72 m, compared with ∼1 km for the analyzer customarily used, together with fast Fourier transforms to remove instrument noise from raw data greatly improve resolution of volcanic CO2 anomalies. Parametric models fit to background CO2 provide a statistical tool for distinguishing volcanic from ambient CO2. Global Positioning System referenced flight traverses provide vastly improved data on the shape, coherence, and spatial distribution of volcanic CO2 in plume cross sections and contrast markedly with previous results based on traverse stacking. The continuous escape of CO2 and SO2 from Popocatépetl was fundamentally noneruptive and represented quiescent magma degassing from the top of a magma chamber ∼5 km deep. The average CO2 emission rate for January-June 1995 is estimated to be at least 6400 t d−1, one of the highest determined for a quiescently degassing volcano, although correction for downwind dispersion effects on volcanic CO2 indicates a higher rate of ∼9000 t d−1. Analysis of random errors indicates emission rates have 95% confidence intervals of ∼±20%, with uncertainty contributed mostly by wind speed variance, although the variance of plume cross-sectional areas during traversing is poorly constrained and possibly significant.
Role of laser beam radiance in different ceramic processing: A two wavelengths comparison
NASA Astrophysics Data System (ADS)
Shukla, Pratik; Lawrence, Jonathan
2013-12-01
Effects of laser beam radiance (brightness) of the fibre and the Nd3+:YAG laser were investigated during surface engineering of the ZrO2 and Si3N4 advanced ceramics with respect to dimensional size and microstructure of both of the advanced ceramics. Using identical process parameters, the effects of radiance of both the Nd3+:YAG laser and a fibre laser were compared thereon the two selected advanced ceramics. Both the lasers showed differences in each of the ceramics employed in relation to the microstructure and grain size as well as the dimensional size of the laser engineered tracks-notwithstanding the use of identical process parameters namely spot size; laser power; traverse speed; Gaussian beam modes; gas flow rate and gas composition as well the wavelengths. From this it was evident that the difference in the laser beam radiance between the two lasers would have had much to do with this effect. The high radiance fibre laser produced larger power per unit area in steradian when compared to the lower radiance of the Nd3+:YAG laser. This characteristically produced larger surface tracks through higher interaction temperature at the laser-ceramic interface. This in turn generated bigger melt-zones and different cooling rates which then led to the change in the microstructure of both the Si3N4 and ZrO2 advance ceramics. Owing to this, it was indicative that lasers with high radiance would result in much cheaper and cost effective laser assisted surface engineering processes, since lower laser power, faster traverse speeds, larger spot sizes could be used in comparison to lasers with lower radiance which require much slower traverse speed, higher power levels and finer spot sizes to induce the same effect thereon materials such as the advanced ceramics.
Geologic map of Chickasaw National Recreation Area, Murray County, Oklahoma
Blome, Charles D.; Lidke, David J.; Wahl, Ronald R.; Golab, James A.
2013-01-01
This 1:24,000-scale geologic map is a compilation of previous geologic maps and new geologic mapping of areas in and around Chickasaw National Recreation Area. The geologic map includes revisions of numerous unit contacts and faults and a number of previously “undifferentiated” rock units were subdivided in some areas. Numerous circular-shaped hills in and around Chickasaw National Recreation Area are probably the result of karst-related collapse and may represent the erosional remnants of large, exhumed sinkholes. Geospatial registration of existing, smaller scale (1:72,000- and 1:100,000-scale) geologic maps of the area and construction of an accurate Geographic Information System (GIS) database preceded 2 years of fieldwork wherein previously mapped geology (unit contacts and faults) was verified and new geologic mapping was carried out. The geologic map of Chickasaw National Recreation Area and this pamphlet include information pertaining to how the geologic units and structural features in the map area relate to the formation of the northern Arbuckle Mountains and its Arbuckle-Simpson aquifer. The development of an accurate geospatial GIS database and the use of a handheld computer in the field greatly increased both the accuracy and efficiency in producing the 1:24,000-scale geologic map.
Atmospheric Phase Delay in Sentinel SAR Interferometry
NASA Astrophysics Data System (ADS)
Krishnakumar, V.; Monserrat, O.; Crosetto, M.; Crippa, B.
2018-04-01
The repeat-pass Synthetic Aperture Radio Detection and Ranging (RADAR) Interferometry (InSAR) has been a widely used geodetic technique for observing the Earth's surface, especially for mapping the Earth's topography and deformations. However, InSAR measurements are prone to atmospheric errors. RADAR waves traverse the Earth's atmosphere twice and experience a delay due to atmospheric refraction. The two major layers of the atmosphere (troposphere and ionosphere) are mainly responsible for this delay in the propagating RADAR wave. Previous studies have shown that water vapour and clouds present in the troposphere and the Total Electron Content (TEC) of the ionosphere are responsible for the additional path delay in the RADAR wave. The tropospheric refractivity is mainly dependent on pressure, temperature and partial pressure of water vapour. The tropospheric refractivity leads to an increase in the observed range. These induced propagation delays affect the quality of phase measurement and introduce errors in the topography and deformation fields. The effect of this delay was studied on a differential interferogram (DInSAR). To calculate the amount of tropospheric delay occurred, the meteorological data collected from the Spanish Agencia Estatal de Meteorología (AEMET) and MODIS were used. The interferograms generated from Sentinel-1 carrying C-band Synthetic Aperture RADAR Single Look Complex (SLC) images acquired on the study area are used. The study area consists of different types of scatterers exhibiting different coherence. The existing Saastamoinen model was used to perform a quantitative evaluation of the phase changes caused by pressure, temperature and humidity of the troposphere during the study. Unless the phase values due to atmospheric disturbances are not corrected, it is difficult to obtain accurate measurements. Thus, the atmospheric error correction is essential for all practical applications of DInSAR to avoid inaccurate height and deformation measurements.
Overhead View of Area Surrounding Pathfinder
NASA Technical Reports Server (NTRS)
1997-01-01
Overhead view of the area surrounding the Pathfinder lander illustrating the Sojourner traverse. Red rectangles are rover positions at the end of sols 1-30. Locations of soil mechanics experiments, wheel abrasion experiments, and APXS measurements are shown. The A numbers refer to APXS measurements as discussed in the paper by Rieder et al. (p. 1770, Science Magazine, see image note). Coordinates are given in the LL frame.
The photorealistic, interactive, three-dimensional virtual reality (VR) terrain models were created from IMP images using a software package developed for Pathfinder by C. Stoker et al. as a participating science project. By matching features in the left and right camera, an automated machine vision algorithm produced dense range maps of the nearfield, which were projected into a three-dimensional model as a connected polygonal mesh. Distance and angle measurements can be made on features viewed in the model using a mouse-driven three-dimensional cursor and a point-and-click interface. The VR model also incorporates graphical representations of the lander and rover and the sequence and spatial locations at which rover data were taken. As the rover moved, graphical models of the rover were added for each position that could be uniquely determined using stereo images of the rover taken by the IMP. Images taken by the rover were projected into the model as two-dimensional 'billboards' to show the proper perspective of these images.NOTE: original caption as published in Science MagazineMars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).NASA Technical Reports Server (NTRS)
Robertson, Luke B.; Hintze, Paul; OConnor, Gregory W.
2009-01-01
We describe the conceptual method of an autonomously operable Direct Forming machine that would consume regolith or regolith slag to mold intimately, interlinked elements in a continuous process. The resulting product, one to three meter wide geomats, would be deployed over commonly traversed areas to isolate the astronauts and equipment from underlying dust. The porous geotextile would provide areas for dust settling, thereby mitigating dust impingement on astronaut suits or surface structures. Because of their self-supporting yet flexible structure, these geomats could be assembled into shields and buttresses to protect lunar habitants from radiation, forming a "flexoskeleton" from in situ materials.
Superficial Deposits at Gusev Crater Along Spirit Rover Traverses
NASA Technical Reports Server (NTRS)
Grant, J. A.; Arvidson, R.; Bell, J. F., III; Cabrol, N. A.; Carr, M. H.; Christensen, P.; Crumpler, L.; DesMarsais, D.; Ehlmann, B. L.; Ming, Douglas W.
2004-01-01
The Mars Exploration Rover Spirit has traversed a fairly flat, rock-strewn terrain whose surface is shaped primarily by impact events, although some of the landscape has been altered by eolian processes.Impacts ejected basaltic rocks that probably were part of locally formed lava flows from at least 10 meters depth.Some rocks have been textured and/or partially buried by windblown sediments less than 2 millimeters in diameter that concentrate within shallow, partially filled, circular impact depressions referred to as hollows.The terrain traversed during the 90-sol (martian solar day) nominal mission shows no evidence for an ancient lake in Gusev crater.
Surficial deposits at Gusev crater along Spirit Rover traverses
Grant, J. A.; Arvidson, R.; Bell, J.F.; Cabrol, N.A.; Carr, M.H.; Christensen, P.; Crumpler, L.; Des Marais, D.J.; Ehlmann, B.L.; Farmer, J.; Golombek, M.; Grant, F.D.; Greeley, R.; Herkenhoff, K.; Li, R.; McSween, H.Y.; Ming, D. W.; Moersch, J.; Rice, J. W.; Ruff, S.; Richter, L.; Squyres, S.; Sullivan, R.; Weitz, C.
2004-01-01
The Mars Exploration Rover Spirit has traversed a fairly flat, rock-strewn terrain whose surface is shaped primarily by impact events, although some of the landscape has been altered by eolian processes. Impacts ejected basaltic rocks that probably were part of locally formed lava flows from at least 10 meters depth. Some rocks have been textured and/or partially buried by windblown sediments less than 2 millimeters in diameter that concentrate within shallow, partially filled, circular impact depressions referred to as hollows. The terrain traversed during the 90-sol (martian solar day) nominal mission shows no evidence for an ancient lake in Gusev crater.
Magnetic tracing of material from a point source in a river system
NASA Astrophysics Data System (ADS)
Appel, Erwin; Liu, Zhao; Mülller, Christina; Frančišković-Bilinski, Stanislav; Rösler, Wolfgang; Zhang, Qi
2017-04-01
In fluvial environment, the mechanism of transport, distribution, and fate of contaminants, and the resulting distribution patterns are complex but only limited studied. A case in Croatia where highly magnetic coal slag was dumped into a river for more than one century (1884-1994) offers an ideal target for studying principles of how to capture the magnetic record of environmental pollution in a river system originating from a well-defined point source. Downstream transport of the coal slag can be roughly recognized by simple sampling of river sediments, but this approach is poorly significant due to the extremely variable magnetic properties caused by hydrodynamic sorting. We suggest applying variogram analyses in river traverses to obtain more reliable values of magnetic concentration, and combining these results with modeling of river bottom magnetic anomalies in order to estimate the amount of coal slag at certain positions. A major focus of this presentation is the translocation of coal slag material to the riverbanks by flooding, i.e. the possible identification of flood affected areas and the discrimination of different flood events. Surface magnetic susceptibility (MS) mapping clearly outlines the extent of flooded areas, and repeated measurements after one year reveal the reach of two recent smaller floods within this period by spatial delineation of strong positive and negative changes of MS values. To identify older flood signatures, dense grids of vertical MS profiles were analyzed at two riverbank areas in two different ways. First, by determining differences between depth horizons at the measurement points, and second, by contouring the vertical MS profiles as a function of the distance to the river (area with flat riverbank topography) and as a function of terrain elevation (area with oblique riverbank). Single flood events cannot be discriminated, but the second approach allows to approximately identify the extent of major historical floods which were interrupted by longer periods of less intensive flooding. The so far obtained results suggest that a more detailed magnetic study of this 'Croatian case' can contribute to better understanding of material displacement in a river system and how to perform significant sampling of river sediments.
Lunar Surface Potential Changes Possible Associated with Traversals of the Bow Shock
NASA Technical Reports Server (NTRS)
Collier, M. R.; Stubbs, T. J.; Hills, H. K.
2008-01-01
We report an analysis of seven Apollo 14 Apollo Lunar Surface Experiments Package (ALSEP) Suprathermal Ion Detector Experiment (SIDE) "resonance" events from January 1972 through January 1973. The events appear to be associated with traversals of the Moon through the terrestrial bow shock.
NASA Astrophysics Data System (ADS)
Tan, Adrian Wei-Yee; Sun, Wen; Phang, Yun Peng; Dai, Minghui; Marinescu, Iulian; Dong, Zhili; Liu, Erjia
2017-10-01
Cold spray has the potential to restore damaged aerospace components made from titanium alloy, Ti6Al4V at low temperature (200-400 °C). Traverse scanning speed during deposition is one of the key factors that affect the quality of the Ti6Al4V coatings as it influences the thermal build-up and coating thickness per pass. As there are fewer reported studies on this, this work investigated the effects of different traverse scanning speeds (100, 300 and 500 mm/s) of cold spray nozzle on the microstructure and mechanical properties of cold-sprayed Ti6Al4V coatings. The cross-sectional analysis showed coating porosities reduces with slower traverse speed, from 3.2 to 0.5%. In addition, the microhardness of the coatings increased from about 361-385 HV due to strain hardening. However, the adhesion strength of the coatings to the substrates significantly decreased with reduced traverse speed from about 60 MPa (glue failure) at 500 mm/s to 2.5 MPa (interface failure) at 100 mm/s. Therefore, this study revealed that the control of heat build-up and thickness per pass during the cold spray deposition of the Ti6Al4V coatings is crucial to attain the desirable properties of the coatings.
Lichtenberg, K.A.; Arvidson, R. E.; Poulet, F.; Morris, R.V.; Knudson, A.; Bell, J.F.; Bellucci, G.; Bibring, J.-P.; Farrand, W. H.; Johnson, J. R.; Ming, D. W.; Pinet, P.C.; Rogers, A.D.; Squyres, S. W.
2007-01-01
Comparison of the Mars Exploration Rover Spirit's Pancam (0.4 to 1.0 ??m) and Mars Express Observatoire pour la Mineralogie l'Eau, les Glaces et l'Activite?? (OMEGA) (0.4 to 2.5 ??m) spectral reflectance data over Spirit's traverses shows that Gusev cratered plains are dominated by nanophase ferric-oxide-rich dust covering weakly altered basaltic sands. This interpretation is also consistent with both observations from OMEGA data covering plains beyond the traverse region and interpretations of data from the other payload instruments on the Spirit Rover. OMEGA observations of relatively low albedo regions where dust has presumably been stripped by dust devils show negative spectral reflectance slopes from 1.5 to 2.5 ??m and moderately masked spectral features which are indicative of olivine or pyroxene. High-albedo regions north and south of the Spirit landing site have flat spectral reflectance slopes and few spectral features, although all spectra have a nanophase ferric-oxide absorption edge between 0.4 and 0.75 ??m. Comparison of THEMIS-derived thermal inertia values with OMEGA-derived spectral parameters shows that although the dust cover can be optically thick (0.4 to 2.5 ??m wavelength region) in some areas, it is not thick enough (???1 cm) to mask the thermal inertia of the underlying substrate for areas included in this study. Copyright 2007 by the American Geophysical Union.
Hu, Shishan; Fruin, Scott; Kozawa, Kathleen; Mara, Steve; Winer, Arthur M.
2013-01-01
We observed elevated air pollutant concentrations, especially of ultrafine particles (UFP), black carbon (BC) and NO, across the residential neighborhood of the Boyle Heights Community (BH) of Los Angeles, California. Using an electric vehicle mobile platform equipped with fast response instruments, real-time air pollutant concentrations were measured in BH in spring and summer of 2008. Pollutant concentrations varied significantly in the two seasons, on different days, and by time of day, with an overall average UFP concentration in the residential areas of ~33 000 cm−3. The averaged UFP, BC, and NO concentrations measured on Soto St, a major surface street in BH, were 57 000 cm−3, 5.1 µg m−3, and 67 ppb, respectively. Concentrations of UFP across the residential areas in BH were nearly uniform spatially, in contrast to other areas in the greater metropolitan area of Los Angeles where UFP concentrations exhibit strong gradients downwind of roadways. We attribute this “UFP cloud” to high traffic volumes, including heavy duty diesel trucks on the freeways which surround and traverse BH, and substantial numbers of high-emitting vehicles (HEVs) on the surface streets traversing BH. Additionally, the high density of stop signs and lights and short block lengths, requiring frequent accelerations of vehicles, may contribute. The data also support a role for photochemical production of UFP in the afternoon. UFP concentration peaks (5 s average) of up to 9 million particles cm−3 were also observed immediately behind HEVs when they accelerated from stop lights in the BH neighborhood and areas immediately adjacent. Although encounters with HEV during mornings accounted for only about 6% and 17% of time spent monitoring residential areas and major surface streets, HEV contributed to about 28% and 53% of total ultrafine particles measured on the route, respectively. The observation of elevated pollutant number concentrations across the Boyle Heights community highlights how multiple factors combine to create high pollutant levels, and has important human exposure assessment implications, including the potential utility of our data as inputs to epidemiological studies. PMID:23997642
NASA Astrophysics Data System (ADS)
Hu, Shishan; Paulson, Suzanne E.; Fruin, Scott; Kozawa, Kathleen; Mara, Steve; Winer, Arthur M.
2012-05-01
We observed elevated air pollutant concentrations, especially of ultrafine particles (UFP), black carbon (BC) and NO, across the residential neighborhood of the Boyle Heights Community (BH) of Los Angeles, California. Using an electric vehicle mobile platform equipped with fast response instruments, real-time air pollutant concentrations were measured in BH in spring and summer of 2008. Pollutant concentrations varied significantly in the two seasons, on different days, and by time of day, with an overall average UFP concentration in the residential areas of ∼33 000 cm-3. The averaged UFP, BC, and NO concentrations measured on Soto St, a major surface street in BH, were 57 000 cm-3, 5.1 μg m-3, and 67 ppb, respectively. Concentrations of UFP across the residential areas in BH were nearly uniform spatially, in contrast to other areas in the greater metropolitan area of Los Angeles where UFP concentrations exhibit strong gradients downwind of roadways. We attribute this “UFP cloud” to high traffic volumes, including heavy duty diesel trucks on the freeways which surround and traverse BH, and substantial numbers of high-emitting vehicles (HEVs) on the surface streets traversing BH. Additionally, the high density of stop signs and lights and short block lengths, requiring frequent accelerations of vehicles, may contribute. The data also support a role for photochemical production of UFP in the afternoon. UFP concentration peaks (5 s average) of up to 9 million particles cm-3 were also observed immediately behind HEVs when they accelerated from stop lights in the BH neighborhood and areas immediately adjacent. Although encounters with HEV during mornings accounted for only about 6% and 17% of time spent monitoring residential areas and major surface streets, HEV contributed to about 28% and 53% of total ultrafine particles measured on the route, respectively. The observation of elevated pollutant concentrations across the Boyle Heights community highlights how multiple factors combine to create high pollutant levels, and has important human exposure assessment implications, including the potential utility of our data as inputs to epidemiological studies.
NASA Technical Reports Server (NTRS)
Lo, C. P.; Quattrochi, Dale A.
2003-01-01
Land use and land cover maps of Atlanta Metropolitan Area in Georgia were produced from Landsat MSS and TM images for 1973,1979,1983,1987,1992, and 1997, spanning a period of 25 years. Dramatic changes in land use and land cover have occurred with loss of forest and cropland to urban use. In particular, low-density urban use, which includes largely residential use, has increased by over 119% between 1973 and 1997. These land use and land cover changes have drastically altered the land surface characteristics. An analysis of Landsat images revealed an increase in surface temperature and a decline in NDVI from 1973 to 1997. These changes have forced the development of a significant urban heat island effect and an increase in ground level ozone production to such an extent, that Atlanta has violated EPA's ozone level standard in recent years. The urban heat island initiated precipitation events that were identified between 1996 and 2000 tended to occur near high-density urban areas but outside the I-285 loop that traverses around the Central Business District, i.e. not in the inner city area, but some in close proximity to the highways. The health implications were investigated by comparing the spatial patterns of volatile organic compounds (VOC) and nitrogen oxides (NOx) emissions, the two ingredients that form ozone by reacting with sunlight, with those of rates of cardiovascular and chronic lower respiratory diseases. A clear core-periphery pattern was revealed for both VOC and NOx emissions, but the spatial pattern was more random in the cases of rates of cardiovascular and chronic lower respiratory diseases. Clearly, factors other than ozone pollution were involved in explaining the rates of these diseases. Further research is therefore needed to understand the health geography and its relationship to land use and land cover change as well as urban heat island effect. This paper illustrates the usefulness of a remote sensing approach for this purpose.
Carrara, Paul E.
2007-01-01
The Tok area 1:100,000-scale map, through which the Alaska Highway runs, is in east-central Alaska about 160 km west of the Yukon border. The surficial geologic mapping in the map area is in support of the 'Geologic Mapping in support of land, resources, and hazards issues in Alaska' Project of the USGS National Cooperative Geologic Mapping Program. The Tok map area contains parts of three physiographic provinces, the Alaska Range, the Yukon-Tanana Upland, and the Northway-Tanana Lowland. The high, rugged, glaciated landscape of the eastern Alaska Range dominates the southwestern map area. The highest peak, an unnamed summit at the head of Cathedral Rapids Creek No. 2, rises to 2166 m. The gently rolling hills of the Yukon-Tanana Upland, in the northern map area, rise to about 1000 m. The Northway-Tanana Lowland contains the valley of the westerly flowing Tanana River. Elevations along the floor of the lowland generally range between 470 and 520 m. The dominant feature within the map is the Tok fan, which occupies about 20 percent of the map area. This large (450 km2), nearly featureless fan contains a high percentage of volcanic clasts derived from outside the present-day drainage of the Tok River. Because the map area is dominated by various surficial deposits, the map depicts 26 different surficial units consisting of man-made, alluvial, colluvial, eolian, lacustrine, organic, glaciofluvial, glacial, and periglacial deposits. The accompanying table provides information concerning the various units including their properties, characteristics, resource potential, and associated hazards in this area of the upper Tanana valley.
Instantaneous phase mapping deflectometry for dynamic deformable mirror characterization
NASA Astrophysics Data System (ADS)
Trumper, Isaac; Choi, Heejoo
2017-09-01
We present an instantaneous phase mapping deflectometry (PMD) system in the context of measuring a continuous surface deformable mirror (DM). Deflectometry has a high dynamic range, enabling the full range of surfaces generated by the DM to be measured. The recent development of an instantaneous PMD system leverages the simple setup of the PMD system to measure dynamic objects with accuracy similar to an interferometer. To demonstrate the capabilities of this technology, we perform a linearity measurement of the actuator motion in a continuous surface DM, which is critical for closed loop control in adaptive optics applications. We measure the entire set of actuators across the DM as they traverse their full range of motion with a Shack-Hartman wavefront sensor, thereby obtaining the influence function. Given the influence function of each actuator, the DM can produce specific Zernike terms on its surface. We then measure the linearity of the Zernike modes available in the DM software using the instantaneous PMD system. By obtaining the relationship between modes, we can more accurately generate surface profiles composed of Zernike terms. This ability is useful for other dynamic freeform metrology applications that utilize the DM as a null component.
Toward mapping the biology of the genome.
Chanock, Stephen
2012-09-01
This issue of Genome Research presents new results, methods, and tools from The ENCODE Project (ENCyclopedia of DNA Elements), which collectively represents an important step in moving beyond a parts list of the genome and promises to shape the future of genomic research. This collection sheds light on basic biological questions and frames the current debate over the optimization of tools and methodological challenges necessary to compare and interpret large complex data sets focused on how the genome is organized and regulated. In a number of instances, the authors have highlighted the strengths and limitations of current computational and technical approaches, providing the community with useful standards, which should stimulate development of new tools. In many ways, these papers will ripple through the scientific community, as those in pursuit of understanding the "regulatory genome" will heavily traverse the maps and tools. Similarly, the work should have a substantive impact on how genetic variation contributes to specific diseases and traits by providing a compendium of functional elements for follow-up study. The success of these papers should not only be measured by the scope of the scientific insights and tools but also by their ability to attract new talent to mine existing and future data.
Trace element mapping in Parkinsonian brain by quantitative ion beam microscopy
NASA Astrophysics Data System (ADS)
Barapatre, Nirav; Morawski, Markus; Butz, Tilman; Reinert, Tilo
2010-06-01
The role of iron in the pathogenesis of the Parkinson's disease (PD) is a current subject of research in Neurochemistry, since an abnormal increase in iron is reported in the substantia nigra (SN) of Parkinsonian patients. A severe loss of the cells containing dopamine in the SN in the PD has also drawn attention towards the function of a browny-black pigment called neuromelanin, which accumulates predominantly in these dopaminergic neurons. The neuromelanin has an ability to chelate metal ions, which, in free state, may cause considerable damage to cells by reacting with their lipid-rich membranes. However, it could also potentiate free radical production if it releases the bound metal ions. The highly sensitive and non-destructive micro-PIXE method suits best to quantify and map the trace elements in the SN. The accuracy in charge measurement for such microanalysis studies is of utmost importance for quantitative analysis. Since a Faraday cup is usually placed behind the thin biological sample to measure the charge, the primary and the secondary electrons, knocked out from the sample by traversing ion beam, hamper an exact charge determination. Hence, a new non-interceptive technique was developed for precise charge measurement and for continuous monitoring of beam current.
Total Solar Eclipse of 2006 March 29
NASA Technical Reports Server (NTRS)
Espenak, F.; Anderson, J.
2004-01-01
On 2006 March 29, a total eclipse of the Sun will be visible from within a narrow corridor which traverses half the Earth. The path of the Moon's umbral shadow begins in Brazil and extends across the Atlantic, northern Africa, and central Asia where it ends at sunset in western Mongolia. A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes the northern two thirds of Africa, Europe, and central Asia.Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for approximately 350 cities, maps of the eclipse path, weather prospects, the lunar limb profile, and the sky during totality. Information on safe eclipse viewing and eclipse photography is included.
Near real-time stereo vision system
NASA Technical Reports Server (NTRS)
Anderson, Charles H. (Inventor); Matthies, Larry H. (Inventor)
1993-01-01
The apparatus for a near real-time stereo vision system for use with a robotic vehicle is described. The system is comprised of two cameras mounted on three-axis rotation platforms, image-processing boards, a CPU, and specialized stereo vision algorithms. Bandpass-filtered image pyramids are computed, stereo matching is performed by least-squares correlation, and confidence ranges are estimated by means of Bayes' theorem. In particular, Laplacian image pyramids are built and disparity maps are produced from the 60 x 64 level of the pyramids at rates of up to 2 seconds per image pair. The first autonomous cross-country robotic traverses (of up to 100 meters) have been achieved using the stereo vision system of the present invention with all computing done onboard the vehicle. The overall approach disclosed herein provides a unifying paradigm for practical domain-independent stereo ranging.
DspaceOgreTerrain 3D Terrain Visualization Tool
NASA Technical Reports Server (NTRS)
Myint, Steven; Jain, Abhinandan; Pomerantz, Marc I.
2012-01-01
DspaceOgreTerrain is an extension to the DspaceOgre 3D visualization tool that supports real-time visualization of various terrain types, including digital elevation maps, planets, and meshes. DspaceOgreTerrain supports creating 3D representations of terrains and placing them in a scene graph. The 3D representations allow for a continuous level of detail, GPU-based rendering, and overlaying graphics like wheel tracks and shadows. It supports reading data from the SimScape terrain- modeling library. DspaceOgreTerrain solves the problem of displaying the results of simulations that involve very large terrains. In the past, it has been used to visualize simulations of vehicle traverses on Lunar and Martian terrains. These terrains were made up of billions of vertices and would not have been renderable in real-time without using a continuous level of detail rendering technique.
Localization from Visual Landmarks on a Free-Flying Robot
NASA Technical Reports Server (NTRS)
Coltin, Brian; Fusco, Jesse; Moratto, Zack; Alexandrov, Oleg; Nakamura, Robert
2016-01-01
We present the localization approach for Astrobee,a new free-flying robot designed to navigate autonomously on board the International Space Station (ISS). Astrobee will conduct experiments in microgravity, as well as assisst astronauts and ground controllers. Astrobee replaces the SPHERES robots which currently operate on the ISS, which were limited to operating in a small cube since their localization system relied on triangulation from ultrasonic transmitters. Astrobee localizes with only monocular vision and an IMU, enabling it to traverse the entire US segment of the station. Features detected on a previously-built map, optical flow information,and IMU readings are all integrated into an extended Kalman filter (EKF) to estimate the robot pose. We introduce several modifications to the filter to make it more robust to noise.Finally, we extensively evaluate the behavior of the filter on atwo-dimensional testing surface.
NASA Technical Reports Server (NTRS)
Blacic, James D.
1992-01-01
A Teleoperated Lunar Explorer, or TOPLEX, consisting of a lunar lander payload in which a small, instrument-carrying lunar surface rover is robotically landed and teleoperated from Earth to perform extended lunar geoscience and resource evaluation traverses is proposed. The rover vehicle would mass about 100 kg and carry approximately 100 kg of analytic instruments. Four instruments are envisioned: (1) a Laser-Induced Breakdown Spectrometer (LIBS) for geochemical analysis at ranges up to 100 m, capable of operating in three different modes; (2) a combined x-ray fluorescence and x-ray diffraction (XRF/XRD) instrument for elemental and mineralogic analysis of acquired samples; (3) a mass spectrometer system for stepwise heating analysis of gases released from acquired samples; and (4) a geophysical instrument package for subsurface mapping of structures such as lava tubes.
Total Solar Eclipse of 2001 June 21
NASA Technical Reports Server (NTRS)
Espenak, Fred; Anderson, Jay
1999-01-01
On 2001 June 21, a total eclipse of the Sun will be visible from within a narrow corridor which traverses the Southern Hemisphere. The path of the Moon's umbral shadow begins in the South Atlantic, crosses southern Africa and Madagascar, and ends at sunset in the Indian Ocean. A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes eastern South America and the southern two thirds of Africa. Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for approximately 350 cities, maps of the eclipse path, weather prospects, the lunar limb profile and the sky during totality. Tips and suggestions are also given on how to safely view and photograph the eclipse.
Total Solar Eclipse of 2002 December 04
NASA Technical Reports Server (NTRS)
Espenak, Fred; Anderson, Jay
2001-01-01
On 2002 December 04, a total eclipse of the Sun will be visible from within a narrow corridor which traverses the Southern Hemisphere. The path of the Moon's umbral shadow begins in the South Atlantic, crosses southern Africa and the Indian Ocean, and ends at sunset in southern Australia. A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes the southern two thirds of Africa, Antarctica, Indian Ocean and Australia. Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for approximately 400 cities, maps of the eclipse path, weather prospects, the lunar limb profile and the sky during totality. Information on safe eclipse viewing and eclipse photography is included.
NASA Astrophysics Data System (ADS)
Muller, Jan-Peter
2015-04-01
Understanding the role of scaling in different planetary surface processes within our Solar System is one of the fundamental goals of planetary and solid earth scientific research. There has been a revolution in planetary surface observations over the past decade for the Earth, Mars and the Moon, especially in 3D imaging of surface shape (from the planetary scale down to resolutions of 75cm). I will examine three areas that I have been active in over the last 25 years giving examples of newly processed global datasets ripe for scaling analysis: topography, BRDF/albedo and imaging. For understanding scaling in terrestrial land surface topography we now have global 30m digital elevation models (DEMs) from different types of sensors (InSAR and stereo-optical) along with laser altimeter data to provide global reference models (to better than 1m in cross-over areas) and airborne laser altimeter data over small areas at resolutions better than 1m and height accuracies better than 10-15cm. We also have an increasing number of sub-surface observations from long wavelength SAR in arid regions, which will allow us to look at the true surface rather than the one buried by sand. We also still have a major limitation of these DEMs in that they represent an unknown observable surface with C-band InSAR DEMs representing being somewhere near the top of the canopy and X-band InSAR and stereo near the top of the canopy but only P-band representing the true understorey surface. I will present some of the recent highlights of topography on Mars including 3D modelling of surface shape from the ESA Mars Express HRSC (High Resolution Stereo Camera), see [1], [2] at 30-100m grid-spacing; and then co-registered to HRSC using a resolution cascade of 20m DTMs from NASA MRO stereo-CTX and 0.75m digital terrain models (as there is no land cover on Mars) DTMs from MRO stereo-HiRISE [3]. Comparable DTMs now exist for the Moon from 100m up to 1m. I will show examples of these DEM/DTM datasets along with some simple analyses of their scaling properties. Global 1km, 8-daily terrestrial land surface BRDF/albedo maps exist for US sensors from MODIS and by orbit from MISR. More recently, the ESA GlobAlbedo project [4] has produced land surface datasets on the same spatio-temporal sampling using optimal estimation with full uncertainty matrices associated with each and every 1km pixel. By exploiting these uncertainty estimates I show how upscaling can be performed as well as analysing their scaling properties. Recently, a very novel technique for the super-resolution restoration (SRR) of stacks of images has been developed at UCL [5]. First examples shown will be of the entire MER-A Spirit rover traverse taking a stack of 25cm HiRISE to generate a corridor of SRR images along the rover traverse of 5cm imagery of unresolved features such as rocks, created as a consequence of meteoritic bombardment, ridge and valley features. This SRR technique will allow us for ≈400 areas on Mars (where 5 or more HiRISE images have been captured) and similar numbers on the Moon to resolve sub-pixel features. Examples will be shown of how these SRR images can be employed to assist with the better understanding of surface geomorphology. Acknowledgements: The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under PRoViDE grant agreement n˚312377 and the ESA GlobAlbedo project. Partial support is also provided from the STFC "MSSL Consolidated Grant" ST/K000977/1. References: [1] Gwinner, K., F. et al. (2010) Topography of Mars from global mapping by HRSC high-resolution digital terrain models and orthoimages: characteristics and performance. Earth and Planetary Science Letters 294, 506-519, doi:10.1016/j.epsl.2009.11.007, 2010; [2] Gwinner, K., Muller, J-P., et al. (2015) MarsExpress High Resolution Stereo Camera (HRSC) Multi-orbit Data Products: Methodology, Mapping Concepts and Performance for the first Quadrangle (MC-11E). Geophysical Research Abstracts, Vol. 17, EGU2015-13832; [3] Kim, J., & Muller, J. (2009). Multi-resolution topographic data extraction from Martian stereo imagery. Planetary and Space Science, 57, 2095-2112. doi:10.1016/j.pss.2009.09.024; [4] Muller, J.-P., et al. (2011), The ESA GlobAlbedo Project for mapping the Earth's land surface albedo for 15 Years from European Sensors., Geophysical Research Abstracts, Vol. 13, EGU2011-10969; [5] Tao, Y., Muller, J.-P. (2015) Supporting lander and rover operation: a novel super-resolution restoration technique. Geophysical Research Abstracts, Vol. 17, EGU2015-6925
Using ESRI Story Maps for Engaging Tribal Youth in Localized Climate Education
NASA Astrophysics Data System (ADS)
Masters, E. L.; Marsik, F. J.; Sonderegger, C.
2017-12-01
A critical step in any climate adaptation initiative is the engagement of the community through educational outreach about the impacts of climate change on vulnerable economic, infrastructure and natural resources within the community. For Tribal communities, such outreach must also highlight connections between these vulnerable assets, such as natural resources, and Tribal cultural practices. For adult members of these communities, the combination of traditional ecological knowledge and western science approaches can prove effective in this regard. For Tribal youth, the often complex and data-heavy nature of western science approaches may prove to be more of an obstacle than an aid in communicating the impacts of our changing climate on their local Tribal community. A collaborative educational effort between the Grand Traverse Band of Ottawa and Chippewa Indians (Peshawbestown, MI) and the University of Michigan seeks to lean upon the rich tradition of storytelling as a method of conveying information to younger generations. The ESRI Story Maps platform provides such a tool through its combined use of narratives, images, maps, and data. The ability to make a Story Map deep and complex, or simple and fun, makes this application ideal for communicating with a range of people, from school-age children to adults. For our project, we created two Story Maps with different complexity levels, with one for elementary to middle school students, and the other targeted at high school students. The project for younger children was aimed at engaging viewers through a series of images and maps, introducing them to the basics of what wetlands are, which types of wetlands can be found locally, Indigenous cultural connections to wetlands, and how to protect wetlands. The more complex project provided a more expansive discussion of these same topics, including threats to these wetlands from human activities, including climate change, as well as an extensive list of references and a glossary of terms that allow the older students to continue of their study of these topics on their own.
Dzurisin, D.; Poland, Michael P.; Burgmann, R.
2002-01-01
Leveling surveys of a 193-km circuit across Medicine Lake volcano (MLV) in 1954 and 1989 show that the summit area subsided by as much as 302 ?? 30 mm (-8.6 ?? 0.9 mm/yr) with respect to a datum point near Bartle, California, 40 km to the southwest. This result corrects an error in the earlier analysis of the same data by Dzurisin et al. [1991], who reported the subsidence rate as -11.1 ?? 1.2 mm/yr. The subsidence pattern extends across the entire volcano, with a surface area of nearly 2000 km2. Two areas of localized subsidence by as much as 20 cm can be attributed to shallow normal faulting near the volcano's periphery. Surveys of an east-west traverse across Lava Beds National Monument on the north flank of the volcano in 1990 and of a 23-km traverse across the summit area in 1999 show that subsidence continued at essentially the same rate during 1989-1999 as 1954-1989. Volcano-wide subsidence can be explained by either a point source of volume loss (Mogi) or a contracting horizontal rectangular dislocation (sill) at a depth of 10-11 km. Volume loss rate estimates range from 0.0013 to 0.0032 km3/yr, depending mostly on the source depth estimate and source type. Based on first-order quantitative considerations, we can rule out that the observed subsidence is due to volume loss from magma withdrawal, thermal contraction, or crystallizing magma at depth. Instead, we attribute the subsidence and faulting to: (1 gravitational loading of thermally weakened crust by the mass of the volcano and associated intrusive rocks, and (2) thinning of locally weakened crust by Basin and Range deformation. The measured subsidence rate exceeds long-term estimates from drill hole data, suggesting that over long timescales, steady subsidence and episodic uplift caused by magmatic intrusions counteract each other to produce the lower net subsidence rate.
Automating the selection of standard parallels for conic map projections
NASA Astrophysics Data System (ADS)
Šavriǒ, Bojan; Jenny, Bernhard
2016-05-01
Conic map projections are appropriate for mapping regions at medium and large scales with east-west extents at intermediate latitudes. Conic projections are appropriate for these cases because they show the mapped area with less distortion than other projections. In order to minimize the distortion of the mapped area, the two standard parallels of conic projections need to be selected carefully. Rules of thumb exist for placing the standard parallels based on the width-to-height ratio of the map. These rules of thumb are simple to apply, but do not result in maps with minimum distortion. There also exist more sophisticated methods that determine standard parallels such that distortion in the mapped area is minimized. These methods are computationally expensive and cannot be used for real-time web mapping and GIS applications where the projection is adjusted automatically to the displayed area. This article presents a polynomial model that quickly provides the standard parallels for the three most common conic map projections: the Albers equal-area, the Lambert conformal, and the equidistant conic projection. The model defines the standard parallels with polynomial expressions based on the spatial extent of the mapped area. The spatial extent is defined by the length of the mapped central meridian segment, the central latitude of the displayed area, and the width-to-height ratio of the map. The polynomial model was derived from 3825 maps-each with a different spatial extent and computationally determined standard parallels that minimize the mean scale distortion index. The resulting model is computationally simple and can be used for the automatic selection of the standard parallels of conic map projections in GIS software and web mapping applications.
Dual-plane ultrasound flow measurements in liquid metals
NASA Astrophysics Data System (ADS)
Büttner, Lars; Nauber, Richard; Burger, Markus; Räbiger, Dirk; Franke, Sven; Eckert, Sven; Czarske, Jürgen
2013-05-01
An ultrasound measurement system for dual-plane, two-component flow velocity measurements especially in opaque liquids is presented. Present-day techniques for measuring local flow structures in opaque liquids disclose considerable drawbacks concerning line-wise measurement of single ultrasound probes. For studying time-varying flow patterns, conventional ultrasound techniques are either limited by time-consuming mechanical traversing or by the sequential operation of single probes. The measurement system presented within this paper employs four transducer arrays with a total of 100 single elements which allows for flow mapping without mechanical traversing. A high frame rate of several 10 Hz has been achieved due to an efficient parallelization scheme using time-division multiplexing realized by a microcontroller-based electronic switching matrix. The functionality and capability of the measurement system are demonstrated on a liquid metal flow at room temperature inside a cube driven by a rotating magnetic field (RMF). For the first time, the primary and the secondary flow have been studied in detail and simultaneously using a configuration with two crossed measurement planes. The experimental data confirm predictions made by numeric simulation. After a sudden switching on of the RMF, inertial oscillations of the secondary flow were observed by means of a time-resolved measurement with a frame rate of 3.4 Hz. The experiments demonstrate that the presented measurement system is able to investigate complex and transient flow structures in opaque liquids. Due to its ability to study the temporal evolution of local flow structures, the measurement system could provide considerable progress for fluid dynamics research, in particular for applications in the food industry or liquid metal technologies.
Recent studies of time variations of natural electromagnetic fields in Scotland
NASA Astrophysics Data System (ADS)
Hutton, V. R. S.; Dawes, G.; Ingham, M.; Kirkwood, S.; Mbipom, E. W.; Sik, J.
1981-01-01
A series of geomagnetic induction studies has been undertaken in Scotland since 1973. It includes the operation of two geomagnetic arrays, one over northern Scotland and the other over southern Scotland, subsequent individual station and small-scale geomagnetic array studies, and three sets of magnetotelluric soundings which traverse Scotland from the Lewisian Foreland to the English border. The problems associated with the interpretation of induction data from an island located in the subauroral region are discussed qualitatively and the manner in which both coast and source field effects can be accounted for, is described. The geomagnetic deep sounding data (GDS) from all the observation sites have been collated, and examples of hypothetical event contour maps and traverses across the Great Glen and of individual events from the northern array are presented. They indicate that significant lateral variations in electrical conductivity structure within the crust and upper mantle are associated with the major geological faults in the region. Examples of the results of the magnetotelluric soundings are also presented, together with an outline of the procedure used for one- and two-dimensional modelling. Models of the geo-electric structure in both northern and southern Scotland have been obtained. These show distinctive features which are compatible with the qualitative interpretation of the magnetovariational data. For example, the major granitic blocks are highly resistive while regions of relatively low resistivity exist at upper crustal depths near the Great Glen, Highland boundary and Southern Uplands faults. A zone of low resistivity exists at lower crust-uppermost mantle depths throughout much of the region, the lowest value occurring under the Southern Uplands.
The mechanism of nucleosome traversal by RNA polymerase II
2011-01-01
RNA polymerase II traverses nucleosomes rapidly and efficiently in the cell but it has not been possible to duplicate this process in the test tube. A single nucleosome has generally been found to provide a strong barrier to transcript elongation in vitro. Recent studies have shown that effective transcript elongation can occur on nucleosomal templates in vitro, but this depends on both facilitated uncoiling of DNA from the octamer surface and the presence of transcription factors that maintain polymerase in the transcriptionally competent state. These findings indicate that the efficiency and rate of transcription through chromatin could be regulated through controlled DNA uncoiling. These studies also demonstrate that nucleosome traversal need not result in nucleosome displacement. PMID:21519186
Łazińska, Magdalena; Durejko, Tomasz; Czujko, Tomasz; Bojar, Zbigniew
2018-05-14
The results of the fabrication of components made with Fe-30%Al-0.35%Zr-0.1%B alloy powder using the Laser Engineered Net Shaping (LENS TM ) system operated at different traverse feed rates are described in this paper. The temperature of the molten metal pool was recorded during this process. Depending on the assumed feed rate, the formation of Zr⁻based precipitates with various morphologies and distributions was observed in the structure of the investigated material. It was found that as the traverse speed increased, spheroidization, refinement, and a more homogeneous distribution of these precipitates occurred.
NASA Technical Reports Server (NTRS)
Farrand, W. H.; Johnson, J. R.; Bell, J. F., III; Mittlefehldt, D. W.; Gellert, R.; VanBommel, S.; Arvidson, R. E.; Schroder, C.
2017-01-01
The Mars Exploration Rover Opportunity has concluded its exploration of Marathon Valley, a 100-meter-wide valley in the western rim of the 22-kilometer-diameter Endeavour crater. Orbital observations from CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) indicated the presence of Fe smectites in Marathon Valley. Since leaving the valley, Opportunity has been traversing along the inner rim of the crater, and currently towards the outer rim. This presentation describes the Pancam 430 to 1009 nanometer (VNIR - Visible and Near Infared) multispectral reflectance and APXS (Alpha Particle X-ray Spectrometer) chemical compositions of rock and soil units observed during the latter portions of the Marathon Valley campaign on the Knudson Ridge area and observations of those materi-als along the traverse to the south. Full Pancam spectral coverage of rock targets consists of 13 filter (13f) data collections with 11 spectrally unique channels with data processing. Data were examined using spectral parameters, decorrelation stretch composites, and spectral mixture analysis. Note that color terms used here refer to colors in various false-color renditions, not true colors. The APXS determines major and select trace element compositions of targets.
Winter sky brightness and cloud cover at Dome A, Antarctica
NASA Astrophysics Data System (ADS)
Moore, Anna M.; Yang, Yi; Fu, Jianning; Ashley, Michael C. B.; Cui, Xiangqun; Feng, Long Long; Gong, Xuefei; Hu, Zhongwen; Lawrence, Jon S.; Luong-Van, Daniel M.; Riddle, Reed; Shang, Zhaohui; Sims, Geoff; Storey, John W. V.; Tothill, Nicholas F. H.; Travouillon, Tony; Wang, Lifan; Yang, Huigen; Yang, Ji; Zhou, Xu; Zhu, Zhenxi
2013-01-01
At the summit of the Antarctic plateau, Dome A offers an intriguing location for future large scale optical astronomical observatories. The Gattini Dome A project was created to measure the optical sky brightness and large area cloud cover of the winter-time sky above this high altitude Antarctic site. The wide field camera and multi-filter system was installed on the PLATO instrument module as part of the Chinese-led traverse to Dome A in January 2008. This automated wide field camera consists of an Apogee U4000 interline CCD coupled to a Nikon fisheye lens enclosed in a heated container with glass window. The system contains a filter mechanism providing a suite of standard astronomical photometric filters (Bessell B, V, R) and a long-pass red filter for the detection and monitoring of airglow emission. The system operated continuously throughout the 2009, and 2011 winter seasons and part-way through the 2010 season, recording long exposure images sequentially for each filter. We have in hand one complete winter-time dataset (2009) returned via a manned traverse. We present here the first measurements of sky brightness in the photometric V band, cloud cover statistics measured so far and an estimate of the extinction.
NASA Astrophysics Data System (ADS)
Schack, P.; Hirt, C.; Hauk, M.; Featherstone, W. E.; Lyon, T. J.; Guillaume, S.
2018-01-01
We present results from a new vertical deflection (VD) traverse observed in Perth, Western Australia, which is the first of its kind in the Southern Hemisphere. A digital astrogeodetic QDaedalus instrument was deployed to measure VDs with {˜ } 0.2'' precision at 39 benchmarks with a {{˜ }}1 km spacing. For the conversion of VDs to quasigeoid height differences, the method of astronomical-topographical levelling was applied, based on topographical information from the Shuttle Radar Topography Mission. The astronomical quasigeoid heights are in 20-30 mm (RMS) agreement with three independent gravimetric quasigeoid models, and the astrogeodetic VDs agree to 0.2-0.3'' (north-south) and 0.6-0.9'' (east-west) RMS. Tilt-like biases of {˜ }1 mm over {˜ }1 km are present for all quasigeoid models within {˜ }20 km of the coastline, suggesting inconsistencies in the coastal zone gravity data. The VD campaign in Perth was designed as a low-cost effort, possibly allowing replication in other Southern Hemisphere countries (e.g., Asia, Africa, South America and Antarctica), where VD data are particularly scarce.
D.R.O.P: The Durable Reconnaissance and Observation Platform
NASA Technical Reports Server (NTRS)
McKenzie, Clifford; Parness, Aaron
2011-01-01
Robots can provide a remote presence in areas that are either inaccessible or too dangerous for humans. However, robots are often limited by their ability to adapt to the terrain or resist environmental factors. The Durable Reconnaissance and Observation Platform (DROP) is a lightweight robot that addresses these challenges with the capability to survive falls from significant heights, carry a useable payload, and traverse a variety of surfaces, including climbing vertical surfaces like wood, stone, and concrete. DROP is manufactured using a combination of rapid prototyping and shape deposition manufacturing. It uses microspine technology to create a new wheel-like design for vertical climbing. To date, DROP has successfully engaged several vertical surfaces, hanging statically without assistance, and traversed horizontal surfaces at approximately 30 cm/s. Unassisted vertical climbing is capable on surfaces up to 85deg at a rate of approximately 25cm*s(sup -1). DROP can also survive falls from up to 3 meters and has the ability to be thrown off of and onto rooftops. Future efforts will focus on improving the microspine wheels, selecting more resilient materials, customizing the controls, and performing more rigorous and quantifiable testing.
Heritable non-lethal damage to cultured human cells irradiated with heavy ions.
Walker, James T; Todd, Paul; Walker, Olivia A
2002-12-01
During interplanetary flights the nuclei of all of a crew member's cells could be traversed by at least one high-LET (Linear Energy Transfer) cosmic-ray particle. In mammalian cells irradiated in vitro about 1 in 10,000 of the surviving cells traversed by heavy particles is transformed to malignancy or mutated. What, if anything, happens to the remaining >99% of surviving cells? A retrospective analysis of archived data and samples from heavy-ion irradiation experiments with cultured human cells in vitro indicated that heavy ions caused a dose- and LET-dependent reduction in growth rates of progeny of irradiated cells, based on colony-size distributions. The maximum action cross section for this effect is between 100 and 300 microm2, at least as large as the cell nuclear area and up to 3 times the cross section for cell killing. Thus, heritable slow growth is the most prevalent effect of high-LET radiations on cultured animal cells, which may have implications for crew health during deep space travel. The views expressed in this article are those of the author(s) and do not necessarily reflect the views or policies of the USEPA.
Human Mars Surface Science Operations
NASA Technical Reports Server (NTRS)
Bobskill, Marianne R.; Lupisella, Mark L.
2014-01-01
Human missions to the surface of Mars will have challenging science operations. This paper will explore some of those challenges, based on science operations considerations as part of more general operational concepts being developed by NASA's Human Spaceflight Architecture (HAT) Mars Destination Operations Team (DOT). The HAT Mars DOT has been developing comprehensive surface operations concepts with an initial emphasis on a multi-phased mission that includes a 500-day surface stay. This paper will address crew science activities, operational details and potential architectural and system implications in the areas of (a) traverse planning and execution, (b) sample acquisition and sample handling, (c) in-situ science analysis, and (d) planetary protection. Three cross-cutting themes will also be explored in this paper: (a) contamination control, (b) low-latency telerobotic science, and (c) crew autonomy. The present traverses under consideration are based on the report, Planning for the Scientific Exploration of Mars by Humans1, by the Mars Exploration Planning and Analysis Group (MEPAG) Human Exploration of Mars-Science Analysis Group (HEM-SAG). The traverses are ambitious and the role of science in those traverses is a key component that will be discussed in this paper. The process of obtaining, handling, and analyzing samples will be an important part of ensuring acceptable science return. Meeting planetary protection protocols will be a key challenge and this paper will explore operational strategies and system designs to meet the challenges of planetary protection, particularly with respect to the exploration of "special regions." A significant challenge for Mars surface science operations with crew is preserving science sample integrity in what will likely be an uncertain environment. Crewed mission surface assets -- such as habitats, spacesuits, and pressurized rovers -- could be a significant source of contamination due to venting, out-gassing and cleanliness levels associated with crew presence. Low-latency telerobotic science operations has the potential to address a number of contamination control and planetary protection issues and will be explored in this paper. Crew autonomy is another key cross-cutting challenge regarding Mars surface science operations, because the communications delay between earth and Mars could as high as 20 minutes one way, likely requiring the crew to perform many science tasks without direct timely intervention from ground support on earth. Striking the operational balance between crew autonomy and earth support will be a key challenge that this paper will address.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1983-01-01
This volume contains eight appendices: flight line maps, geology maps, explanation of geologic legend, flight line/geology maps, radiometric contour maps, magnetic contour maps, multi-variant analysis maps, and geochemical factor analysis maps. These appendices pertain to the Durango B detail area.
Artist's concept of Hadley-Apennine landing site with LRV traverses outlined
NASA Technical Reports Server (NTRS)
1971-01-01
An artist's concept of the Hadley-Apennine landing site, depicting the traverses planned on the Apollo 15 lunar landing mission using the Lunar Roving Vehicle (LRV). The Roman numerals indicate the three periods of extravehicular activity (EVA). The Arabic numbers represent the station stops. Art work by Jerry Elmore.
An Analysis of Special Operations Command - South’s Distributive Command and Control Concept
2007-12-01
Special Ops aviation unit traverses Bermuda Triangle en route to new home”, News Service Release Number 03082525 (August 2003), http://news.soc.mil...7, 2007). U.S. Army Special Operations Command. “Special Ops Aviation Unit Traverses Bermuda Triangle En Route to New Home.” News Service Release
75 FR 53334 - Notice of Filing of Plats of Survey; Montana
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-31
... River, downstream, through sections 7 and 18, a portion of the subdivision of sections 7 and 18, a... present left bank of the Missouri River and informative traverse, downstream, through sections 7 and 18, the limits of erosion and informative traverse, downstream through sections 7 and 18 and certain...
Measurement of vortex flow fields
NASA Technical Reports Server (NTRS)
Mcdevitt, T. Kevin; Ambur, Todd A.; Orngard, Gary M.; Owen, F. Kevin
1992-01-01
A 3-D laser fluorescence anemometer (LFA) was designed, built, and demonstrated for use in the Langley 16 x 24 inch Water Tunnel. Innovative optical design flexibility combined with compact and portable data acquisition and control systems were incorporated into the instrument. This will allow its use by NASA in other test facilities. A versatile fiber optic system facilities normal and off-axis laser beam alignment, removes mirror losses and improves laser safety. This added optical flexibility will also enable simple adaptation for use in the adjacent jet facility. New proprietary concepts in transmitting color separation, light collection, and novel prism separation of the scattered light was also designed and built into the system. Off-axis beam traverse and alignment complexity led to the requirement for a specialized, programmable transverse controller, and the inclusion of an additional traverse for the off-axis arm. To meet this challenge, an 'in-house' prototype unit was designed and built and traverse control software developed specifically for the water tunnel traverse applications. A specialized data acquisition interface was also required. This was designed and built for the LFA system.
NASA Astrophysics Data System (ADS)
Paidar, Moslem; Asgari, Ali; Ojo, Olatunji Oladimeji; Saberi, Abbas
2018-03-01
Grain growth inhibition at the heat-affected zone, improved weld strength and superior tribological properties of welds are desirable attributes of modern manufacturing. With the focused on these attributes, tungsten carbide (WC) nanoparticles were employed as reinforcements for the friction stir welding of 5-mm-thick AA5182 aluminum alloy by varying tool traverse speeds. The microstructure, microhardness, ultimate tensile strength, fracture and wear behavior of the resultant WC-reinforced welds were investigated, while unreinforced AA5182 welds were employed as controls for the study. The result shows that the addition of WC nanoparticles causes substantial grain refinement within the weld nugget. A decrease in traverse speed caused additional particle fragmentation, improved hardness value and enhanced weld strength in the reinforced welds. Improved wear rate and friction coefficient of welds were attained at a reduced traverse speed of 100 mm/min in the WC-reinforced welds. This improvement is attributed to the effects of reduced grain size/grain fragmentation and homogeneous dispersion of WC nanoparticles within the WC-reinforced weld nugget.
NASA Technical Reports Server (NTRS)
Bon, Bruce; Seraji, Homayoun
2007-01-01
Rover Graphical Simulator (RGS) is a package of software that generates images of the motion of a wheeled robotic exploratory vehicle (rover) across terrain that includes obstacles and regions of varying traversability. The simulated rover moves autonomously, utilizing reasoning and decision-making capabilities of a fuzzy-logic navigation strategy to choose its path from an initial to a final state. RGS provides a graphical user interface for control and monitoring of simulations. The numerically simulated motion is represented as discrete steps with a constant time interval between updates. At each simulation step, a dot is placed at the old rover position and a graphical symbol representing the rover is redrawn at the new, updated position. The effect is to leave a trail of dots depicting the path traversed by the rover, the distances between dots being proportional to the local speed. Obstacles and regions of low traversability are depicted as filled circles, with buffer zones around them indicated by enclosing circles. The simulated robot is equipped with onboard sensors that can detect regional terrain traversability and local obstacles out to specified ranges. RGS won the NASA Group Achievement Award in 2002.
Huang, Luoxiu; Chen, Xin; Shou, Tiande
2004-02-20
The feedback effect of activity of area 21a on orientation maps of areas 17 and 18 was investigated in cats using intrinsic signal optical imaging. A spatial frequency-dependent decrease in response amplitude of orientation maps to grating stimuli was observed in areas 17 and 18 when area 21a was inactivated by local injection of GABA, or by a lesion induced by liquid nitrogen freezing. The decrease in response amplitude of orientation maps of areas 17 and 18 after the area 21a inactivation paralleled the normal response without the inactivation. Application in area 21a of bicuculline, a GABAa receptor antagonist caused an increase in response amplitude of orientation maps of area 17. The results indicate a positive feedback from high-order visual cortical area 21a to lower-order areas underlying a spatial frequency-dependent mechanism.
Method and apparatus for monitoring the power of a laser beam
Paris, R.D.; Hackel, R.P.
1996-02-06
A method for monitoring the power of a laser beam in real time is disclosed. At least one optical fiber is placed through the laser beam, where a portion of light from the laser beam is coupled into the optical fiber. The optical fiber may be maintained in a stationary position or moved periodically over a cross section of the laser beam to couple light from each area traversed. Light reaching both fiber ends is monitored according to frequency and processed to determine the power of the laser beam. 6 figs.
Wave propagation and earth satellite radio emission studies
NASA Technical Reports Server (NTRS)
Yeh, K. C.; Liu, C. H.; Flaherty, B. J.
1974-01-01
Radio propagation studies of the ionosphere using satellite radio beacons are described. The ionosphere is known as a dispersive, inhomogeneous, irregular and sometimes even nonlinear medium. After traversing through the ionosphere the radio signal bears signatures of these characteristics. A study of these signatures will be helpful in two areas: (1) It will assist in learning the behavior of the medium, in this case the ionosphere. (2) It will provide information of the kind of signal characteristics and statistics to be expected for communication and navigational satellite systems that use the similar geometry.
Alahautala, Taito; Hernberg, Rolf
2004-02-01
Uniform illumination was generated by use of a large number of diode laser emitters and a single nonimaging paraboloid with a Lambertian scatterer in the truncation plane. Laser light traverses a path toward the Lambertian surface and back by total internal reflection. An overall efficiency of 69% was demonstrated. Improvements that would increase the efficiency to more than 85% are suggested. The illuminated area is circular, with 14-mm diameter. The spatial nonuniformity of the beam profile is less than +/- 2%.
Earth observations taken from the shuttle Challenger during STS-41C
2009-06-25
41C-31-990 (6-13 April 1984) --- Southwestern Algeria's Erg Chech shows long lines of parallel sand dunes called siefs. The Erg (sand desert) is in a remote (26.5 degrees north by 1.5 degrees west) of harsh desert, uninhabited and rarely visited. These parallel sand dunes are about 100 miles in length and 5 to 10 miles apart and are found in very few areas of the Earth. Most sand dunes are traverse dunes, or perpendicular to the general direction of the wind.
Method and apparatus for monitoring the power of a laser beam
Paris, Robert D.; Hackel, Richard P.
1996-01-01
A method for monitoring the power of a laser beam in real time is disclosed. At least one optical fiber is placed through the laser beam, where a portion of light from the laser beam is coupled into the optical fiber. The optical fiber may be maintained in a stationary position or moved periodically over a cross section of the laser beam to couple light from each area traversed. Light reaching both fiber ends is monitored according to frequency and processed to determine the power of the laser beam.
Contamination Mitigation Strategies for Long Duration Human Spaceflight Missions
NASA Technical Reports Server (NTRS)
Lewis, Ruthan; Lupisella, Mark; Bleacher, Jake; Farrell, William
2017-01-01
Contamination control issues are particularly challenging for long-term human spaceflight and are associated with the search for life, dynamic environmental conditions, human-robotic-environment interaction, sample collection and return, biological processes, waste management, long-term environmental disturbance, etc. These issues impact mission success, human health, planetary protection, and research and discovery. Mitigation and control techniques and strategies may include and integrate long-term environmental monitoring and reporting, contamination control and planetary protection protocols, habitation site design, habitat design, and surface exploration and traverse pathways and area access planning.
1995-04-01
carbon dioxide, methane, and freons, are steadily increasing due to human activities. For example, carbon dioxide is produced by the burning of fossil ...shipping would remain approximately 35-45 km distant. It is so far offshore that only the incidental pleasurecraft or fishing boats traverse the area...the boat from which the source is deployed, and unless the boat can remain stationary for a long period of time prior to commencement of the
Redman, W.C.; Shonka, F.R.
1958-02-18
This patent describes a novel ionization chamber which is well suited to measuring the radioactivity of the various portions of a wire as the wire is moved at a uniform speed, in order to produce the neutron flux traverse pattern of a reactor in which the wire was previously exposed to neutron radiation. The ionization chamber of the present invention is characterized by the construction wherein the wire is passed through a tubular, straight electrode and radiation shielding material is disposed along the wire except at an intermediate, narrow area where the second electrode of the chamber is located.
NASA Technical Reports Server (NTRS)
Crumpler, L. S.; Arvidson, R. E.; Farrand, W. H.; Golombek, M. P.; Grant, J. A.; Ming, D. W.; Mittlefehldt, D. W.; Parker, T. J.
2015-01-01
Mars Exploration Rover Opportunity traversed 7.9 km and 27 degrees of arc along the rim of the 22 km-diameter Noachian "Endeavour" impact crater since its arrival 1200 sols ago. Areas of aqueous and low-grade thermal alteration, and changes in structure, attitude, and macroscopic texture of outcrops are notable across several discontinuities between segments of the crater rim. The discontinuities and other post-impact joints and fractures coincide with sites of apparent deep fluid circulation processes responsible for thermal and chemical alteration of local outcrops.
NASA Technical Reports Server (NTRS)
Carsey, Frank; Behar, Alberto
2004-01-01
We have continued to develop a concept for use of autonomous rovers, originally developed for use in planetary exploration, in polar science on Earth; the concept was the subject of a workshop, and this report summarizes and extends that workshop. The workshop on Antarctic Autonomous Scientific Vehicles and Traverses met at the National Geographic Society on February 14 and 15, 2001 to discuss scientific objectives and benefits of the use of autonomous rovers. The participants enthusiastically viewed rovers as being uniquely valuable for such tasks as data taking on tedious or repetitive routes, traverses in polar night, difficult or hazardous routes, extremely remote regions, routes requiring only simple instrumentation, traverses that must be conducted at low speed, augments of manned traverses, and scientific procedures not compatible with human presence or combustion engines. The workshop has concluded that instrumented autonomous vehicles, of the type being developed for planetary exploration, have the potential to contribute significantly to the way science in conducted in Antarctica while also aiding planetary technology development, and engaging the public's interest. Specific objectives can be supported in understanding ice sheet mass balance, sea ice heat and momentum exchange, and surface air chemistry processes. In the interval since the workshop, we have concluded that organized program to employ such rovers to perform scientific tasks in the Fourth International Polar Year would serve the objectives of that program well.
Autonomous Rovers for Polar Science Campaigns
NASA Astrophysics Data System (ADS)
Lever, J. H.; Ray, L. E.; Williams, R. M.; Morlock, A. M.; Burzynski, A. M.
2012-12-01
We have developed and deployed two over-snow autonomous rovers able to conduct remote science campaigns on Polar ice sheets. Yeti is an 80-kg, four-wheel-drive (4WD) battery-powered robot with 3 - 4 hr endurance, and Cool Robot is a 60-kg 4WD solar-powered robot with unlimited endurance during Polar summers. Both robots navigate using GPS waypoint-following to execute pre-planned courses autonomously, and they can each carry or tow 20 - 160 kg instrument payloads over typically firm Polar snowfields. In 2008 - 12, we deployed Yeti to conduct autonomous ground-penetrating radar (GPR) surveys to detect hidden crevasses to help establish safe routes for overland resupply of research stations at South Pole, Antarctica, and Summit, Greenland. We also deployed Yeti with GPR at South Pole in 2011 to identify the locations of potentially hazardous buried buildings from the original 1950's-era station. Autonomous surveys remove personnel from safety risks posed during manual GPR surveys by undetected crevasses or buried buildings. Furthermore, autonomous surveys can yield higher quality and more comprehensive data than manual ones: Yeti's low ground pressure (20 kPa) allows it to cross thinly bridged crevasses or other voids without interrupting a survey, and well-defined survey grids allow repeated detection of buried voids to improve detection reliability and map their extent. To improve survey efficiency, we have automated the mapping of detected hazards, currently identified via post-survey manual review of the GPR data. Additionally, we are developing machine-learning algorithms to detect crevasses autonomously in real time, with reliability potentially higher than manual real-time detection. These algorithms will enable the rover to relay crevasse locations to a base station for near real-time mapping and decision-making. We deployed Cool Robot at Summit Station in 2005 to verify its mobility and power budget over Polar snowfields. Using solar power, this zero-emissions rover could travel more than 500 km per week during Polar summers and provide 100 - 200 W to power instrument payloads to help investigate the atmosphere, magnetosphere, glaciology and sub-glacial geology in Antarctica and Greenland. We are currently upgrading Cool Robot's navigation and solar-power systems and will deploy it during 2013 to map the emissions footprint around Summit Station to demonstrate its potential to execute long-endurance Polar science campaigns. These rovers could assist science traverses to chart safe routes into the interior of Antarctica and Greenland or conduct autonomous, remote science campaigns to extend spatial and temporal coverage for data collection. Our goals include 1,000 - 2,000-km summertime traverses of Antarctica and Greenland, safe navigation through 0.5-m amplitude sastrugi fields, survival in blizzards, and rover-network adaptation to research events of opportunity. We are seeking Polar scientists interested in autonomous, mobile data collection and can adapt the rovers to meet their requirements.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1983-01-01
This volume comprises eight appendices containing the following information for the Durango D detail area: flight line maps, geology maps, explanation of geologic legend, flight line/geology maps, radiometric contour maps, magnetic contour maps, multi-variant analysis maps, and geochemical factor analysis maps.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1983-01-01
This volume comprises eight appendices containing the following information for the Durango C detail area: flight line maps, geology maps, explanation of geologic legend, flight line/geology maps, radiometric contour maps, magnetic contour maps, multi-variant analysis maps, and geochemical factor analysis maps.
Custom map projections for regional groundwater models
Kuniansky, Eve L.
2017-01-01
For regional groundwater flow models (areas greater than 100,000 km2), improper choice of map projection parameters can result in model error for boundary conditions dependent on area (recharge or evapotranspiration simulated by application of a rate using cell area from model discretization) and length (rivers simulated with head-dependent flux boundary). Smaller model areas can use local map coordinates, such as State Plane (United States) or Universal Transverse Mercator (correct zone) without introducing large errors. Map projections vary in order to preserve one or more of the following properties: area, shape, distance (length), or direction. Numerous map projections are developed for different purposes as all four properties cannot be preserved simultaneously. Preservation of area and length are most critical for groundwater models. The Albers equal-area conic projection with custom standard parallels, selected by dividing the length north to south by 6 and selecting standard parallels 1/6th above or below the southern and northern extent, preserves both area and length for continental areas in mid latitudes oriented east-west. Custom map projection parameters can also minimize area and length error in non-ideal projections. Additionally, one must also use consistent vertical and horizontal datums for all geographic data. The generalized polygon for the Floridan aquifer system study area (306,247.59 km2) is used to provide quantitative examples of the effect of map projections on length and area with different projections and parameter choices. Use of improper map projection is one model construction problem easily avoided.
1972-03-02
S72-30694 (28 Jan. 1972) --- Astronauts John W. Young, left, Apollo 16 commander, and Charles M. Duke Jr., lunar module pilot, prepare to begin a simulated traverse in a training area at the Kennedy Space Center (KSC). The fifth National Aeronautics and Space Administration (NASA) Apollo lunar landing mission is scheduled to land in the mountainous highlands region near the crater Descartes to explore the area for a three-day period. Among the experiments to fly on Apollo 16 is the soil mechanics (S-200) experiment or self-recording penetrometer, a model of which is held here by Duke. A training model of the Lunar Roving Vehicle (LRV) is parked between the two crew men. Astronaut Thomas K. (Ken) Mattingly II is prime crew command module pilot for the mission.
Multisensor Modeling Underwater with Uncertain Information
1988-07-01
133 Figure 6.4: Sidescan geometry artifacts ................................ 133 Figure 6.5: Sea MARC I intensity map of Clipperton ...area ................. 136 Figure 6.6: Sea MARC I intensity map of Clipperton area (from Kasiens et al.). .. 137 Figure 6.7: Sea Beam contour map of... Clipperton area .................... 138 Figure 6.8: Sea Beam contour map of Clipperton area (from Gallo ei al.) ....... 139 Figure 6.9: Sea Beam
75 FR 54223 - Petition for Waiver of Compliance
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-03
... Measures (SSM) as follows: 1 crossing with gates and non-traversable curb medians and 1 crossing with four...-Rule Quiet Zone or in a separate Pre-Rule Quiet Zone. A SSM consisting of gates with a non-traversable... that the addition of Hubbards Lane with its SSM, results in a Quiet Zone Risk Index (QZRI) for the 6...
Apparatus for obstacle traversion
Borenstein, Johann
2004-08-10
An apparatus for traversing obstacles having an elongated, round, flexible body that includes a plurality of drive track assemblies. The plurality of drive track assemblies cooperate to provide forward propulsion wherever a propulsion member is in contact with any feature of the environment, regardless of how many or which ones of the plurality of drive track assemblies make contact with such environmental feature.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-22
..., CANCELED Kalamazoo, MI, Kalamazoo/Battle Creek Intl, RNAV (GPS) RWY 17, Amdt 1 Traverse City, MI, Cherry Capitol, GPS RWY 36, Orig-B, CANCELED Traverse City, MI, Cherry Capitol, RNAV (GPS) RWY 36, Orig Dodge..., Cassville Muni, Takeoff Minimums and Obstacle DP, Amdt 1 Fredericktown, MO, A. Paul Vance Fredericktown Rgnl...
ERIC Educational Resources Information Center
Lai, Chun
2015-01-01
Learning takes place across different social contexts, and understanding how learners perceive and traverse different learning contexts enables educators to gain a more comprehensive view of their learning processes and to support their learning better. This study examined how undergraduate foreign language learners perceived their learning…
Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-25
...-AA00 Safety Zone; National Cherry Festival Air Show and Fireworks Display, West Grand Traverse Bay... the hazards associated with fireworks displays and aircraft involved in the National Cherry Festival... Festival fireworks display and air show. At the close of the comment period, no comments were received in...
M113A1 Day/Night Movement Rate Analysis
1975-06-01
d. Each vehicle traversed the course usiig the path of the preced- ing vehicle, i.e., no " free play " in selecting a route was permitted. The test...traversed the course usling the path of the preced- ing vehicle, i.e., no " free play " in selecting a route was permitted. The test course varied from
ERIC Educational Resources Information Center
Hornberger, Nancy H.
2014-01-01
Drawing from long-term ethnographic research in the Andes, this paper examines one Quechua-speaking Indigenous bilingual educator's trajectory as she traversed (and traverses) from rural highland communities of southern Peru through development as teacher, teacher educator, researcher, and advocate for Indigenous identity and language…
Graph traversals, genes, and matroids: An efficient case of the travelling salesman problem
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gusfield, D.; Stelling, P.; Wang, Lusheng
1996-12-31
In this paper the authors consider graph traversal problems that arise from a particular technology for DNA sequencing - sequencing by hybridization (SBH). They first explain the connection of the graph problems to SBH and then focus on the traversal problems. They describe a practical polynomial time solution to the Travelling Salesman Problem in a rich class of directed graphs (including edge weighted binary de Bruijn graphs), and provide a bounded-error approximation algorithm for the maximum weight TSP in a superset of those directed graphs. The authors also establish the existence of a matroid structure defined on the set ofmore » Euler and Hamilton paths in the restricted class of graphs. 8 refs., 5 figs.« less
Effect of Varying Crustal Thickness on CHAMP Geopotential Data
NASA Technical Reports Server (NTRS)
Taylor, Patrick T.; Kis, Karoly I.; vonFrese, Ralph R. B.; Korhonen, Juha V.; Wittmann, Geza; Kim, Hyung Rae; Potts, Larmie V.
2003-01-01
Tn determine the effect of crustal thickness variation on satellite-altitude geopotential anomalies we compared two regions of Europe with vastly different values, South and Central Finland and the Pannonian Basin. In our study regions, crustal thickness exceeds 44 km in Finland and is less than 26 km in the Pannonian Basin. Heat-flow data indicate that the thinner and more active crust of the Pannonian Basin has a value nearly three times that of the Finnish Svecofennian Province. An ovoid positive CHAMP gravity anomaly (-4 mGal) is quasi-coincidental with the CHAMP magnetic anomaly traverses the Pannonian Basin while ground based gravity mapping in Hungary shows that the free-air gravity anomalies across the Pannonian Basin are near 0 to +20 mGal with shorter wavelength anomalies from +40 to less than +60 mGal and some 0 to greater than -20 mGal. Larger anomalies are detected in the mountainous areas. The minor value anomalies can indicate the isostatic equilibrium for Hungary (the central part of the Pannonian Basin). Gravity data over Finland bear overprint of de-glaciation. CHAMP gravity data indicates a west-east positive gradient of less than 4 mGal across South and Central Finland. CHAMP magnetic data (400 km) reveal elongated semi-circular negative anomalies for both regions with South-Central Finland having larger amplitude (less than -6 nT) than that over the Pannonian Basin, Hungary (less than -5 nT). In the latter subducted oceanic lithosphere has been proposed as the anomalous body.
Encoding of head direction by hippocampal place cells in bats.
Rubin, Alon; Yartsev, Michael M; Ulanovsky, Nachum
2014-01-15
Most theories of navigation rely on the concept of a mental map and compass. Hippocampal place cells are neurons thought to be important for representing the mental map; these neurons become active when the animal traverses a specific location in the environment (the "place field"). Head-direction cells are found outside the hippocampus, and encode the animal's head orientation, thus implementing a neural compass. The prevailing view is that the activity of head-direction cells is not tuned to a single place, while place cells do not encode head direction. However, little work has been done to investigate in detail the possible head-directional tuning of hippocampal place cells across species. Here we addressed this by recording the activity of single neurons in the hippocampus of two evolutionarily distant bat species, Egyptian fruit bat and big brown bat, which crawled randomly in three different open-field arenas. We found that a large fraction of hippocampal neurons, in both bat species, showed conjunctive sensitivity to the animal's spatial position (place field) and to its head direction. We introduced analytical methods to demonstrate that the head-direction tuning was significant even after controlling for the behavioral coupling between position and head direction. Surprisingly, some hippocampal neurons preserved their head direction tuning even outside the neuron's place field, suggesting that "spontaneous" extra-field spikes are not noise, but in fact carry head-direction information. Overall, these findings suggest that bat hippocampal neurons can convey both map information and compass information.
Automated map sharpening by maximization of detail and connectivity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Terwilliger, Thomas C.; Sobolev, Oleg V.; Afonine, Pavel V.
An algorithm for automatic map sharpening is presented that is based on optimization of the detail and connectivity of the sharpened map. The detail in the map is reflected in the surface area of an iso-contour surface that contains a fixed fraction of the volume of the map, where a map with high level of detail has a high surface area. The connectivity of the sharpened map is reflected in the number of connected regions defined by the same iso-contour surfaces, where a map with high connectivity has a small number of connected regions. By combining these two measures inmore » a metric termed the `adjusted surface area', map quality can be evaluated in an automated fashion. This metric was used to choose optimal map-sharpening parameters without reference to a model or other interpretations of the map. Map sharpening by optimization of the adjusted surface area can be carried out for a map as a whole or it can be carried out locally, yielding a locally sharpened map. To evaluate the performance of various approaches, a simple metric based on map–model correlation that can reproduce visual choices of optimally sharpened maps was used. The map–model correlation is calculated using a model withBfactors (atomic displacement factors; ADPs) set to zero. Finally, this model-based metric was used to evaluate map sharpening and to evaluate map-sharpening approaches, and it was found that optimization of the adjusted surface area can be an effective tool for map sharpening.« less
Automated map sharpening by maximization of detail and connectivity
Terwilliger, Thomas C.; Sobolev, Oleg V.; Afonine, Pavel V.; ...
2018-05-18
An algorithm for automatic map sharpening is presented that is based on optimization of the detail and connectivity of the sharpened map. The detail in the map is reflected in the surface area of an iso-contour surface that contains a fixed fraction of the volume of the map, where a map with high level of detail has a high surface area. The connectivity of the sharpened map is reflected in the number of connected regions defined by the same iso-contour surfaces, where a map with high connectivity has a small number of connected regions. By combining these two measures inmore » a metric termed the `adjusted surface area', map quality can be evaluated in an automated fashion. This metric was used to choose optimal map-sharpening parameters without reference to a model or other interpretations of the map. Map sharpening by optimization of the adjusted surface area can be carried out for a map as a whole or it can be carried out locally, yielding a locally sharpened map. To evaluate the performance of various approaches, a simple metric based on map–model correlation that can reproduce visual choices of optimally sharpened maps was used. The map–model correlation is calculated using a model withBfactors (atomic displacement factors; ADPs) set to zero. Finally, this model-based metric was used to evaluate map sharpening and to evaluate map-sharpening approaches, and it was found that optimization of the adjusted surface area can be an effective tool for map sharpening.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1983-01-01
An airborne combined radiometric and magnetic survey was performed for the Department of Energy (DOE) over the Durango A, Durango B, Durango C, and Durango D Detail Areas of southwestern Colorado. The Durango A Detail Area is within the coverage of the Needle Mountains and Silverton 15' map sheets, and the Pole Creek Mountain, Rio Grande Pyramid, Emerald Lake, Granite Peak, Vallecito Reservoir, and Lemon Reservoir 7.5' map sheets of the National Topographic Map Series (NTMS). The Durango B Detail Area is within the coverage of the Silverton 15' map sheet and the Wetterhorn Peak, Uncompahgre Peak, Lake City, Redcloudmore » Peak, Lake San Cristobal, Pole Creek Mountain, and Finger Mesa 7.5' map sheets of the NTMS. The Durango C Detail Area is within the coverage of the Platoro and Wolf Creek Pass 15' map sheets of the NTMS. The Durango D Detail Area is within the coverage of the Granite Lake, Cimarrona Peak, Bear Mountain, and Oakbrush Ridge 7.5' map sheets of the NTMS. Radiometric data were corrected for live time, aircraft and equipment background, cosmic background, atmospheric radon, Compton scatter, and altitude dependence. The corrected data were statistically evaluated, gridded, and contoured to produce maps of the radiometric variables, uranium, potassium, and thorium; their ratios; and the residual magnetic field. These maps have been analyzed in order to produce a multi-variant analysis contour map based on the radiometric response of the individual geological units. A geochemical analysis has been performed, using the radiometric and magnetic contour maps, the multi-variant analysis map, and factor analysis techniques, to produce a geochemical analysis map for the area.« less
Rock Abrasion as Seen by the MSL Curiosity Rover: Insights on Physical Weathering on Mars
NASA Astrophysics Data System (ADS)
Bridges, N.; Day, M. D.; Le Mouelic, S.; Martin-Torres, F. J.; Newsom, H. E.; Sullivan, R. J., Jr.; Ullan, A.; Wiens, R. C.; Zorzano, M. P.
2014-12-01
Mars is a dry planet, with actively blowing sand in many regions. In the absence of stable liquid water and an active hydrosphere, rates of chemical weathering are slow, such that aeolian abrasion is a dominant agent of landscape modification where sand is present and winds above threshold occur at sufficient frequency. Reflecting this activity, ventifacts, rocks that have been abraded by windborne particles, and wind-eroded outcrops, are common. They provide invaluable markers of the Martian wind record and insight into climate and landscape modification. Ventifacts are distributed along the traverse of the Mars Science Laboratory Curiosity rover. They contain one or more diagnostic features and textures: Facets, keels, basal sills, elongated pits, scallops/flutes, grooves, rock tails, and lineations. Keels at the junction of facets are sharp enough to pose a hazard MSL's wheels in some areas. Geomorphic and textural patterns on outcrops indicate retreat of windward faces. Moonlight Valley and other depressions are demarcated by undercut walls and scree boulders, with the valley interiors containing fewer rocks, most of which show evidence for significant abrasion. Together, this suggests widening and undercutting of the valley walls, and erosion of interior rocks, by windblown sand. HiRISE images do not show any dark sand dunes in the traverse so far, in contrast to the large dune field to the south that is migrating up to 2 m per year. In addition, ChemCam shows that the rock Bathurst has a rind rich in mobile elements that would be removed in an abrading environment. This indicates that rock abrasion was likely more dominant in the past, a hypothesis consistent with rapid scarp retreat as suggested by the cosmogenic noble gases in Yellowknife Bay. Ventifacts and evidence for bedrock abrasion have also been found at the Pathfinder, Spirit, and Opportunity sites, areas, like the Curiosity traverse so far, that lack evidence for current high sand fluxes. Yardangs are also common on the planet, regardless of whether local sand is mobile. This suggest that abrasion on Mars is an episodic process driven by the passage of sand in which rock retreat rates, based on fluxes of current active dunes, may reach 10s of microns per year. Such a process has acted, over long time scales, to imprint upon the surface a record of sand activity.
NASA Astrophysics Data System (ADS)
Ozkaya, Sait I.
2018-03-01
Fracture corridors are interconnected large fractures in a narrow sub vertical tabular array, which usually traverse entire reservoir vertically and extended for several hundreds of meters laterally. Fracture corridors with their huge conductivities constitute an important element of many fractured reservoirs. Unlike small diffuse fractures, actual fracture corridors must be mapped deterministically for simulation or field development purposes. Fracture corridors can be identified and quantified definitely with borehole image logs and well testing. However, there are rarely sufficient image logs or well tests, and it is necessary to utilize various fracture corridor indicators with varying degrees of reliability. Integration of data from many different sources, in turn, requires a platform with powerful editing and layering capability. Available commercial reservoir characterization software packages, with layering and editing capabilities, can be cost intensive. CAD packages are far more affordable and may easily acquire the versatility and power of commercial software packages with addition of a small software toolbox. The objective of this communication is to present FRACOR, a software toolbox which enables deterministic 2D fracture corridor mapping and modeling on AutoCAD platform. The FRACOR toolbox is written in AutoLISPand contains several independent routines to import and integrate available fracture corridor data from an oil field, and export results as text files. The resulting fracture corridor maps consists mainly of fracture corridors with different confidence levels from combination of static and dynamic data and exclusion zones where no fracture corridor can exist. The exported text file of fracture corridors from FRACOR can be imported into an upscaling programs to generate fracture grid for dual porosity simulation or used for field development and well planning.
NASA Astrophysics Data System (ADS)
Cerovski-Darriau, C.; Stock, J. D.
2017-12-01
Coral reef ecosystems, and the fishing and tourism industries they support, depend on clean waters. Fine sediment pollution from nearshore watersheds threatens these enterprises in West Maui, Hawai'i. To effectively mitigate sediment pollution, we first have to know where the sediment is coming from, and how fast it erodes. In West Maui, we know that nearshore sediment plumes originate from erosion of fine sand- to silt-sized air fall deposits where they are exposed by grazing, agriculture, or other disturbances. We identified and located these sediment sources by mapping watershed geomorphological processes using field traverses, historic air photos, and modern orthophotos. We estimated bank lowering rates using erosion pins, and other surface erosion rates were extrapolated from data collected elsewhere on the Hawaiian Islands. These measurements and mapping led to a reconnaissance sediment budget which showed that annual loads are dominated by bank erosion of legacy terraces. Field observations during small storms confirm that nearshore sediment plumes are sourced from bank erosion of in-stream, legacy agricultural deposits. To further verify this sediment budget, we used geochemical fingerprinting to uniquely identify each potential source (e.g. stream banks, agricultural fields, roads, other human modified soils, and hillslopes) from the Wahikuli watershed (10 km2) and analyzed the fine fraction using ICP-MS for elemental geochemistry. We propose to apply this the fingerprinting results to nearshore suspended sediment samples taken during storms to identify the proportion of sediment coming from each source. By combining traditional geomorphic mapping, monitoring and geochemistry, we hope to provide a powerful tool to verify the primary source of sediment reaching the nearshore.
Status of shallow-aquifer mapping in the Northern Front Range Area, Colorado
Robson, Stanley G.
2001-01-01
Mapping of shallow aquifers in the northern Front Range area of Colorado has been completed as part of the U.S. Geological Survey Front Range Infrastructure Resources Project. The aquifer mapping was undertaken as part of a comprehensive effort to better define the mineral, energy, cartographic, biological, and water resources that are critical to the support and development of the area's infrastructure, such as streets. highways, airports, and buildings. The aquifer mapping was undertaken in cooperation with the Colorado Division of Water Resources and the Colorado Water Conservation Board. The shallow aquifers have been mapped in a 2,450-square-mile area extending as an approximately 30-mile-wide band from north of Fort Collins to the Arapahoe-Douglas County line south of Denver (fig. I). The shallow aquifer mapping in the Denver metropolitan area was published in 1996 as Hydrologic Investigations Atlas HA-736 (Robson. 1996). Shallow aquifer mapping in the Greeley-Nunn area was published as HA-746A (Robson, Arnold, and Heiny, 2000a); mapping in the Fort Collins-Loveland area was published as HA-746B (Robson, Arnold, and Heiny, 2000b); mapping in the Fort Lupton-Gilcrest area was published as HA-746C (Robson, Heiny, and Arnold, 2000c); and mapping in the Boulder-Longmont area was published as HA-746D (Robson, Heiny, and Arnold, 2000d). Each of the five atlases contains five map sheets at 1:50,000 scale showing: 1. The thickness and extent of the unconsolidated sediments (loose gravel. sand. silt, and clay) that overlie the bedrock formations in the area (fig. 2). 2. The altitude and configuration of the bedrock surface. 3. The altitude of the water table and direction of ground-water movement. 4. The saturated thickness of the shallow aquifers. 5. The depth to the water table in the shallow aquifers.
Traversable geometric dark energy wormholes constrained by astrophysical observations
NASA Astrophysics Data System (ADS)
Wang, Deng; Meng, Xin-he
2016-09-01
In this paper, we introduce the astrophysical observations into the wormhole research. We investigate the evolution behavior of the dark energy equation of state parameter ω by constraining the dark energy model, so that we can determine in which stage of the universe wormholes can exist by using the condition ω <-1. As a concrete instance, we study the Ricci dark energy (RDE) traversable wormholes constrained by astrophysical observations. Particularly, we find from Fig. 5 of this work, when the effective equation of state parameter ω _X<-1 (or z<0.109), i.e., the null energy condition (NEC) is violated clearly, the wormholes will exist (open). Subsequently, six specific solutions of statically and spherically symmetric traversable wormhole supported by the RDE fluids are obtained. Except for the case of a constant redshift function, where the solution is not only asymptotically flat but also traversable, the five remaining solutions are all non-asymptotically flat, therefore, the exotic matter from the RDE fluids is spatially distributed in the vicinity of the throat. Furthermore, we analyze the physical characteristics and properties of the RDE traversable wormholes. It is worth noting that, using the astrophysical observations, we obtain the constraints on the parameters of the RDE model, explore the types of exotic RDE fluids in different stages of the universe, limit the number of available models for wormhole research, reduce theoretically the number of the wormholes corresponding to different parameters for the RDE model, and provide a clearer picture for wormhole investigations from the new perspective of observational cosmology.
Microgravity and Electrical Resistivity Techniques for Detection of Caves and Clandestine Tunnels
NASA Astrophysics Data System (ADS)
Crawford, N. C.; Croft, L. A.; Cesin, G. L.; Wilson, S.
2006-05-01
The Center for Cave and Karst Studies, CCKS, has been using microgravity to locate caves from the ground's surface since 1985. The geophysical subsurface investigations began during a period when explosive and toxic vapors were rising from the karst aquifer under Bowling Green into homes, businesses, and schools. The USEPA provided the funding for this Superfund Emergency, and the CCKS was able to drill numerous wells into low-gravity anomalies to confirm and even map the route of caves in the underlying limestone bedrock. In every case, a low-gravity anomaly indicated a bedrock cave, a cave with a collapsed roof or locations where a bedrock cave had collapsed and filled with alluvium. At numerous locations, several wells were cored into microgravity anomalies and in every case, additional wells were drilled on both sides of the anomalies to confirm that the technique was in fact reliable. The wells cored on both sides of the anomalies did not intersect caves but instead intersected virtually solid limestone. Microgravity also easily detected storm sewers and even sanitary sewers, sometimes six meters (twenty feet) beneath the surface. Microgravity has also been used on many occasions to investigate sinkhole collapses. It identified potential collapse areas by detecting voids in the unconsolidated material above bedrock. The system will soon be tested over known tunnels and then during a blind test along a section of the U.S. border at Nogales, Arizona. The CCKS has experimented with other geophysical techniques, particularly ground penetrating radar, seismic and electrical resistivity. In the late 1990s the CCKS started using the Swift/Sting resistivity meter to perform karst geophysical subsurface investigations. The system provides good depth to bedrock data, but it is often difficult to interpret bedrock caves from the modeled data. The system typically used now by the CCKS to perform karst subsurface investigations is to use electrical resistivity traverses followed by microgravity over suspect areas identified on the modeled resistivity data. Some areas of high resistivity indicate caves, but others simply indicate pockets of dry limestone, and the signatures looks virtually identical. Therefore, the CCKS performs microgravity over all suspect areas along the resistivity traverses. A low-gravity anomaly that corresponds with a high-resistivity anomaly indicates a cave location. A high-resistivity anomaly that does not also have a low- gravity anomaly indicates a pocket of dry limestone. Numerous cored wells have been drilled both into the anomalies and on both sides to confirm the cave locations and to establish that the technique is accurate. The September 11, 2001 World Trade Center catastrophe was the catalyst for the formation of a program within the CCKS to use the techniques for locating bedrock caves and voids in unconsolidated materials for search and rescue and for locating clandestine tunnels. We are now into our third year of a grant from the Kentucky Science and Technology Center to develop a robot that will measure microgravity and other geophysical techniques. The robot has the potential for detecting clandestine tunnels under the U.S. border as well as military applications. The system will soon be tested over known tunnels and then during a blind test along a section of the U.S. border at Nogales, Arizona.
Geologic Map and Map Database of Eastern Sonoma and Western Napa Counties, California
Graymer, R.W.; Brabb, E.E.; Jones, D.L.; Barnes, J.; Nicholson, R.S.; Stamski, R.E.
2007-01-01
Introduction This report contains a new 1:100,000-scale geologic map, derived from a set of geologic map databases (Arc-Info coverages) containing information at 1:62,500-scale resolution, and a new description of the geologic map units and structural relations in the map area. Prepared as part of the San Francisco Bay Region Mapping Project, the study area includes the north-central part of the San Francisco Bay region, and forms the final piece of the effort to generate new, digital geologic maps and map databases for an area which includes Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Santa Cruz, Solano, and Sonoma Counties. Geologic mapping in Lake County in the north-central part of the map extent was not within the scope of the Project. The map and map database integrates both previously published reports and new geologic mapping and field checking by the authors (see Sources of Data index map on the map sheet or the Arc-Info coverage eswn-so and the textfile eswn-so.txt). This report contains new ideas about the geologic structures in the map area, including the active San Andreas Fault system, as well as the geologic units and their relations. Together, the map (or map database) and the unit descriptions in this report describe the composition, distribution, and orientation of geologic materials and structures within the study area at regional scale. Regional geologic information is important for analysis of earthquake shaking, liquifaction susceptibility, landslide susceptibility, engineering materials properties, mineral resources and hazards, as well as groundwater resources and hazards. These data also assist in answering questions about the geologic history and development of the California Coast Ranges.
Apollo scientific experiments data handbook
NASA Technical Reports Server (NTRS)
Eichelman, W. F. (Editor); Lauderdale, W. W. (Editor)
1974-01-01
A brief description of each of the Apollo scientific experiments was described, together with its operational history, the data content and formats, and the availability of the data. The lunar surface experiments described are the passive seismic, active seismic, lunar surface magnetometer, solar wind spectrometer, suprathermal ion detector, heat flow, charged particle, cold cathode gage, lunar geology, laser ranging retroreflector, cosmic ray detector, lunar portable magnetometer, traverse gravimeter, soil mechanics, far UV camera (lunar surface), lunar ejecta and meteorites, surface electrical properties, lunar atmospheric composition, lunar surface gravimeter, lunar seismic profiling, neutron flux, and dust detector. The orbital experiments described are the gamma-ray spectrometer, X-ray fluorescence, alpha-particle spectrometer, S-band transponder, mass spectrometer, far UV spectrometer, bistatic radar, IR scanning radiometer, particle shadows, magnetometer, lunar sounder, and laser altimeter. A brief listing of the mapping products available and information on the sample program were also included.
Total Solar Eclipse of 1999 August 11
NASA Technical Reports Server (NTRS)
Espenak, Fred; Anderson, Jay
1997-01-01
On 1999 August 11, a total eclipse of the Sun will be visible from within a narrow corridor which traverses the Eastern Hemisphere. The path of the Moon's umbral shadow begins in the Atlantic and crosses central Europe, the Middle East, and India, where it ends at sunset in the Bay of Bengal. A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes northeastern North America, all of Europe, northern Africa, and the western half of Asia. Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for approximately 1400 cities, maps of the eclipse path, weather prospects, the lunar limb profile, and the sky during totality. Tips and suggestions are also given on how to safely view and photograph the eclipse.
Musick, Charles R [Castro Valley, CA; Critchlow, Terence [Livermore, CA; Ganesh, Madhaven [San Jose, CA; Slezak, Tom [Livermore, CA; Fidelis, Krzysztof [Brentwood, CA
2006-12-19
A system and method is disclosed for integrating and accessing multiple data sources within a data warehouse architecture. The metadata formed by the present method provide a way to declaratively present domain specific knowledge, obtained by analyzing data sources, in a consistent and useable way. Four types of information are represented by the metadata: abstract concepts, databases, transformations and mappings. A mediator generator automatically generates data management computer code based on the metadata. The resulting code defines a translation library and a mediator class. The translation library provides a data representation for domain specific knowledge represented in a data warehouse, including "get" and "set" methods for attributes that call transformation methods and derive a value of an attribute if it is missing. The mediator class defines methods that take "distinguished" high-level objects as input and traverse their data structures and enter information into the data warehouse.
MR imaging of apparent 3He gas transport in narrow pipes and rodent airways
NASA Astrophysics Data System (ADS)
Minard, Kevin R.; Jacob, Richard E.; Laicher, Gernot; Einstein, Daniel R.; Kuprat, Andrew P.; Corley, Richard A.
2008-10-01
High sensitivity makes hyperpolarized 3He an attractive signal source for visualizing gas flow with magnetic resonance (MR) imaging. Its rapid Brownian motion, however, can blur observed flow lamina and alter measured diffusion rates when excited nuclei traverse shear-induced velocity gradients during data acquisition. Here, both effects are described analytically, and predicted values for measured transport during laminar flow through a straight, 3.2-mm diameter pipe are validated using two-dimensional (2D) constant-time images of different binary gas mixtures. Results show explicitly how measured transport in narrow conduits is characterized by apparent values that depend on underlying gas dynamics and imaging time. In ventilated rats, this is found to obscure acquired airflow images. Nevertheless, flow splitting at airway branches is still evident and use of 3D vector flow mapping is shown to reveal surprising detail that highlights the correlation between gas dynamics and lung structure.
High latitude currents in the 0600 to 0900 MLT sector - Observations from Viking and DMSP-F7
NASA Technical Reports Server (NTRS)
Bythrow, P. F.; Potemra, T. A.; Zanetti, L. J.; Erlandson, R. A.; Hardy, D. A.; Rich, F. J.; Acuna, M. H.
1987-01-01
High-resolution magnetic field and charged-particle data acquired on March 25, 1986 by the Viking and DMSP-F7 satellites, as they traversed the dawn sector auroral zone on nearly antiparallel trajectories within 40 min of each oher, are analyzed. Magnetic field measurements by Viking at 0850 MLT and by DMSP at 0630 MLT indicate the presence of a large-scale earthward-directed region 1 Birkeland current and an upward-flowing region 2 current. Both satellites also observed a third Birkeland current adjacent to and poleward of the region 1 system with opposite flow. This poleward system is about 0.5 deg invariant latitude wide and has a current density comparable to the region 1 and 2 systems. The highest-latitude current is identified as region 0. Its charged-particle signatures were used to infer field line mapping to the equatorial plane.
Spirit's Travels During its First 238 Martian Days
NASA Technical Reports Server (NTRS)
2004-01-01
This map shows the complete traverse of NASA's Mars Exploration Rover Spirit through the rover's 238th martian day, or sol (Sept. 3, 2004). This was shortly before the rover stopped driving for about two weeks while Mars was nearly behind the Sun from Earth's perspective. The background image consists of frames from the Mars Orbiter Camera on NASA's Mars Global Surveyor orbiter. Inset images along the route are from Spirit's navigation camera. From its landing site, Spirit drove up to the rim of 'Bonneville' crater on the far left and to the north rim of 'Missoula' crater. Then it commenced a long drive across the plains, deviating to avoid large hollows. Upon arrival at the base of the 'Columbia Hills,' Spirit drove north for a short distance before beginning its ascent onto the 'West Spur,' where it is currently located. The scale bar at lower left is 500 meters (1,640 feet). North is up.Cheap or Robust? The practical realization of self-driving wheelchair technology.
Burhanpurkar, Maya; Labbe, Mathieu; Guan, Charlie; Michaud, Francois; Kelly, Jonathan
2017-07-01
To date, self-driving experimental wheelchair technologies have been either inexpensive or robust, but not both. Yet, in order to achieve real-world acceptance, both qualities are fundamentally essential. We present a unique approach to achieve inexpensive and robust autonomous and semi-autonomous assistive navigation for existing fielded wheelchairs, of which there are approximately 5 million units in Canada and United States alone. Our prototype wheelchair platform is capable of localization and mapping, as well as robust obstacle avoidance, using only a commodity RGB-D sensor and wheel odometry. As a specific example of the navigation capabilities, we focus on the single most common navigation problem: the traversal of narrow doorways in arbitrary environments. The software we have developed is generalizable to corridor following, desk docking, and other navigation tasks that are either extremely difficult or impossible for people with upper-body mobility impairments.
NASA Technical Reports Server (NTRS)
Schwartzberg, F. R.; Toth, C., Jr.; King, R. G.; Todd, P. H., Jr.
1979-01-01
The technique for inspection of railroad rails containing transverse fissure defects was discussed. Both pulse-echo and pitch-catch inspection techniques were used. The pulse-echo technique results suggest that a multiple-scan approach using varying angles of inclination, three-surface scanning, and dual-direction traversing may offer promise of characterization of transverse defects. Because each scan is likely to produce a reflection indicating only a portion of the defect, summing of the individual reflections must be used to obtain a reasonably complete characterization of the defect. The ability of the collimated pitch-catch technique to detect relatively small amounts of flaw growth was shown. The method has a problem in characterizing the portions of the defect near the top surface or web intersection. The work performed was a preliminary evaluation of the prospects for automated mapping of rail flaws.
On load paths and load bearing topology from finite element analysis
NASA Astrophysics Data System (ADS)
Kelly, D.; Reidsema, C.; Lee, M.
2010-06-01
Load paths can be mapped from vector plots of 'pointing stress vectors'. They define a path along which a component of load remains constant as it traverses the solution domain. In this paper the theory for the paths is first defined. Properties of the plots that enable a designer to interpret the structural behavior from the contours are then identified. Because stress is a second order tensor defined on an orthogonal set of axes, the vector plots define separate paths for load transfer in each direction of the set of axes. An algorithm is therefore presented that combines the vectors to define a topology to carry the loads. The algorithm is shown to straighten the paths reducing bending moments and removing stress concentration. Application to a bolted joint, a racing car body and a yacht hull demonstrate the usefulness of the plots.
Quantum control via a genetic algorithm of the field ionization pathway of a Rydberg electron
NASA Astrophysics Data System (ADS)
Gregoric, Vincent C.; Kang, Xinyue; Liu, Zhimin Cheryl; Rowley, Zoe A.; Carroll, Thomas J.; Noel, Michael W.
2017-08-01
Quantum control of the pathway along which a Rydberg electron field ionizes is experimentally and computationally demonstrated. Selective field ionization is typically done with a slowly rising electric field pulse. The (1/n*)4 scaling of the classical ionization threshold leads to a rough mapping between arrival time of the electron signal and principal quantum number of the Rydberg electron. This is complicated by the many avoided level crossings that the electron must traverse on the way to ionization, which in general leads to broadening of the time-resolved field ionization signal. In order to control the ionization pathway, thus directing the signal to the desired arrival time, a perturbing electric field produced by an arbitrary wave-form generator is added to a slowly rising electric field. A genetic algorithm evolves the perturbing field in an effort to achieve the target time-resolved field ionization signal.
On the Moon with Apollo 15, A Guidebook to Hadley Rille and the Apennine Mountains.
ERIC Educational Resources Information Center
Simmons, Gene
The booklet, published before the Apollo 15 mission, gives a timeline for the mission; describes and illustrates the physiography of the landing site; and describes and illustrates each lunar surface scientific experiment. Separate timelines are included for all traverses (the traverses are the Moon walks and, for Apollo 15, the Moon rides in the…
Astronauts Young and Duke collect rock samples along simulated lunar traverse
NASA Technical Reports Server (NTRS)
1971-01-01
Astronauts John W. Young, left, prime crew commander for Apollo 16, and Charles M. Duke Jr., lunar module pilot, collect rock samples along a simulated lunar traverse route in the Coso Hills, near Ridgecrest, California. Astronaut Eugene A. Cernan, right background, prime crew commander for Apollo 17, looks on. The astronauts trained at the U.S. Naval Ordnance Test Station.
Low-Speed Wind Tunnel Flow Quality Determination
2011-09-01
Traverse Motor The traverse motor for the BiSlide is a NEMA Type 34D, Slo-Syn® stepper motor, allowing the operator to position items in the test... norm (w1)^2/sum(w1)^2,’k’); %% plot on log-log scale ylabel(‘RMS Power/Frequency (V^2)’) xlabel(‘Frequency (Hz)’) title(‘Power Spectrum’) end
An Experimental Investigation of an Airfoil Traversing Across a Shear Flow
NASA Astrophysics Data System (ADS)
Hamedani, Borhan A.; Naguib, Ahmed; Koochesfahani, Manoochehr
2017-11-01
While the aerodynamics of an airfoil in a uniform approach flow is well understood, less attention has been paid to airfoils in non-uniform flows. An aircraft encounters such flow, for example, during landing through the air wake of an aircraft carrier. The present work is focused on investigating the fundamental aerodynamics of airfoils in such an environment using canonical flow experiments. To generate a shear approach flow, a shaped honeycomb block is employed in a wind tunnel setup. Direct force measurements are performed on a NACA 0012 airfoil, with an aspect ratio of 1.8, as the airfoil traverses steadily across the shear region. Measurements are conducted at a chord Reynolds number Rec 75k, based on the mean approach stream velocity at the center of the shear zone, for a range of airfoil traverse velocities and angles of attack (0 - 12 degree). The results are compared to those obtained for the same airfoil when placed statically at different points along the traverse path inside the shear zone. The comparison enables examination of the applicability of quasi-steady analysis in computing the forces on the moving airfoil. This work is supported by ONR Grant Number N00014-16-1-2760.
NASA Astrophysics Data System (ADS)
Moghadam, Danial Ghahremani; Farhangdoost, Khalil; Nejad, Reza Masoudi
2016-06-01
Friction stir welding was conducted on 8-mm-thick plates made of AA2024-T351 aluminum alloy at tool traverse speeds between 8 and 31.5 mm/minutes and tool rotational speed between 400 and 800 rpm. Metallographic analyses and mechanical tests including hardness, tensile, residual stress, and fracture toughness tests were carried out to evaluate the microstructural and mechanical properties of the joints as a function of the process parameters. The finite element simulation of the FSW process was also performed using a thermal model. The hardness test results show that the increase in rotational speed or decrease in traverse speed of the tool would cause a decrease in weld zone hardness. The best tensile properties are obtained at rotational/traverse speed ratio between 20 and 32. Also, the longitudinal residual stress profiles were evaluated by employing X-ray diffraction method. The numerical and experimental results showed that the increase in a traverse or rotational speed would increase the residual stress of the weld zone. From the fracture toughness results, it was found that the welding process decreases the joints fracture toughness 18 to 49 pct with respect to the base metal.
Nowlan, G.A.; Gerstel, W.J.
1985-01-01
The study area is bounded by several areas of known mineralization (Hedl und and others, 1983). Vein and bedding replacement deposits of silver, zinc, and lead were mined from 1890 until about 1918 in the vicinity of Weston Pass (map A), on the northeastern border of the study area. Gold and silver were mined from about 1860 until about 1880 from veins in the Granite area (map A), on the northwestern border of the study area; minor prospecting activity continues today. From 1935 to 1937, veins of gold, silver, and base metals were mined in the vicinity of Fourmile Creek, on the southwestern border of the study area (map A). Recently, active uranium prospecting has been taking place in the vicinity of the Middle Fork of Salt Creek, on the southeastern border of the study area (map A).
A new computer approach to mixed feature classification for forestry application
NASA Technical Reports Server (NTRS)
Kan, E. P.
1976-01-01
A computer approach for mapping mixed forest features (i.e., types, classes) from computer classification maps is discussed. Mixed features such as mixed softwood/hardwood stands are treated as admixtures of softwood and hardwood areas. Large-area mixed features are identified and small-area features neglected when the nominal size of a mixed feature can be specified. The computer program merges small isolated areas into surrounding areas by the iterative manipulation of the postprocessing algorithm that eliminates small connected sets. For a forestry application, computer-classified LANDSAT multispectral scanner data of the Sam Houston National Forest were used to demonstrate the proposed approach. The technique was successful in cleaning the salt-and-pepper appearance of multiclass classification maps and in mapping admixtures of softwood areas and hardwood areas. However, the computer-mapped mixed areas matched very poorly with the ground truth because of inadequate resolution and inappropriate definition of mixed features.
NASA Technical Reports Server (NTRS)
Quiroga, S. Q.
1977-01-01
The applicability of LANDSAT digital information to soil mapping is described. A compilation of all cartographic information and bibliography of the study area is made. LANDSAT MSS images on a scale of 1:250,000 are interpreted and a physiographic map with legend is prepared. The study area is inspected and a selection of the sample areas is made. A digital map of the different soil units is produced and the computer mapping units are checked against the soil units encountered in the field. The soil boundaries obtained by automatic mapping were not substantially changed by field work. The accuracy of the automatic mapping is rather high.
Only Above Barrier Energy Components Contribute to Barrier Traversal Time
NASA Astrophysics Data System (ADS)
Galapon, Eric A.
2012-04-01
A time of arrival operator across a square potential barrier is constructed. The expectation value of the barrier time of arrival operator for a sufficiently localized incident wave packet is compared with the expectation value of the free particle time of arrival operator for the same wave packet. The comparison yields an expression for the expected traversal time across the barrier. It is shown that only the above barrier components of the momentum distribution of the incident wave packet contribute to the barrier traversal time, implying that below the barrier components are transmitted without delay. This is consistent with the recent experiment in attosecond ionization in helium indicating that there is no real tunneling delay time [P. Eckle , Science 322, 1525 (2008)SCIEAS0036-807510.1126/science.1163439].
Al-Mg Isotope Study of Allende 5241
NASA Technical Reports Server (NTRS)
Kerekgyarto, A. G.; Jeffcoat, C. R.; Lapen, T. J.; Andreasen, R.; Righter, M.; Ross, D. K.; Simon, J. I.
2016-01-01
The defining characteristic of type B1 CAIs is a large (.5- 3mm) concentric melilite mantle [1]. In [2] we presented two isochrons from separate traverses across the melilite mantle of Allende EK 459-5-1. The primary petrographic differences between the traverses was the preservation of strong oscillatory zoning. The traverse that crossed the distinctive oscillatory zone produced a pristine internal isochron, while the other that did not have a strongly preserved oscillatory zone produced a disturbed isochron indicated by more scatter (higher MSWD) and a positive (delta)26Mg* intercept. The implication simply being that the oscillatory zone may represent varying conditions during the mantle formation event. We targeted a similar texture in Allende 5241 using the same methodology in an attempt to achieve similar results.
On Fusing Recursive Traversals of K-d Trees
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rajbhandari, Samyam; Kim, Jinsung; Krishnamoorthy, Sriram
Loop fusion is a key program transformation for data locality optimization that is implemented in production compilers. But optimizing compilers currently cannot exploit fusion opportunities across a set of recursive tree traversal computations with producer-consumer relationships. In this paper, we develop a compile-time approach to dependence characterization and program transformation to enable fusion across recursively specified traversals over k-ary trees. We present the FuseT source-to-source code transformation framework to automatically generate fused composite recursive operators from an input program containing a sequence of primitive recursive operators. We use our framework to implement fused operators for MADNESS, Multiresolution Adaptive Numerical Environmentmore » for Scientific Simulation. We show that locality optimization through fusion can offer more than an order of magnitude performance improvement.« less
Remote battlefield observer technology (REBOT)
NASA Astrophysics Data System (ADS)
Lanzagorta, Marco O.; Uhlmann, Jeffrey K.; Julier, Simon J.; Kuo, Eddy
1999-07-01
Battlefield situation awareness is the most fundamental prerequisite for effective command and control. Information about the state of the battlefield must be both timely and accurate. Imagery data is of particular importance because it can be directly used to monitor the deployment of enemy forces in a given area of interest, the traversability of the terrain in that area, as well as many other variables that are critical for tactical and force level planning. In this paper we describe prototype REmote Battlefield Observer Technology (REBOT) that can be deployed at specified locations and subsequently tasked to transmit high resolution panoramic imagery of its surrounding area. Although first generation REBOTs will be stationary platforms, the next generation will be autonomous ground vehicles capable of transporting themselves to specified locations. We argue that REBOT fills a critical gap in present situation awareness technologies. We expect to provide results of REBOT tests to be conducted at the 1999 Marines Advanced Warfighting Demonstration.
A Stab in the Dark?: A Research Note on Temporal Patterns of Street Robbery.
Tompson, Lisa; Bowers, Kate
2013-11-01
Test the influence of darkness in the street robbery crime event alongside temperature. Negative binomial regression models tested darkness and temperature as predictors of street robbery. Units of analysis were four 6-hr time intervals in two U.K. study areas that have different levels of darkness and variations of temperature throughout the year. Darkness is a key factor related to robbery events in both study areas. Traversing from full daylight to full darkness increased the predicted volume of robbery by a multiple of 2.6 in London and 1.2 in Glasgow. Temperature was significant only in the London study area. Interaction terms did not enhance the predictive power of the models. Darkness is an important driving factor in seasonal variation of street robbery. A further implication of the research is that time of the day patterns are crucial to understanding seasonal trends in crime data.
Geology of a Portion of the Martian Highlands: MTMs -20002, -20007, -25002 and -25007
NASA Technical Reports Server (NTRS)
Fortezzo, C. M.; Williams, K. K.
2009-01-01
As part of a continuing study to understand the relationship between valleys and highland resurfacing through geologic mapping, we are continuing to map seven MTM quads in portions of the Margaritifer, Arabia, and Noachis Terrae. Results from this mapping will also help constrain the role and extent of past water in the region. The MTMs are grouped in two different areas: a 4-quadrangle area (-20002, -20007, -25002, -25007) and an L-shaped area (-15017, -20017, -20022) within the region [1-5]. This abstract focuses on the geologic units and history from mapping in the 4-quadrangle area, but includes a brief update on the L-shaped map area.
St. Louis Area Earthquake Hazards Mapping Project
Williams, Robert A.; Steckel, Phyllis; Schweig, Eugene
2007-01-01
St. Louis has experienced minor earthquake damage at least 12 times in the past 200 years. Because of this history and its proximity to known active earthquake zones, the St. Louis Area Earthquake Hazards Mapping Project will produce digital maps that show variability of earthquake hazards in the St. Louis area. The maps will be available free via the internet. They can be customized by the user to show specific areas of interest, such as neighborhoods or transportation routes.
Spatial Analysis of Land Adjustment as a Rehabilitation Base of Mangrove in Indramayu Regency
NASA Astrophysics Data System (ADS)
Sodikin; Sitorus, S. R. P.; Prasetyo, L. B.; Kusmana, C.
2018-02-01
Indramayu Regency is the area that has the largest mangrove in West Java. According to the environment and forestry ministry of Indramayu district will be targeted to be the central area of mangrove Indonesia. Mangroves in the regency from the 1990s have experienced a significant decline caused by the conversion of mangrove land into ponds and settlements. To stop the mangrove decline that continues to occur, it is necessary to rehabilitate mangroves in the area. The rehabilitation of mangrove should be in the area suitable for mangrove growth and what kind of vegetation analysis is appropriate to plant the area, so the purpose of this research is to analyze the suitability of land for mangrove in Indramayu Regency. This research uses geographic information system with overlay technique, while the data used in this research is tidal map of sea water, salintas map, land ph map, soil texture map, sea level rise map, land use map, community participation level map, and Map of organic soil. Then overlay and adjusted to matrix environmental parameters for mangrove growth. Based on the results of the analysis is known that in Indramayu District there are 5 types of mangroves that fit among others Bruguera, Soneratia, Nypah, Rhizophora, and Avicennia. The area of each area is Bruguera with an area of 6260 ha, 2958 ha, nypah 1756 ha, Rhizophora 936, and Avicennia 433 ha.