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1

SRTM Anaglyph with Landsat Overlay: Los Angeles to San Joaquin Valley, California  

NASA Technical Reports Server (NTRS)

California's topography poses challenges for road builders. Northwest of Los Angeles, deformation of Earth's crust along the Pacific-North American crustal plate boundary has made transportation difficult. Direct connection between metropolitan Los Angeles (image lower left) and California's Central Valley (image top center) through the rugged terrain seen on the left side of this image was long avoided in favor of longer but easier paths. However, over the last century, three generations of roads have traversed this terrain. The first was 'The Ridge Route', a two-lane road, built in 1915, which followed long winding ridge lines that included 697curves. The second, built in 1933, was to become four-lane U.S. Highway 99. It generally followed widened canyon bottoms. The third is the current eight lane Interstate 5 freeway, built in the 1960s, which is generally notched into hillsides, but also includes a stretch of several miles where the two directions of travel are widely separated and driving is 'on the left', a rarity in the United States. Such an unusual highway configuration was necessary in order to optimize the road grades for uphill and downhill traffic in this topographically challenging setting.

This anaglyph was generated by first draping a Landsat satellite image over a preliminary topographic map from the Shuttle Radar Topography Mission, then generating two differing perspectives, one for each eye. When viewed through special glasses, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter. Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30 meter resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive.

The elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

Size: 141 by 107 kilometers (88 by 66 miles) Location: 34.5 deg. North lat., 118.7 deg. West lon. Orientation: North toward upper right Image: Landsat bands 1,2,3 averaged (visible light as grey) Date Acquired: February 16, 2000 (SRTM), November 11, 1986 (Landsat) Image: NASA/JPL/NIMA

2000-01-01

2

SRTM Stereo Pair with Landsat Overlay: Los Angeles to San Joaquin Valley, California  

NASA Technical Reports Server (NTRS)

California's topography poses challenges for road builders. Northwest of Los Angeles, deformation of Earth's crust along the Pacific-North American crustal plate boundary has made transportation difficult. Direct connection between metropolitan Los Angeles (image lower left) and California's Central Valley (image top center) through the rugged terrain seen on the left side of this image was long avoided in favor of longer, but easier paths. However, over the last century, three generations of roads have traversed this terrain. The first was 'The Ridge Route', a two-lane road, built in 1915, which followed long winding ridge lines that included 697curves. The second, built in 1933, was to become four-lane U.S. Highway 99. It generally followed widened canyon bottoms. The third is the current eight lane Interstate 5 freeway, built in the 1960s, which is generally notched into hillsides, but also includes a stretch of several miles where the two directions of travel are widely separated and driving is 'on the left', a rarity in the United States. Such an unusual highway configuration was necessary in order to optimize the road grades for uphill and downhill traffic in this topographically challenging setting.

This stereoscopic image was generated by draping a Landsat satellite image over a preliminary SRTM elevation model. Two differing perspectives were then calculated, one for each eye. They can be seen in 3-D by viewing the left image with the right eye and the right image with the left eye (cross-eyed viewing), or by downloading and printing the image pair, and viewing them with a stereoscope. When stereoscopically merged, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions. Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30 meter resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive.

The elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

Size: 141 by 107 kilometers (88 by 66 miles) Location: 34.5 deg. North lat., 118.7 deg. West lon. Orientation: North toward upper right Image: Landsat bands 1, 2&4, 3 as blue, green, and red, respectively Date Acquired: February 16, 2000 (SRTM), November 11, 1986 (Landsat) Image: NASA/JPL/NIMA

2000-01-01

3

Perspective view, Landsat overlay Pasadena, California  

NASA Technical Reports Server (NTRS)

This image shows a perspective view of the area around Pasadena, California, just north of Los Angeles. The cluster of hills surrounded by freeways on the left is the Verdugo Hills, which lie between the San Gabriel Valley in the foreground and the San Fernando Valley in the upper left. The San Gabriel Mountains are seen across the top of the image, and parts of the high desert near the city of Palmdale are visible along the horizon on the right. Several urban features can be seen in the image. NASA's Jet Propulsion Laboratory (JPL) is the bright cluster of buildings just right of center; the flat tan area to the right of JPL at the foot of the mountains is a new housing development devoid of vegetation. Two freeways (the 210 and the 134) cross near the southeastern end of the Verdugo Hills near a white circular feature, the Rose Bowl. The commercial and residential areas of the city of Pasadena are the bright areas clustered around the freeway. These data will be used for a variety of applications including urban planning and natural hazard risk analysis.

This type of display adds the important dimension of elevation to the study of land use and environmental processes as observed in satellite images. The perspective view was created by draping a Landsat satellite image over an SRTM elevation model. Topography is exaggerated 1.5 times vertically. The Landsat image was provided by the United States Geological Survey's Earth Resources Observations Systems (EROS) Data Center, Sioux Falls, South Dakota.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise,Washington, DC.

Size: Varies in a perspective view Location: 34.18 deg. North lat., 118.16 deg. West lon. Orientation: Looking Northwest Original Data Resolution: SRTM and Landsat: 30 meters (99 feet) Date Acquired: February 16, 2000

2000-01-01

4

Perspective View with Landsat Overlay, Costa Rica  

NASA Technical Reports Server (NTRS)

This perspective view shows the Caribbean coastal plain of Costa Rica, with the Cordillera Central rising in the background and the Pacific Ocean in the distance. The prominent river in the center of the image is the Rio Sucio, which merges with the Rio Sarapiqui at the bottom of the image and eventually joins with Rio San Juan on the Nicaragua border.

Like much of Central America, Costa Rica is generally cloud covered so very little satellite imagery is available. The ability of the Shuttle Radar Topography Mission (SRTM) instrument to penetrate clouds and make three-dimensional measurements will allow generation of the first complete high-resolution topographic map of the entire region. These data were used to generate the image.

This three-dimensional perspective view was generated using elevation data from SRTM and an enhanced false-color Landsat 7 satellite image. Colors are from Landsat bands 5, 4, and 2 as red, green and blue, respectively. Topographic expression is exaggerated two times.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center, Sioux Falls, S.D.

Elevation data used in this image was acquired by the SRTM aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C.

Size: scale varies in this perspective image Location: 10.4 degrees North latitude, 84.0 degrees West longitude Orientation: looking Southwest Image Data: Landsat Bands 5, 4, 3 as red, green, blue respectively Original Data Resolution: SRTM 30 meters (99 feet) Date Acquired: February 2000 (SRTM)

2002-01-01

5

Perspective view, Landsat overlay Oahu, Hawaii  

NASA Technical Reports Server (NTRS)

Honolulu, on the island of Oahu, is a large and growing urban area with limited space and water resources. This perspective view, combining a Landsat image with SRTM topography, shows how the topography controls the urban growth pattern, causes cloud formation, and directs the rainfall runoff pattern. Features of interest in this scene include downtown Honolulu (right), Honolulu Harbor (right), Pearl Harbor (center), and offshore reef patterns (foreground). The Koolau mountain range runs through the center of the image. On the north shore of the island are the Mokapu Peninsula and Kaneohe Bay (upper right). Clouds commonly hang above ridges and peaks of the Hawaiian Islands, and in this rendition appear draped directly on the mountains. The clouds are actually about 1000 meters (3300 feet) above sea level. High resolution topographic and image data allow ecologists and planners to assess the effects of urban development on the sensitive ecosystems in tropical regions.

This type of display adds the important dimension of elevation to the study of land use and environmental processes as observed in satellite images. The perspective view was created by draping a Landsat 7 satellite image over an SRTM elevation model. Topography is exaggerated about six times vertically. The Landsat 7 image was acquired on February 12, 2000, and was provided by the United States Geological Survey's Earth Resources Observations Systems (EROS)Data Center, Sioux Falls, South Dakota.

The Shuttle Radar Topography Mission (SRTM), launched on February 11, 2000, uses the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging antenna and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) and the German (DLR) and Italian (ASI) space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

Size: 28 by 56 kilometers (17 by 35 miles) Location: 21.4 deg. North lat., 157.8 deg. West lon. Orientation: Looking North Original Data Resolution: SRTM, 30 meters (99 feet); Landsat, 15 meters (50 feet) Date Acquired: SRTM, February 18, 2000; Landsat February 12, 2000 Image: NASA/JPL/NIMA

2000-01-01

6

Perspective View with Landsat Overlay, Sacramento, Calif.  

NASA Technical Reports Server (NTRS)

California's state capitol, Sacramento, can be seen clustered along the American and Sacramento Rivers in this computer-generated perspective viewed from the west. Folsom Lake is in the center and the Sierra Nevada is above, with the edge of Lake Tahoe just visible at top center.

This 3-D perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and an enhanced color Landsat 5satellite image. Topographic expression is exaggerated two times.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR)that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C.

Size: scale varies in this perspective image Location: 38.6 deg. North lat., 121.3 deg. West lon. Orientation: looking east Image Data: Landsat Bands 3, 2, 1 as red, green, blue, respectively Original Data Resolution: SRTM 1 arcsecond (30 meters or 98 feet), Thematic Mapper 1 arcsecond (30 meters or 98 feet) Date Acquired: February 2000 (SRTM)

2002-01-01

7

Malaspina Glacier, Alaska, Perspective with Landsat Overlay  

NASA Technical Reports Server (NTRS)

Malaspina Glacier in southeastern Alaska is considered the classic example of a piedmont glacier. Piedmont glaciers occur where valley glaciers exit a mountain range onto broad lowlands, are no longer laterally confined, and spread to become wide lobes. Malaspina Glacier is actually a compound glacier, formed by the merger of several valley glaciers, the most prominent of which seen here are Agassiz Glacier (left) and Seward Glacier (right). In total, Malaspina Glacier is up to 65 kilometers (40 miles) wide and extends up to 45 kilometers (28 miles) from the mountain front nearly to the sea.

This perspective view was created from a Landsat satellite image and an elevation model generated by the Shuttle Radar Topography Mission (SRTM). Landsat views both visible and infrared light, which have been combined here into a color composite that generally shows glacial ice in light blue, snow in white, vegetation in green, bare rock in grays and tans, and the ocean (foreground) in dark blue. The back (northern) edge of the data set forms a false horizon that meets a false sky.

Glaciers erode rocks, carry them down slope, and deposit them at the edge of the melting ice, typically in elongated piles called moraines. The moraine patterns at Malaspina Glacier are quite spectacular in that they have huge contortions that result from the glacier crinkling as it gets pushed from behind by the faster-moving valley glaciers.

Glaciers are sensitive indicators of climatic change. They can grow and thicken with increasing snowfall and/or decreased melting. Conversely, they can retreat and thin if snowfall decreases and/or atmospheric temperatures rise and cause increased melting. Landsat imaging has been an excellent tool for mapping the changing geographic extent of glaciers since 1972. The elevation measurements taken by SRTM in February 2000 now provide a near-global baseline against which future non-polar region glacial thinning or thickening can be assessed.

Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency of the U.S. Department of Defense, and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC. Size: 55 kilometers wide x 55 kilometers distance (34 x 34 miles) Location: 60 deg N latitude, 140 deg W longitude Orientation: View North, 2X vertical exaggeration Image Data: Landsat Thematic Mapper false-color image Original Data Resolution: SRTM 1 arcsecond (30 meters or 98 feet), Landsat 30 meters (98 feet) Date Acquired: February 2000 (SRTM), 31 August 2000 (Landsat)

2003-01-01

8

SRTM Perspective View with Landsat Overlay: Mt. Pinos, California  

NASA Technical Reports Server (NTRS)

Prominently displayed in this image, Mt. Pinos, at 2,692 meters (8,831 feet) is the highest peak in the Los Padres National Forest. Named for the mantle of pine trees covering its slopes and summit, it offers one of the best stargazing sites in Southern California. Shuttle Radar Topography Mission (SRTM) elevation data were combined with Landsat data to generate this perspective view looking toward the northwest. Not only is the mountain popular with astronomers and astro-photographers, it is also popular for hiking trails and winter sports.

The broad low relief area in the right foreground is Cuddy Valley. Cuddy Valley Road is the bright line on the right (north)side of the valley. Just to the left and paralleling the road is a scarp (cliff) formed by the San Andreas fault. The fault slices through the mountains here and then bends and continues onto the Carrizo Plain (right center horizon). This entire segment of the San Andreas fault broke in a major earthquake in 1857.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data match the 30-meter(98-foot) resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive. For visualization purposes, topographic heights displayed in this image are exaggerated two times. Colors approximate natural colors.

The elevation data used in this image was acquired by SRTM aboard Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of Earth's land surface. To collect the 3-D SRTM data, engineers added a mast 60 meters (about 200 feet)long, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense, and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C. JPL is a division of the California Institute of Technology in Pasadena.

Distance to Horizon: 176 kilometers (109 miles) Location: 34.8 deg. North lat., 119.1 deg. West lon. View: Toward the Northwest Date Acquired: February 16, 2000 SRTM, December 14, 1984 Landsat

2001-01-01

9

Perspective View, SRTM / Landsat, Los Angeles, Calif  

NASA Technical Reports Server (NTRS)

Los Angeles, Calif., is one of the world's largest metropolitan areas with a population of about 15 million people. The urban areas mostly cover the coastal plains and lie within the inland valleys. The intervening and adjacent mountains are generally too rugged for much urban development. This in large part because the mountains are 'young', meaning they are still building (and eroding) in this seismically active (earthquake prone) region.

Earthquake faults commonly lie between the mountains and the lowlands. The San Andreas fault, the largest fault in California, likewise divides the very rugged San Gabriel Mountains from the low-relief Mojave Desert, thus forming a straight topographic boundary between the top center and lower right corner of the image. We present two versions of this perspective image from NASA's Shuttle Radar Topography Mission (SRTM): one with and one without a graphic overlay that maps faults that have been active in Late Quaternary times (white lines). The fault database was provided by the U.S. Geological Survey.

For the annotated version of this image, please select Figure 1, below: [figure removed for brevity, see original site] (Large image: 2 mB jpeg)

The Landsat image used here was acquired on May 4, 2001, about seven weeks before the summer solstice, so natural terrain shading is not particularly strong. It is also not especially apparent given a view direction (northwest) nearly parallel to the sun illumination (shadows generally fall on the backsides of mountains). Consequently, topographic shading derived from the SRTM elevation model was added to the Landsat image, with a false sun illumination from the left (southwest). This synthetic shading enhances the appearance of the topography.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and substantially helps in analyzing the large and growing Landsat image archive. This Landsat 7 Thematic Mapper image was provided to the SRTM project by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center, Sioux Falls, S.D.

Elevation data used in this image was acquired by the SRTM aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C.

Size: View width 134 kilometers (83 miles); view distance 150 kilometers (93 miles) Location: 34.3 degrees North latitude, 118.4 degrees West longitude Orientation: View west-northwest, 1.8 X vertical exaggeration Image Data: Landsat Bands 3, 2+4, 1 as red, green, blue, respectively Original Data Resolution: SRTM 1 arcsecond (30 meters or 98 feet), Landsat 30 meters (98 feet) Graphic Data: earthquake faults active in Late Quaternary times Date Acquired: February 2000 (SRTM), May 4, 2001 (Landsat).

2002-01-01

10

Perspective view, Landsat overlay San Andreas Fault, Palmdale, California  

NASA Technical Reports Server (NTRS)

The prominent linear feature straight down the center of this perspective view is the San Andreas Fault. This segment of the fault lies near the city of Palmdale, California (the flat area in the right half of the image) about 60 kilometers (37 miles) north of Los Angeles. The fault is the active tectonic boundary between the North American plate on the right, and the Pacific plate on the left. Relative to each other, the Pacific plate is moving away from the viewer and the North American plate is moving toward the viewer along what geologists call a right lateral strike-slip fault. Two large mountain ranges are visible, the San Gabriel Mountains on the left and the Tehachapi Mountains in the upper right. The Lake Palmdale Reservoir, approximately 1.5 kilometers (0.9 miles) across, sits in the topographic depression created by past movement along the fault. Highway 14 is the prominent linear feature starting at the lower left edge of the image and continuing along the far side of the reservoir. The patterns of residential and agricultural development around Palmdale are seen in the Landsat imagery in the right half of the image. SRTM topographic data will be used by geologists studying fault dynamics and landforms resulting from active tectonics.

This type of display adds the important dimension of elevation to the study of land use and environmental processes as observed in satellite images. The perspective view was created by draping a Landsat satellite image over an SRTM elevation model. Topography is exaggerated 1.5 times vertically. The Landsat image was provided by the United States Geological Survey's Earth Resources Observations Systems (EROS) Data Center, Sioux Falls, South Dakota.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise,Washington, DC.

Size: Varies in a perspective view Location: 34.58 deg. North lat., 118.13 deg. West lon. Orientation: Looking Northwest Original Data Resolution: SRTM and Landsat: 30 meters (99 feet) Date Acquired: February 16, 2000

2000-01-01

11

Perspective View with Landsat Overlay, Mount Shasta, Calif.  

NASA Technical Reports Server (NTRS)

The volcanic nature of Mount Shasta is clearly evident in this computer-generated perspective viewed from the northwest. At over 4,300 meters (14,000 feet), Mount Shasta is California's tallest volcano and part of the Cascade chain of volcanoes extending south from Washington. The twin summits of Shasta and Shastina tower over a lava flow on the flank of the volcano. Cutting across the lava flow is the bright line of a railroad. The bright area at the right edge is the town of Weed.

This 3-D perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and an enhanced false-color Landsat 5 satellite image. Colors are from Landsat bands 3, 2, and 1 as red, green and blue, respectively. Topographic expression is exaggerated two times.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive.

The Landsat Thematic Mapper image used here came from an online mosaic of Landsat images for the continental United States (http://mapus.jpl.nasa.gov), a part of NASA's Digital Earth effort.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C.

Size: scale varies in this perspective image Location: 41.4 degrees North latitude, 122.3 degrees West longitude Orientation: looking southeast Image Data: Landsat Bands 3, 2, 1 as red, green, blue, respectively Original Data Resolution: SRTM 1 arcsecond (30 meters or 98 feet) Thematic Mapper 1 arcsecond (30 meters or 98 feet) Date Acquired: February 2000 (SRTM)

2002-01-01

12

SRTM Perspective View with Landsat Overlay: Bhuj, India  

NASA Technical Reports Server (NTRS)

This perspective view shows the city of Bhuj, India, in the foreground (gray area). Bhuj and many other nearby towns and cities were almost completely destroyed by the shaking of an earthquake in western India on January 26, 2001. This magnitude 7.6 earthquake was the deadliest in the history of India with some 20,000 fatalities and over a million homes damaged or destroyed. The epicenter of the earthquake was in the area in the background of this view.

Bhuj was the historical capital of the Kachchh region, and the Bhuj airport is the prominent dark line with light borders to the left of the center of the image. Highways and rivers appear as dark lines. Vegetation appears bright green in this false-color Landsat image. The Gulf of Kachchh (or Kutch) is the dark blue area in the upper right corner of the image. The hills reach up to 500 meters (1,500 feet) elevation. The light blue area in the background center of the image is low-lying salt flats called the Rann of Kachchh.

This three-dimensional perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM). This image was generated using topographic data from SRTM and an enhanced false-color Landsat 7 satellite image Colors are from Landsat bands 5, 4, and 2 as red, green and blue, respectively. Topographic expression is exaggerated 5X.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive. The Landsat7 Thematic Mapper image used here was provided to the SRTM by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center, Sioux Falls, South Dakota.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

Size: scale varies in this perspective image Location: 23.4 deg. North lat., 69.7 deg. East lon. Orientation: looking northeast Image Data: Landsat Bands 5, 4, 3 as red, green, blue respectively Original Data Resolution: SRTM 30 meters (99 feet) Date Acquired: four days in February, 2000 (SRTM), February 9, 2001 (Landsat)

2001-01-01

13

SRTM Perspective View with Landsat Overlay: Bhuj and Anjar, India  

NASA Technical Reports Server (NTRS)

This perspective view shows the city of Bhuj, India, in the foreground near the right side (dark gray area). Bhuj and many other towns and cities nearby were almost completely destroyed by the January 26, 2001, earthquake in western India. This magnitude 7.6 earthquake was the deadliest in the history of India with some 20,000 fatalities and over a million homes damaged or destroyed. The epicenter of the earthquake was in the area in the upper left corner of this view.

The city of Anjar is in the dark gray area near the top center of the image. Anjar was previously damaged by a magnitude 6.1 earthquake in 1956 that killed 152 people and suffered again in the larger 2001 earthquake. The red hills to the left of the center of the image are the Has and Karo Hills, which reach up to 300 meter (900 feet) elevation. These hills are formed by folded red sandstone layers. Geologists are studying these folded layers to determine if they are related to the fault that broke in the 2001 earthquake. The city of Bhuj was the historical capital of the Kachchh region. Highways and rivers appear as dark lines. Vegetation appears bright green in this false-color Landsat image. The Gulf of Kachchh (or Kutch) is the blue area in the upper right corner of the image, and the gray area on the left side of the image is called the Banni plains.

This three-dimensional perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and an enhanced false-color Landsat 7 satellite image. Colors are from Landsat bands 5, 4, and 2 as red, green and blue, respectively. Topographic expression is exaggerated 5X.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center, Sioux Falls, South Dakota.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise,Washington, DC.

Size: scale varies in this perspective image Location: 23.4 deg. North lat., 69.8 deg. East lon. Orientation: looking East Image Data: Landsat Bands 5, 4, 3 as red, green, blue respectively Original Data Resolution: SRTM 30 meters (99 feet) Date Acquired: four days in February, 2000 (SRTM), February 9, 2001 (Landsat)

2001-01-01

14

Perspective View with Landsat Overlay, Salt Lake City, Utah  

NASA Technical Reports Server (NTRS)

Most of the population of Utah lives just west of the Wasatch Mountains in the north central part of the state. This broad east-northeastward view shows that region with the cities of Ogden, Salt Lake City, and Provo seen from left to right. The Great Salt Lake (left) and Utah Lake (right) are quite shallow and appear greenish in this enhanced natural color view. Thousands of years ago ancient Lake Bonneville covered all of the lowlands seen here. Its former shoreline is clearly seen as a wave-cut bench and/or light colored 'bathtub ring' at several places along the base of the mountain front - evidence seen from space of our ever-changing planet.

This 3-D perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM), a Landsat 5 satellite image mosaic, and a false sky. Topographic expression is exaggerated four times.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive, managed by the U.S. Geological Survey (USGS).

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C.

Size: View width 147 kilometers (91 miles), View distance 38 kilometers (24 miles) Location: 40.7 deg. North lat., 112.0 deg. West lon. Orientation: View 19.5 deg North of East, 20 degrees below horizontal Image Data: Landsat Bands 3, 2, 1 as red, green, blue, respectively. Original Data Resolution: SRTM 1 arcsecond (30 meters or 98 feet), Thematic Mapper 30 meters (98 feet) Date Acquired: February 2000 (SRTM), 1990s (Landsat 5 image mosaic)

2002-01-01

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SRTM Perspective View with Landsat Overlay: Santa Barbara Coastline, California  

NASA Technical Reports Server (NTRS)

This image of the Santa Barbara, California, region provides a beautiful snapshot of the area's rugged mountains and long and varied coastline. Generated using data acquired from the Shuttle Radar Topography Mission (SRTM) and an enhanced Landsat image this is a perspective view toward the northeast, from the Goleta Valley in the foreground to a snow-capped Mount Abel (elevation 2,526 m or 8,286 feet) along the skyline at the left. On a clear day, a pilot might see a similar view shortly before touching down on the east-west runway of the Santa Barbara Airport, seen just to the left of the coastline near the center of image. This area is one of the few places along the U.S. West Coast where because of a south-facing beach, fall and winter sunrises occur over the ocean.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data match the 30-meter(98-foot) resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive. For visualization purposes, topographic heights displayed in this image are exaggerated two times. Colors approximate natural colors.

The elevation data used in this image was acquired by SRTM aboard Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of Earth's land surface. To collect the 3-D SRTM data, engineers added a mast 60 meters (about 200-feet)long, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense, and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif, for NASA's Earth Science Enterprise, Washington, D.C. JPL is a division of the California Institute of Technology in Pasadena.

Location: 34.5 deg. North lat., 119.75 deg. West lon. View: Northeast Scale: Scale Varies in this Perspective Date Acquired: February 16, 2000 SRTM, December 14, 1984 Landsat

2001-01-01

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Perspective View with Landsat Overlay, San Francisco Bay Area, Calif.  

NASA Technical Reports Server (NTRS)

The defining landmarks of San Francisco, its bay and the San Andreas Fault are clearly seen in this computer-generated perspective viewed from the south. Running from the bottom of the scene diagonally up to the left, the trough of the San Andreas Fault is occupied by Crystal Springs Reservoir and San Andreas Lake. Interstate 280 winds along the side of the fault. San Francisco International Airport is the angular feature projecting into the bay just below San Bruno Mountain, the elongated ridge cutting across the peninsula. The hills of San Francisco can be seen beyond San Bruno Mountain and beyond the city, the Golden Gate.

This 3-D perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and an enhanced color Landsat 5satellite image. Topographic expression is exaggerated two times.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C.

Size: scale varies in this perspective image Location: 37.5 deg. North lat., 122.3 deg. West lon. Orientation: looking north Image Data: Landsat Bands 3,2,1 as red, green, blue, respectively Original Data Resolution: SRTM 1 arcsecond (30 meters or 98 feet), Thematic Mapper 1 arcsecond (30 meters or 98 feet) Date Acquired: February 2000 (SRTM)

2002-01-01

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SRTM Perspective View with Landsat Overlay: Santa Barbara, California  

NASA Technical Reports Server (NTRS)

Santa Barbara, California, is often called 'America's Riviera.' It enjoys a Mediterranean climate, a mountain backdrop, and a long and varied coastline. This perspective view of the Santa Barbara region was generated using data from the Shuttle Radar Topography Mission (SRTM) and an enhanced Landsat satellite image. The view is toward the northeast, from the Goleta Valley in the foreground to a snow-capped Mount Abel (elevation 2526 m or 8286 feet) along the skyline. The coast here generally faces south. Consequently, Fall and Winter sunrises occur over the ocean, which is unusual for the U.S. west coast. The Santa Barbara 'back country' is very rugged and largely remains as undeveloped wilderness and an important watershed for local communities. Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data match the 30-meter resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive. For visualization purposes, topographic heights displayed in this image are exaggerated two times. Colors approximate natural colors.

The elevation data used in this image was acquired by SRTM aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of Earth's land surface.

To collect the 3-D SRTM data, engineers added a mast 60 meters (about 200-feet) long, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense, and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif, for NASA's Earth Science Enterprise,Washington, D.C. JPL is a division of the California Institute of Technology in Pasadena.

Location (Isla Vista): 34.41 deg. North lat., 119.85 deg. West lon. View: East Scale: Scale Varies in this Perspective Date Acquired: February 16, 2000 SRTM, December 14, 1984 Landsat

2001-01-01

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Perspective View with Landsat Overlay, Palm Springs, Calif.  

NASA Technical Reports Server (NTRS)

The city of Palm Springs nestles at the base of Mount San Jacinto in this computer-generated perspective viewed from the east. The many golf courses in the area show up as irregular green areas while the two prominent lines passing through the middle of the image are Interstate 10 and the adjacent railroad tracks. The San Andreas Fault passes through the middle of the sandy Indio Hills in the foreground.

This 3-D perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and an enhanced color Landsat 5satellite image. Topographic expression is exaggerated two times.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR)that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise,Washington, D.C.

Size: scale varies in this perspective image Location: 33.8 deg. North lat., 116.3 deg. West lon. Orientation: looking west Image Data: Landsat Bands 3, 2, 1 as red, green, blue, respectively Original Data Resolution: SRTM 1 arcsecond (30 meters or 98 feet), Thematic Mapper 1 arcsecond (30 meters or 98 feet) Date Acquired: February 2000 (SRTM)

2002-01-01

19

SRTM Perspective View with Landsat Overlay: San Jose, Costa Rica  

NASA Technical Reports Server (NTRS)

This perspective view shows the capital city of San Jose, Costa Rica, in the right center of the image (gray area). Rising behind it are the volcanoes Irazu, 3402 meters high (11,161 feet) and Turrialba, 3330 meters high (10,925 feet.)

Irazu is the highest volcano in Costa Rica and is located in the Irazu Volcano National Park, established in 1955. There have been at least 23 eruptions of Irazu since 1723, the most recent during 1963 to 1965. This activity sent tephra and secondary mudflows into cultivated areas, caused at least 40 deaths, and destroyed 400 houses and some factories.

This image was generated in support of the Central American Commission for Environment and Development through an agreement with NASA. The Commission involves eight nations working to develop the Mesoamerican Biological Corridor, an effort to study and preserve some of the most biologically diverse regions of the planet.

This three-dimensional perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and an enhanced false-color Landsat 7 satellite image. Colors are from Landsat bands 5, 4, and 2 as red, green and blue, respectively. Topographic expression is exaggerated 2X.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center, Sioux Falls, South Dakota.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise,Washington, DC.

Size: scale varies in this perspective image Location: 10.0 deg. North lat., 83.8 deg. East lon. Orientation: looking Southeast Image Data: Landsat Bands 5, 4, 3 as red, green, blue respectively Original Data Resolution: SRTM 30 meters (99 feet) Date Acquired: February, 2000 (SRTM)

2001-01-01

20

SRTM Perspective View with Landsat Overlay: Costa Rica Coastal Plain  

NASA Technical Reports Server (NTRS)

This perspective view shows the northern coastal plain of Costa Rica with the Cordillera Central, composed of a number of active and dormant volcanoes, rising in the background. This view looks toward the south over the Rio San Juan, which marks the boundary between Costa Rica and Nicaragua. The smaller river joining Rio San Juan in the center of the image is Rio Sarapiqui, which is navigable upstream as far inland as Puerto Viejo (Old Port) de Sarapiqui at the mountain's base. This river was an important transportation route for those few hardy settlers who first moved into this region, although as recently as 1953 a mere three thatched-roof houses were all that comprised the village of Puerto Viejo.

This coastal plain is a sedimentary basin formed about 50 million years ago composed of river alluvium and lahar (mud and ash flow) deposits from the volcanoes of the Cordillera Central. It comprises the province of Heredia (the smallest of Costa Rica's seven) and demonstrates a wide range of climatic conditions, from warm and humid lowlands to cool and damp highlands, and including the mild but seasonally wet and dry Central Valley.

This image was generated in support of the Central American Commission for Environment and Development through an agreement with NASA. The Commission involves eight nations working to develop the Mesoamerican Biological Corridor, an effort to study and preserve some of the most biologically diverse regions of the planet.

This three-dimensional perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and an enhanced false-color Landsat 7 satellite image. Colors are from Landsat bands 5, 4, and 2 as red, green and blue, respectively. Topographic expression is exaggerated 2X.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center, Sioux Falls, South Dakota.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise,Washington, DC.

Size: scale varies in this perspective image Location: 10.5 deg. North lat., 84.0 deg. East lon. Orientation: looking South Image Data: Landsat Bands 5, 4, 3 as red, green, blue respectively Original Data Resolution: SRTM 30 meters (99 feet) Date Acquired: February, 2000 (SRTM)

2001-01-01

21

Perspective View, Landsat Overlay, Salalah, Oman, Southern Arabian Peninsula  

NASA Technical Reports Server (NTRS)

This perspective view includes the city of Salalah, the second largest city in Oman. The city is located on the broad, generally bright coastal plain and includes areas of green irrigated crops. This view was generated from a Landsat image draped over a preliminary elevation model produced by the Shuttle Radar Topography Mission (SRTM). The edges of the dataset are to the upper right, left, and lower left. The Arabian Sea (lower right) is represented by the blue false-colored area. Vertical exaggeration of topography is 3X.

This scene illustrates how topography determines local climate and, in turn, where people live. The Arabian Peninsula is very arid. However, the steep escarpment of the Qara Mountains wrings moisture from the summer monsoons allowing for growth of natural vegetation (green along the mountain fronts and in the canyons), and soil development (dark brown areas), as well as cultural development of the coastal plain. The monsoons also provide moisture for Frankincense trees growing on the desert (north) side of the mountains. In ancient times, incense derived from the sap of the Frankincense tree was the basis for an extremely lucrative trade.

Landsat satellites have provided visible light and infrared images of the Earth continuously since 1972. SRTM topographic data match the 30-meter (99-foot)spatial resolution of most Landsat images and provide a valuable complement for studying the historic and growing Landsat data archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM project by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center,Sioux Falls, South Dakota.

Elevation data used in this image was acquired by SRTM aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar(SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

Size: 45 kilometers (28 miles) across x 178 kilometers (110 miles) distance Location: 17 deg. North lat., 54 deg. East lon. Orientation: North toward upper left Image Data: Landsat bands 1, 2+4, 3 in blue, green, red Date Acquired: February 15, 2000 (SRTM), November 9, 1999 (Landsat) Image: NASA/JPL/NIMA

2000-01-01

22

SRTM Perspective View with Landsat Overlay: Rann of Kachchh, India  

NASA Technical Reports Server (NTRS)

The earthquake that struck western India on January 26,2001, was the country's strongest in the past 50 years. This perspective view shows the area of the earthquake's epicenter in the lower left corner. The southern Rann of Kachchh appears in the foreground. The Rann is an area of low-lying salt flats that shows up with various shades of white and blue in this false-color Landsat image. The gray area on the middle of the image is called the Banni plains.

The darker blue spots and curving lines in the Rann and the Banni plains are features that appeared after the January earthquake. Their true colors are shades of white and gray, but the infrared data used in the image gives them a blue or turquoise color. These features are the effects of liquefaction of wet soil, sand and mud layers caused by the shaking of the earthquake. The liquefaction beneath the surface causes water to be squeezed out at the surface forming mud volcanoes, sand blows and temporary springs. Some of the residents of this dry area were hopeful that they could use the water, but they found that the water was too salty in almost every place where it came to the surface.

The city of Bhuj, India, appears as a gray area in the upper right of the image. Bhuj and many other towns and cities nearby were almost completely destroyed by the January 2001 earthquake. This magnitude 7.7 earthquake was the deadliest in the history of India with some 20,000 fatalities and over a million homes damaged or destroyed. The city of Bhuj was the historical capital of the Kachchh region. Highways and rivers appear as dark lines. Vegetation appears bright green in this false-color Landsat image.

The city of Anjar is in the dark gray area near the upper left of the image. Previously damaged by a magnitude 6.1 earthquake in 1956 that killed 152people, Anjar suffered again in the larger 2001 earthquake.

The red hills in the center of the image are the Has and Karo Hills, which reach up to 300 m (900 feet) elevation. Geologists are studying the folded red sandstone layers that form these hills to determine if they are related to the fault that broke in the 2001 earthquake.

This three-dimensional perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and an enhanced false-color Landsat 7 satellite image. Colors are from Landsat bands 5, 4, and 2 as red, green and blue, respectively. Topographic expression is exaggerated 5X.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter resolution of most Landsat images and will substantially help in analyses of the large and growing Landsat image archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center, Sioux Falls, South Dakota.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

Size: scale varies in this perspective image Location: 23.5 deg. North lat., 69.9 deg. East lon. Orientation: looking Southwest Image Data: Landsat Bands 5, 4, 3 as red, gr

2001-01-01

23

SRTM Perspective View with Landsat Overlay: San Joaquin Valley, California  

NASA Technical Reports Server (NTRS)

San Joaquin, the name given to the southern portion of California's vast Central Valley, has been called the world's richest agricultural valley. In this perspective view generated using data from the Shuttle Radar Topography Mission and an enhanced Landsat image, we are looking toward the southwest over a checkerboard pattern of agricultural fields. Mt. Pinos, a popular location for stargazing at 2,692 meters (8,831 feet) looms above the valley floor and is visible on the left side of the image. The productive southern San Joaquin is in reality a desert, averaging less than 12.7 cm (5 inches) of rain per year. Through canals and irrigation, the region nurtures some two hundred crops including grapes, figs, apricots, oranges, and more than 4,047 square-km (1,000,000 acres) of cotton. The California Aqueduct, transporting water from the Sacramento River Delta through the San Joaquin, runs along the base of the low-lying Wheeler Ridge on the left side of the image. The valley is not all agriculture though. Kern County, near the valley's southern end, is the United States' number one oil producing county, and actually produces more crude oil than Oklahoma. For visualization purposes, topographic heights displayed in this image are exaggerated two times. Colors, from Landsat data, approximate natural color.

The elevation data used in this image was acquired by SRTM aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of Earth's land surface. To collect the 3-D SRTM data, engineers added a mast 60 meters (about 200 feet)long, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense, and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif, for NASA's Earth Science Enterprise,Washington, D.C. JPL is a division of the California Institute of Technology in Pasadena.

Location: 35.08 deg. North lat., 119.00 deg. West lon. View: Toward the Southwest Scale: Scale Varies in this Perspective Date Acquired: February 16, 2000 SRTM, December 14, 1984 Landsat

2000-01-01

24

Budapest, Hungary, Perspective View, SRTM Elevation Model with Landsat Overlay  

NASA Technical Reports Server (NTRS)

After draining the northern flank of the Alps Mountains in Germany and Austria, the Danube River flows east as it enters this west-looking scene (upper right) and forms the border between Slovakia and Hungary. The river then leaves the border as it enters Hungary and transects the Transdanubian Mountains, which trend southwest to northeast. Upon exiting the mountains, the river turns southward, flowing past Budapest (purplish blue area) and along the western margin of the Great Hungarian Plain.

South and west of the Danube, the Transdanubian Mountains have at most only about 400 meters (about 1300 feet) of relief but they exhibit varied landforms, which include volcanic, tectonic, fluvial (river), and eolian (wind) features. A thick deposit of loess (dust deposits likely blown from ancient glacial outwash) covers much of this area, and winds from the northwest, funneled between the Alps and the Carpathian Mountains, are apparently responsible for a radial pattern of erosional streaks across the entire region.

This image was generated from a Landsat satellite image draped over an elevation model produced by the Shuttle Radar Topography Mission (SRTM). The view uses a 3-times vertical exaggeration to enhance topographic expression. The false colors of the scene result from displaying Landsat bands 1, 4, and 7 in blue, green, and red, respectively. Band 1 is visible blue light, but bands 4 and 7 are reflected infrared light. This band combination maximizes color contrasts between the major land cover types, namely vegetation (green), bare ground (red), and water (blue). Shading of the elevation model was used to further highlight the topographic features.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

View Size: 133 kilometers (82 miles) wide, 90 kilometers (56 miles) distance Location: 47.5 degrees North latitude, 19.0 degrees East longitude Orientation: Looking West, 15 degrees down from horizontal, 3X vertical exaggeration Image Data: Landsat Bands 1, 4, 7 as blue, green, red respectively Date Acquired: February 2000 (SRTM), October 11, 1990 (Landsat)

2004-01-01

25

Mount Ararat, Turkey, Perspective with Landsat Image Overlay  

NASA Technical Reports Server (NTRS)

This perspective view shows Mount Ararat in easternmost Turkey, which has been the site of several searches for the remains of Noah's Ark. The main peak, known as Great Ararat, is the tallest peak in Turkey, rising to 5165 meters (16,945 feet). This southerly, near horizontal view additionally shows the distinctly conically shaped peak known as 'Little Ararat' on the left. Both peaks are volcanoes that are geologically young, but activity during historic times is uncertain.

This image was generated from a Landsat satellite image draped over an elevation model produced by the Shuttle Radar Topography Mission (SRTM). The view uses a 1.25-times vertical exaggeration to enhance topographic expression. Natural colors of the scene are enhanced by image processing, inclusion of some infrared reflectance (as green) to highlight the vegetation pattern, and inclusion of shading of the elevation model to further highlight the topographic features.

Volcanoes pose hazards for people, the most obvious being the threat of eruption. But other hazards are associated with volcanoes too. In 1840 an earthquake shook the Mount Ararat region, causing an unstable part of mountain's north slope to tumble into and destroy a village. Visualizations of satellite imagery when combined with elevation models can be used to reveal such hazards leading to disaster prevention through improved land use planning.

But the hazards of volcanoes are balanced in part by the benefits they provide. Over geologic time volcanic materials break down to form fertile soils. Cultivation of these soils has fostered and sustained civilizations, as has occurred in the Mount Ararat region. Likewise, tall volcanic peaks often catch precipitation, providing a water supply to those civilizations. Mount Ararat hosts an icefield and set of glaciers, as seen here in this late summer scene, that are part of this beneficial natural process

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

View Size: 124 kilometers (77 miles) wide, 148 kilometers (92 miles) distance Location: 39.7 degrees North latitude, 44.3 degrees East longitude Orientation: Looking South, 2 degrees down from horizontal, 1.25X vertical exaggeration Image Data: Landsat Bands 1, 2+4, 3 as blue, green, red respectively Date Acquired: February 2000 (SRTM), August 31, 1989 (Landsat)

2004-01-01

26

Pasadena, California Perspective View with Aerial Photo and Landsat Overlay  

NASA Technical Reports Server (NTRS)

This perspective view shows the western part of the city of Pasadena, California, looking north towards the San Gabriel Mountains. Portions of the cities of Altadena and La Canada-Flintridge are also shown. The image was created from three datasets: the Shuttle Radar Topography Mission (SRTM) supplied the elevation data; Landsat data from November 11, 1986 provided the land surface color (not the sky) and U. S. Geological Survey digital aerial photography provides the image detail. The Rose Bowl, surrounded by a golf course, is the circular feature at the bottom center of the image. The Jet Propulsion Laboratory, is the cluster of large buildings north of the Rose Bowl at the base of the mountains. A large landfill, Scholl Canyon, is the smooth area in the lower left corner of the scene.

This image shows the power of combining data from different sources to create planning tools to study problems that affect large urban areas. In addition to the well-known earthquake hazards, Southern California is affected by a natural cycle of fire and mudflows. Wildfires strip the mountains of vegetation, increasing the hazards from flooding and mudflows for several years afterwards. Data such as shown on this image can be used to predict both how wildfires will spread over the terrain and also how mudflows will be channeled down the canyons.

For a full-resolution, annotated version of this image, please select Figure 1, below: [figure removed for brevity, see original site]

The Shuttle Radar Topography Mission (SRTM), launched on February 11,2000, uses the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging antenna and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) and the German (DLR) and Italian (ASI) space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

Size: 5.8 km (3.6 miles) x 10 km (6.2 miles) Location: 34.16 deg. North lat., 118.16 deg. West lon. Orientation: Looking North Original Data Resolution: SRTM, 30 meters; Landsat, 30 meters; Aerial Photo, 3 meters (no vertical exaggeration) Date Acquired: February 16, 2000

2000-01-01

27

Los Alamos Fires From Landsat 7  

NASA Technical Reports Server (NTRS)

On May 9, 2000, the Landsat 7 satellite acquired an image of the area around Los Alamos, New Mexico. The Landsat 7 satellite acquired this image from 427 miles in space through its sensor called the Enhanced Thematic Mapper Plus (ETM+). Evident within the imagery is a view of the ongoing Cerro Grande fire near the town of Los Alamos and the Los Alamos National Laboratory. Combining the high-resolution (30 meters per pixel in this scene) imaging capacity of ETM+ with its multi-spectral capabilities allows scientists to penetrate the smoke plume and see the structure of the fire on the surface. Notice the high-level of detail in the infrared image (bottom), in which burn scars are clearly distinguished from the hotter smoldering and flaming parts of the fire. Within this image pair several features are clearly visible, including the Cerro Grande fire and smoke plume, the town of Los Alamos, the Los Alamos National Laboratory and associated property, and Cerro Grande peak. Combining ETM+ channels 7, 4, and 2 (one visible and two infrared channels) results in a false color image where vegetation appears as bright to dark green (bottom image). Forested areas are generally dark green while herbaceous vegetation is light green. Rangeland or more open areas appear pink to light purple. Areas with extensive pavement or urban development appear light blue or white to purple. Less densely-developed residential areas appear light green and golf courses are very bright green. The areas recently burned appear black. Dark red to bright red patches, or linear features within the burned area, are the hottest and possibly actively burning areas of the fire. The fire is spreading downslope and the front of the fire is readily detectable about 2 kilometers to the west and south of Los Alamos. Combining ETM+ channels 3, 2, and 1 provides a true-color image of the greater Los Alamos region (top image). Vegetation is generally dark to medium green. Forested areas are very dark green while herbaceous vegetation is medium green. Rangeland or more open areas appear as tan or light brown. Areas with extensive pavement or urban development appear white to light green. Less densely-developed residential areas appear medium green and golf courses are medium green. The fires and areas recently burned are obscured by smoke plumes which are white to light blue. Landsat 7 data are archived and available from EDC. Image by Rob Simmon, Earth Observatory, NASA Goddard Space Flight Center. Data courtesy Randy McKinley, EROS Data Center (EDC)

2002-01-01

28

SRTM Perspective View with Landsat Overlay: Syracuse, Oneida Lake, Upstate New York  

NASA Technical Reports Server (NTRS)

In the lower center of this perspective view of upstate New York, the city of Syracuse hugs the southeastern banks (top right side) of Lake Onondaga, the smaller of the two dark features that dominate the scene. The view is toward the east. The urban area appears bright in stark contrast to the dark waterways and the greens, browns and yellows of the vegetated areas. Both of the two black features are lakes. Oneida Lake , the larger of the two is to the left of the scene center. About 1/3 of the way between Lakes Onondaga and Oneida are the triangular shaped runways of the Syracuse Hancock International Airport. The Adirondack Mountains are to the upper left while the less rugged Catskills can be seen in the upper right. A faint outline of the Mohawk River can be seen as threads its way down from the Adirondacks toward the city of Rome, the bright area in the valley between the lake and the Adirondacks. The Erie Canal and the Oswego River are part of the network of waterways seen in the left image foreground.

Fall foliage in a variety of colors can be seen in the Landsat data used here. Redder vegetation generally occurs at higher elevations and toward the north (left), especially in the Adirondack Mountains. The back edge of the data set forms a false skyline. The image was generated using topographic data from SRTM and enhanced true-color Landsat 5 satellite images. Topographic shading in the image was enhanced with false shading derived from the elevation model. Topographic expression is exaggerated 6X. Syracuse lies at the geographic center of the state of New York and has been the site of its state fair for most of that event's 154 years. It is located in an agricultural and resort area. The yellowish rectangular features in the foreground of the image are farmlands. Parts of Skaneateles and Otisco Lakes, some of central New York's Finger Lakes, can be seen in the bottom right corner of the image.

Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian Space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

Size: 200 kilometers View Distance x 280 kilometers View Width (Background) (125 by 175 miles) Location: 43.1 deg. North Lat, 76.1.deg. West Lon. (Syracuse) Orientation: View is toward the east Date Acquired: SRTM, February 13, 2000; Landsat, various

2000-01-01

29

The use of radar and LANDSAT data for mineral and petroleum exploration in the Los Andes region, Venezuela  

NASA Technical Reports Server (NTRS)

A geological study of a 27,500 sq km area in the Los Andes region of northwestern Venezuela was performed which employed both X-band radar mosaics and computer processed Landsat images. The 3.12 cm wavelength radar data were collected with horizontal-horizontal polarization and 10 meter spatial resolution by an Aeroservices SAR system at an altitude of 12,000 meters. The radar images increased the number of observable suspected fractures by 27 percent over what could be mapped by LANDSAT alone, owing mostly to the cloud cover penetration capabilities of radar. The approximate eight fold greater spatial resolution of the radar images made possible the identification of shorter, narrower fractures than could be detected with LANDSAT data alone, resulting in the discovery of a low relief anticline that could not be observed in LANDSAT data. Exploration targets for petroleum, copper, and uranium were identified for further geophysical work.

Vincent, R. K.

1980-01-01

30

Landsat: Space Activities for Students  

ERIC Educational Resources Information Center

An aerospace education activity is described which is suitable for grades 3-12. Students piece together several images from the Landsat satellite to make a mosaic of their state. From the mosaic clear acetate overlay maps can be made relating to such subjects as agriculture, geology, hydrology, or urban planning. (BB)

Marks, Steven K.

1979-01-01

31

Landsat 8  

USGS Publications Warehouse

The Landsat era that began in 1972 will continue into the future, since the February 2013 launch of the Landsat Data Continuity Mission (renamed Landsat 8 on May 30, 2013). The Landsat 8 satellite provides 16-bit high-quality land-surface data, with instruments advancing future measurement capabilities while ensuring compatibility with historical Landsat data. The Operational Land Imager sensor collects data in the visible, near infrared, and shortwave infrared wavelength regions as well as a panchromatic band. Two new spectral bands have been added: a deep-blue band for coastal water and aerosol studies (band 1), and a band for cirrus cloud detection (band 9). A Quality Assurance band is also included to indicate the presence of terrain shadowing, data artifacts, and clouds. The Thermal Infrared Sensor collects data in two long wavelength thermal infrared bands and has a 3-year design life.

U.S. Geological Survey

2013-01-01

32

Implementing declarative overlays  

Microsoft Academic Search

Overlay networks are used today in a variety of distributed systems ranging from file-sharing and storage systems to communication infrastructures. However, designing, building and adapting these overlays to the intended application and the target environment is a difficult and time consuming process.To ease the development and the deployment of such overlay networks we have implemented P2, a system that uses

Boon Thau Loo; Tyson Condie; Joseph M. Hellerstein; Petros Maniatis; Timothy Roscoe; Ion Stoica

2005-01-01

33

Landsat Data Resources  

NSDL National Science Digital Library

This site from NASA provides a number of resources for obtaining Landsat digital data. Included are links for ordering Landsat 7 data as well as sources of Landsat 4, 5 and other related and heritage land remote sensing data.

Nasa

34

New holographic overlays  

NASA Astrophysics Data System (ADS)

This paper discusses a new type of holographic overlay, FLASHPRINT, which may be used in both security and packaging applications. Unlike the more common embossed holograms currently used, FLASHPRINT leads to reduced set-up costs and offers a simpler process. This reduces the long lead times characteristic of the existing technology and requires the customer to provide only two-dimensional artwork. The overlay material contains a covert 2-D image. The image may be switched on or off by simply tilting the overlay in a light source. The overlay is replayed in the 'on' position to reveal the encoded security message as a highly saturated gold colored image. This effect is operable for a wide range of lighting conditions and viewing geometries. In the 'off' position the overlay is substantially transparent. These features make the visual effect of the overlay attractive to incorporate into product design. They may be laminated over complex printed artwork such as labels and security passes without masking the printed message. When switched 'on' the image appears both sharp and more than seven times brighter than white paper. The image remains sharp and clear even in less favorable lighting conditions. Although the technique offers a low set-up cost for the customer, through its simplicity, it remains as technically demanding and difficult to counterfeit as any holographic process.

Hopwood, Anthony I.

1991-10-01

35

Landsat Legacy  

NASA Technical Reports Server (NTRS)

The Landsat resources survey system spawned a number of companies engaged in commercial applications of remote sensing, among them International Imaging Systems (I2S). With initial NASA assistance, I2S has provided remote sensing hardware and software to several foreign countries, developed meteorological analysis systems, medical diagnostic software and scanning equipment for government and commercial use. Latest product is an advanced image-based photogrammetric system employing digital technology - not optical or mechanical systems - to generate terrain elevation data and other processing functions. Called PRI2SM, it compensates automatically for topographic relief displacement, is cheaper, faster, and easier to use and maintain. Company product line includes four major areas: image processing equipment for Earth Resources Management; meteorological analysis systems; satellite ground processing systems; and digital photogrammetric mapping systems.

1991-01-01

36

Inter-Overlay Cooperation in High-Bandwidth Overlay Multicast  

Microsoft Academic Search

The cooperation of end users can be exploited to boost the performance of high-bandwidth multicast. Whileintra- overlay cooperation, the mechanism for cooperation within a single overlay (multicast group), has been extensively studied, little attention has been paid tointer-overlay coop- eration. In this paper we explore the possibility and effects of cooperation among co-existing heterogeneous overlays in the context of live

Guang Tan; Stephen A. Jarvis

2006-01-01

37

Overlay metrology tool calibration  

Microsoft Academic Search

In a previous publication, we introduced Blossom, a multi-layer overlay mark (Ausschnitt, et al. 2006, [1]). Through further testing carried out since that publication, Blossom has been shown to meet the requirements on current design rules (Ausschnitt, et al. 2007, [2]), while giving some unique benefits. However, as future design rules shrink, efforts must be made now to ensure the

L. A. Binns; P. Dasari; N. P. Smith; G. Ananew; H. Fink; C. P. Ausschnitt; J. Morningstar; C. Thomison; R. J. Yerdon

2007-01-01

38

Guest Editorial Overlay networks  

E-print Network

(VM) to apply to communica- tion systems. They go by many names, including virtual private networksGuest Editorial Overlay networks Virtual networks (VNs) extend the abstraction of virtual memory avoiding recoding a real im- plementation into a simulation system. Virtualizing a network raises issues

Touch, Joe

39

Landsat-1 and Landsat-2 flight evaluation  

NASA Technical Reports Server (NTRS)

The flight performance of Landsat 1 and Landsat 2 is analyzed. Flight operations of the satellites are briefly summarized. Other topics discussed include: orbital parameters; power subsystem; attitude control subsystem; command/clock subsystem; telemetry subsystem; orbit adjust subsystem; magnetic moment compensating assembly; unified s-band/premodulation processor; electrical interface subsystem; thermal subsystem; narrowband tape recorders; wideband telemetry subsystem; attitude measurement sensor; wideband video tape recorders; return beam vidicon; multispectral scanner subsystem; and data collection subsystem.

1975-01-01

40

A Landsat study of water quality in Lake Okeechobee  

NASA Technical Reports Server (NTRS)

This paper uses multiple regression techniques to investigate the relationship between Landsat radiance values and water quality measurements. For a period of over one year, the Central and Southern Florida Flood Control District sampled the water of Lake Okeechobee for chlorophyll, carotenoids, turbidity, and various nutrients at the time of Landsat overpasses. Using an overlay map of the sampling stations, Landsat radiance values were measured from computer compatible tapes using a GE image 100 and averaging over a 22-acre area at each station. These radiance values in four bands were used to form a number of functions (powers, logarithms, exponentials, and ratios), which were then compared with the ground measurements using multiple linear regression techniques. Several dates were used to provide generality and to study possible seasonal variations. Individual correlations were presented for the various water quality parameters and best fit equations were examined for chlorophyll and turbidity. The results and their relationship to past hydrological research were discussed.

Gervin, J. C.; Marshall, M. L.

1976-01-01

41

Overlay similarity: a new overlay index for metrology tool and scanner overlay fingerprint methodology  

NASA Astrophysics Data System (ADS)

For different CD metrologies like average CD from CD SEM and optical CD (OCD) from scatterometry, CD point-to-point R2 has been well adopted as the CD correlation index. For different overlay metrologies like image-based box-in-box overlay and scatterometry-based overlay, we propose the cosine similarity as the correlation index of overlay. The cosine similarity is a measure of similarity between two vectors of n dimensions by finding the cosine of the angle between them, often used to compare documents in text mining. It has been widely used in web and document search engines and can be used as the similarity index of overlay tool-to-tool matching and scanner tool-to-tool or day-to-day fingerprint. In this paper, we demonstrate that the cosine similarity has a very high sensitivity to the overly tool performance. We compared the similarities of three generations (A1, A2, A3) of the overlay tools of venders A and B and found that after target re-training and TIS correction on each tool A1 similarity to A3 can be improved from 0.9837 to 0.9951. Overlay point-to-point matching with A3 vs. A1 can be reduced from 4.8 to 2.1 nm. The tool precision similarities, i.e. tool self best similarity, for A1, A2, A3 and B are 0.9986, 0.9990, 0.9995, and 0.9994 respectively. From this table, we demonstrate that we can use old-generation overlay tool with suitable hardware maintenance, to match to the latest-generation overlay tool.

Ke, Chih-Ming; Kao, Ching-Pin; Wang, Yu-Hsi; Hu, Jimmy; Chang, Chen-Yu; Tsai, Ya-Jung; Yen, Anthony; Lin, Burn J.

2009-03-01

42

Optimized Overlay Metrology Marks: Theory and Experiment  

E-print Network

1 Optimized Overlay Metrology Marks: Theory and Experiment M. Adel, M. Ghinovker, B. Golovanevsky a detailed analysis of overlay metrology mark and find the mapping between various properties of mark. Keywords Overlay metrology, overlay mark, Cramer-Rao lower bound, Fisher information matrix, box

Markovitch, Shaul

43

Landsat and water pollution  

NASA Technical Reports Server (NTRS)

Report presents data derived from satellite images predicting pollution loads after rainfall. It explains method for converting Landsat images of Eastern United States into cover maps for Baltimore/five county region.

Castruccio, P.; Fowler, T.; Loats, H., Jr.

1979-01-01

44

Landsat Earth Monitor.  

ERIC Educational Resources Information Center

The uses of NASA's Landsat in the areas of cartography, flood control, agricultural inventory, land use mapping, water runoff, urban planning, erosion, geology, and water quality monitoring are illustrated. (BB)

Haggerty, James J.

1979-01-01

45

Landsat's international partners  

USGS Publications Warehouse

Since the launch of the first Landsat satellite 40 years ago, International Cooperators (ICs) have formed a key strategic alliance with the U.S. Geological Survey (USGS) to not only engage in Landsat data downlink services but also to enable a foundation for scientific and technical collaboration. The map below shows the locations of all ground stations operated by the United States and IC ground station network for the direct downlink and distribution of Landsat 5 (L5) and Landsat 7 (L7) image data. The circles show the approximate area over which each station has the capability for direct reception of Landsat data. The red circles show the components of the L5 ground station network, the green circles show components of the L7 station network, and the dashed circles show stations with dual (L5 and L7) status. The yellow circles show L5 short-term ("campaign") stations that contribute to the USGS Landsat archive. Ground stations in South Dakota and Australia currently serve as the primary data capture facilities for the USGS Landsat Ground Network (LGN). The Landsat Ground Station (LGS) is located at the USGS Earth Resources Observation and Science (EROS) Center in Sioux Falls, South Dakota. The Alice Springs (ASN) ground station is located at the Geoscience Australia facility in Alice Springs, Australia. These sites receive the image data, via X-band Radio Frequency (RF) link, and the spacecraft housekeeping data, via S-band RF link. LGS also provides tracking services and a command link to the spacecrafts.

Byrnes, Raymond A.

2012-01-01

46

Familiarization with LANDSAT imagery  

NASA Technical Reports Server (NTRS)

Learning objectives of the activities provided include: (1) reading the annotation of a LANDSAT image; (2) becoming acquainted with the characteristics of 1:1,000,000 scale transparencies and prints of MSS images; (3) noting the general information visible in LANDSAT photo products; (4) observing changes of appearance of any ground feature or class in the black and white images made from the four MSS bands and the characteristic color of each class in color composites; (5) determining the degree to which a LANDSAT image meets map accuracy standards and can be fitted to map projections; (6) assessing the effects of LANDSAT enlargements and scale changes and of the limitations of satellite resolution relative to aerial photos; (7) observing the influence of time of acquisition (season) on a scene; (8) getting a feel for image quality as dependent on processing and photoreproduction; (9) appreciating the characteristics of the RBV and thermal band imagery obtained from LANDSAT-3; and (10) becoming familiar with certain attributes of adjacent LANDSAT images which permit them to be joined in mosaics and to be viewed in stereo.

1982-01-01

47

Landsat: building a strong future  

USGS Publications Warehouse

Conceived in the 1960s, the Landsat program has experienced six successful missions that have contributed to an unprecedented 39-year record of Earth Observations that capture global land conditions and dynamics. Incremental improvements in imaging capabilities continue to improve the quality of Landsat science data, while ensuring continuity over the full instrument record. Landsats 5 and 7 are still collecting imagery. The planned launch of the Landsat Data Continuity Mission in December 2012 potentially extends the Landsat record to nearly 50 years. The U.S. Geological Survey (USGS) Landsat archive contains nearly three million Landsat images. All USGS Landsat data are available at no cost via the Internet. The USGS is committed to improving the content of the historical Landsat archive though the consolidation of Landsat data held in international archives. In addition, the USGS is working on a strategy to develop higher-level Landsat geo- and biophysical datasets. Finally, Federal efforts are underway to transition Landsat into a sustained operational program within the Department of the Interior and to authorize the development of the next two satellites — Landsats 9 and 10.

Loveland, Thomas R.; Dwyer, John L.

2012-01-01

48

To Overlay or Not To Overlay Roch Guerin  

E-print Network

at thickening the waist failed because § A big solution for a small problem § The best solution rather than" network layer #12;The Pro-Overlay "Arguments" Previous attempts at thickening the waist have failed? § Small data path cost § Significant control path (management) cost The IntServ/RSVP debacle § Hardly

Guerin, Roch

49

Landsat Radiometry Project  

NASA Technical Reports Server (NTRS)

This final report summarizes three years of work characterizing the radiometry of the Landsat 4, 5 and 7 Thematic Mappers. It is divided into six sections that are representative of the major areas of effort: 1) Internal Calibrator Lamp Monitoring; 2) Vicarious Calibration; 3) Relative Gain Analysis; 4) Outgassing; 5) Landsat 4 Absolute Calibration; and 6) Landsat 5 Scene Invariant Analysis. Each section provides a summary overview of the work that has been performed at SDSU. Major results are highlighted. In several cases, references are given to publications that have developed from this work, Several team members contributed to this report: Tim Ruggles, Dave Aaron, Shriharsha Madhavan, Esad Micijevic, Cory Mettler, and Jim Dewald. At the end of the report is a summary section.

2005-01-01

50

LANDSAT-D Investigations Workshop  

NASA Technical Reports Server (NTRS)

Viewgraphs are presented which highlight LANDSAT-D project status and ground segment; early access TM processing; LANDSAT-D data acquisition and availability; LANDSAT-D performance characterization; MSS pre-NOAA characterization; MSS radiometric sensor performance (spectral information, absolute calibration, and ground processing); MSS geometric sensor performance; and MSS geometric processing and calibration.

1982-01-01

51

Symbiotic Relationships in Internet Routing Overlays  

Microsoft Academic Search

We propose to construct routing overlay networks us- ing the following principle: that overlay edges should be based on mutual advantage between pairs of hosts. Upon this principle, we design, implement, and evaluate Peer- Wise, a latency-reducing overlay network. To show the feasibility of PeerWise, we must show first that mutual advantage exists in the Internet: perhaps contrary to ex-

Cristian Lumezanu; Randolph Baden; Dave Levin; Neil Spring; Bobby Bhattacharjee

2009-01-01

52

Monitoring gypsy moth defoliation by applying change detection techniques to Landsat imagery  

NASA Technical Reports Server (NTRS)

The overall objective of a research effort at NASA's Goddard Space Flight Center is to develop and evaluate digital image processing techniques that will facilitate the assessment of the intensity and spatial distribution of forest insect damage in Northeastern U.S. forests using remotely sensed data from Landsats 1, 2 and C. Automated change detection techniques are presently being investigated as a method of isolating the areas of change in the forest canopy resulting from pest outbreaks. In order to follow the change detection approach, Landsat scene correction and overlay capabilities are utilized to provide multispectral/multitemporal image files of 'defoliation' and 'nondefoliation' forest stand conditions.

Williams, D. L.; Stauffer, M. L.

1978-01-01

53

Landsat Data Continuity Mission  

USGS Publications Warehouse

The Landsat Data Continuity Mission (LDCM) is a partnership formed between the National Aeronautics and Space Administration (NASA) and the U.S. Geological Survey (USGS) to place the next Landsat satellite in orbit in January 2013. The Landsat era that began in 1972 will become a nearly 41-year global land record with the successful launch and operation of the LDCM. The LDCM will continue the acquisition, archiving, and distribution of multispectral imagery affording global, synoptic, and repetitive coverage of the Earth's land surfaces at a scale where natural and human-induced changes can be detected, differentiated, characterized, and monitored over time. The mission objectives of the LDCM are to (1) collect and archive medium resolution (30-meter spatial resolution) multispectral image data affording seasonal coverage of the global landmasses for a period of no less than 5 years; (2) ensure that LDCM data are sufficiently consistent with data from the earlier Landsat missions in terms of acquisition geometry, calibration, coverage characteristics, spectral characteristics, output product quality, and data availability to permit studies of landcover and land-use change over time; and (3) distribute LDCM data products to the general public on a nondiscriminatory basis at no cost to the user.

U.S. Geological Survey

2012-01-01

54

Quayle saves Landsat program  

NASA Astrophysics Data System (ADS)

With a last-minute budget reprieve from the Bush administration, Landsats 4 and 5, the sole public U.S. source of detailed satellite images of Earth, have another six months of life. The impending shutoff of the satellites on March 31 without an infusion of funds has focused attention on the public—private partnership that manages the Landsat program.EOSAT , Inc., the private corporation that operates Landsats 4 and 5, needs $9.4 million to maintain the satellites until the end of the fiscal year in October. As it has in previous years, t h e Reagan administration included no money in its FY 1989 budget to keep the spacecraft working, a n d the Bush administration has not amended that policy. Congress has restored operating funds in the past, but this time it was the National Space Council, headed by Vice President Dan Quayle, that released a statement saying that federal agencies that are many of the biggest customers for remote sensing data from the satellites will pay at least some of the costs. Under the plan the rest would be supplied by EOSAT, which markets Landsat data.

Maggs, William Ward

55

Landsat: Mt. Redoubt  

USGS Multimedia Gallery

Landsat 5 image of the Mt. Redoubt area on March 26, 2009 at 1:07 PM AKDT. The false color image shows the large brown ash cloud extending over the Cook Inlet and the western Kenai peninsula (right sid of image). The image also shows a whiter steam and gas plume rising from the summit of Redoubt Vol...

2009-04-06

56

Landsat US standard catalog  

NASA Technical Reports Server (NTRS)

The U.S. Standard Catalog lists imagery of the continental U.S., Alaska and Hawaii acquired by Landsat 1 and 2 which has been processed and input to the data files during the referenced month. Data, such as date acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found is also given.

1975-01-01

57

Finding international Landsat data online  

USGS Publications Warehouse

The Global Land Information System (GLIS) lists Landsat multispectral scanner (MSS) and thematic mapper (TM) data available from the participating international ground stations shown below. These databases of the Landsat Ground Station Operations Working Group (LGSOWG) can be searched, but not ordered, using GLIS. To order Landsat scenes identified on the GLIS data search, contact the international ground station where those scenes are available, indicated by the second character of the Entity ID.

Geological Survey (U.S.)

1997-01-01

58

Landsat7 and Landsat5 thermal band calibration updates  

Microsoft Academic Search

Landsat-7 ETM+, launched in April 1999, and Landsat-5 TM, launched in 1984, both have a single thermal band. Both instruments' thermal band calibrations have been updated: ETM+ in 2001 for a pre-launch calibration error and TM in 2007 for data acquired since the current era of vicarious calibration has been in place (1999). This year, the vicarious calibration teams have

Julia A. Barsi; Brian L. Markham; John R. Schott; Simon J. Hook; Nina G. Raqueno

2009-01-01

59

Meeting overlay requirements for future technology nodes with indie overlay metrology  

Microsoft Academic Search

As a consequence of the shrinking sizes of the integrated circuit structures, the overlay budget shrinks as well. Overlay is traditionally measured with relatively large test structures which are located in the scribe line of the exposure field, in the four corners. Although the performance of the overlay metrology tools has improved significantly over time it is questionable if this

Bernd Schulz; Rolf Seltmann; Jens Busch; Fritjof Hempel; Eric Cotte; Benjamin Alles

2007-01-01

60

Landsat Data Continuity Mission  

NASA Technical Reports Server (NTRS)

The Landsat Data Continuity Mission (LDCM) is currently under development and is on schedule to launch the 8th satellite in the Landsat series in December of 2012. LDCM is a joint project between the National Aeronautics and Space Administration (NASA) and the United States Geological Survey (USGS). NASA is responsible for developing and launching the flight hardware and on-orbit commissioning and USGS is responsible for developing the ground system and operating the system onorbit after commissioning. Key components of the flight hardware are the Operational Land Imager (OLI), nearing completion by Ball Aerospace & Technologies Corp in Boulder, CO, the Thermal Infrared Sensor (TIRS), being built by NASA's Goddard Space Flight Center and the spacecraft, undergoing integration at Orbital Sciences Corp in Gilbert, Arizona. The launch vehicle will be an Atlas-5 with launch services provided by NASA's Kennedy Space Center. Key ground systems elements are the Mission Operations Element, being developed by the Hammers Corporation, and the Collection Activity Planning Element, Ground Network Element, and Data Processing and Archive System, being developed internally by the USGS Earth Resources Observations and Science (EROS) Center. The primary measurement goal of LDCM is to continue the global coverage of moderate spatial resolution imagery providing continuity with the existing Landsat record. The science goal for this imagery is to monitor land use and land cover, particularly as it relates to global climate change. Together the OLI and TIRS instruments on LDCM replace the ETM+ instrument on Landsat-7 with significant enhancements. The OLI is a pushbroom design instrument where the scanning mechanism of the ETM+ is effectively replaced by a long line of detectors. The OLI has 9 spectral bands with similar spatial resolution to ETM+: 7 of them similar to the reflective spectral bands on ETM+ and two new bands. The two new bands cover (1) the shorter wavelength blue part of the spectrum to help with coastal studies and aerosol analyses/atmospheric correction and (2) an atmospheric water absorption band, where the Earth surface is generally not visible, but Cirrus clouds are, to aid in cloud detection and screening. The radiometry of OLI benefits from improved SNR, dynamic range and quantization. OLI is undergoing system testing with a delivery scheduled for Spring 2011. The TIRS is also a pushbroom design and used QWIPS detectors that require cooling to 43K using a cryocooler. It.has two spectral bands, effectively splitting the ETM+ band 6 in half, that can be used as a split window to aid in atmospheric correction. It has nominally 100 m spatial resolution as opposed to the 60 m of Landsat-7 ETM+: TIRS has commenced integration and test, with a delivery to the spacecraft vendor scheduled for Winter 2011-2012. The Orbital spacecraft currently being integrated for LDCM will have improved capabilities for pointing over previous missions. These capabilities will allow the OLI and TIRS instruments to point off-nadir the equivalent of one WRS-2 path to increase the chances of coverage for high priority targets, particularly in the event of natural disasters. Also, the pointing capability will allow the calibration of the OLI using the sun (roughly weekly), the moon (monthly), stars (during commissioning) and the Earth (at 90 deg from normal orientation, a.k.a., side slither) quarterly. The solar calibration will be used for OLI absolute and relative calibration, the moon for trending the stability of the OLI response, the stars will be used for Line of Sight determination and the side slither will be an alternate OLI and relative gain determination methodology. The spacecraft is scheduled to begin integration with the OLI instrument in Summer 2011. The LDCM data processing and archive system (DPAS), located at USGS EROS, generates the products for distribution to users. Like Landsat-7 this includes an image assessment system for characrizing instrument performance and updating calibration parameters. Products will be generated tha

Markham, Brian; Irons, James; Dabney, Philip

2011-01-01

61

The Next Landsat Satellite: The Landsat Data Continuity Mission  

NASA Technical Reports Server (NTRS)

The Landsat program is one of the longest running satellite programs for Earth observations from space. The program was initiated by the launch of Landsat 1 in 1972. Since then a series of six more Landsat satellites were launched and at least one of those satellites has been in operations at all times to continuously collect images of the global land surface. The Department of Interior (DOI) U.S. Geological Survey (USGS) preserves data collected by all of the Landsat satellites at their Earth Resources Observation and Science (EROS) Center in Sioux Falls, South Dakota. This 40-year data archive provides an unmatched record of the Earth's land surface that has undergone dramatic changes in recent decades due to the increasing pressure of a growing population and advancing technologies. EROS provides the ability for anyone to search the archive and order digital Landsat images over the internet for free. The Landsat data are a public resource for observing, characterizing, monitoring, trending, and predicting land use change over time providing an invaluable tool for those addressing the profound consequences of those changes to society. The most recent launch of a Landsat satellite occurred in 1999 when Landsat 7 was placed in orbit. While Landsat 7 remains in operation, the National Aeronautics and Space Administration (NASA) and the DOI/ USGS are building its successor satellite system currently called the Landsat Data Continuity Mission (LDCM). NASA has the lead for building and launching the satellite that will carry two Earth-viewing instruments, the Operational Land Imager (OLI) and the Thermal Infrared Sensor (TIRS). The OLI will take images that measure the amount of sunlight reflected by the land surface at nine wavelengths of light with three of those wavelengths beyond the range of human vision. T1RS will collect coincident images that measure light emitted by the land surface as a function of surface temperature at two longer wavelengths well beyond the range of human vision. The DOI/USGS is developing the ground system that will command and control the LDCM satellite in orbit and manage the OLI and TIRS data transmitted by the satellite. DOI/USGS will thus operate the satellite and collect, archive, and distribute the image data as part of the EROS archive. DOI/USGS has committed to renaming LDCM as Landsat 8 following launch. By either name the satellite and its sensors will extend the 40-year archive with images sufficiently consistent with data from earlier Landsat satellites to allow multi-decadal, broad-area studies of our dynamic landscapes. The next Landsat satellite and ground system are on schedule for a January, 2013 launch.

Rons, James R.; Dwyer, John L.; Barsi, Julia A.

2012-01-01

62

Overcast: Reliable Multicasting with an Overlay Network  

Microsoft Academic Search

Overcast is an application-level multicasting system that can be incrementally deployed using today's Internet infrastructure. These properties stem from Overcast's implementation as an overlay network. An overlay network consists of a collection of nodes placed at strategic locations in an existing network fabric. These nodes implement a network abstrac- tion on top of the network provided by the under- lying

John Jannotti; David K. Gifford; Kirk L. Johnson; M. Frans Kaashoek; James W. O'Toole Jr.

2000-01-01

63

Censorship resistant overlay publishing Technical Report  

E-print Network

storage systems to resist state-level Internet censorship, construct a system that fulfills thoseCensorship resistant overlay publishing Technical Report Department of Computer Science-027 Censorship resistant overlay publishing Eugene Y. Vasserman, Victor Heorhiadi, Yongdae Kim, and Nicholas J

Minnesota, University of

64

SPINAT: Integrating IPsec into Overlay Routing  

Microsoft Academic Search

Tackling the major Internet security, scalability and mobility problems without essentially changing the existing Internet architecture has turned out to be a very challenging task. The overlay routing approaches fortunately seem to offer a sound way to mitigate most of these issues. Basically, they decouple the end-point identifiers from locators by defining a new namespace. Overlay routing is based on

Jukka Ylitalo; Patrik Salmela; Hannes Tschofenig

2005-01-01

65

CFDP for Interplanetary Overlay Network  

NASA Technical Reports Server (NTRS)

The CCSDS (Consultative Committee for Space Data Systems) File Delivery Protocol for Interplanetary Overlay Network (CFDP-ION) is an implementation of CFDP that uses IO' s DTN (delay tolerant networking) implementation as its UT (unit-data transfer) layer. Because the DTN protocols effect automatic, reliable transmission via multiple relays, CFDP-ION need only satisfy the requirements for Class 1 ("unacknowledged") CFDP. This keeps the implementation small, but without loss of capability. This innovation minimizes processing resources by using zero-copy objects for file data transmission. It runs without modification in VxWorks, Linux, Solaris, and OS/X. As such, this innovation can be used without modification in both flight and ground systems. Integration with DTN enables the CFDP implementation itself to be very simple; therefore, very small. Use of ION infrastructure minimizes consumption of storage and processing resources while maximizing safety.

Burleigh, Scott C.

2011-01-01

66

LANDSAT (MSS): Image demographic estimations  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. Two sets of urban test sites, one with 35 cities and one with 70 cities, were selected in the State, Sao Paulo. A high degree of colinearity (0.96) was found between urban and areal measurements taken from aerial photographs and LANDSAT MSS imagery. High coefficients were observed when census data were regressed against aerial information (0.95) and LANDSAT data (0.92). The validity of population estimations was tested by regressing three urban variables, against three classes of cities. Results supported the effectiveness of LANDSAT to estimate large city populations with diminishing effectiveness as urban areas decrease in size.

Dejesusparada, N. (principal investigator); Foresti, C.

1977-01-01

67

Landsat features for agricultural applications  

NASA Technical Reports Server (NTRS)

This paper presents relationships among Landsat MSS bands and selected transformations of them, with emphasis on the Tasseled-Cap Transformation and its Brightness, Greenness variables. It also discusses relationships between reflectance measurements made in the Landsat spectral bands and actual Landsat data. Agronomically oriented analyses of reflectance measurements of wheat throughout a growing season are presented, with a comparison of various green measures, correlation with crop development stage, and examination of the effects of moisture stress. The final example addresses the use of transformed variables in a newly developed approach to forestry change detection.

Malila, W. A.; Lambeck, P. F.; Crist, E. P.; Jackson, R. D.; Pinter, P. J., Jr.

1980-01-01

68

LANDSAT-4 image data quality analysis. [LANDSAT 5 imagery  

NASA Technical Reports Server (NTRS)

Reformatting software to handle LANDSAT 5 data in quadrant format was completed and tested. The sensor two-dimensional point spread function was estimated from scene data. Budget recalculations are discussed. Two publications done under this contract are named.

Anuta, P. E. (principal investigator)

1984-01-01

69

NASA Scientific Visualization Studio: Landsat  

NSDL National Science Digital Library

This collection of visualizations was made from Landsat imagery. Many of these visualizations are designed to show changes in our environment through time. Subjects include glacial retreat, urban growth, landforms and coastlines, floods, fires, deforestation, volcanism, and others.

70

25 Years of Landsat 5  

NASA Video Gallery

Twenty-two years beyond its primary mission lifetime, Landsat 5 is still going strong. It has charted urban growth in Las Vegas, monitored fire scars in Yellowstone National Park, and tracked the r...

71

Interacting epidemics on overlay networks  

NASA Astrophysics Data System (ADS)

The interaction between multiple pathogens spreading on networks connecting a given set of nodes presents an ongoing theoretical challenge. Here, we aim to understand such interactions by studying bond percolation of two different processes on overlay networks of arbitrary joint degree distribution. We find that an outbreak of a first pathogen providing immunity to another one spreading subsequently on a second network connecting the same set of nodes does so most effectively if the degrees on the two networks are positively correlated. In that case, the protection is stronger the more heterogeneous the degree distributions of the two networks are. If, on the other hand, the degrees are uncorrelated or negatively correlated, increasing heterogeneity reduces the potential of the first process to prevent the second one from reaching epidemic proportions. We generalize these results to cases where the edges of the two networks overlap to arbitrary amount, or where the immunity granted is only partial. If both processes grant immunity to each other, we find a wide range of possible situations of coexistence or mutual exclusion, depending on the joint degree distribution of the underlying networks and the amount of immunity granted mutually. These results generalize the concept of a coexistence threshold and illustrate the impact of large-scale network structure on the interaction between multiple spreading agents.

Funk, Sebastian; Jansen, Vincent A. A.

2010-03-01

72

LANDSAT-D Mission Operations Review (MOR)  

NASA Technical Reports Server (NTRS)

The integrated LANDSAT-D systems operation plan is presented and discussed with respect to functional elements, personnel, and procedures. Specifically, a review of the LANDSAT-D program, mission requirements and management, and flight operations is given.

1982-01-01

73

LANDSAT-5 orbit adjust maneuver report  

NASA Technical Reports Server (NTRS)

The orbit adjust maneuvers performed to raise the LANDSAT 5 spacecraft to mission altitude, synchronize it with the required groundtrack, and properly phase the spacecraft with LANDSAT-4 to provide an 8 day full Earth coverage cycle are described. Maneuver planning and evaluation procedures, data and analysis results for all maneuvers performed to date, the frozen orbit concept, and the phasing requirement between LANDSAT-4 and LANDSAT-5 are also examined.

Hassett, P. J.; Johnson, R. L.

1984-01-01

74

Wheat yield forecasts using Landsat data  

NASA Technical Reports Server (NTRS)

Leaf area index and percentage of vegetative cover, two indices of crop yield developed from Landsat multispectral scanning data, are discussed. Studies demonstrate that the Landsat indicators may be as highly correlated with winter wheat yield as estimates based on traditional field sampling methods; in addition, the Landsat indicators may account for variations in individual field yield which are not explainable by meteorological data. A simple technique employing early-season Landsat data to make wheat yield predictions is also considered.

Colwell, J. E.; Rice, D. P.; Nalepka, R. F.

1977-01-01

75

Solidification of an alloy 625 weld overlay  

NASA Astrophysics Data System (ADS)

The solidification behavior (microsegregation, secondary phase formation, and solidification temperature range) of an Alloy 625 weld overlay deposited on 2.25Cr - 1Mo steel by gas metal arc welding was investigated by light and electron optical microscopy, electron microprobe, and differential thermal analysis techniques. The overlay deposit was found to terminate solidification at ? 1216 °C by a ?/Laves eutectic-type reaction. The Laves phase was highly enriched in Nb, Mo, and Si. The solidification reaction and microsegregation potential of major alloying elements in the overlay deposit are compared to other Nb-bearing Ni base alloys and found to be very similar to those for Alloy 718. Solidification cracks observed in the overlay were attributed to the wide solidification temperature range (?170 °C) and formation of interdendritic ( ?+Laves) constituent. Reasonable agreement is obtained between the calculated and measured volume percent ( ?+Laves) constituent with the Scheil equation by treating the overlay system as a simple ?-Nb “binary” and using an experimentally determined k Nb value from electron microprobe data.

Dupont, J. N.

1996-11-01

76

Robotic weld overlay coatings for erosion control  

SciTech Connect

The erosion of materials by the impact of solid particles has received increasing attention during the past twenty years. Recently, research has been initiated with the event of advanced coal conversion processes in which erosion plays an important role. The resulting damage, termed Solid Particle Erosion (SPE), is of concern primarily because of the significantly increased operating costs which result in material failures. Reduced power plant efficiency due to solid particle erosion of boiler tubes and waterfalls has led to various methods to combat SPE. One method is to apply coatings to the components subjected to erosive environments. Protective weld overlay coatings are particularly advantageous in terms of coating quality. The weld overlay coatings are essentially immune to spallation due to a strong metallurgical bond with the substrate material. By using powder mixtures, multiple alloys can be mixed in order to achieve the best performance in an erosive environment. However, a review of the literature revealed a lack of information on weld overlay coating performance in erosive environments which makes the selection of weld overlay alloys a difficult task. The objective of this project is to determine the effects of weld overlay coating composition and microstructure on erosion resistance. These results will lead to a better understanding of erosion mitigation in CFB`s.

Not Available

1994-11-01

77

Robotic weld overlay coatings for erosion control  

NASA Astrophysics Data System (ADS)

The erosion of materials by the impact of solid particles has received increasing attention during the past twenty years. Recently, research has been initiated with the event of advanced coal conversion processes in which erosion plays an important role. The resulting damage, termed Solid Particle Erosion (SPE), is of concern primarily because of the significantly increased operating costs which result in material failures. Reduced power plant efficiency due to solid particle erosion of boiler tubes and waterfalls has led to various methods to combat SPE. One method is to apply coatings to the components subjected to erosive environments. Protective weld overlay coatings are particularly advantageous in terms of coating quality. The weld overlay coatings are essentially immune to spallation due to a strong metallurgical bond with the substrate material. By using powder mixtures, multiple alloys can be mixed in order to achieve the best performance in an erosive environment. However, a review of the literature revealed a lack of information on weld overlay coating performance in erosive environments which makes the selection of weld overlay alloys a difficult task. The objective of this project is to determine the effects of weld overlay coating composition and microstructure on erosion resistance. These results will lead to a better understanding of erosion mitigation in CFB's.

78

Solidification of an alloy 625 weld overlay  

SciTech Connect

The solidification behavior (microsegregation, secondary phase formation, and solidification temperature range) of an Alloy 625 weld overlay deposited on 2.25Cr-1Mo steel by gas metal arc welding was investigated by light and electron optical microscopy, electron microprobe, and differential thermal analysis techniques. The overlay deposit was found to terminate solidification at {approx}1,216 C by a {gamma}/Laves eutectic-type reaction. The Laves phase was highly enriched in Nb, Mo, and Si. The solidification reaction and microsegregation potential of major alloying elements in the overlay deposit are compared to other Nb-bearing Ni base alloys and found to be very similar to those for Alloy 718. Solidification cracks observed in the overlay were attributed to the wide solidification temperature range ({approx}170 C) and formation of interdendritic ({gamma} + Laves) constituent. Reasonable agreement is obtained between the calculated and measured volume percent ({gamma} + Laves) constituent with the Scheil equation by treating the overlay system as a simple {gamma}-Nb binary and using an experimentally determined k{sub Nb} value from electron microprobe data.

DuPont, J.N. [Lehigh Univ., Bethlehem, PA (United States). Energy Research Center

1996-11-01

79

The Landsat-D Assessment System  

NASA Technical Reports Server (NTRS)

The overall Landsat-D system is discussed with emphasis on the objectives, configuration, and capabilities of the Landsat-D Assessment System. This system is being developed to support investigations which demonstrate, evaluate, and assess the utility of Landsat-D data for a wide variety of earth observations applications.

Bracken, P. A.; Billingsley, J. B.; Lynch, T. J.; Quann, J. J.

1979-01-01

80

Adaptive processing for LANDSAT data  

NASA Technical Reports Server (NTRS)

Analytical and test results on the use of adaptive processing on LANDSAT data are presented. The Kalman filter was used as a framework to contain different adapting techniques. When LANDSAT MSS data were used all of the modifications made to the Kalman filter performed the functions for which they were designed. It was found that adaptive processing could provide compensation for incorrect signature means, within limits. However, if the data were such that poor classification accuracy would be obtained when the correct means were used, then adaptive processing would not improve the accuracy and might well lower it even further.

Crane, R. B.; Reyer, J. F.

1975-01-01

81

An operational application of satellite snow cover observations, northwest United States. [using LANDSAT 1  

NASA Technical Reports Server (NTRS)

LANDSAT-1 imagery showing extent of snow cover was collected and is examined for the 1973 and 1974 snowmelt seasons for three Columbia River Basins. Snowlines were mapped and the aerial snow cover was determined using satellite data. Satellite snow mapping products were compared products from conventional information sources (computer programming and aerial photography was used). Available satellite data were successfully analyzed by radiance thresholding to determine snowlines and the attendant snow-covered area. Basin outline masks, contour elevation masks, and grid overlays were utilized as satellite data interpretation aids. Verification of the LANDSAT-1 data was generally good although there were exceptions. A major problem was lack of adequate cloud-free satellite imagery of high resolution and determining snowlines in forested areas.

Dillard, J. P.

1975-01-01

82

Next Generation Landsat Products Delivered Using Virtual Globes and OGC Standard Services  

NASA Astrophysics Data System (ADS)

The Landsat Data Continuity Mission (LDCM) is the next in the series of Landsat satellite missions and is tasked with the objective of delivering data acquired by the Operational Land Imager (OLI). The OLI instrument will provide data continuity to over 30 years of global multispectral data collected by the Landsat series of satellites. The U.S. Geological Survey Earth Resources Observation and Science (USGS EROS) Center has responsibility for the development and operation of the LDCM ground system. One of the mission objectives of the LDCM is to distribute OLI data products electronically over the Internet to the general public on a nondiscriminatory basis and at no cost. To ensure the user community and general public can easily access LDCM data from multiple clients, the User Portal Element (UPE) of the LDCM ground system will use OGC standards and services such as Keyhole Markup Language (KML), Web Map Service (WMS), Web Coverage Service (WCS), and Geographic encoding of Really Simple Syndication (GeoRSS) feeds for both access to and delivery of LDCM products. The USGS has developed and tested the capabilities of several successful UPE prototypes for delivery of Landsat metadata, full resolution browse, and orthorectified (L1T) products from clients such as Google Earth, Google Maps, ESRI ArcGIS Explorer, and Microsoft's Virtual Earth. Prototyping efforts included the following services: using virtual globes to search the historical Landsat archive by dynamic generation of KML; notification of and access to new Landsat acquisitions and L1T downloads from GeoRSS feeds; Google indexing of KML files containing links to full resolution browse and data downloads; WMS delivery of reduced resolution browse, full resolution browse, and cloud mask overlays; and custom data downloads using WCS clients. These various prototypes will be demonstrated and LDCM service implementation plans will be discussed during this session.

Neiers, M.; Dwyer, J.; Neiers, S.

2008-12-01

83

Patent Overlay Mapping: Visualizing Technological Distance  

E-print Network

The purpose of this paper is to present a new global patent map that represents all technological categories, and a method to locate patent data of individual organizations and technological fields on the global map. This second patent overlay map technique is shown to be of potential interest to support competitive intelligence and policy decision-making. The global patent map is based on similarities in citing-to-cited relationships between categories of the International Patent Classification (IPC) of European Patent Office (EPO) patents from 2000 to 2006. This patent dataset, extracted from PatStat database, represents more than 760,000 patent records in more than 400 IPC categories. To illustrate the kind of analytical support offered by this approach, the paper shows the overlay of nanotechnology-related patenting activities of two companies and two different nanotechnology subfields on to the global patent map. The exercise shows the potential of patent overlay maps to visualize technological areas and...

Kay, Luciano; Youtie, Jan; Porter, Alan L; Rafols, Ismael

2012-01-01

84

Weld overlay coatings for erosion control  

SciTech Connect

A literature review was made. In spite of similarities between abrasive wear and solid particle erosion, weld overlay hardfacing alloys that exhibit high abrasion resistance may not necessarily have good erosion resistance. The performance of weld overlay hardfacing alloys in erosive environments has not been studied in detail. It is believed that primary-solidified hard phases such as carbides and intermetallic compounds have a strong influence on erosion resistance of weld overlay hardfacing alloys. However, relationships between size, shape, and volume fraction of hard phases in a hardfacing alloys and erosion resistance were not established. Almost all hardfacing alloys can be separated into two major groups based upon chemical compositions of the primary solidified hard phases: (a) carbide hardening alloys (Co-base/carbide, WC-Co and some Fe base superalloys); and (b) intermetallic hardening alloys (Ni-base alloys, austenitic steels, iron-aluminides).

Levin, B.; DuPont, J.N.; Marder, A.R.

1993-03-03

85

Robotic weld overlay coatings for erosion control  

SciTech Connect

Twelve weld overlay hardfacing alloys have been selected for preliminary erosion testing based on a literature review These alloys have been separated into three major groups: (1) Cobalt containing alloys, (2) Nickel-base alloys, (3) Iron base alloys. These alloys are being applied to carbon steel substrates and will undergo preliminary erosion testing to identify candidates weld overlay alloys for erosion control in CFB boilers. The candidate alloys selected from the preliminary erosion tests will then undergo more detailed evaluations in future research.

Levin, B.F.; Dupont, J.N.; Marder, A.R.

1993-04-18

86

Landsat 7 Science Data Processing: An Overview  

NASA Technical Reports Server (NTRS)

The Landsat 7 Science Data Processing System, developed by NASA for the Landsat 7 Project, provides the science data handling infrastructure used at the Earth Resources Observation Systems (EROS) Data Center (EDC) Landsat Data Handling Facility (DHF) of the United States Department of Interior, United States Geological Survey (USGS) located in Sioux Falls, South Dakota. This paper presents an overview of the Landsat 7 Science Data Processing System and details of the design, architecture, concept of operation, and management aspects of systems used in the processing of the Landsat 7 Science Data.

Schweiss, Robert J.; Daniel, Nathaniel E.; Derrick, Deborah K.

2000-01-01

87

LANDSAT-D Investigations Workshop  

NASA Technical Reports Server (NTRS)

The objectives and methods used to determine the performance of the LANDSAT-D thematic mapper radiometric and geometric sensors are depicted in graphs and charts. Other aspects illustrated include ground and flight segment TM geometric processing and early access TM processing.

1982-01-01

88

LANDSAT-1 flight evaluation report  

NASA Technical Reports Server (NTRS)

Flight performance analysis for the tenth quarter of operation orbit 11467 to 12745 of LANDSAT 1 are presented. Payload subsystems discussed include: power subsystem; attitude control subsystem; telemetry subsystem; electrical interface subsystem; narrowband tape recorders; wideband telemetry subsystem; return beam vidicon subsystem; multispectral scanner subsystem; and data collection system.

1975-01-01

89

Landsat and Thermal Infrared Imaging  

NASA Technical Reports Server (NTRS)

The purpose of this chapter is to describe the collection of thermal images by Landsat sensors already on orbit and to introduce the new thermal sensor to be launched in 2013. The chapter describes the thematic mapper (TM) and enhanced thematic mapper plus (ETM+) sensors, the calibration of their thermal bands, and the design and prelaunch calibration of the new thermal infrared sensor (TIRS).

Arvidson, Terry; Barsi, Julia; Jhabvala, Murzy; Reuter, Dennis

2012-01-01

90

Continuity of Landsat observations: Short term considerations  

USGS Publications Warehouse

As of writing in mid-2010, both Landsat-5 and -7 continue to function, with sufficient fuel to enable data collection until the launch of the Landsat Data Continuity Mission (LDCM) scheduled for December of 2012. Failure of one or both of Landsat-5 or -7 may result in a lack of Landsat data for a period of time until the 2012 launch. Although the potential risk of a component failure increases the longer the sensor's design life is exceeded, the possible gap in Landsat data acquisition is reduced with each passing day and the risk of Landsat imagery being unavailable diminishes for all except a handful of applications that are particularly data demanding. Advances in Landsat data compositing and fusion are providing opportunities to address issues associated with Landsat-7 SLC-off imagery and to mitigate a potential acquisition gap through the integration of imagery from different sensors. The latter will likely also provide short-term, regional solutions to application-specific needs for the continuity of Landsat-like observations. Our goal in this communication is not to minimize the community's concerns regarding a gap in Landsat observations, but rather to clarify how the current situation has evolved and provide an up-to-date understanding of the circumstances, implications, and mitigation options related to a potential gap in the Landsat data record. ?? 2010.

Wulder, M.A.; White, J.C.; Masek, J.G.; Dwyer, J.; Roy, D.P.

2011-01-01

91

Addressing the P2P Bootstrap Problem for Small Overlay Networks  

E-print Network

presenting a survey of various public overlays, we identify two overlays that match the requirements: XMPP-scale private structured overlays from public Brunet or XMPP infrastructures. I. INTRODUCTION While P2P overlays

Figueiredo, Renato J.

92

Robotic weld overlay coatings for erosion control  

NASA Astrophysics Data System (ADS)

Research is being conducted to develop criteria for selecting weld overlay coatings for erosion mitigation in circulated fluidized beds. Twelve weld overlay alloys were deposited on 1018 steel substrates using plasma arc welding. Ten samples from each coating were prepared for erosion testing. All selected coatings were erosion tested at 400C and their erosion resistance and microstructure evaluated. Steady state erosion rates were similar for several weld overlay coatings (Ultimet, Inconel-625, Iron-Aluminide, 316L SS, and High Chromium Cast Iron) and were considerably lower than the remaining coating evaluated. These coatings had different base (Co, Fe, Ni-base). No correlations were found between room temperature microhardness of the weld overlay coatings and their erosion resistance at elevated temperature, although this criteria is often thought to be an indicator of erosion resistance. It was suggested that the coatings that showed similar erosion rates may have similar mechanical properties such as fracture strength, toughness and work hardening rates at this temperature. During the past quarter, Iron-Aluminide, Inconel-625, and 316L SS coatings were selected for more detailed investigations based upon the preliminary erosion test results. Microhardness tests were performed on eroded samples to determine the size of the work hardened zone and change in coatings hardness due to erosion. The work hardened zone was correlated with erosion resistance of the coatings. Additional Iron-Aluminide, Inconel-625, and 316L SS coatings were deposited on 1018 steel substrates.

Levin, B. F.; Dupont, J. N.; Marder, A. R.

1994-01-01

93

Summary of Concrete Overlays Existing concrete pavement  

E-print Network

Summary of Concrete Overlays Existing concrete pavement with surface distresses Prepared surface Monolithic pavement with new concrete surface Existing asphalt pavement with surface distresses Milled pavement with asphalt surface distresses Milled and cleaned surface New 2­5 in. (5.1­12.7 cm) bonded

94

Impact of chuck flatness on wafer distortion and stepper overlay  

Microsoft Academic Search

Overlay accuracy is known as one of the most important subjects for ULSI device production. Significant contributions such as alignment accuracy and mask distortions are well known. By breaking the 100 nm range on overlay accuracy a number of influences have to take into account, which were usually neglected for relaxed design rules. One of these influences to the overlay

Klaus Simon; H.-U. Scheunemann; Hans L. Huber; F. Gabeli

1993-01-01

95

LANDSAT-1 and LANDSAT-2 flight evaluation report  

NASA Technical Reports Server (NTRS)

The LANDSAT-1 spacecraft was launched from the Western Test Range on 23 July 1972, at 18:08:06.508Z. The launch and orbital injection phase of the space flight was nominal and deployment of the spacecraft followed predictions. Orbital operations of the spacecraft and payload subsystems were satisfactory through Orbit 147, after which an internal short circuit disabled one of the Wideband Video Tape Recorders (WBVTR-2). Operations resumed until Orbit 196, when the Return Beam Vidicon failed to respond when commanded off. The RBV was commanded off via alternate commands. LANDSAT-1 continued to perform its imaging mission with the Multispectral Scanner and the remaining Wideband Video Tape Recorder providing image data.

1976-01-01

96

Landsat, computers, and development projects.  

PubMed

Data provided by earth-orbiting satellites and analyzed through specific computer techniques are rapidly providing policy-makers around the world with new information on the location and extent of their countries' renewable and nonrenewable resources. Development projects utilizing remote sensing technology are being supported, for example, by the Inter-American Development Bank, the World Bank, and other international funding agencies. The Inter-American Development Bank is financing a natural resources inventory of five countries in Central America, and this will require the application of remote sensing in the analysis of 33 Landsat images covering the area. Although the Landsat program remains experimental in nature, studies pertaining to its follow-on aspects will ensure continuation of the program so that developed and developing countries will be able to maintain better control of the management of their natural resources. PMID:17842110

Adrien, P M; Baumgardner, M F

1977-11-01

97

Landsat-8 data processing evolution  

NASA Astrophysics Data System (ADS)

Shortly after Landsat-8 launched in February 2013, the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center began creating radiometrically and geometrically corrected products. In order to provide these products as soon as possible, the Landsat Product Generation System (LPGS) was developed based on instrument designs and testing prior to launch. While every effort was made to ensure the LPGS produces highly accurate products, some aspects of the sensors are difficult to characterize during testing on the ground. Examples of these characteristics include differences between individual detectors that make up the focal plane array, and the way detectors view radiometric targets in preflight testing versus the way they view the Earth on orbit, and the accuracy of the measurements made on the ground. Once in orbit, more accurate measurements of these sensor characteristics were made that improved processing parameters, resulting in improved quality of the final imagery. This paper reviews the changes that have occurred to the processing of Landsat-8 data products which include parameter changes as well as some modifications to the processing system itself. These changes include: improved linearization of the data, both to parameters and the algorithm used for linearizing the data; improved radiance and reflectance conversion coefficients; individual detector coefficients to improve uniformity; and geometric alignment coefficients to improve the geometric accuracy. These improvements lead to a reprocessing campaign that occurred in early in 2014 that replaced all prior data with improved products.

Morfitt, Ron A.; Choate, Mike J.; Barsi, Julia A.

2014-10-01

98

How big does a coloured overlay have to be?  

PubMed

Coloured overlays and coloured lenses can both increase reading speed, but when they do their colour is not necessarily the same, suggesting that the beneficial effects of a coloured filter might depend upon the area of the visual field that it colours. We investigated the effects of overlays on reading speed and varied the size of the overlay and the colour of the surround. Children who had been assessed with coloured overlays were required to read a passage of randomly ordered common words. The words were printed in black ink as a block of text positioned centrally on an A4 page of white paper in landscape orientation. The speed of reading was compared under four conditions: (1) without an overlay; (2) with an overlay of the chosen colour covering the entire page; (3) with the overlay cut so that it just covered the text but left the margin white; (4) with the overlay of the chosen colour covering the text but with the margin coloured a complementary colour, using a second overlay. The children who were using an overlay read more quickly with the overlay; those who were no longer using the overlay did not. Although the block of text covered less than half the page, the colour and nature of the margin did not affect reading speed significantly. These findings suggest that in order to be effective at improving reading speed an overlay needs to cover the text, but not necessarily the remainder of the page, which means that smaller overlays may sometimes be sufficient. PMID:14687202

Waldie, Michelle; Wilkins, Arnold

2004-01-01

99

Landsat: Making a Difference, One User at a Time  

NASA Video Gallery

The Landsat Data Continuity Mission will continue and improve upon the 40-year-old Landsat program. This video examines two uses of Landsat data to monitor agriculture. Both wineries and timber com...

100

Acquisition and preprocessing of LANDSAT data  

NASA Technical Reports Server (NTRS)

The original configuration of the GSFC data acquisition, preprocessing, and transmission subsystem, designed to provide LANDSAT data inputs to the LACIE system at JSC, is described. Enhancements made to support LANDSAT -2, and modifications for LANDSAT -3 are discussed. Registration performance throughout the 3 year period of LACIE operations satisfied the 1 pixel root-mean-square requirements established in 1974, with more than two of every three attempts at data registration proving successful, notwithstanding cosmetic faults or content inadequacies to which the process is inherently susceptible. The cloud/snow rejection rate experienced throughout the last 3 years has approached 50%, as expected in most LANDSAT data use situations.

Horn, T. N.; Brown, L. E.; Anonsen, W. H. (principal investigators)

1979-01-01

101

Overlay Tolerances For VLSI Using Wafer Steppers  

NASA Astrophysics Data System (ADS)

In order for VLSI circuits to function properly, the masking layers used in the fabrication of those devices must overlay each other to within the manufacturing tolerance incorporated in the circuit design. The capabilities of the alignment tools used in the masking process determine the overlay tolerances to which circuits can be designed. It is therefore of considerable importance that these capabilities be well characterized. Underestimation of the overlay accuracy results in unnecessarily large devices, resulting in poor utilization of wafer area and possible degradation of device performance. Overestimation will result in significant yield loss because of the failure to conform to the tolerances of the design rules. The proper methodology for determining the overlay capabilities of wafer steppers, the most commonly used alignment tool for the production of VLSI circuits, is the subject of this paper. Because cost-effective manufacturing process technology has been the driving force of VLSI, the impact on productivity is a primary consideration in all discussions. Manufacturers of alignment tools advertise the capabilities of their equipment. It is notable that no manufacturer currently characterizes his aligners in a manner consistent with the requirements of producing very large integrated circuits, as will be discussed. This has resulted in the situation in which the evaluation and comparison of the capabilities of alignment tools require the attention of a lithography specialist. Unfortunately, lithographic capabilities must be known by many other people, particularly the circuit designers and the managers responsible for the financial consequences of the high prices of modern alignment tools. All too frequently, the designer or manager is confronted with contradictory data, one set coming from his lithography specialist, and the other coming from a sales representative of an equipment manufacturer. Since the latter generally attempts to make his merchandise appear as attractive as possible, the lithographer is frequently placed in the position of having to explain subtle issues in order to justify his decisions. It is the purpose of this paper to provide that explanation.

Levinson, Harry J.; Rice, Rory

1988-01-01

102

Investigation of dielectric overlay microstrip circuits  

E-print Network

capacitance. The advantage of this method is that it provides a closed-form solution. However, this method in its current form is limited to a specific structure containing four dielectric layers. The second method that is well suited to the overlay... capacitances. The first is the capacitance of the structure with all dielectrics replaced by air, this is denoted by C . The second capacitance is that where the dielectrics are present, denoted by C. From these two capacitances, the characteristic impedance...

Klein, James Louis

2012-06-07

103

Scalability of Reliable Group Communication Using Overlays  

Microsoft Academic Search

This study provides some new insights into the scalability of reliable group communication mechanisms using overlays. These mechanisms use individual TCP connections for packet transfers between end-systems. End-systems store incoming packets and forward them to downstream nodes using different unicast TCP connections. In this paper we assume that buffers in end-systems are large enough for the transfers. It is shown

François Baccelli; Augustin Chaintreau; Zhen Liu; Anton Riabov; Sambit Sahu

2004-01-01

104

Rewiring strategies for semantic overlay networks  

Microsoft Academic Search

Semantic overlay networks cluster peers that are semantically, thematically or socially close into groups, by means of a rewiring\\u000a procedure that is periodically executed by each peer. This procedure establishes new connections to similar peers and disregards\\u000a connections to peers that are dissimilar. Retrieval effectiveness is then improved by exploiting this information at query\\u000a time (as queries may address clusters

Paraskevi Raftopoulou; Euripides G. M. Petrakis; Christos Tryfonopoulos

2009-01-01

105

Characteristics of the Landsat Multispectral Data System  

USGS Publications Warehouse

Landsat satellites were launched into orbit in 1972 and 1975. Additional Landsat satellites are planned for launch in 1978 and 1981. The satellites orbit the Earth at an altitude of approximately 900 km and each can obtain repetitive coverage of cloud-free areas every 18 days. A sun-synchronous orbit is used to insure repeatable illumination conditions. Repetitive satellite coverage allows optimal cover conditions for geologic applications to be identified. Seasonal variations in solar illumination must be analyzed to select the best Landsat data for geologic applications. Landsat data may be viewed in stereo where there is sufficient sidelap and sufficient topographic relief. Landsat-1 ceased operation on January 10, 1978. Landsat-2 detects, only solar radiation that is reflected from the Earth's surface in visible and near-visible wavelengths. The third Landsat will also detect emitted thermal radiation. The multispectral scanner (MSS) was the only sensing instrument used on the first two satellites. The MSS on Landsats-1 and -2 detect radiation which is reflected from a 79 m by 79 m area, and the data are formatted as if the measurement was made from a 56 m by 79 m area. The MSS integrates spectral response from all cover types within the 79 m by 79 m area. The integrated spectral signature often does not resemble the spectral signature from individual cover types, and the integrated signature is also modified by the atmosphere. Landsat-1 and -2 data are converted to 70 mm film and computer compatible tapes (CCT's) at Goddard Space Flight Center (GSFC); these are shipped to the EROS Data Center (EDC) for duplication and distribution to users. Landsat-C data will be converted to 241 mm-wide film and CCT's at EDC. Landsat-D data will be relayed from the satellite directly to geosynchronous satellites and then to the United States from any location on Earth.

Taranik, James V.

1978-01-01

106

Landsat-4 data quality analysis  

NASA Technical Reports Server (NTRS)

Landsat-4 satellite Thematic Mapper (TM) and multispectral scanner (MSS) data have been analyzed in order to ascertain data quality and information content. Geometric evaluations have tested band-to-band registration accuracy, and the TM's overall system resolution was evaluated for the case of image objects with high contrast, sharp edge responses. The information content evaluation employed clustering, principal components, and the transformed divergence separability measured on data from Iowa and Chicago, Illinois. The MSS classification analysis compared MSS and TM information contents for a large number of science classes.

Anuta, P.; Bartolucci, L.; Dean, E.; Lozano, F.; Malaret, E.; Mcgillem, C.; Valdes, J.; Valenzuela, C.

1984-01-01

107

Investigations using data from LANDSAT-2  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. New lands for forestation were set aside in the coastal area of Bangladesh, based on LANDSAT mosaics (Chittagong - 195,000 acres, Noakhali - 450,000 acres, Barisal - 360,000 acres, and Patuakhali - 225,000 acres). LANDSAT imageries were used for identification of drainage patterns in both the old and and new Comilla district.

Hossain, A. (principal investigator)

1977-01-01

108

Global Web-Enabled Landsat Data (Invited)  

NASA Astrophysics Data System (ADS)

The 40+ year series of Landsat satellites provides the longest temporal record of space-based observations acquired with spatial resolutions appropriate for monitoring anthropogenic change. The need for 'higher-level' Landsat products, i.e., beyond currently available radiometrically and geometrically corrected Landsat scenes, has been advocated by the user community and by the Landsat science team. The NASA funded Web-enabled Landsat Data (WELD) project has demonstrated this capability by systematically generating 30m weekly, seasonal, monthly and annual composited Landsat mosaics of the conterminous United States (CONUS) and Alaska for 10+ years (http://weld.cr.usgs.gov/). Recently, the WELD code has been ported to the NASA Earth Exchange (NEX) high performance super computing and data platform to generate global 30m WELD products from contemporaneous Landsat 5 and 7 data. The WELD products and select applications that take advantage of the consistently processed WELD time series are showcased. Prototype global monthly 30m products and plans to expand the production to provide Landsat 30m higher level products for any terrestrial non-Antarctic location for six 3-year epochs from 1985 to 2010 are presented. Prototype monthly global NEX 30m WELD product

Roy, D. P.; Kovalskyy, V.; Kommareddy, I.; Votava, P.; Nemani, R. R.; Egorov, A.; Hansen, M.; Yan, L.

2013-12-01

109

Landsat 7 Fly Over of Tampa, Florida  

NSDL National Science Digital Library

Viewing Earth from space, the Landsat 7 satellite takes images of the Earth, which allows us to look at land changes such as; urban growth, deforestation, and overall changes in the Earth itself. Here is a Landsat 7 image of Tampa, Florida

Snodgrass, Stuart; Williams, Darrel

2000-01-01

110

Landsat 7: Remote Sensing Environmental Problems  

NSDL National Science Digital Library

This educational brief presents a discussion of how the Landsat project has been able to provide data on environmental changes and potential problems. Topics include a short history of the project, an overview of the sorts of environmental issues Landsat satellites are able to "see" from space, and a brief description of ground truthing and how it supports remotely sensed data.

111

LANDSAT 1 US cumulative catalog, 1975 - 1976  

NASA Technical Reports Server (NTRS)

The LANDSAT 1 U.S. Cumulative Catalog lists U.S. imagery acquired by LANDSAT 1 which has been processed and input to the data files during the referenced year. Data, such as date acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found is also given.

1976-01-01

112

LANDSAT D operations control center study  

NASA Technical Reports Server (NTRS)

Various aspects of the planned LANDSAT D system are discussed. LANDSAT D incorporates the Thematic Mapper (TM) as a sensor, it utilizes the Multi-mission Modular Spacecraft (MMS), it makes use of the Tracking and Data Relay Satellite System (TDRSS) and it employs a more advanced ground system. Each of these represent significant improvements in the state-of-the-art.

Alexander, L.; Brown, G.; Clemson, B.; Efner, J.; Engelberg, N.; Owen, J.; Winchester, T.

1977-01-01

113

Highly corrosion resistant weld overlay for oil patch applications  

SciTech Connect

Petroleum equipment companies currently sell 4130 and 4140 steel pipe with alloy 625 (UNS N06625) weld overlay for Oil Patch applications. Alloy 686 (UNS N06686), because of it`s superior corrosion resistance, is currently being evaluated as a replacement material for alloy 625. Mechanical properties and Slow Strain Rate test results for the alloy 686 weld overlay are discussed relative to the alloy 625 weld overlay.

Hibner, E.L. [Inco Alloys International, Inc., Huntington, WV (United States); Maligas, M.N.; Vicic, J.C. [FMC Corp., Houston, TX (United States)

1994-12-31

114

Basic studies of overlay performance on immersion lithography tool  

NASA Astrophysics Data System (ADS)

Immersion lithography with ArF light and Ultra Pure Water (UPW) is the most promising technology for semiconductor manufacturing with 65 nm hp design and below. Since Nikon completed the first full-field immersion scanner, the Engineering Evaluation Tool (EET, NA=0.85) at the end of 2004, Toshiba and Nikon have investigated overlay accuracy with the EET which uses the local fill nozzle. EET successfully demonstrated immersion tools are comparable in single machine overlay accuracy to dry tools, and immersion-dry matching has the same level overlay matching accuracy as dry-dry matching. EET also made it clear that overlay accuracy is independent of scanning speed, and both solvent-soluble topcoats, as well as developer-soluble topcoats can be used without degradation of overlay accuracy. We investigated the impact of the thermal environment on overlay accuracy also, assuming that a key technology of overlay with immersion tools must achieve thermal stabilities similar to dry tools. It was found that the temperature of supply water and loading wafer are stable enough to keep the overlay accuracy good. As for evaporation heat, water droplets on the backside of the wafer lead to overlay degradation. We have decided to equip the wafer holder of S609B, the first immersion production model, with an advanced watertight structure.

Shiraishi, Ken-ichi; Fujiwara, Tomoharu; Tanizaki, Hirokazu; Ishii, Yuuki; Kono, Takuya; Nakagawa, Shinichiro; Higashiki, Tatsuhiko

2006-03-01

115

Overview of the Landsat-7 Mission  

NASA Technical Reports Server (NTRS)

Landsat-7 is scheduled for launch on April 15 from the Western Test Range at Vandenberg Air Force Base, Calif., on a Delta-H expendable launch vehicle. The Landsat 7 satellite consists of a spacecraft bus being provided by Lockheed Martin Missiles and Space (Valley Forge, Pa.) and the Enhanced Thematic Mapper Plus instrument built by Raytheon (formerly Hughes) Santa Barbara Remote Sensing (Santa Barbara, Calif.). The instrument on board Landsat 7 is the Enhanced Thematic Mapper Plus (ETM+). ETM+ improves upon the previous Thematic Mapper (TM) instruments on Landsat's 4 and 5 (Fig. la and lb). It includes the previous 7 spectral bands measuring reflected solar radiation and emitted thermal emissions but, in addition, includes a new 15 in panchromatic (visible-near infrared) band. The spatial resolution of the thermal infrared band has also been improved to 60 m. Both the radiometric precision and accuracy of the sensor are also improved from the previous TM sensors. After being launched into a sun-synchronous polar orbit, the satellite will use on-board propulsion to adjust its orbit to a circular altitude of 438 miles (705 kilometers) crossing the equator at approximately 10 a.m. on its southward track. This orbit will place Landsat 7 along the same ground track as previous Landsat satellites. The orbit will be maintained with periodic adjustments for the life of the mission. A three-axis attitude control subsystem will stabilize the satellite and keep the instrument pointed toward the Earth to within 0.05 degrees. Later this year, plans call for the NASA Earth Observation System (EOS) Terra (AM-1) observatory and the experimental EO-1 mission to closely follow Landsat-7's orbit to support synergistic research and applications from this new suite of terrestrial sensor systems. Landsat is the United States' oldest land-surface observation satellite system, with satellites continuously operating since 1972. Although the program has scored numerous successes in scientific and resource-management applications, Landsat has had a tumultuous history of management and funding changes over its nearly 27-year history. Landsat-7 marks a new direction in the program to reduce the cost of data and increase systematic global coverage for use in global change research as well as commercial and regional applications. With the passage of the Land Remote Sensing Policy Act in 1992, oversight of the Landsat program began to shift from the commercial sector to the federal government. NASA integrated Landsat-7 into its EOS science program in 1994. Landsat-7 is managed and operated jointly by NASA and U.S. Geological Survey (USGS). As a result, the costs of acquiring observations from

Williams, Darrel; Irons, James; Goward, Samuel N.; Masek, Jefery

1999-01-01

116

Investigation of Iron Aluminide Weld Overlays  

SciTech Connect

Conventional fossil fired boilers have been retrofitted with low NO(sub)x burners in order for the power plants to comply with new clean air regulations. Due to the operating characteristics of these burners, boiler tube sulfidation corrosion typically has been enhanced resulting in premature tube failure. To protect the existing panels from accelerated attack, weld overlay coatings are typically being applied. By depositing an alloy that offers better corrosion resistance than the underlying tube material, the wastage rates can be reduced. While Ni-based and stainless steel compositions are presently providing protection, they are expensive and susceptible to failure via corrosion-fatigue due to microsegregation upon solidification. Another material system presently under consideration for use as a coating in the oxidation/sulfidation environments is iron-aluminum. These alloys are relatively inexpensive, exhibit little microsegregation, and show excellent corrosion resistance. However, their use is limited due to weldability issues and their lack of corrosion characterization in simulated low NO(sub)x gas compositions. Therefore a program was initiated in 1996 to evaluate the use of iron-aluminum weld overlay coatings for erosion/corrosion protection of boiler tubes in fossil fired boilers with low NO(sub)x burners. Investigated properties included weldability, corrosion behavior, erosion resistance, and erosion-corrosion performance.

Banovic, S.W.; DuPont, J.B.; Levin, B.F.; Marder, A.R.

1999-08-02

117

Landsat - Current and future capabilities for agriculture  

NASA Technical Reports Server (NTRS)

The potential of the Landsat spacecraft in applications related to agriculture is demonstrated by the examples of assessing the damage to the Brazilian coffee crop due to freezing temperatures on July 17-18, 1975; and damage assessment in the state of Iowa, following a tornado which struck a corn and soybean producing region on June 13, 1976. Some techniques which have been used to measure snow covers on the basis of Landsat data are also noted. The advantages that are expected to accrue from the installation of sophisticated equipment on the third and fourth Landsat spacecraft, scheduled to be launched in 1978 and 1981, respectively, are reviewed.

Walter, L. S.

1977-01-01

118

Landsat/4/Global Positioning System navigation results  

NASA Technical Reports Server (NTRS)

An experimental GPSPAC flown on the Landsat-4 spacecraft was the first spaceborne navigation system to use the NAVSTAR Global Position System (GPS). In order to validate the accuracy and reliability of GPSPAC orbit solutions, definitive Landsat-4 ephemerides, derived from ground based tracking data, were generated and compared with GPSPAC estimates. In addition, Landsat-4 orbital solutions were reconstructed from raw GPS measurement data with a GPSPAC navigation simulator program using different Kalman filter constants. Ephemeris comparisons and simulator results are presented, as well as recommendations for the navigation filter.

Heuberger, H.; Church, L.

1984-01-01

119

Repeated-Game Modeling of Multicast Overlays Mike Afergan  

E-print Network

Repeated-Game Modeling of Multicast Overlays Mike Afergan MIT CSAIL Email: afergan Abstract-- This paper studies multicast application overlay networks in a repeated-game framework introduce a repeated-game model of user behavior that captures the practical tradeoff between a user's short

Chen, Yiling

120

Information Overlay for Camera Phones in Indoor Environments  

E-print Network

,gaetano}@cs.washington.edu Abstract. Increasingly, cell phones are used to browse for information while location systems assist step fur- ther and actually overlay information on to the physical world using the cell phone's cameraInformation Overlay for Camera Phones in Indoor Environments Harlan Hile and Gaetano Borriello Dept

Anderson, Richard

121

Cluster Overlay Broadcast (COB): MANET Routing with Complexity Polynomial in  

E-print Network

Cluster Overlay Broadcast (COB): MANET Routing with Complexity Polynomial in Source and operation of very large scale wireless mobile ad hoc networks (MANETs). In this paper, we develop and analyze Cluster Overlay Broadcast (COB), a low-complexity routing algorithm for MANETs. COB runs on top

Reisslein, Martin

122

DCast: Sustaining Collaboration in Overlay Multicast despite Rational Collusion  

E-print Network

design, incentive mechanism, rational col- lusion, sybil attack, whitewashing attack, overlay multicast 1-1-4503-1651-4/12/10 ...$15.00. streaming of sporting events or TV programs. A peer in over- lay multicast is supposed.1 and PPLive online TV platform [22]) often rely on overlay multicast. To prevent peers from free

Yu, Haifeng

123

Exogenous-Loss Aware Traffic Management in Overlay Networks  

E-print Network

Exogenous-Loss Aware Traffic Management in Overlay Networks Toward Global Fairness Mina Guirguis be taken into account in overlay traffic management techniques that aim to achieve global fairness Traffic Managers (OTMs). We use an equation based approach to derive the quiescent loss rate

Matta, Abraham "Ibrahim"

124

Effects of overlay designs on reliability of flexible pavements  

Microsoft Academic Search

Management of flexible pavements requires timely application of preventive maintenance and rehabilitation actions such as overlays. These actions are an integral part of a design strategy that minimises the use of recourses over the pavement's life-cycle. The objective of this paper is to develop a reliability model for flexible pavements that accounts for the effects of overlay designs. In this

Vighnesh P. Deshpande; Ivan D. Damnjanovic; Paolo Gardoni

2010-01-01

125

NEBLO: Anonymity in a Structured Overlay Giuseppe Ciaccio  

E-print Network

it impossible for a "small" coalition of malicious peers to correlate overlay addresses to hosts for censorship, censorship-resistant 1. Introduction and motivation Overlay networks have been receiving a lot of atten- tion to the physical Internet address of the destination host. It must be made difficult for an adversary to build

Ciaccio, Giuseppe

126

Dynamis: Dynamic Overlay Service Composition for Distributed Stream Processing  

Microsoft Academic Search

Advanced Internet services, such as those for processing data streams from sensor networks, often need to support complex operations to meet the needs of multiple user groups. Exploiting resources of distributed nodes to compose services in an overlay network is one approach to addressing this problem. To compose services, an overlay infrastructure needs to support dynamic adaptation to varying conditions

Farshad A. Samimi; Philip K. Mckinley

2008-01-01

127

LANDSAT US standard catalog, 1-30 April 1976. [LANDSAT imagery for April, 1976  

NASA Technical Reports Server (NTRS)

Information regarding the availability of LANDSAT imagery processed and input to the data files by the NASA Data Processing Facility is published on a monthly basis. The U.S. Standard Catalog includes imagery covering the continental United States, Alaska and Hawaii. The Non-U.S. Standard Catalog identifies all the remaining coverage. Sections 1 and 2 describe the contents and format for the catalogs and the associated microfilm. Section 3 provides a cross-reference defining the beginning and ending dates for LANDSAT cycles. Sections 4 and 5 cover LANDSAT-1 and LANDSAT-2 coverage, respectively.

1976-01-01

128

LANDSAT: US standard catalog, 1-31 January 1976. [LANDSAT imagery for January 1976  

NASA Technical Reports Server (NTRS)

Information regarding the availability of LANDSAT imagery processed and input to the data files by the NASA Data Processing Facility is published on a monthly basis. The U.S. Standard Catalog includes imagery covering the continental United States, Alaska and Hawaii. The Non-U.S. Standard Catalog identifies all the remaining coverage. Section 1 and 2 describe the contents and format for the catalogs and the associated microfilm. Section 3 provides a cross-reference defining the beginning and ending dates for LANDSAT cycles. Sections 4 and 5 cover LANDSAT-1 and LANDSAT-2 coverage, respectively.

1976-01-01

129

Multicast and Bulk Lookup in Structured Overlay Networks  

NASA Astrophysics Data System (ADS)

Structured overlay networks are often used to implement a Distributed Hash Table (DHT) abstraction. In this chapter, we argue that structured overlay networks are suitable for doing efficient group communication. We provide algorithms that enable a node to efficiently broadcast a message to all other nodes in a structured overlay network, without inducing any redundant messages. We also provide algorithms that enasble any node to efficiently send a message to all nodes in a specified set of identifiers. Such algorithms have found usage in many structured overlay networks that implement range queries. Similarly, we provide algorithms that enable any node to efficiently send a message to the nodes responsible for any of the identifiers in a specified set of identifiers. Finally, we look at a case study of implementing efficient Application Level Multicast (ALM) using the group communication algorithms on top of structured overlay networks.

Ghodsi, Ali

130

LANDSAT-4 image data quality analysis  

NASA Technical Reports Server (NTRS)

Classification performance from LANDSAT 4 TM and MSS data is evaluated using the SECHO computer program. The data accuracy is compared using forest, corn, soybeans, bare soil, grass, water, and urban areas as classes for investigation.

Anuta, P. E.

1984-01-01

131

LANDSAT-4 Scientific Characterization: Early Results Symposium  

NASA Technical Reports Server (NTRS)

Radiometric calibration, geometric accuracy, spatial and spectral resolution, and image quality are examined for the thematic mapper and the multispectral band scanner on LANDSAT 4. Sensor performance is evaluated.

1983-01-01

132

Landsat: A Space Age Water Gauge  

NASA Video Gallery

Water specialists Rick Allen, Bill Kramber and Tony Morse use Landsat thermal band data to measure the amount of water evaporating from the soil and transpiring from plants? leaves ? a process call...

133

Landsat and Apollo: The Forgotten Legacy  

Microsoft Academic Search

This paper demonstrates that Landsat was fundamentally a result of the Apollo Program. The U.S. Geological Survey's EROS proposal of 1966, which eventually led to Landsat, was stimulated largely by the demonstrated utility of 1100 orbital photographs from the Gemini missions, Gemini being solely preparation for Apollo. In addition, Earth-oriented remote sensing research sponsored by NASA in the mid-1 960s,

Paul D. Lowman

1999-01-01

134

Weld overlay cladding with iron aluminides  

SciTech Connect

The hot and cold cracking tendencies of some early iron aluminide alloy compositions have limited their use in applications where good weldability is required. Using hot crack testing techniques invented at ORNL, and experimental determinations of preheat and postweld heat treatment needed to avoid cold cracking, we have developed iron aluminide filler metal compositions which can be successfully used to weld overlay clad various substrate materials, including 9Cr-1Mo steel, 2-1/4Cr-1Mo steel, and 300-series austenitic stainless steels. Dilution must be carefully controlled to avoid crack-sensitive deposit compositions. The technique used to produce the current filler metal compositions is aspiration-casting, i.e. drawing the liquid from the melt into glass rods. Future development efforts will involve fabrication of composite wires of similar compositions to permit mechanized gas tungsten arc (GTA) and/or gas metal arc (GMA) welding.

Goodwin, G.M. [Oak Ridge National Lab., TN (United States)

1995-08-01

135

Weld overlay cladding with iron aluminides  

SciTech Connect

The hot and cold cracking tendencies of some early iron aluminide alloy compositions limited their use to applications where good weldability was not required. Considerable progress has been made toward improving this situation. Using hot crack testing techniques developed at ORNL and a systematic study of alloy compositional effects, we have established a range of compositions within which hot cracking resistance is very good, essentially equivalent to stainless steel. Cold cracking, however, remains an issue, and extensive efforts are continuing to optimize composition and welding parameters, especially preheat and postweld heat treatment, to minimize its occurrence. In terms of filler metal and process development, we have progressed from sheared strip through aspiration cast rod and shielded metal arc electrodes to the point where we can now produce composite wire with a steel sheath and aluminum core in coil form, which permits the use of both the gas tungsten arc and gas metal arc processes. This is a significant advancement in that the gas metal arc process lends itself well to automated welding, and is the process of choice for commercial weld overlay applications. Using the newly developed filler metals, we have prepared clad specimens for testing in a variety of environments both in-house and outside ORNL, including laboratory and commercial organizations. As a means of assessing the field performance of this new type of material, we have modified several non-pressure boundary boiler components, including fuel nozzles and port shrouds, by introducing areas of weld overlay in strategic locations, and have placed these components in service in operating boilers for a side-by-side comparison with conventional corrosion-resistant materials.

Goodwin, G.M.

1996-11-01

136

Landsat and water: case studies of the uses and benefits of landsat imagery in water resources  

USGS Publications Warehouse

The Landsat program has been collecting and archiving moderate resolution earth imagery since 1972. The number of Landsat users and uses has increased exponentially since the enactment of a free and open data policy in 2008, which made data available free of charge to all users. Benefits from the information Landsat data provides vary from improving environmental quality to protecting public health and safety and informing decision makers such as consumers and producers, government officials and the public at large. Although some studies have been conducted, little is known about the total benefit provided by open access Landsat imagery. This report contains a set of case studies focused on the uses and benefits of Landsat imagery. The purpose of these is to shed more light on the benefits accrued from Landsat imagery and to gain a better understanding of the program’s value. The case studies tell a story of how Landsat imagery is used and what its value is to different private and public entities. Most of the case studies focus on the use of Landsat in water resource management, although some other content areas are included.

Serbina, Larisa O.; Miller, Holly M.

2014-01-01

137

LANDSAT: US Standard Catalog, 1-31 December 1976. [LANDSAT imagery for December 1976  

NASA Technical Reports Server (NTRS)

The U.S. Standard Catalog lists U.S. imagery acquired by LANDSAT 1 and LANDSAT 2 which has been processed and input to the data files during the referenced month. Data, such as date acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found are also given.

1976-01-01

138

Asphaltic concrete overlays of rigid and flexible pavements  

NASA Astrophysics Data System (ADS)

The development of a mechanistic approach to overlay thickness selection is described. The procedure utilizes a deflection analysis to determine pavement rehabilitation needs. Design guides for selecting the overlay thickness are presented. Tolerable deflection-traffic load relationships and the deflection attenuation properties of asphaltic concrete were developed, representing the subgrade support conditions and properties of materials used in Louisiana. All deflection measurements on asphaltic concrete were corrected for the effect of temperature. Deflection measurements taken before and after overlay were also adjusted to minimize the effects of seasonal subgrade moisture variation.

Kinchen, R. W.; Temple, W. H.

1980-10-01

139

Mitigating Attacks Against Measurement-Based Adaptation Mechanisms in Unstructured Multicast Overlay Networks  

Microsoft Academic Search

Many multicast overlay networks maintain application-specific performance goals such as bandwidth, latency, jitter and loss rate by dynamically changing the overlay structure using measurement-based adaptation mechanisms. This results in an unstructured overlay where no neighbor selection constraints are imposed. Although such networks provide resilience to benign failures, they are susceptibl e to attacks conducted by adversaries that compromise overlay nodes.

Aaron Walters; David John Zage; Cristina Nita-rotaru

2006-01-01

140

A framework for mitigating attacks against measurement-based adaptation mechanisms in unstructured multicast overlay networks  

Microsoft Academic Search

Many multicast overlay networks maintain application-specific performance goals by dynamically adapting the overlay structure when the monitored performance becomes inadequate. This adaptation results in an unstructured overlay where no neighbor selection constraints are imposed. Although such networks provide resilience to benign failures, they are susceptible to attacks conducted by adversaries that compromise overlay nodes. Previous defense solutions proposed to address

Aaron Walters; David Zage; Cristina Nita-Rotaru

2008-01-01

141

Keynote 2: using randomized techniques to build scalable intrusion-tolerant overlay networks  

Microsoft Academic Search

Overlay networks provide important routing functionality not easily supported directly by the Internet. Distributed Hash Tables (DHTs) have been proposed to support such overlay networks. While it is often straightforward to support overlay networks on DHTs, this choice can be questioned. DHTs dictate routes that are not optimal, and DHTs are hard to secure. As overlay networks are beginning to

Robbert van Renesse

2005-01-01

142

Using randomized techniques to build scalable intrusion-tolerant overlay networks (Keynote)  

Microsoft Academic Search

Overlay networks provide important routing func- tionality not easily supported directly by the Inter- net. Distributed Hash Tables (DHTs) have been pro- posed to support such overlay networks. While it is often straightforward to support overlay networks on DHTs, this choice can be questioned. DHTs dic- tate routes that are not optimal, and DHTs are hard to secure. As overlay

Robbert Van Renesse

2005-01-01

143

166 IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING, VOL. 17, NO. 2, MAY 2004 Optimized Overlay Metrology Marks  

E-print Network

Metrology Marks: Theory and Experiment Mike Adel, Mark Ghinovker, Boris Golovanevsky, Pavel Izikson, Elyakim--In this paper, we provide a detailed analysis of overlay metrology mark and find the mapping between various, Fisher information matrix, grating marks, overlay mark, overlay mark fidelity, overlay metrology. I

Bruckstein, Alfred M.

144

Full-Information Lookups for Peer-to-Peer Overlays  

E-print Network

Most peer-to-peer lookup schemes keep a small amount of routing state per node, typically logarithmic in the number of overlay nodes. This design assumes that routing information at each member node must be kept small so ...

Rodrigues, Rodrigo

145

CNPq/INPE-LANDSAT system report of activities  

NASA Technical Reports Server (NTRS)

The status of the Brazilian LANDSAT facilities and the results achieved are presented. In addition, a LANDSAT product sales/distribution analysis is provided. Data recording and processing capabilities and planned products are addressed.

Parada, N. D. J. (principal investigator); Barbosa, M. N.

1982-01-01

146

Overlay Text Retrieval From Video Scene  

NASA Astrophysics Data System (ADS)

The rapid growth of video data leads to an urgent demand for efficient and true contentbased browsing and retrieving systems. In response to such needs, various video content analysis schemes using one or a combination of image, audio, and text information in videos have been proposed to parse, index, or abstract massive amount of data text in video is a very compact and accurate clue for video indexing and summarization. Most video text detection and extraction methods hold assumptions on text color, background contrast, and font style. Moreover, few methods can handle multilingual text well since different languages may have quite different appearances. In this paper, an efficient overlay text detection and extraction method is implemented which deals with complex backgrounds. Based on our observation that there exist transient colors between inserted text and its adjacent background. It is robust with respect to font size, style text, color, orientation and noise and can be used in a large variety of application fields such as mobile robot navigation vehicle license detection and recognition, object identification , document retrieving, etc.

Manohar, K.; Irfan, S.; Sravani, K.

2013-03-01

147

Perturbation-Resistant and Overlay-Independent Resource Discovery  

Microsoft Academic Search

This paper realizes techniques supporting the position that strategies for resource location and discovery in dis- tributed systems should be both perturbation-resistant and overlay-independent. Perturbation-resistance means that inserts and lookups must be robust to ordinary stresses such as node perturbation, which may arise out of conges- tion, competingclient applications,or user churn. Overlay- independence implies that the insert and lookup strategies,

Steven Y. Ko; Indranil Gupta

2005-01-01

148

Community overlays upon real-world complex networks  

NASA Astrophysics Data System (ADS)

Many networks are characterized by the presence of communities, densely intra-connected groups with sparser inter-connections between groups. We propose a community overlay network representation to capture large-scale properties of communities. A community overlay G o can be constructed upon a network G, called the underlying network, by (a) aggregating each community in G as a node in the overlay G o ; (b) connecting two nodes in the overlay if the corresponding two communities in the underlying network have a number of direct links in between, (c) assigning to each node/link in the overlay a node/link weight, which represents e.g. the percentage of links in/between the corresponding underlying communities. The community overlays have been constructed upon a large number of real-world networks based on communities detected via five algorithms. Surprisingly, we find the following seemingly universal properties: (i) an overlay has a smaller degree-degree correlation than its underlying network ? o ( D l+, D l-) < ?( D l+, D l-) and is mostly disassortative ? o ( D l+, D l-) < 0; (ii) a community containing a large number W i of nodes tends to connect to many other communities ? o ( W i , D i ) > 0. We explain the generic observation (i) by two facts: (1) degree-degree correlation or assortativity tends to be positively correlated with modularity; (2) by aggregating each community as a node, the modularity in the overlay is reduced and so is the assortativity. The observation (i) implies that the assortativity of a network depends on the aggregation level of the network representation, which is illustrated by the Internet topology at router and AS level.

Ge, X.; Wang, H.

2012-01-01

149

Rehabilitation of continuously reinforced concrete pavements using overlays  

E-print Network

REHABILITATION OF CONTINUOUSLY REINFORCED CONCRETE PAVEMENTS USING OVERLAYS A Thesis by SOUMYA SRIRAMAN Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... August 1993 Major Subject: Civil Engineering REHABILITATION OF CONTINUOUSLY REINFORCED CONCRETE PAVEMENTS USING OVERLAYS A Thesis by SOUMYA SRIRAMAN Submitted to Texas A&M University in partial fulfillment of the requirements for the degree...

Sriraman, Soumya

2012-06-07

150

Synthetic aperture radar/LANDSAT MSS image registration  

NASA Technical Reports Server (NTRS)

Algorithms and procedures necessary to merge aircraft synthetic aperture radar (SAR) and LANDSAT multispectral scanner (MSS) imagery were determined. The design of a SAR/LANDSAT data merging system was developed. Aircraft SAR images were registered to the corresponding LANDSAT MSS scenes and were the subject of experimental investigations. Results indicate that the registration of SAR imagery with LANDSAT MSS imagery is feasible from a technical viewpoint, and useful from an information-content viewpoint.

Maurer, H. E. (editor); Oberholtzer, J. D. (editor); Anuta, P. E. (editor)

1979-01-01

151

Residual stresses in weld overlay tubes: A finite element study  

SciTech Connect

Residual stresses and strains in a tube with circumferential weld overlay were analyzed by the finite element (FE) method. The objective of this work was to develop and verify a FE model, to determine the magnitude and distribution of residual stresses in the weld overlay tube, and to evaluate the significance of two contributing factors to residual stress: (1) difference in material properties between tube and weld material, and (2) thermal gradients in the weld. An axisymmetric FE model was developed to simulate the circumferential two-layer welding process of alloy 625 overlay on SA210 tube. The first layer was modeled as a gas metal arc welding process with filler metal, whereas the autogenous gas tungsten arc welding process was modeled for the second layer. Neutron diffraction technique was used to experimentally determine residual elastic strains in the weld overlay tube. Comparison with the FE results shows overall good agreement. Both the experimental and FE results show high compressive stresses at the inside tube surface and high tensile stresses in the weld overlay. This suggests that weld overlay may be used to relieve tensile or produce compressive stresses at the inside tube surface, which is significant for applications where crack initiation is found at the root pass of the joining weld.

Taljat, B.; Zacharia, T.; Wang, X.L.; Keiser, J.R. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.; Feng, Z. [Edison Welding Inst., Columbus, OH (United States); Jirinec, M.J. [Welding Services, Inc., Norcross, GA (United States)

1997-01-03

152

Overlay improvements using a real time machine learning algorithm  

NASA Astrophysics Data System (ADS)

While semiconductor manufacturing is moving towards the 14nm node using immersion lithography, the overlay requirements are tightened to below 5nm. Next to improvements in the immersion scanner platform, enhancements in the overlay optimization and process control are needed to enable these low overlay numbers. Whereas conventional overlay control methods address wafer and lot variation autonomously with wafer pre exposure alignment metrology and post exposure overlay metrology, we see a need to reduce these variations by correlating more of the TWINSCAN system's sensor data directly to the post exposure YieldStar metrology in time. In this paper we will present the results of a study on applying a real time control algorithm based on machine learning technology. Machine learning methods use context and TWINSCAN system sensor data paired with post exposure YieldStar metrology to recognize generic behavior and train the control system to anticipate on this generic behavior. Specific for this study, the data concerns immersion scanner context, sensor data and on-wafer measured overlay data. By making the link between the scanner data and the wafer data we are able to establish a real time relationship. The result is an inline controller that accounts for small changes in scanner hardware performance in time while picking up subtle lot to lot and wafer to wafer deviations introduced by wafer processing.

Schmitt-Weaver, Emil; Kubis, Michael; Henke, Wolfgang; Slotboom, Daan; Hoogenboom, Tom; Mulkens, Jan; Coogans, Martyn; ten Berge, Peter; Verkleij, Dick; van de Mast, Frank

2014-04-01

153

Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS)  

NASA Technical Reports Server (NTRS)

The Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) project is creating a record of forest disturbance and regrowth for North America from the Landsat satellite record, in support of the carbon modeling activities. LEDAPS relies on the decadal Landsat GeoCover data set supplemented by dense image time series for selected locations. Imagery is first atmospherically corrected to surface reflectance, and then change detection algorithms are used to extract disturbance area, type, and frequency. Reuse of the MODIS Land processing system (MODAPS) architecture allows rapid throughput of over 2200 MSS, TM, and ETM+ scenes. Initial ("Beta") surface reflectance products are currently available for testing, and initial continental disturbance products will be available by the middle of 2006.

Masek, Jeffrey G.

2006-01-01

154

LANDSAT-D data format control book. Volume 5: (Payload)  

NASA Technical Reports Server (NTRS)

The LANDSAT-D flight segment payload is the thematic mapper and the multispectral scanner. Narrative and visual descriptions of the LANDSAT-D payload data handling hardware and data flow paths from the sensing instruments through to the GSFC LANDSAT-D data management system are provided. Key subsystems are examined.

Andrew, H.

1981-01-01

155

Study of atmospheric diffusion using LANDSAT  

NASA Technical Reports Server (NTRS)

The parameters of diffusion patterns of atmospheric pollutants under different conditions were investigated for use in the Gaussian model for calculation of pollution concentration. Value for the divergence pattern of concentration distribution along the Y axis were determined using LANDSAT images. Multispectral scanner images of a point source plume having known characteristics, wind and temperature data, and cloud cover and solar elevation data provided by LANDSAT, were analyzed using the 1-100 system for image analysis. These measured values are compared with pollution transport as predicted by the Pasquill-Gifford, Juelich, and Hoegstroem atmospheric models.

Torsani, J. A.; Viswanadham, Y.

1982-01-01

156

Radiometric cross-calibration of the Landsat7 ETM+ and Landsat5 TM sensors based on tandem data sets  

Microsoft Academic Search

Early in its mission, the Landsat-7 spacecraft was temporarily placed in a “tandem” orbit very close to that of the Landsat-5 spacecraft in order to facilitate the establishment of sensor calibration continuity between the Landsat-7 Enhanced Thematic Mapper Plus (ETM+) and Landsat-5 Thematic Mapper (TM) sensors. The key period for the tandem configuration was June 1–4, 1999, during which hundreds

P. m. Teillet; J. l. Barker; B. l. Markham; R. R Irish; G. Fedosejevs; J. c. Storey

2001-01-01

157

Interplanetary Overlay Network Bundle Protocol Implementation  

NASA Technical Reports Server (NTRS)

The Interplanetary Overlay Network (ION) system's BP package, an implementation of the Delay-Tolerant Networking (DTN) Bundle Protocol (BP) and supporting services, has been specifically designed to be suitable for use on deep-space robotic vehicles. Although the ION BP implementation is unique in its use of zero-copy objects for high performance, and in its use of resource-sensitive rate control, it is fully interoperable with other implementations of the BP specification (Internet RFC 5050). The ION BP implementation is built using the same software infrastructure that underlies the implementation of the CCSDS (Consultative Committee for Space Data Systems) File Delivery Protocol (CFDP) built into the flight software of Deep Impact. It is designed to minimize resource consumption, while maximizing operational robustness. For example, no dynamic allocation of system memory is required. Like all the other ION packages, ION's BP implementation is designed to port readily between Linux and Solaris (for easy development and for ground system operations) and VxWorks (for flight systems operations). The exact same source code is exercised in both environments. Initially included in the ION BP implementations are the following: libraries of functions used in constructing bundle forwarders and convergence-layer (CL) input and output adapters; a simple prototype bundle forwarder and associated CL adapters designed to run over an IPbased local area network; administrative tools for managing a simple DTN infrastructure built from these components; a background daemon process that silently destroys bundles whose time-to-live intervals have expired; a library of functions exposed to applications, enabling them to issue and receive data encapsulated in DTN bundles; and some simple applications that can be used for system checkout and benchmarking.

Burleigh, Scott C.

2011-01-01

158

LANDSAT Imagery for Everyone The U.S. Geological Survey (USGS) Landsat 35-year  

E-print Network

://landsat.usgs.gov. Pierre Morel Honored at European Geophysical Union Meeting GEWEX Welcomes New Director of WCRP Joint Layer Cloud Working Group (BLCWG) has conducted a number of workshops devoted to idealized case stud

159

LANDSAT-1 and LANDSAT-2 flight evaluation report, 23 April - 23 July 1976  

NASA Technical Reports Server (NTRS)

LANDSAT 1 and 2 operations were described, giving detailed charts and tables of their performances since 1972. Orbital parameters, attitude control subsystem, telemetry subsystem, orbit adjust subsystem, and magnetic moment compensating assembly were some of the main parameters discussed.

1976-01-01

160

LANDSAT D data processing facility study  

NASA Technical Reports Server (NTRS)

Mission planning of the LANDSAT D is discussed which will present several major advances in the spacecraft, sensor (Thematic Mapper), ground systems and overall system design. The system provides for two data links-direct satellite to ground, and via the Tracking and Data Relay Satellite.

1976-01-01

161

LANDSAT-4 image data quality analysis  

NASA Technical Reports Server (NTRS)

Methods were developed for estimating point spread functions from image data. Roads and bridges in dark backgrounds are being examined as well as other smoothing methods for reducing noise in the estimated point spread function. Tomographic techniques were used to estimate two dimensional point spread functions. Reformatting software changes were implemented to handle formats for LANDSAT-5 data.

Anuta, P. E.

1984-01-01

162

Landsat non-US standard catalog  

NASA Technical Reports Server (NTRS)

The Non-U.S. Standard Catalog lists Non-U.S. imagery acquired by Landsat 1 and 2 which was processed and input to the data files during the referenced month. Data, such as date acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found are also given.

1975-01-01

163

Mission to Earth: Landsat Views the World.  

ERIC Educational Resources Information Center

Presented is a compendium of the outstanding Landsat scenes of the Earth's surface. It is directed to college and high school teachers, resource specialists, researchers, outdoorsmen, travelers, the general public, and serious students of geology or geography. The images are presented in color and at a scale and resolution that specify many…

Short, Nicholas M.; And Others

164

TRIMLINE MAPPING FROM MULTISPECTRAL LANDSAT ETM+ IMAGERY  

Microsoft Academic Search

Multispectral Landsat ETM+ imagery is used to study the ice-marginal region in the vicinity of Jakobshavn Isfjord, west Greenland. In particular, the trimline indicating margin retreat since the maximum stand attained during the Little Ice Age maximum is recons- tructed, and compared with earlier maps based on aerial photo- grammetry and ground surveys. Applying supervised classification, fourteen different surface types

Bea M. CSATHO; Cornelis J. VAN DER VEEN; Catherine M. TREMPER

165

A textural image of Algiers. [Landsat  

NASA Technical Reports Server (NTRS)

A geometrical operator (ETOILE) for processing LANDSAT images is presented. The operator exploits the fact that in urban areas lines are much closer and more complex. To distinguish town from countryside, the operator is sensitive to a high frequency of change in lineaments. It is used in a classic multidimensional classification scheme. The operator was used to map urbanisation of the area around Algiers.

Rimbert, S.; Serradj, A.

1984-01-01

166

Software for Viewing Landsat Mosaic Images  

NASA Technical Reports Server (NTRS)

A Windows-based computer program has been written to enable novice users (especially educators and students) to view images of large areas of the Earth (e.g., the continental United States) generated from image data acquired in the Landsat observations performed circa the year 1990. The large-area images are constructed as mosaics from the original Landsat images, which were acquired in several wavelength bands and each of which spans an area (in effect, one tile of a mosaic) of 5 in latitude by approximately equal to 6 degrees in longitude. Whereas the original Landsat data are registered on a universal transverse Mercator (UTM) grid, the program converts the UTM coordinates of a mouse pointer in the image to latitude and longitude, which are continuously updated and displayed as the pointer is moved. The mosaic image currently on display can be exported as a Windows bit-map file. Other images (e.g., of state boundaries or interstate highways) can be overlaid on Landsat mosaics. The program interacts with the user via standard toolbar, keyboard, and mouse user interfaces. The program is supplied on a compact disk along with tutorial and educational information.

Watts, Jack; Farve, Catherine L.; Harvey, Craig

2002-01-01

167

Software for Viewing Landsat Mosaic Images  

NASA Technical Reports Server (NTRS)

A Windows-based computer program has been written to enable novice users (especially educators and students) to view images of large areas of the Earth (e.g., the continental United States) generated from image data acquired in the Landsat observations performed circa the year 1990. The large-area images are constructed as mosaics from the original Landsat images, which were acquired in several wavelength bands and each of which spans an area (in effect, one tile of a mosaic) of approx. 5 in latitude by approx. 6 deg in longitude. Whereas the original Landsat data are registered on a universal transverse Mercator (UTM) grid, the program converts the UTM coordinates of a mouse pointer in the image to latitude and longitude, which are continuously updated and displayed as the pointer is moved. The mosaic image currently on display can be exported as a Windows bit-map file. Other images (e.g., of state boundaries or interstate highways) can be overlaid on Landsat mosaics. The program interacts with the user via standard toolbar, keyboard, and mouse user interfaces. The program is supplied on a compact disk along with tutorial and educational information.

2002-01-01

168

Operational Atmospheric Correction of Landsat TM Data  

Microsoft Academic Search

The recent algorithms developed for biophysical variables assessment require accurate surface reflectance measurements. This article describes algorithms used for atmospheric correction of Landsat Thematic Mapper (TM) data. Atmospheric corrections include Rayleigh scattering, gaseous absorption, and aerosol scattering in three visible channels (480 nm, 560 nm, and 660 nm), and the near-infrared channel (830 nm). Atmospheric constituents such as water vapor

Hassan Ouaidrari; Eric F. Vermote

1999-01-01

169

The Landsat Data Purchase and ESAD  

NASA Technical Reports Server (NTRS)

The Earth Science Applications Directorate (ESAD) purchases satellite imagery for The Scientific Data Purchase (SDP) Project. SDP allows a variety of customers in turn to purchase Landsat, IKONOS, and other data. The SDP customer base includes includes private companies, universities, and government agencies. SDP customers are required to register and receive clearance.

Policelli, Fritz; Fletcher, Rose

2001-01-01

170

LANDSAT-4 to ground station interface description  

NASA Technical Reports Server (NTRS)

The LANDSAT 4 to ground station interface is described in detail. The radiometric specifications, internal calibration, sensor output format, and data processing constants for the multispectral scanner and the thematic mapper are discussed. The mission payload telemetry, onboard computer telemetry, and engineering telemetry formats are described. In addition, the telemetry time signals and the onboard clock resetting procedure are addressed.

1983-01-01

171

LANDSAT-D Mission System Industry Briefing  

NASA Technical Reports Server (NTRS)

Viewgraphs and photographs depict the scope and purpose of the LANDSAT 4 mission as well as all satellite systems. The components and major functions of the flight and ground segments, operational support, communication links, and the hardware and interfaces for processing MSS and TM images are covered.

1982-01-01

172

Instructional geographic information science Map overlay and spatial abilities  

NASA Astrophysics Data System (ADS)

The fundamental goal of this study is to determine if the complex spatial concept of map overlay can be effectively learned by young adolescents through the utilization of an instructional technique based within the foundations of Instructional Geographic Information Science (InGIScience). Percent correct and reaction times were the measures used to analyze the ability of young adolescents to learn the intersect, erase, and union functions of map overlay. The ability to solve for missing inputs, output, or function was also analyzed. Young adolescents of the test group scored higher percent correct and recorded faster reaction times than those of the control group or adults of the expert group by the end of the experiment. The intersect function of map overlay was more difficult in terms of percent correct and reaction time than the erase or union functions. Solving for the first or second input consistently resulted in lower percent correct and higher reaction times throughout the experiment. No overall performance differences were shown to exist between males and females. Results of a subjective "real-world" test also indicated learning by young adolescents. This study has shown that the practice of repetitive instruction and testing has proven effective for enhancing spatial abilities with regard to the map overlay concept. This study found that with practice, young adolescents can learn the map overlay concept and perform at levels equal to or greater than adults. This study has helped to answer the question of whether this development of spatial abilities is possible.

Tricot, Thomas Alexander, II

173

Cooperative Resource Pricing in Service Overlay Networks for Mobile Agents  

NASA Astrophysics Data System (ADS)

The success of peer-to-peer overlay networks depends on cooperation among participating peers. In this paper, we investigate the degree of cooperation among individual peers required to induce globally favorable properties in an overlay network. Specifically, we consider a resource pricing problem in a market-oriented overlay network where participating peers sell own resources (e.g., CPU cycles) to earn energy which represents some money or rewards in the network. In the resource pricing model presented in this paper, each peer sets the price for own resource based on the degree of cooperation; non-cooperative peers attempt to maximize their own energy gains, while cooperative peers maximize the sum of own and neighbors' energy gains. Simulation results are presented to demonstrate that the network topology is an important factor influencing the minimum degree of cooperation required to increase the network-wide global energy gain.

Nakano, Tadashi; Okaie, Yutaka

174

Enabling New Research with Free Landsat Data  

NASA Astrophysics Data System (ADS)

Landsat 1 launched in February 1972. This began a more than 37-year mission to provide the world with mid-resolution satellite data coverage. Although data were always publically available, the cost of the data has always been prohibitive for either broad regional to global studies, or research requiring long-term studies with high temporal frequency. In order to overcome the cost-barrier, the entire Landsat archive, over 2.3 million scenes, was offered for free at the end of December 2008. Over 1,000,000 scenes were downloaded in the first ten months, surpassing all data distribution in the history of the Landsat mission combined. Technical improvements for radiometric and geometric consistency are still underway, over a year later. In addition, capabilities for bulk metadata access and bulk downloading were just implemented in the fall of 2009. Data does not permanently reside in a processed format. Data is processed as requested, or, in some cases, as soon as it is acquired, and then rolled off as improved processing parameters are developed or space on the servers is required. This means that data that is downloaded one day, may not be available the next day. But, this approach precludes major reprocessing efforts while maintaining a quick turnaround time for data orders. Depending on demand, maximum processing time is around 27 hours, averages 5 hours, with a minimum of around 10 minutes. Research applications that require bulk metadata access are now able to download as much of the archive metadata as they need. Path/row or latitude/longitude searches are available for the entire Landsat archive. Entire metadata records are not included, only those regarded as important to traditional scene selection, such as cloud cover and quality scores. There is only one Landsat data product, a geo-rectified, terrain-corrected product. For sophisticated users who may want an alternative ‘recipe’ for their data, an alternate projection or resampling algorithm, access to Level 0 data has just become available. Independently created software will be required to read and process these data. In all, the Landsat Project has every interest to enable research that requires a broadening of geographic and temporal coverage at the mid-resolution scale. We hope to prevent the need for individual long-term archive building by providing any scene at any time with the most up-to-date processing parameters.

Headley, R.

2009-12-01

175

Landsat: a global land imaging program  

USGS Publications Warehouse

Landsat satellites have continuously acquired space-based images of the Earth's land surface, coastal shallows, and coral reefs across four decades. The Landsat Program, a joint effort of the U.S. Geological Survey (USGS) and the National Aeronautics and Space Administration (NASA), was established to routinely gather land imagery from space. In practice, NASA develops remote-sensing instruments and spacecraft, launches satellites, and validates their performance. The USGS then assumes ownership and operation of the satellites, in addition to managing all ground-data reception, archiving, product generation, and distribution. The result of this program is a visible, long-term record of natural and human-induced changes on the global landscape.

Byrnes, Raymond A.

2012-01-01

176

Wheat productivity estimates using LANDSAT data  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. Objective measurements of percent green wheat cover on May 21 were significantly correlated with yield, as were measurements of green LAI and LANDSAT data. Three data sets from the Finney test site were analyzed from LANDSAT passes on 22 November 1974, 15 April 1975, and 21 May 1975. After mean signal values in each band were computed for each sufficiently large wheat field, the mean values were correlated with the farmer estimates of wheat grain yield in order to assess relative information content. It is clear that the single best spectral temporal band for predicting yield is the 15 April red band (0.6-0.7 microns, band 5), with the 15 April green band (0.5-0.6 microns, band 4) a close second.

Nalepka, R. F.; Colwell, J. (principal investigators); Rice, D. P.

1976-01-01

177

LANDSAT-4 post launch report 1  

NASA Technical Reports Server (NTRS)

LANDSAT-4 (formerly LANDSAT-D) was launched successfully at 1:59 p.m. EDT on July 16, 1982, from Vandenberg Air Force Base. The Delta 3920 launch vehicle performed flawlessly and placed the satellite into the planned three sigma low orbit of 694 km. The lower orbit was selected to eliminate a retrograde maneuver for the orbit adjust burns necessary to place the satellite into its planned operational 16-day repeat track at 705 km. Spacecraft separation and the initiation of solar array depolyment occurred, over the Indian Ocean tracking station. Spacecraft attitude rates at separation were low, allowing the Earth sensor to immediately acquire the Earth with the momentum wheels and without use of the propulsion system. All systems activated as of noon on July 18, 1982, are performing well with no significant discrepancies reported.

1982-01-01

178

Power Control in Spectrum Overlay Networks: How to Cross a Multi-Lane Highway  

E-print Network

Power Control in Spectrum Overlay Networks: How to Cross a Multi-Lane Highway Wei Ren, Qing Zhao source to destina- tion in spectrum overlay networks as crossing a multi-lane highway, each lane having

Islam, M. Saif

179

Landsat Data Continuity Mission Calibration and Validation  

NASA Technical Reports Server (NTRS)

The primary payload for the Landsat Data Continuity Mission (LDCM) is the Operational Land Imager (OLI), being built by Ball Aerospace and Technologies, under contract to NASA. The OLI has spectral bands similar to the Landsat-7 ETM+, minus the thermal band and with two new bands, a 443 nm band and 1375 nm cirrus detection band. On-board calibration systems include two solar diffusers (routine and pristine), a shutter and three sets of internal lamps (routine, backup and pristine). Being a pushbroom opposed to a whiskbroom design of ETM+, the system poses new challenges for characterization and calibration, chief among them being the large focal plane with 75000+ detectors. A comprehensive characterization and calibration plan is in place for the instrument and the data throughout the mission including Ball, NASA and the United States Geological Survey, which will take over operations of LDCM after on-orbit commissioning. Driving radiometric calibration requirements for OLI data include radiance calibration to 5% uncertainty (1 q); reflectance calibration to 3% uncertainty (1 q) and relative (detector-to-detector) calibration to 0.5% (J (r). Driving geometric calibration requirements for OLI include bandto- band registration of 4.5 meters (90% confidence), absolute geodetic accuracy of 65 meters (90% CE) and relative geodetic accuracy of 25 meters (90% CE). Key spectral, spatial and radiometric characterization of the OLI will occur in thermal vacuum at Ball Aerospace. During commissioning the OLI will be characterized and calibrated using celestial (sun, moon, stars) sources and terrestrial sources. The USGS EROS ground processing system will incorporate an image assessment system similar to Landsat-7 for characterization and calibration. This system will have the added benefit that characterization data will be extracted as part of the normal image data processing, so that the characterization data available will be significantly larger than for Landsat-7 ETM+.

Markham, Brian L.; Dabney, Philip W.; Storey, James C.; Morfitt, Ron; Knight, Ed; Kvaran, Geir; Lee, Kenton

2008-01-01

180

Factors affecting snow assessment from LANDSAT data  

NASA Technical Reports Server (NTRS)

Problems associated with using LANDSAT as a snow monitoring satellite are studied. Data cover problems of slop hinderance in thematic mapping of snow and detection of snow in forested areas. It was concluded that if detector saturation threshold is raised and the upper spectral limit of the MSS is extended, snow extent mapping will be improved along with the likelihood of monitoring some aspects of the physical condition of snow pack.

Mcginnis, D. F., Jr.; Mcmillan, M. C.; Wiesnet, D. R.

1975-01-01

181

Landsat-D, about to be reality  

NASA Astrophysics Data System (ADS)

The space and ground segments of the Landsat-D thematic mapper (TM) for remote sensing of a 185 km swath with 30 m resolution are described. Scanning the full earth once every 16 days from its 705 km sunsynchronous orbit, Landsat-D will relay its data on the ku-band through the TDRSS satellite to a ground station. The X-band will also be used to transmit data directly to foreign and domestic ground stations; the S-band will be reserved for MSS data only. Landsat-D comprises the multimission modular spacecraft and the instrument module, which features the MSS and TM, a wideband communication subsystem, a solar array, and an L-band global positioning system. Three computers on the ground provide a high degree of automation for reception, storage, retrieval, back-up, and transmission of data and commands. Additionally, a van is equipped with transportable equipment, including an antenna. Procedures followed for image generation from the MSS and TM are detailed, noting storage at Goddard until dispersal of tapes under the direction of the EROS data center.

Aepli, T. C.; Capodici, S. C.; Busse, J. R.

182

Landsat digital enhancements for lineament detection  

NASA Astrophysics Data System (ADS)

Identification of lineaments has important ramifications in geology because lineaments can signify zones of both hazardous potential and economically valuable environments The synoptic view of local and regional lineament patterns by Landsat is a useful mapping technique in areas considered to be well mapped as well as in poorly mapped areas Image enhancement of digitally constructed Landsat images increases contrast and sharpness between geologic features and improves the recognition of subtle differences Five enhancement techniques are applied to Landsat digital data for lineament detection (1) mean value of all four bands, (2) principal components, (3) band ratio, (4) histogram equalization, and (5) high-pass digital filtering Of the five enhancement techniques evaluated, the principal components analysis identified the greatest number of lineaments and the greatest total length of the lineaments. All five techniques identified a significant amount of unique lineaments, which were not found by any other technique. Unique lineaments identified by each technique are combined through a composite process yielding a lineament interpretation which exceeds the detection capability of the principal components interpretation

Walsh, Stephen J.; Mynar, F.

1986-09-01

183

Laboratory evaluation of selected fabrics for reinforcement of asphaltic concrete overlays  

E-print Network

of reinforcing materials to bituminous overlays has been used for years in attempts to increase the tensile strength of overlays and make them less susceptible to reflection cracking. Early field trials employed steel reinforcing in the form of welded wi re... of reinforcing materials to bituminous overlays has been used for years in attempts to increase the tensile strength of overlays and make them less susceptible to reflection cracking. Early field trials employed steel reinforcing in the form of welded wi re...

Pickett, David L

2012-06-07

184

Performance Evaluation and Comparison of Tree and Ring Application-Layer Multicast Overlay Networks  

Microsoft Academic Search

Application-layer multicast (ALM) protocols differ in, among other aspects, the topology of the underlying overlay network (e.g., tree, mesh or ring). Therefore, comparing the performance of ALM overlay networks is an important step to- wards assessing the inherent advantages and\\/or limitations of each overlay network topology. In particular, ring-based ALM overlay networks have the advantages of (a) providing a con-

Ahmed Sobeih; Jun Wang; William Yurcik

185

Los Angeles Flyby  

NSDL National Science Digital Library

These scenes show Los Angeles and Burbank as seen by the Landsat Thematic Mapper (TM) instrument. The shortwave infrared (TM band 5), infrared (TM band 4), and visible green (TM band 2) channels are displayed in the images as red, green, and blue respectively. In this combination, barren and-or recently cultivated land appears red to pink, vegetation appears green, water is dark blue, and artificial structures of concrete and asphalt appear dark grey or black.

Allen, Jesse; Williams, Darrel

1999-04-09

186

Translation of Overlay Models of Student Knowledge for Relative Domains  

E-print Network

by all adaptive systems is the "new-user" problem. The models of those students who have just startedTranslation of Overlay Models of Student Knowledge for Relative Domains Based on Domain Ontology Mapping Sergey Sosnovsky1 , Peter Dolog2 , Nicola Henze3 , Peter Brusilovsky1 , Wolfgang Nejdl3 1 School

Dolog, Peter

187

Crosslayer Survivability in Overlay-IP-WDM Networks  

ERIC Educational Resources Information Center

As the Internet moves towards a three-layer architecture consisting of overlay networks on top of the IP network layer on top of WDM-based physical networks, incorporating the interaction between and among network layers is crucial for efficient and effective implementation of survivability. This dissertation has four major foci as follows:…

Pacharintanakul, Peera

2010-01-01

188

Strategyproof Mechanisms for Dynamic Multicast Tree Formation in Overlay Networks  

E-print Network

Strategyproof Mechanisms for Dynamic Multicast Tree Formation in Overlay Networks Selwyn Yuen the two scenarios of variable and single rate sessions, and further design distributed algorithms that maximizes its private utility, and may be reluctant to replicate and forward messages to downstream children

Li, Baochun

189

Virtual TCP Offload: Optimizing Ethernet Overlay Performance on Advanced Interconnects  

E-print Network

Virtual TCP Offload: Optimizing Ethernet Overlay Performance on Advanced Interconnects Zheng Cui Patrick G. Bridges John R. Lange Peter A. Dinda Department of CS University of New Mexico Albuquerque, NM 87131, USA {cuizheng,bridges}@cs.unm.edu Department of CS University of Pittsburgh Pittsburgh, PA 15260

Dinda, Peter A.

190

PAVEMENT OVERLAY THICKNESS EVALUATION USING GROUND PENTRATING RADAR (GPR)  

E-print Network

deflectometer (FWD), and ground penetrating radar (GPR). Core drilling provides very accurate pin point pavementPAVEMENT OVERLAY THICKNESS EVALUATION USING GROUND PENTRATING RADAR (GPR) Dwayne Harris, M.Sc., PG for determining pavement thickness are core drilling, falling weight deflectometer (FWD), and ground penetrating

Shan, Jie

191

Fireflies: scalable support for intrusion-tolerant network overlays  

Microsoft Academic Search

This paper describes and evaluates Fireflies, a scalable protocol for supporting intrusion-tolerant network overlays. While such a protocol cannot distinguish Byzantine nodes from correct nodes in general, Fireflies provides correct nodes with a reasonably current view of which nodes are live, as well as a pseudo-random mesh for communication. The amount of data sent by correct nodes grows linearly with

Hûavard Johansen; André Allavena; Robbert van Renesse

2006-01-01

192

Firefly-inspired Heartbeat Synchronization in Overlay Networks Ozalp Babaoglu  

E-print Network

flash messages using an algorithm inspired by mathematical models of firefly synchronization. We reFirefly-inspired Heartbeat Synchronization in Overlay Networks Ozalp Babaoglu Univ. Bologna, Italy synchronization in certain species of fireflies. In our protocol, nodes send flash messages to their neighbors

Jelasity, Márk

193

Recipient Anonymity in a Structured Overlay Giuseppe Ciaccio  

E-print Network

to request messages. Such a feature is of main concerns when designing censorship-resistant distributed of malicious peers to correlate overlay addresses to hosts for censorship or auditing purposes. 1. Introduction and message routing on top of the Internet addressing and packet routing scheme. Each host participating

Ciaccio, Giuseppe

194

Refined Overlay Power Management in the Home Environment  

E-print Network

power consumption makes up a large part of global energy consumption. These home appliances are not only efficient power management. Index Terms--Home network, Energy saving, Green network- ing, Overlay control communication [1]. Energy saving is recognized as a key issue in global warming and climate change. According

Boyer, Edmond

195

T-Man: Gossip-based Overlay Topology Mark Jelasity  

E-print Network

T-Man: Gossip-based Overlay Topology Management M´ark Jelasity and Ozalp Babaoglu University of nodes can also be interpreted as a topology. In this paper we propose a generic protocol, T-Man, intuitive and flexible manner. At the same time, the T-Man protocol involves only local communication

Jelasity, Márk

196

T-Man: Gossip-Based Overlay Topology Management  

E-print Network

T-Man: Gossip-Based Overlay Topology Management M´ark Jelasity and Ozalp Babaoglu University protocol, T-Man, for constructing and maintaining a large class of topologies. In the proposed framework in a straightforward, intuitive and flexible manner. At the same time, the T-Man protocol involves only local

197

How Bad Are Overlay Networks? Stephen Cogdon and Ian Wakeman  

E-print Network

-bone [6]. Tree building protocols configure and self-organise the overlay network. Tree building (DVMRP) [4]. The 6-bone is an experimental network for testing IPv6 [5]. The X-bone is an experimental control protocol (TBCP) is a constrained tree building technique [7] signifying that the number

Haddadi, Hamed

198

BWR pipe crack and weld clad overlay studies  

SciTech Connect

This paper presents results on (a) the influence of simulated BWR environments and temperature on the intergranular-stress-corrosion cracking (IGSCC) susceptibility of sensitized stainless steels (SS), (b) the stress-corrosion susceptibility of alternative piping materials, (c) analysis of field components to assess the effectiveness of in-service inspection techniques and the in-reactor performance of weld overlay repairs, and (d) finite-element analyses and experimental measurement of residual stresses in weldments with weld overlays. Fracture-mechanics crack-growth data are presented to confirm correlations between the critical corrosion potentials required to inhibit IGSCC and the level of impurities in the environment. Slow-strain-rate tests show that very low levels of impurities (25 ppb of sulfate) can produce suseptibility to transgranular-stress-corrosion cracking (TGSCC) in Type 316NG SS and that nitrogen levels is SS above 0.1 wt. % appear to increase susceptibility to TGSCC. Preliminary results on a German Type 347NG SS suggest that it is at least as resistant to TGSCC in impurity environments as Type 316NG SS. Measurements on overlay weldments removed from the Hatch-2 reactor confirm that compressive residual stresses are produced on the inner surface of the weldments by the overlay.

Shack, W.J.; Kassner, T.F.; Maiya, P.S.; Park, J.Y.; Ruther, W.E.; Rybicki, E.F.

1985-10-01

199

State involvement in and use of LANDSAT technology  

NASA Technical Reports Server (NTRS)

The background of state involvement in LANDSAT systems planning and the status of state LANDSAT use are reviewed. Major recommendations on data continuity; frequency and pattern of observation; state representation in program management; pointable sensors for a fully operational system; data processing systems; data pricing; data copyright; data archival; and technology transfer are highlighted. Plans of the government regarding the LANDSAT system are reflected in the FY-1982 budget process are examined.

Tessar, P. A.

1981-01-01

200

Use of LANDSAT data to assess waterfowl habitat quality  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. The capability of mapping ponds over a very large area was demonstrated, with multidate, multiframe LANDSAT imagery. A small double sample of aircraft data made it possible to adjust a LANDSAT large area census. Terrain classification was improved by using multitemporal LANDSAT data. Waterfowl production was estimated, using remotely determined pond data, in conjunction with FWS estimates of breeding population. Relative waterfowl habitat quality was characterized on a section by section basis.

Colwell, J. E.; Gilmer, D. S. (principal investigators); Work, E. A., Jr.; Rebel, D. L.; Roller, N. E. G.

1978-01-01

201

Market-Based Self-Optimization for Autonomic Service Overlay Networks  

E-print Network

1 Market-Based Self-Optimization for Autonomic Service Overlay Networks Weihong Wang, Baochun Li, overlay nodes can be programmed to self-organize and self-manage the net- work. To achieve the highest performance within a service overlay, they are further expected to self-optimize the network, by cooperatively

Li, Baochun

202

Overlay accuracy of EUV1 using compensation method for nonflatness of mask  

Microsoft Academic Search

Two EUVL masks were made using the compensation method for nonflatness of a mask; and the EUV1 was used to evaluate the resulting overlay accuracy. For the same mask, the reproducibility of the intra-field overlay errors was better than 1 nm (3sigma) without linear components; and that of the flatness was better than 20 nm PV. In contrast, the overlay

Yuusuke Tanaka; Takashi Kamo; Kazuya Ota; Hiroyuki Tanaka; Osamu Suga; Masamitsu Itoh; Shusuke Yoshitake

2011-01-01

203

Characterizing lens distortion to overlay accuracy by using fine measurement pattern  

Microsoft Academic Search

Previous work has shown that the lens distortion will contribute significantly to overlay error. Since the resolution has gone below 0.18 micrometers with 70 nm overlay tolerance, the lens aberration plays a more important role in the tolerance budget. Originally, the line size of overlay measurement target is about 3 micrometers , which is much larger than the circuit dimensions.

Ron Chu; Chungwei Hsu; Tsu-Wen Hwang

1999-01-01

204

Effects of illumination wavelength on the accuracy of optical overlay metrology  

Microsoft Academic Search

As the integration density in the manufacturing of IC's increases and tighter design rules are implemented, the accuracy of overlay in the photolithography process is becoming all the more important. Consequently, investigation and characterization of the accuracy (as well as precision) of the overlay measurement are being required to insure that the overlay metrology tool qualifies for the new technologies.

Jae-Seong Han; Hak Kim; Jeong-Lim Nam; Min-Seog Han; Soon-Kwon Lim; Shimon D. Yanowitz; Nigel P. Smith; Andrew M. Smout

1997-01-01

205

Landsat-1 and Landsat-2 evaluation report, 23 January 1975 to 23 April 1975  

NASA Technical Reports Server (NTRS)

A description of the work accomplished with the Landsat-1 and Landsat-2 satellites during the period 23 Jan. - 23 Apr. 1975 was presented. The following information was given for each satellite: operational summary, orbital parameters, power subsystem, attitude control subsystem, command/clock subsystem, telemetry subsystem, orbit adjust subsystem, magnetic moment compensating assembly, unified S-band/premodulation processor, electrical interface subsystem, thermal subsystem, narrowband tape recorders, wideband telemetry subsystem, attitude measurement sensor, wideband video tape recorders, return beam vidicon, multispectral scanner subsystem, and data collection subsystem.

1975-01-01

206

LANDSAT: Non-US standard catalog, 1-31 January 1976. [LANDSAT imagery for  

NASA Technical Reports Server (NTRS)

Information regarding the availability of LANDSAT imagery processed and input to the data files by the NASA Data Processing Facility is published on a monthly basis. The U.S. Standard Catalog includes imagery covering the continental United States, Alaska and Hawaii. The Non-U.S. Standard Catalog identifies all the remaining coverage. Sections 1 and 2 describe the contents and format for the catalogs and the associated microfilm. Section 3 provides a cross-reference defining the beginning and ending dates for LANDSAT cycles.

1976-01-01

207

LANDSAT: Non-US standard catalog no. N-36. [LANDSAT imagery for August, 1975  

NASA Technical Reports Server (NTRS)

Information regarding the availability of LANDSAT imagery processed and input to the data files by the NASA Data Processing Facility is published on a monthly basis. The U.S. Standard Catalog includes imagery covering the continental United States, Alaska, and Hawaii. The Non-U.S. Standard Catalog identifies all the remaining coverage. Sections 1 and 2 describe the contents and format for the catalogs and the associated microfilm. Section 3 provides a cross reference defining the beginning and ending dates for LANDSAT cycles.

1975-01-01

208

SRTM Perspective with Landsat Virgin Islands, Carribean  

NASA Technical Reports Server (NTRS)

St. Thomas, St. John, Tortola, and Virgin Gorda are the four main islands (front to back) of this east-looking view of the U.S. Virgin Islands and British Virgin Islands, along the northeast perimeter of the Caribbean Sea. For this view, a nearly cloud-free Landsat image was draped over elevation data from the Shuttle Radar Topography Mission (SRTM), and shading derived from the SRTM data was added to enhance the topographic expression. Elevation is shown with 1.5x scaled vertical exaggeration. Coral reefs fringe the islands in many locations and appear as very light shades of blue. Tropical vegetation appears green, and developed areas appear in shades of brown and white.

As in much of the world, topography is the primary factor in the pattern of land use development in the Virgin Islands. Topography across most of the islands is quite rugged, and although the steep slopes create a scenic setting, they crowd most development into the small areas of low relief terrain, generally along the shoreline. The topographic pattern also affects water supply, wastewater disposal, landfill locations, road construction, and most other features of the development infrastructure. Topography also defines the natural drainage pattern, which is the major consideration in anticipating tropical storm water runoff dangers, as well as the dangers of heightened sediment impacts upon the adjacent coral reefs.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and substantially helps in analyzing the large and growing Landsat image archive.

Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency of the U.S. Department of Defense, and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C.

Size: 94.7 kilometers (58.7 miles) view distance, 29.2 kilometers (18.1 miles) view width Location: 18.25 degrees North latitude, 64.75 degrees West longitude Orientation: Looking EasT Image Data: Landsat Bands 1,2+4, 3 as blue, green, red, respectively Original Data Resolution: SRTM and Landsat 30 meters (99 feet) Date Acquired: February 2000 (SRTM), January 21, 1985 (Landsat)

2003-01-01

209

Anaglyph with Landsat Virgin Islands, Caribbean  

NASA Technical Reports Server (NTRS)

St. Thomas, St. John, Tortola, and Virgin Gorda are the four main islands (lower left to upper right) of this map-view anaglyph of the U.S. Virgin Islands and British Virgin Islands, along the northeast perimeter of the Caribbean Sea. For this view, a nearly cloud-free Landsat image was draped over elevation data from the Shuttle Radar Topography Mission (SRTM), and shading derived from the SRTM data was added to enhance the topographic expression. Coral reefs fringe the islands in many locations and appear as bright patterns in near-shore waters. Tropical vegetation appears fairly dark with smooth tones, as compared to the brighter speckled patterns of towns and other developments.

As in much of the world, topography is the primary factor in the pattern of land use development in the Virgin Islands. Topography across most of the islands is quite rugged, and although the steep slopes create a scenic setting, they crowd most development into the small areas of low relief terrain, generally along the shoreline. The topographic pattern also affects water supply, wastewater disposal, landfill locations, road construction, and most other features of the development infrastructure. Topography also defines the natural drainage pattern, which is the major consideration in anticipating tropical storm water runoff dangers, as well as the dangers of heightened sediment impacts upon the adjacent coral reefs.

Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and substantially helps in analyzing the large and growing Landsat image archive.

Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency of the U.S. Department of Defense, and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C.

Size: 79.9 by 48.6 kilometers (49.9 by 30.1 miles) Location: 18.25 degrees North latitude, 64.75 degrees West longitude Orientation: North-Northeast toward the top Image Data: Landsat Band 1 with SRTM shading Original Data Resolution: SRTM and Landsat 30 meters (99 feet) Date Acquired: February 2000 (SRTM), January 21, 1985 (Landsat)

2003-01-01

210

SRTM Radar - Landsat Image Comparison, Patagonia, Argentina  

NASA Technical Reports Server (NTRS)

In addition to an elevation model of most of Earth'slandmass, the Shuttle Radar Topography Mission will produce C-band radar imagery of the same area. This imagery is essentially a 10-day snapshot view of the Earth, as observed with 5.8 centimeter wavelength radar signals that were transmitted from the Shuttle, reflected by the Earth, and then recorded on the Shuttle. This six-image mosaic shows two examples of SRTM radar images (center) with comparisons to images acquired by the Landsat 7 satellite in the visible wavelengths (left) and an infrared wavelength (right). Both sets of images show lava flows in northern Patagonia, Argentina. In each case, the lava flows are relatively young compared to the surrounding rock formations.

In visible light (left) image brightness corresponds to mineral chemistry and -- as expected -- both lava flows appear dark. Generally, the upper flow sits atop much lighter bedrock, providing good contrast and making the edges of the flow distinct. However, the lower flow borders some rocks that are similarly dark, and the flow boundaries are somewhat obscured. Meanwhile, in the radar images (center), image brightness corresponds to surface roughness (and topographic orientation) and substantial differences between the flows are visible. Much of the top flow appears dark, meaning it is fairly smooth. Consequently, it forms little or no contrast with the smooth and dark surrounding bedrock and thus virtually vanishes from view. However, the lower flow appears rough and bright and mostly forms good contrast with adjacent bedrock such that the flow is locally more distinct here than in the visible Landsat view. For further comparison, infrared Landsat images (right) again show image brightnesses related to mineral chemistry, but the lava flows appear lighter than in the visible wavelengths. Consequently, the lower lava flow becomes fairly obscure among the various surrounding rocks, just as the upper flow did in the radar image. The various differences among all of these images illustrate the importance of illumination wavelength in image interpretation.

The Landsat 7 Thematic Mapper images used here were provided to the SRTM project by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center, Sioux Falls, South Dakota.

The radar images shown here were acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise,Washington, DC.

Size (top set): 21.3 kilometers (13.2 miles) x 25.0 kilometers (15.5 miles) Size (bottom set): 44.1 kilometers (27.3 miles) x 56.0 kilometers (34.7 miles) Location: 41.5 deg. South lat., 69 deg. West lon. Orientation: North toward upper left (top set), North toward upper right (bottom set) Image Data: Landsat bands 1,2,3 (left); SRTM Radar (middle); Landsat band 7 (right) Date Acquired: February 19, 2000 (SRTM), January 22, 2000 (Landsat)

2000-01-01

211

LANDSAT: Non-US standard catalog. [LANDSAT imagery for August 1977  

NASA Technical Reports Server (NTRS)

The non-U. S. Standard Catalog lists non-U. S. imagery acquired by LANDSAT 1 and 2 which has been processed and input to the data files during the referenced month. Data, such as date acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found is also given.

1977-01-01

212

LANDSAT Non-US standard catalog, 1-31 December 1975. [LANDSAT imagery for December 1975  

NASA Technical Reports Server (NTRS)

The Non-U.S. Standard Catalog lists Non-U.S. imagery acquired by LANDSAT 1 and 2 which has been processed and input to the data files during the referenced month. Data, such as date acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found is also given.

1975-01-01

213

LANDSAT US standard catalog, 1 October - 31 October 1977. [LANDSAT imagery for Oktober 1977  

NASA Technical Reports Server (NTRS)

The U. S. standard catalog lists U. S. imagery acquired by LANDSAT 1 and 2 which has been processed and input to the data files during the referenced month. Data, such as date acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found is also given.

1977-01-01

214

Toward multidisciplinary use of LANDSAT: Interfacing computerized LANDSAT analysis systems with geographic information systems  

NASA Technical Reports Server (NTRS)

The LANDSAT-geographic information system (GIS) interface must summarize the results of the LANDSAT classification over the same cells that serve as geographic referencing units for the GIS, and output these summaries on a cell-by-cell basis in a form that is readable by the input routines of the GIS. The ZONAL interface for cell-oriented systems consists of two primary programs. The PIXCEL program scans the grid of cells and outputs a channel of pixels. Each pixel contains not the reflectance values but the identifier of the cell in which the center of the pixel is located. This file of pixelized cells along with the results of a pixel-by-pixel classification of the scene produced by the LANDSAT analysis system are input to the CELSUM program which then outputs a cell-by-cell summary formatted according to the requirements of the host GIS. Cross-correlation of the LANDSAT layer with the other layers in the data base is accomplished with the analysis and display facilities of the GIS.

Myers, W. L.

1981-01-01

215

LANDSAT-1 and LANDSAT-2 flight evaluation report, 23 January - 23 April 1977  

NASA Technical Reports Server (NTRS)

The LANDSAT operations from launch through orbital instrument observations are reviewed. Orbital parameters, power subsystem, attitude control subsystem, and command/clock subsystem are discussed. Other subsystems are also considered, such as telemetry, orbit adjust, electrical interface, thermal, wideband telemetry, multispectral scanner, and data collection.

1977-01-01

216

Landsat: The Backbone for Mapping and Monitoring Global Ecological Trends  

NASA Astrophysics Data System (ADS)

Long-term ecological monitoring requires consistent observation of key variables, long-term measurement continuity, and open and affordable access to measurements. The Landsat series of Earth observation missions uniquely meet those criteria, and Landsat's 30m-observation scale permits the detection and differentiation of natural versus human-caused land change. Landsat is the longest and most comprehensive record of the state of the global land surface in existence. No other high-resolution satellite program is either capable or committed to the systematic monitoring of global scale human and natural land change. Beginning with Landsat 1 in 1972, six Landsat missions have continuously recorded images of the Earth. As we near the fortieth anniversary of Landsat, we now have an archive of millions of repetitive images of the Earth with multispectral properties suited to assessing both biotic and abiotic conditions and at a scale appropriate for resource management. The U.S. Geological Survey's (USGS) Earth Resources Observations Systems (EROS) Landsat archive contains nearly three million scenes and all are available to users at no cost. Furthermore, the entire Landsat record, Landsats 1-7, is now calibrated to a common radiometric standard and the majority of the data are orthorectified - enabling immediate assessment of long-term ecological conditions and land change. Landsats 5 and 7 continue to collect imagery and together they provide the potential to cover a significant portion of the Earth's land surfaces every eight days. Both of these missions now use a long-term acquisition plan designed to improve the collection of seasonal global coverage. Furthermore, recent agreements with international Landsat receiving stations are bringing previously inaccessible contemporary Landsat 5 data into the EROS archive. The amount of global coverage being acquired annually is the highest level in the history of the Landsat program. The EROS global historical archive is rapidly expanding because of the addition of 1972-present Landsat holdings from ground stations worldwide. More than three million Landsat scenes not currently found in the EROS archive exist in archives around the world and many of these data are at risk due to aging storage media and inadequate preservation practices. The repatriation of these data into the EROS archive will potentially double the number of no-cost Landsat scenes available to users. The uncertainty of future Landsat missions has challenged operational monitoring of ecological systems. However, that may be changing. The Landsat Data Continuity Mission (LDCM) being developed by NASA and the USGS is slated for a December 2012 launch. LDCM (which will be renamed Landsat 8 following launch) will use new imaging technology to provide improved multispectral measurements, and offers additional spectral bands and increased daily imaging capacity. While missions beyond LDCM are uncertain, the President's Fiscal Year 2012 budget requests funds for the planning and development of Landsats 9 and 10, and includes language that will make Landsat an operational program - ending the decades of uncertainty.

Loveland, T. R.

2011-12-01

217

Lake water quality mapping from Landsat  

NASA Technical Reports Server (NTRS)

In the project described remote sensing was used to check the quality of lake waters. The lakes of three Landsat scenes were mapped with the Bendix MDAS multispectral analysis system. From the MDAS color coded maps, the lake with the worst algae problem was easily located. The lake was closely checked, and the presence of 100 cows in the springs which fed the lake could be identified as the pollution source. The laboratory and field work involved in the lake classification project is described.

Scherz, J. P.

1977-01-01

218

Background reflectance effects in Landsat data.  

PubMed

A regression analysis was performed on Landsat MSS data to investigate the dependence of object radiance on the radiance of adjacent areas. The object radiance is increased by a path radiance component attributed to forward scattering in the atmosphere after reflection of solar radiation from the object background. Inclusion of average radiance of a few concentric rings with object reflectance in the regression model for satellite-measured radiance improves the least-squares fit at all sites tested. Multiple regression analysis indicates that radiance of an object is significantly affected by reflectance of background objects up to 500 m away. PMID:20401017

Dana, R W

1982-11-15

219

California coastal processes study, LANDSAT 2  

NASA Technical Reports Server (NTRS)

The authors have identified the following significant results. By using suspended sediments as tracers, objectives were met by qualitative definition of the nearshore circulation along the entire coast of California with special study sites at Humboldt Bay, the mouth of the Russian River, San Francisco Bay, Monterey Bay, and the Santa Barbara Channel. Although LANDSAT primarily imaged fines and silts in the surface waters, the distribution of sediments allowed an examination of upwelling, convergences and coastal erosion and deposition. In Monterey Bay and Humboldt Bay, these coastal phenomena were used to trace seasonal trends in surface currents.

Pirie, D. M.; Steller, D. D. (principal investigators)

1977-01-01

220

Operational alternatives for LANDSAT in California  

NASA Technical Reports Server (NTRS)

Data integration is defined and examined as the means of promoting data sharing among the various governmental and private geobased information systems in California. Elements of vertical integration considered included technical factors (such as resolution and classification) and institutional factors (such as organizational control, and legal and political barriers). Attempts are made to fit the theoretical elements of vertical integration into a meaningful structure for looking at the problem from a statewide focus. Both manual (mapped) and machine readable data systems are included. Special attention is given to LANDSAT imagery because of its strong potential for integrated use and its primary in the California Integrated Remote Sensing System program.

Wilson, P.; Gialdini, M. J.

1981-01-01

221

Monitoring wetlands change using LANDSAT data  

NASA Technical Reports Server (NTRS)

A wetlands monitoring study was initiated as part of Delaware's LANDSAT applications demonstration project. Classifications of digital data are conducted in an effort to determine the location and acreage of wetlands loss or gain, species conversion, and application for the inventory and typing of freshwater wetlands. A multi-seasonal approach is employed to compare data from two different years. Unsupervised classifications were conducted for two of the four dates examined. Initial results indicate the multi-seasonal approach allows much better separation of wetland types for both tidal and non-tidal wetlands than either season alone. Change detection is possible but generally misses the small acreages now impacted by man.

Hardin, D. L.

1981-01-01

222

Ground data handling for LANDSAT-D  

NASA Technical Reports Server (NTRS)

The present plans for the LANDSAT D ground data handling are described in relationship to the mission objectives and the planned spacecraft system. The end to end data system is presented with particular emphasis on the data handling plans for the new instrument, the Thematic Mapper. This instrument generates ten times the amount of data per scene as the present Multispectral Scanner, and this resulting data rate and volume are discussed as well as possible new data techniques to handle them such as image compression.

Lynch, T. J.

1976-01-01

223

LANDSAT 4 band 6 data evaluation  

NASA Technical Reports Server (NTRS)

Satellite data collected over Lake Ontario were processed to observed surface temperature values. This involved computing apparent radiance values for each point where surface temperatures were known from averaged digital count values. These radiance values were then converted by using the LOWTRAN 5A atmospheric propagation model. This model was modified by incorporating a spectral response function for the LANDSAT band 6 sensors. A downwelled radiance term derived from LOWTRAN was included to account for reflected sky radiance. A blackbody equivalent source radiance was computed. Measured temperatures were plotted against the predicted temperature. The RMS error between the data sets is 0.51K.

1983-01-01

224

Monitoring Forest Succession Using Multitemporal Landsat Images: Factors of Uncertainties  

Microsoft Academic Search

This study evaluates uncertainty factors in using multitemporal Landsat images for subtle change detection, including atmosphere, topography, phenology, sun and view angles. The study is based on monitoring forest succession with a set of multiple Landsat TM\\/ETM+ images spanning 15 years over the H. J. Andrews Experimental Forest in the Western Cascades of Oregon. The algorithms for removing atmospheric effects

C. Song

2004-01-01

225

LANDSAT US standard catalog, 1-31 March 1976  

NASA Technical Reports Server (NTRS)

The U.S. Standard Catalog lists U.S. imagery acquired by LANDSAT 1 and LANDSAT 2 which has been processed and input to the data files during the referenced month. Data, such as date acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found is also given.

1976-01-01

226

LANDSAT 1 cumulative US standard catalog, 1976/1977  

NASA Technical Reports Server (NTRS)

The LANDSAT 1 U.S. Cumulative Catalog lists U.S. imagery acquired by LANDSAT 1 which has been processed and input to the data files during the referenced year. Data, such as data acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found are also given.

1977-01-01

227

LANDSAT-4 World Reference System (WRS) users guide  

NASA Technical Reports Server (NTRS)

A functional description of the new LANDSAT-4 World Reference System (WRS) with an overview of the main orbital parameters and instrument coverages is presented to provide the data user with the primary information required to understand LANDSAT-4 orbital characteristics, to effectively use the WRS indexing scheme, and to request specific geographic coverage on the desired observation dates.

1982-01-01

228

LANDSAT US standard catalog, 1-30 November 1976  

NASA Technical Reports Server (NTRS)

The U.S. Standard Catalog lists U.S. imagery acquired by LANDSAT 1 and LANDSAT 2 which las been processed and input to the data files during the referenced month. Data, such as date acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found is also given.

1976-01-01

229

LANDSAT US standard catalog, 1-31 May 1976  

NASA Technical Reports Server (NTRS)

The U.S. standard catalog lists U.S. imagery acquired by LANDSAT 1 and LANDSAT 2 which has been processed and input to the data files during the referenced month. Data, such as date acquired, cloud cover and image quality are given for each scene. The microfilm and frame on which the scene may be found is also given.

1976-01-01

230

Snow Scene of the Lake Erie Area from Landsat.  

ERIC Educational Resources Information Center

A snow-covered landscape as viewed from Landsat offers some intriguing possibilities for interpretation of various earth features that are difficult to discern on imagery taken at other times of the year. This Landsat image can be analyzed and studied by college- level geography students. (AM)

Harnapp, Vern

1982-01-01

231

Framework for exploring the interaction between design rules and overlay control  

NASA Astrophysics Data System (ADS)

Overlay control is becoming increasingly more important with the scaling of technology. It has become even more critical and more challenging with the move toward multiple-patterning lithography, where overlay translates into CD variability. Design rules and overlay have strong interaction and can have a considerable impact on the design area, yield, and performance. We study this interaction and evaluate the overall design impact of rules, overlay characteristics, and overlay control options. For this purpose, we developed a model for yield loss from overlay that considers overlay residue after correction and the breakdown between field-to-field and within-field overlay; the model is then incorporated into a general design-rule evaluation framework to study the overlay/design interaction. The framework can be employed to optimize design rules and more accurately project overlay-control requirements of the manufacturing process. The framework is used to explore the design impact of litho-etch litho-etch double-patterning rules and poly line-end extension rule defined between poly and active layer for different overlay characteristics (i.e., within-field versus field-to-field overlay) and different overlay models at the 14-nm node. Interesting conclusions can be drawn from our results. For example, one result shows that increasing the minimum mask-overlap length by 1 nm would allow the use of a third-order wafer/sixth-order field-level overlay model instead of a sixth-order wafer/sixth-order field-level model with negligible impact on design.

Ghaida, Rani S.; Gupta, Mukul; Gupta, Puneet

2013-07-01

232

On-demand Overlay Networks for Large Scientific Data Transfers  

SciTech Connect

Large scale scientific data transfers are central to scientific processes. Data from large experimental facilities have to be moved to local institutions for analysis or often data needs to be moved between local clusters and large supercomputing centers. In this paper, we propose and evaluate a network overlay architecture to enable highthroughput, on-demand, coordinated data transfers over wide-area networks. Our work leverages Phoebus and On-demand Secure Circuits and AdvanceReservation System (OSCARS) to provide high performance wide-area network connections. OSCARS enables dynamic provisioning of network paths with guaranteed bandwidth and Phoebus enables the coordination and effective utilization of the OSCARS network paths. Our evaluation shows that this approach leads to improved end-to-end data transfer throughput with minimal overheads. The achievedthroughput using our overlay was limited only by the ability of the end hosts to sink the data.

Ramakrishnan, Lavanya; Guok, Chin; Jackson, Keith; Kissel, Ezra; Swany, D. Martin; Agarwal, Deborah

2009-10-12

233

Flutter Analysis of the Shuttle Tile Overlay Repair Concept  

NASA Technical Reports Server (NTRS)

The Space Shuttle tile overlay repair concept, developed at the NASA Johnson Space Center, is designed for on-orbit installation over an area of damaged tile to permit safe re-entry. The thin flexible plate is placed over the damaged area and secured to tile at discreet points around its perimeter. A series of flutter analyses were performed to determine if the onset of flutter met the required safety margins. Normal vibration modes of the panel, obtained from a simplified structural analysis of the installed concept, were combined with a series of aerodynamic analyses of increasing levels of fidelity in terms of modeling the flow physics to determine the onset of flutter. Results from these analyses indicate that it is unlikely that the overlay installed at body point 1800 will flutter during re-entry.

Bey, Kim S.; Scott, Robert C.; Bartels, Robert E.; Waters, William A.; Chen, Roger

2007-01-01

234

A finite element overlay technique for modeling pinned composite joints  

NASA Technical Reports Server (NTRS)

A finite element technique using overlaid plane stress elements is presented for modeling a pinned composite joint. The technique allows for discrete modeling of the pin and web regions of the joint in a two-dimensional (2-D) finite element analysis. Thus, predictive capability is substantially increased without the added complexity of a three-dimensional (3-D) analysis. The overlay technique requires a thorough evaluation of the model constraints between the joint components. Bearing panels are used to account for a reduced compressive modulus under bearing loads. Application of the plane stress overlay technique to the Filament Wound Case (FWC) Program is discussed. The experimental approach to determine bearing panel moduli using a double lap shear test is detailed, and finite element results are correlated with full-scale FWC joint test results.

Colvin, G. E.; Adams, D. S.

1986-01-01

235

On the overlay of CDMA 1xEVDO system  

Microsoft Academic Search

In this paper the impact of the overlay of CDMA2000 1x-EVDO and CDMA2000 cellular systems in terms of throughput is investigated. Currently, the 3G cellular systems furthermore to provide only voice services are focusing to offer a variety of data applications such as VoIP, video, telephony, wireless gaming, and push-to-talk (PTT), along with a high demand of downlink intensive applications.

José Antonio Avendaño-Osorio; Hebert Harif Ortiz-Flores; Josefina Castañeda-Camacho

2009-01-01

236

Interface Chemistry and Physics of SEMICONDUCTOR:MOLECULAR Overlayer Systems  

Microsoft Academic Search

A number of semiconductor: molecular overlayer systems have been studied with the focus being on photoelectrochromic devices and semiconductor surface passivation. The topics are discussed in the dissertation in that order. Spectroscopic (UV-VIS absorption and Raman scattering) and electrochemical techniques were used to characterize the photochromic behavior of thin Prussian Blue films grown on partially reduced single crystal SrTiO_3 wafers.

John Paul Ziegler

1988-01-01

237

Shielding turbine blades from cvitation: Experiments with polymer overlays  

SciTech Connect

Cavitation damage to hydroelectric machinery produces one of the most prevalent maintenance problems at any hydro plant. Damage to the turbine runner blades, draft tube liner and discharge ring, and sometimes even the runner hub can require extensive welding repair. Typically, each unit develops its own cavitation characteristics that continue throughout the life of the machine. The traditional cavitation repair method is to gouge out the damaged material, then refill the void with a stainless steel. This method is costly and time-consuming, may cause blade distortion, and may result in galvanic corrosion when the stainless steel is applied to carbon steel base materials. What's more, this gouging and filling at temperatures between 2,200 and 2.300[degrees]F within a tenth of a square inch may cause residual stresses in the parent material. One strategy for limiting cavitation effects on turbine components is to overlay the original material with a protective layer. This protective coating will absorb the cavitation load, or at least a portion of it, thus limiting further damage to repaired areas. Typically, an overlay consists of a 1/32-inch or 1/16-inch layer of polymer material (either epoxies or ceramics) and a thin adhesive that bonds the polymer to the turbine steel. A cavitation-induced shock (energy) wave propagates through the polymer material and either reflects or transmits into the steel. (The relative acoustic impedances of the two materials determine whether the shock wave travels into the turbine steel or reflects back through the polymer.) For the overlay to be effective, the shock wave must be reflected, attenuated, or dispersed. typical overlay materials do not reflect, attenuate, or disperse the cavitation shock wave. Polycarbonates, with their unique energy dissipation capabilities, are a good candidate for a protective turbine blade coating.

Armentrout, T.B. (Army Corps of Engineers, The Dalles, OR (United States))

1993-05-01

238

Advances in process overlay on 300-mm wafers  

Microsoft Academic Search

Overlay budgets are getting tighter within 300 mm volume production and as a consequence the process effects on alignment and off-line metrology becomes more important. In a short loop experiment, with cleared reference marks in each image field, the isolated effect of processing was measured with a sub-nanometer accuracy. The examined processes are Shallow Trench Isolation (STI), Tungsten-Chemical Mechanical Processing

Jens Staecker; Stefanie Arendt; Karl Schumacher; Evert C. Mos; Richard J. van Haren; Maurits van der Schaar; Remi Edart; Wolfgang Demmerle; Hoite Tolsma

2002-01-01

239

Prediction of Reflection Cracking in Hot Mix Asphalt Overlays  

E-print Network

for HMA overlay with reinforcing geosynthetic over jointed concrete pavement in wet-freeze zone (New York, New York) ??????????????????????????? 258 5.12 The comparision between field and predicted results for LMH severity distress (AC over AC... pavement structure, Wet-Freeze climatic zone) ???????? 260 5.13 The comparision between field and predicted results for LMH severity distress (AC over JPC pavement structure, Wet-Freeze climatic zone) ??????? 261 5.14 The comparision between field...

Tsai, Fang-Ling

2011-02-22

240

Segment-sending Schedule in Data-driven Overlay Network  

Microsoft Academic Search

Data-driven overlay network is suitable for live-event streaming, because it can provide relatively-continuous streaming even in dynamic environment. In terms of improving streaming quality, prior work covered membership management, buffer map exchange, segment requesting schedule, etc. In this paper, we address the problem of segment-sending schedule on the segment-providing node, which may also affect the streaming quality. The schedule methods

Dan Li; Yong Cui; Ke Xu; Jianping Wu

2006-01-01

241

Fireflies: scalable support for intrusion-tolerant network overlays  

Microsoft Academic Search

This paper describes and evaluates Fireflies, a scalable pro- tocol for supporting intrusion-tolerant network overlays.1 While such a protocol cannot distinguish Byzantine nodes from correct nodes in general, Fireflies provides correct nodes with a reasonably current view of which nodes are live, as well as a pseudo-random mesh for communication. The amount of data sent by correct nodes grows linearly

Håvard D. Johansen; André Allavena; Robbert Van Renesse

2006-01-01

242

SureMail: Notification Overlay for Email Reliability  

Microsoft Academic Search

We consider the problem of silent email loss in the Internet. Some recent studies have reported loss rates of 0.5-1%, which indicates that the problem is significant, especially since email loss can impose a high cost. We present SureMail, a system designed to address the silent email loss problem. SureMail augments the existing SMTP-based email system with a notification overlay

Sharad Agarwal; Venkata N. Padmanabhan; Dilip A. Joseph

2005-01-01

243

Advancements of diffraction-based overlay metrology for double patterning  

NASA Astrophysics Data System (ADS)

As the dimensions of integrated circuit continue to shrink, diffraction based overlay (DBO) technologies have been developed to address the tighter overlay control challenges. Previously data of high accuracy and high precision were reported for litho-etch-litho-etch double patterning (DP) process using normal incidence spectroscopic reflectometry on specially designed targets composed of 1D gratings in x and y directions. Two measurement methods, empirical algorithm (eDBO) using four pads per direction (2x4 target) and modeling based algorithm (mDBO) using two pads per direction (2x2 target) were performed. In this work, we apply DBO techniques to measure overlay errors for a different DP process, litho-freeze-litho-etch process. We explore the possibility of further reducing number of pads in a DBO target using mDBO. For standard targets composed of 1D gratings, we reported results for eDBO 2x4 targets, mDBO 2x2 targets, and mDBO 2x1 target. The results of all three types of targets are comparable in terms of accuracy, dynamic precision, and TIS. TMU (not including tool matching) is less than 0.1nm. In addition, we investigated the possibility of measuring overlay with one single pad that contains 2D gratings. We achieved good correlation to blossom measurements. TMU (not including tool matching) is ~ 0.2nm. To our best knowledge, this is the first time that DBO results are reported on a single pad. eDBO allows quick recipe setup but takes more space and measurement time. Although mDBO needs details of optical properties and modeling, it offers smaller total target size and much faster throughput, which is important in high volume manufacturing environment.

Li, Jie; Kritsun, Oleg; Liu, Yongdong; Dasari, Prasad; Weher, Ulrich; Volkman, Catherine; Mazur, Martin; Hu, Jiangtao

2011-03-01

244

Sesso Especial: Landsat-8: Planos e Perspectivas (Landsat-8: Plans and Perspectives) Coordenador: Michael A. Wulder (Canadian Forest Service, Canad)  

E-print Network

. Since the beginning of the Landsat program NASA has strived to ensure the continuity of measures while atividades globalmente. Desde o início do programa Landsat, a NASA tem se esforçado para garantir and Sensors Jeffrey G. Masek (NASA Goddard Space Flight Center, USA) 10:50 Seeing the Future: Applications

245

LANDSAT: US standard catalog, 1 February 1977 - 28 February 1977. [LANDSAT imagery for the month of February 1977  

NASA Technical Reports Server (NTRS)

The U.S. Standard Catalog lists U.S. imagery acquired by LANDSAT 1 and LANDSAT 2 which has been processed and input to the data files during the referenced month. Data, such as data acquired, cloud cover and image quality are given for each scene. The microfilm roll and frame on which the scene may be found is also given.

1977-01-01

246

An Overlapping Structured P2P for REIK Overlay Network  

NASA Astrophysics Data System (ADS)

REIK is based on a ring which embedded an inverse Kautz digraph, to enable multi-path P2P routing. It has the constant degree and the logarithmic diameter DHT scheme with constant congestion and Byzantine fault tolerance. However, REIK did not consider the interconnection of many independent smaller networks. In this paper, we propose a new approach to build overlay network, OLS-REIK which is an overlapping structured P2P for REIK overlay network. It is a more flexible interconnecting different REIK network. Peers can belong to several rings, allowing this interconnection. By connecting smaller structured overlay networks in an unstructured way, it provides a cost effective alternative to hierarchical structured P2P systems requiring costly merging. Routing of lookup messages is performed as in REIK within one ring, but a peer belonging to several rings forwards the request to the different rings it belongs to. Furthermore a small number of across point is enough to ensure a high exhaustiveness level.

Liu, Wenjun; Song, Jingjing; Yu, Jiguo

247

Impact of chuck flatness on wafer distortion and stepper overlay  

NASA Astrophysics Data System (ADS)

Overlay accuracy is known as one of the most important subjects for ULSI device production. Significant contributions such as alignment accuracy and mask distortions are well known. By breaking the 100 nm range on overlay accuracy a number of influences have to take into account, which were usually neglected for relaxed design rules. One of these influences to the overlay is directly related to wafer distortions induced by flatness deviations of wafer chucks. This impact was characterized by investigating the elastic behavior of 4' wafers (525 micrometers thick), fixed on a wafer chuck. Induced elastical deformation due to flatness error of the chuck causes strains and elongations in the wafer surface and therefore wafer distortions. The results obtained by exposure experiments and calculations show that even a point size defect has a 30 mm spreading. Therefore the induced distortions arrives about 100 nm in case of a 3 micrometers flatness irregularity. The final result of the investigations induces that the flatness differences between different wafer chucks or steppers should be smaller than 1 micrometers for design rules below quarter micron.

Simon, Klaus; Scheunemann, H.-U.; Huber, Hans L.; Gabeli, F.

1993-06-01

248

Hg binding on Pd binary alloys and overlays  

SciTech Connect

The vast majority of the mercury released from coal combustion is elemental mercury. Noble metals such as Pd, Au, Ag, and Cu have been proposed to capture elemental mercury. Density functional theory calculations are carried out to investigate mercury interactions with Pd binary alloys and overlays in addition to pure Pd, Au, Ag, and Cu surfaces using a projected augmented wave method with the Perdew-Wang generalized 0 gradient approximation. It has been determined that Pd has the highest mercury binding energy in comparison to other noble metals. In addition, Pd is found to be the primary surface atom responsible for improving the interaction of mercury with the surface atoms in both Pd binary alloys and overlays. Deposition of Pd overlays on Au and Ag enhance the reactivity of the surface by shifting the d-states of surface atoms up in energy. Strong mercury binding causes a significant overlap between the s- and p-states of Pd and the d-state of Mercury.

Sasmaz, E.; Aboud, S.; Wilcox, J. [Stanford University, Stanford, CA (United States). School of Earth Science

2009-05-15

249

Diffusion Barriers to Increase the Oxidative Life of Overlay Coatings  

NASA Technical Reports Server (NTRS)

Currently, most blades and vanes in the hottest section of aero gas turbine engines require some type of coating for oxidation protection. Newly developed single crystal superalloys have the mechanical potential to operate at increasingly higher component temperatures. However, at these elevated temperatures, coating/substrate interdiffusion can shorten the protective life of the coating. Diffusion barriers between overlay coatings and substrates are being examined to extend the protective life of the coating. A previously- developed finite-difference diffusion model has been modified to predict the oxidative life enhancement due to use of a diffusion barrier. The original diffusion model, designated COSIM, simulates Al diffusion in the coating to the growing oxide scale as well as Al diffusion into the substrate. The COSIM model incorporates an oxide growth and spalling model to provide the rate of Al consumption during cyclic oxidation. Coating failure is predicted when the Al concentration at the coating surface drops to a defined critical level. The modified COSIM model predicts the oxidative life of an overlay coating when a diffusion barrier is present eliminating diffusion of Al from the coating into the substrate. Both the original and the modified diffusion models have been used to predict the effectiveness of a diffusion barrier in extending the protective life of a NiCrAl overlay coating undergoing cyclic oxidation at 1100 C.

Nesbitt, James A.; Lei, Jih-Fen

1999-01-01

250

Network-Aware Overlay Multicast for Large Data Dissemination  

NASA Astrophysics Data System (ADS)

In this paper, we propose a network-aware overlay multicast (NAOM) technique for large data dissemination in a well-managed overlay network. To improve the throughput, NAOM utilizes forward-only hosts; these hosts participate in the overlay network but are not members of the multicast. With the inclusion of the forward-only hosts, data slices can detour bottleneck links and more resources can be used to build efficient multicast trees. Large data are divided into fixed-size slices, and the slices are delivered simultaneously to multicast receivers along the multiple multicast trees. We model the problem of building efficient multicast trees with the inclusion of forward-only hosts. The problem is an NP-hard problem, and we introduce a polynomial time heuristic algorithm. Furthermore, we propose a dynamic scheduling scheme for the transfer of data along the evaluated multicast trees. Our experimental results in a real network environment show an improvement of the throughput but at the cost of additional resource consumption of forward-only nodes.

Lee, Joonbok; Chon, Kilnam

251

LANDSAT-D investigations in snow hydrology  

NASA Technical Reports Server (NTRS)

Work undertaken during the contract and its results are described. Many of the results from this investigation are available in journal or conference proceedings literature - published, accepted for publication, or submitted for publication. For these the reference and the abstract are given. Those results that have not yet been submitted separately for publication are described in detail. Accomplishments during the contract period are summarized as follows: (1) analysis of the snow reflectance characteristics of the LANDSAT Thematic Mapper, including spectral suitability, dynamic range, and spectral resolution; (2) development of a variety of atmospheric models for use with LANDSAT Thematic Mapper data. These include a simple but fast two-stream approximation for inhomogeneous atmospheres over irregular surfaces, and a doubling model for calculation of the angular distribution of spectral radiance at any level in an plane-parallel atmosphere; (3) incorporation of digital elevation data into the atmospheric models and into the analysis of the satellite data; and (4) textural analysis of the spatial distribution of snow cover.

Dozier, J. (principal investigator); Davis, R. E.; Dubayah, R. O.; Frew, J. E.; Li, S.; Marks, D.; Milliff, R. F.; Rousseau, D. D.; Wan, Z. M.

1985-01-01

252

Overlay accuracy of EUV1 using compensation method for nonflatness of mask  

NASA Astrophysics Data System (ADS)

Two EUVL masks were made using the compensation method for nonflatness of a mask; and the EUV1 was used to evaluate the resulting overlay accuracy. For the same mask, the reproducibility of the intra-field overlay errors was better than 1 nm (3?) without linear components; and that of the flatness was better than 20 nm PV. In contrast, the overlay errors were about 3 nm (3?) for the two masks. The main cause of this degradation in overlay accuracy might be the difference in mask flatness (~260 nm PV). Using overlay patterns corrected by the compensation method reduced the overlay errors to about 2.5 nm (3?). Although the compensation method produced only a small change, it definitely improved the intra-field overlay of the EUV1. Furthermore, the EUV1 was used to evaluate the intra-wafer overlay for 23 shots. The single-machine overlay (SMO) was found to be better than 4.5 nm (Mean + 3?nonlinear), and the mix-and-match overlay (MMO) between the EUV1 and an ArF immersion scanner (NSR-S610C) was about 20 nm (Mean + 3?nonlinear). The main cause of the MMO errors might be the nonflatness of the mask and wafer chucks of the EUV1. Thus, the chucks must be made flatter to reduce MMO errors. This work was supported in part by NEDO.

Tanaka, Yuusuke; Kamo, Takashi; Ota, Kazuya; Tanaka, Hiroyuki; Suga, Osamu; Itoh, Masamitsu; Yoshitake, Shusuke

2011-04-01

253

Investigation of radiometric properties of the LANDSAT-4 multispectral scanner  

NASA Technical Reports Server (NTRS)

The radiometric data quality of the LANDSAT 4 multispectral scanner (MSS) was examined using several LANDSAT 4 frames. It was found that LANDSAT 4 MSS produces high-quality data of the caliber experienced with previous LANDSATS. For example, the detector equalization procedure worked well, leaving a residual banding effect of about 0.3 digital counts RMS, close to the theoretical minimum value of quantization error. Nevertheless, artifacts of the data were found, two of which were not experienced in previous MSS data. A low-level coherent noise effect was observed in all bands, with a magnitude of about 0.5 digital counts and a frequency of approximately 28 KHz (representing a wavelength of about 3.6 pixels); a substantial increase in processing complexity would be required to reduce this artifact in the data. Also, a substantial scan-length variation (of up to six pixels) was noted in MSS data when the TM sensor was operating; the LANDSAT 4 correction algorithms being applied routinely by the EROS Data Center to produce a p-type data should remove most of this variation. Between-satellite calibrations were examined in paired LANDSAT 3 and LANDSAT 4 MSS data sets, which were closely matched in acquisition time and place. Radiometric comparisons showed that all bands were highly linear in digital counts, and a well-determined linear transformation between the MSS's was established.

Malila, W. A. (principal investigator); Rice, D. P.

1983-01-01

254

Evaluation of Free-Riding Traffic Problem in Overlay Routing and Its Mitigation Method  

NASA Astrophysics Data System (ADS)

Recent research on overlay networks has revealed that user-perceived network performance could be improved by an overlay routing mechanism. The effectiveness of overlay routing is mainly a result of the policy mismatch between the overlay routing and the underlay IP routing operated by ISPs. However, this policy mismatch causes a “free-riding” traffic problem, which may become harmful to the cost structure of Internet Service Providers. In the present paper, we define the free-riding problem in the overlay routing and evaluate the degree of free-riding traffic to reveal the effect of the problem on ISPs. We introduce a numerical metric to evaluate the degree of the free-riding problem and confirm that most multihop overlay paths that have better performance than the direct path brings the free-riding problem. We also discuss the guidelines for selecting paths that are more effective than the direct path and that mitigate the free-riding problem.

Hasegawa, Go; Hiraoka, Yuichiro; Murata, Masayuki

255

Some spectral and spatial characteristics of LANDSAT data  

NASA Technical Reports Server (NTRS)

Activities are provided for: (1) developing insight into the way in which the LANDSAT MSS produces multispectral data; (2) promoting understanding of what a "pixel" means in a LANDSAT image and the implications of the term "mixed pixel"; (3) explaining the concept of spectral signatures; (4) deriving a simple signature for a class or feature by analysis: of the four band images; (5) understanding the production of false color composites; (6) appreciating the use of color additive techniques; (7) preparing Diazo images; and (8) making quick visual identifications of major land cover types by their characteristic gray tones or colors in LANDSAT images.

1982-01-01

256

Landsat for practical forest type mapping - A test case  

NASA Technical Reports Server (NTRS)

Computer classified Landsat maps are compared with a recent conventional inventory of forest lands in northern Maine. Over the 196,000 hectare area mapped, estimates of the areas of softwood, mixed wood and hardwood forest obtained by a supervised classification of the Landsat data and a standard inventory based on aerial photointerpretation, probability proportional to prediction, field sampling and a standard forest measurement program are found to agree to within 5%. The cost of the Landsat maps is estimated to be $0.065/hectare. It is concluded that satellite techniques are worth developing for forest inventories, although they are not yet refined enough to be incorporated into current practical inventories.

Bryant, E.; Dodge, A. G., Jr.; Warren, S. D.

1980-01-01

257

Quality assessment of Landsat surface reflectance products using MODIS data  

NASA Astrophysics Data System (ADS)

Surface reflectance adjusted for atmospheric effects is a primary input for land cover change detection and for developing many higher level surface geophysical parameters. With the development of automated atmospheric correction algorithms, it is now feasible to produce large quantities of surface reflectance products using Landsat images. Validation of these products requires in situ measurements, which either do not exist or are difficult to obtain for most Landsat images. The surface reflectance products derived using data acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS), however, have been validated more comprehensively. Because the MODIS on the Terra platform and the Landsat 7 are only half an hour apart following the same orbit, and each of the 6 Landsat spectral bands overlaps with a MODIS band, good agreements between MODIS and Landsat surface reflectance values can be considered indicators of the reliability of the Landsat products, while disagreements may suggest potential quality problems that need to be further investigated. Here we develop a system called Landsat-MODIS Consistency Checking System (LMCCS). This system automatically matches Landsat data with MODIS observations acquired on the same date over the same locations and uses them to calculate a set of agreement metrics. To maximize its portability, Java and open-source libraries were used in developing this system, and object-oriented programming (OOP) principles were followed to make it more flexible for future expansion. As a highly automated system designed to run as a stand-alone package or as a component of other Landsat data processing systems, this system can be used to assess the quality of essentially every Landsat surface reflectance image where spatially and temporally matching MODIS data are available. The effectiveness of this system was demonstrated using it to assess preliminary surface reflectance products derived using the Global Land Survey (GLS) Landsat images for the 2000 epoch. As surface reflectance likely will be a standard product for future Landsat missions, the approach developed in this study can be adapted as an operational quality assessment system for those missions.

Feng, Min; Huang, Chengquan; Channan, Saurabh; Vermote, Eric F.; Masek, Jeffrey G.; Townshend, John R.

2012-01-01

258

LANDSAT-D thermal analysis and design support  

NASA Technical Reports Server (NTRS)

Detailed thermal models of the LANDSAT-D Earth Sensor Assembly Module (ESAM), the Dummy Thematic Mapper (DTM), and a small thermal model of the LANDSAT-D spacecraft for a heater analysis were developed. These models were used to develop and verify the thermal design of the ESAM and DTM, to evaluate the aeroheating effects on ESAM during launch and to evaluate the thermal response of the LANDSAT-D assuming the hard-line heaters failed on with the spacecraft in the Space Transportation System (STS) orbiter bay. Results of model applications are summarized.

1982-01-01

259

Quality Assessment of Landsat Surface Reflectance Products Using MODIS Data  

NASA Technical Reports Server (NTRS)

Surface reflectance adjusted for atmospheric effects is a primary input for land cover change detection and for developing many higher level surface geophysical parameters. With the development of automated atmospheric correction algorithms, it is now feasible to produce large quantities of surface reflectance products using Landsat images. Validation of these products requires in situ measurements, which either do not exist or are difficult to obtain for most Landsat images. The surface reflectance products derived using data acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS), however, have been validated more comprehensively. Because the MODIS on the Terra platform and the Landsat 7 are only half an hour apart following the same orbit, and each of the 6 Landsat spectral bands overlaps with a MODIS band, good agreements between MODIS and Landsat surface reflectance values can be considered indicators of the reliability of the Landsat products, while disagreements may suggest potential quality problems that need to be further investigated. Here we develop a system called Landsat-MODIS Consistency Checking System (LMCCS). This system automatically matches Landsat data with MODIS observations acquired on the same date over the same locations and uses them to calculate a set of agreement metrics. To maximize its portability, Java and open-source libraries were used in developing this system, and object-oriented programming (OOP) principles were followed to make it more flexible for future expansion. As a highly automated system designed to run as a stand-alone package or as a component of other Landsat data processing systems, this system can be used to assess the quality of essentially every Landsat surface reflectance image where spatially and temporally matching MODIS data are available. The effectiveness of this system was demonstrated using it to assess preliminary surface reflectance products derived using the Global Land Survey (GLS) Landsat images for the 2000 epoch. As surface reflectance likely will be a standard product for future Landsat missions, the approach developed in this study can be adapted as an operational quality assessment system for those missions.

Feng, Min; Huang, Chengquan; Channan, Saurabh; Vermote, Eric; Masek, Jeffrey G.; Townshend, John R.

2012-01-01

260

An industrial perspective of the LANDSAT opportunity  

NASA Technical Reports Server (NTRS)

The feasibility of enhancing LANDSAT products to provide the greatest usability low cost data possible can be determined through government sponsorship and finance of one or more task forces composed of a critical number of experts in multiple disciplines from many industries and academia. The synergism of multiple minds addressing singular problems without the creation of permanent or perpetual structures must yield output in the form of implementable specifications, even if presented as alternatives. Changes are needed within the spacecraft in order to account for Sun angle changes. The use of pointing accuracy to make geometric corrections (and possible radiometric corrections, is needed more than onboard data reduction and information extraction, which assume a proper knowledge of application and reduce potential utilization. Multilinear arrays need to be investigated and methods for sensor calibration and for determining the effects of atmospheric inversion, as well as the best way to back out the modulation transfer function must be determined.

Williams, B. F.

1981-01-01

261

A LANDSAT digital image rectification system  

NASA Technical Reports Server (NTRS)

DIRS is a digital image rectification system for the geometric correction of LANDSAT multispectral scanner digital image data. DIRS removes spatial distortions from the data and brings it into conformance with the Universal Transverse Mercator (UTM) map projection. Scene data in the form of landmarks are used to drive the geometric correction algorithms. Two dimensional least squares polynominal and spacecraft attitude modeling techniques for geometric mapping are provided. Entire scenes or selected quadrilaterals may be rectified. Resampling through nearest neighbor or cubic convolution at user designated intervals is available. The output products are in the form of digital tape in band interleaved, single band or CCT format in a rotated UTM projection. The system was designed and implemented on large scale IBM 360 computers.

Vanwie, P.; Stein, M.

1976-01-01

262

Earth As Art 3: A Landsat Perspective  

NSDL National Science Digital Library

Circling high above the Earth, Landsat satellites have collected digital image photographs of the planet's continents and coastal areas. The Library of Congress has collected a number of these remarkable images (with the assistance of the United States Geological Survey) and visitors to this site can use the interactive features to zoom in and out on each image. The images have interesting titles, like "Empty Quarter", "Algerian Abstract", and "Ghostly Grease Ice". Each image can be sent as a postcard, and a brief paragraph or two describes the scene far below on the Earth's surface. Finally, visitor can also click on the "Learn More" tab to learn about additional web-based and print materials.

263

LANDSAT D local user terminal study  

NASA Technical Reports Server (NTRS)

The effect of the changes incorporated in the LANDSAT D system on the ability of a local user terminal to receive, record and process data in real time was studied. Alternate solutions to the problems raised by these changes were evaluated. A loading analysis was performed in order to determine the quantities of data that a local user terminal (LUT) would be interested in receiving and processing. The number of bits in an MSS and a TM scene were calculated along with the number of scenes per day that an LUT might require for processing. These then combined to a total number of processed bits/day for an LUT as a function of sensor and coverage circle radius.

Alexander, L.; Louie, M.; Spencer, R.; Stow, W. K.

1976-01-01

264

Monitoring tropical vegetation succession with LANDSAT data  

NASA Technical Reports Server (NTRS)

The shadowing problem, which is endemic to the use of LANDSAT in tropical areas, and the ability to model changes over space and through time are problems to be addressed when monitoring tropical vegetation succession. Application of a trend surface analysis model to major land cover classes in a mountainous region of the Phillipines shows that the spatial modeling of radiance values can provide a useful approach to tropical rain forest succession monitoring. Results indicate shadowing effects may be due primarily to local variations in the spectral responses. These variations can be compensated for through the decomposition of the spatial variation in both elevation and MSS data. Using the model to estimate both elevation and spectral terrain surface as a posteriori inputs in the classification process leads to improved classification accuracy for vegetation of cover of this type. Spatial patterns depicted by the MSS data reflect the measurement of responses to spatial processes acting at several scales.

Robinson, V. B. (principal investigator)

1983-01-01

265

Mesoscale cloud phenomena observed by LANDSAT  

NASA Technical Reports Server (NTRS)

Examples of certain mesoscale cloud features - jet cirrus, eddies/vortices, cloud banding, and wave clouds - were collected from LANDSAT imagery and placed into Mason's four groups of causes of cloud formation based on the mechanism of vertical motion which produces condensation. These groups are as follows: (1) layer clouds formed by widespread regular ascent; (2) layer clouds caused by irregular stirring motions; (3) convective clouds; and (4) clouds formed by orographic disturbances. These mechanisms explain general cloud formation. Once formed, other forces may play a role in the deformation of a cloud or cloud mass into unusual and unique meso- and microscale patterns. Each example presented is followed by a brief discussion describing the synoptic situation, and some inference into the formation and occurrence of the more salient features. No major attempt was made to discuss in detail the meteorological and topographic interplay producing these mesoscale features.

Ormsby, J. P.

1977-01-01

266

LANDSAT-D investigations in snow hydrology  

NASA Technical Reports Server (NTRS)

The sample LANDSAT-4 TM tape (7 bands) of NE Arkansas/Tennessee area was received and displayed. Snow reflectance in all 6 TM reflective bands, i.e. 1, 2, 3, 4, 5, and 7 was simulated, using Wiscombe and Warren's (1980) delta-Eddington model. Snow reflectance in bands 4, 5, and 7 appear sensitive to grain size. One of the objectives is to interpret surface optical grain size of snow, for spectral extension of albedo. While TM data of the study area are not received, simulation results are encouraging. It also appears that the TM filters resemble a "square-wave" closely enough to permit assuming a square-wave in calculations. Integrated band reflectance over the actual response functions was simulated, using sensor data supplied by Santa Barbara Research Center. Differences between integrating over the actual response functions and the equivalent square wave were negligible.

Dozier, J. (principal investigator)

1982-01-01

267

Microstructure and Properties of Nickel-Alloy and Nickel-WC Composite Overlays  

Microsoft Academic Search

The microstructures and performance of Ni-based alloys and Ni-WC (nickel-tungsten carbide) composite overlays deposited by plasma transferred arc welding have been studied. The Ni-alloy overlays had similar microstructures consisting of gamma-Ni dendrites, with interdendritic Ni-based eutectics, borides and carbides. Low hardness alloy overlays contained a smaller fraction of interdendritic phases relative to the high hardness alloys. The interdendritic regions make

Thilan Liyanage

2010-01-01

268

Water quality mapping using Landsat TM imagery  

NASA Astrophysics Data System (ADS)

Environmental monitoring through the method of traditional ship sampling is time consuming and requires a high survey cost. The objective of this study is to evaluate the feasibility of Landsat TM imagery for total suspended solids (TSS) mapping using a newly developed algorithm over Penang Island. The study area is the seawater region around Penang Island, Malaysia. Water samples were collected during a 3-hour period simultaneously with the satellite image acquisition and later analyzed in the laboratory above the study area. The samples locations were determined using a handheld GPS. The satellite image was geometrically corrected using the second order polynomial transformation. The satellite image also was atmospheric corrected by using ATCOR2 image processing software. The digital numbers for each band corresponding to the sea-truth locations were extracted and then converted into reflectance values for calibration of the water quality algorithm. The proposed algorithm is based on the reflectance model that is a function of the inherent optical properties of water, which can be related to its constituent's concentrations. The generated algorithm was developed for three visible wavelenghts, red, green and blue for this study. Results indicate that the proposed developed algorithm was superior based on the correlation coefficient (R) and root-mean-square deviation (RMS) values. Finally the proposed algorithm was used for TSS mapping at Penang Island, Malaysia. The generated TSS map was colour-coded for visual interpretation and image smoothing was performed on the map to remove random noise. This preliminary study has produced a promising result. This study indicates that the empirical algorithm is suitable for TSS mapping around Penang Island by using satellite Landsat TM data.

Lim, H. S.; MatJafri, M. Z.; Abdullah, K.; Alias, A. N.; Wong, C. J.; Mustapha-Rosli, M. R.; Mohd Saleh, N.

2009-05-01

269

Compensating process non-uniformity to improve wafer overlay by RegC  

NASA Astrophysics Data System (ADS)

The introduction of double and triple patterning tightened the Overlay current nodes' specifications across the industry to levels of 5nm and 3nm respectively. Overlay error is a combination of Intra-field and field-to-field errors. The Intra-field error includes several systematic signatures, such as overlay magnitude differences between X and Y axes, field center vs edge and more. The recent developments in scanner technology improved the intra-field Overlay to high orders. In this work we have quantified the state-of-the-art residual overlay errors and applied the RegC® (registration/overlay control) process, a new solution of deep sub-nanometer pattern shift, to further improve the overlay process control, in addition to the current lithography's state-of-the-art capabilities. As a result we managed to reduce the baseline overlay error by more than one nanometer and reduced systematic intrafield non-uniformities, by removing the 3 sigma difference between X and Y to zero. The combination of intra-field control by RegC® with high order correction per exposure (CPE) by the scanner provides a new era of overlay control required for the 2x and 1x multiple patterning processes.

Leray, Philippe; Cheng, Shaunee; Cohen, Avi; Graitzer, Erez; Dmitriev, Vladimir; Rehtan, Shiran; Wertsman, Nadav

2014-04-01

270

Employing Multicast in P2P Overlay Networks  

NASA Astrophysics Data System (ADS)

The work on multicast has evolved from bottom IP layer multicast to Application Layer Multicast. While there are issues with the dep-loyment of IP layer multicast, it outperforms Application Layer Multicast. However, the latter has the advantage of an easier dep-loyment. Furthermore, as will be illustrated later in this Chapter, IP layer multicast has the potential to make parallel overlay operations more efficient. Application Layer Multicast is primarily used to send application specific messages/data to a number of nodes.

Kolberg, Mario

271

Bandwidth auction for SVC streaming in dynamic multi-overlay  

NASA Astrophysics Data System (ADS)

In this paper, we study the optimal bandwidth allocation for scalable video coding (SVC) streaming in multiple overlays. We model the whole bandwidth request and distribution process as a set of decentralized auction games between the competing peers. For the upstream peer, a bandwidth allocation mechanism is introduced to maximize the aggregate revenue. For the downstream peer, a dynamic bidding strategy is proposed. It achieves maximum utility and efficient resource usage by collaborating with a content-aware layer dropping/adding strategy. Also, the convergence of the proposed auction games is theoretically proved. Experimental results show that the auction strategies can adapt to dynamic join of competing peers and video layers.

Xiong, Yanting; Zou, Junni; Xiong, Hongkai

2010-07-01

272

Advances in process overlay on 300-mm wafers  

NASA Astrophysics Data System (ADS)

Overlay budgets are getting tighter within 300 mm volume production and as a consequence the process effects on alignment and off-line metrology becomes more important. In a short loop experiment, with cleared reference marks in each image field, the isolated effect of processing was measured with a sub-nanometer accuracy. The examined processes are Shallow Trench Isolation (STI), Tungsten-Chemical Mechanical Processing (W-CMP) and resist spinning. The alignment measurements were done on an ASML TWINSCANT scanner and the off-line metrology measurements on a KLA Tencor. Mark type and mark position dependency of the process effects are analyzed. The mean plus 3 (sigma) of the maximum overlay after correcting batch average wafer parameters is used as an overlay performance indicator (OPI). 3 (sigma) residuals to the wafer-model are used as an indicator of the noise that is added by the process. The results are in agreement with existing knowledge of process effects on 200 mm wafers. The W-CMP process introduces an additional wafer rotation and scaling that is similar for alignment marks and metrology targets. The effects depend on the mark type; in general they get less severe for higher spatial frequencies. For a 7th order alignment mark, the OPI measured about 12 nm and the added noise about 12 nm. For the examined metrology targets the OPI is about 20 nm with an added noise of about 90 nm. Two different types of alignment marks were tested in the STI process, i.e., zero layer marks and marks that were exposed together with the STI product. The overlay contribution due to processing on both types of alignment marks is very low (smaller than 5 nm OPI) and independent on mark type. Some flyers are observed fot the zero layer marks. The flyers can be explained by the residues of oxide and nitride that is left behind in the spaces of the alignment marks. Resist spinning is examined on single layer resist and resist with an organic Bottom Anti-Reflective Coating (BARC) underneath. Single layer resist showed scaling on unsegmented marks that disappears using higher diffraction orders and/or mark segmentation. Resist with a planarizing BARC caused additional effects on the wafer edge for measurements with the red laser signal. The effects disappear using the green laser of ATHENAT.

Staecker, Jens; Arendt, Stefanie; Schumacher, Karl; Mos, Evert C.; van Haren, Richard J. F.; van der Schaar, Maurits; Edart, Remi; Demmerle, Wolfgang; Tolsma, Hoite

2002-07-01

273

CCRS proposal for evaluating LANDSAT-4 MSS and TM data  

NASA Technical Reports Server (NTRS)

The measurement of registration errors in LANDSAT MSS data is discussed as well as the development of a revised algorithm for the radiometric calibration of TM data and the production of a geocoded TM image.

Strome, W. M.; Cihlar, J.; Goodenough, D. G.; Guertin, F. E. (principal investigators); Guindon, B.; Murphy, J.; Butlin, J. M.; Duff, P.; Fitzgerald, A.; Grieve, G.

1984-01-01

274

Application of the ITD algorithm to Landsat orbital transient responses  

NASA Technical Reports Server (NTRS)

The topics are presented in viewgraph form and include the following: Landsat 4 system description; five degree-of-freedom system example problem; orbital finite element model analysis; and measured orbital data analysis.

Kauffman, R. R.

1988-01-01

275

LANDSAT data for state planning. [of transportation for Georgia  

NASA Technical Reports Server (NTRS)

The results of an effort to generate and apply automated classification of LANDSAT digital data to state of Georgia problems are presented. This phase centers on an analysis of the usefulness of LANDSAT digital data to provide land-use data for transportation planning. Hall County, Georgia was chosen as a test site because it is part of a seventeen county area for which the Georgia Department of Transportation is currently designing a Transportation Planning Land-Use Simulation Model. The land-cover information derived from this study was compared to several other existing sources of land-use data for Hall County and input into this simulation. The results indicate that there is difficulty comparing LANDSAT derived land-cover information with previous land-use information since the LANDSAT data are acquired on an acre by acre grid basis while all previous land-use surveys for Hall County used land-use data on a parcel basis.

Faust, N. L.; Spann, G. W.

1975-01-01

276

Comparing EO-1-Hyperions spectral resolution to Landsat  

NSDL National Science Digital Library

The Landsat system covers 7 spectral bands (of which six are shown here) while the Hyperion instrument records data in 220 bands from 353 nanometers to 2577 nanometers. This animation shows how they stack up.

Bridgman, Tom; Ungar, Stephen; Ong, Lawrence

2001-04-09

277

Landsat: 25 Years in the Pacific Northwest Forest  

NASA Video Gallery

This visualization shows a sequence of Landsat-based data in the Pacific Northwest. There is one data set for each year representing an aggregate of the approximate peak of the growing season (arou...

278

A case study in the practical use of LANDSAT data  

NASA Technical Reports Server (NTRS)

The use of computer aided classification of LANDSAT data in developing water quality plans for New Jersey watersheds is used to exemplify how a state natural resource management program benefits from satellite imagery. The transition of a research and development system into an operational remote sensing system to help decision makers is demonstrated. Nontechnial issues that can assist (or hinder) an agency in adopting a new technology are examined. The progress of LANDSAT use by state government from the earliest stage of curiosity through to incorporation in actual state planning methods is charted. Potential applications of LANDSAT data to real information needs and solutions to management problems are examined. The problems and mistakes that occurred in using LANDSAT data in the past are discussed as well as the ways by which these problems were overcome.

Cox, S.

1982-01-01

279

Case study in the practical use of LANDSAT data  

SciTech Connect

The use of computer aided classification of LANDSAT data in developing water quality plans for New Jersey watersheds is used to exemplify how a state natural resource management program benefits from satellite imagery. The transition of a research and development system into an operational remote sensing system to help decision makers is demonstrated. Nontechnial issues that can assist (or hinder) an agency in adopting a new technology are examined. The progress of LANDSAT use by state government from the earliest stage of curiosity through to incorporation in actual state planning methods is charted. Potential applications of LANDSAT data to real information needs and solutions to management problems are examined. The problems and mistakes that occurred in using LANDSAT data in the past are discussed as well as the ways by which these problems were overcome.

Cox, S.

1982-01-01

280

Application of LANDSAT images in the Minas Gerais tectonic division  

NASA Technical Reports Server (NTRS)

The interpretation of LANDSAT data for a regional geological investigation of Brazil is provided. Radar imagery, aerial photographs and aeromagnetic maps were also used. Automatic interpretation, using LANDSAT OCT's was carried out by the 1-100 equipment. As a primary result a tectonic map was obtained, at 1:1,000,000 scale, of an area of about 143,000 square kilometers, in the central portion of Minas Gerais and Eastern Goias States, known as regions potentially rich in mineral resources.

Dacunha, R. P.; Demattos, J. T.

1978-01-01

281

Monitoring forest succession with multitemporal Landsat images: factors of uncertainty  

Microsoft Academic Search

This study evaluates uncertainty factors in using multitemporal Landsat images for subtle change detection, including atmosphere, topography, phenology, and sun and view angles. The study is based on monitoring forest succession with a set of multiple Landsat Thematic Mapper\\/Enhanced Thematic Mapper Plus (TM\\/ETM+) images spanning 15 years over the H.J. Andrews Experimental Forest in the Western Cascades of Oregon. The

Conghe Song; Curtis E. Woodcock

2003-01-01

282

Hydrography synthesis using LANDSAT remote sensing and the SCS models  

NASA Technical Reports Server (NTRS)

The land cover requirements of the Soil Conservation Service (SCS) Model used for hydrograph synthesis in urban areas were modified to be LANDSAT compatible. The Curve Numbers obtained with these alternate land cover categories compare well with those obtained in published example problems using the conventional categories. Emergency spillway hydrographs and synthetic flood frequency flows computed for a 21.1 sq. mi. test area showed excellent agreement between the conventional aerial photo-based and the Landsat-based SCS approaches.

Ragan, R. M.; Jackson, T. J.

1976-01-01

283

LANDSAT-4 multispectral scanner (MSS) subsystem radiometric characterization  

NASA Technical Reports Server (NTRS)

The multispectral band scanner (mass) and its spectral characteristics are described and methods are given for relating video digital levels on computer compatible tapes to radiance into the sensor. Topics covered include prelaunch calibration procedures and postlaunch radiometric processng. Examples of current data resident on the MSS image processing system are included. The MSS on LANDSAT 4 is compared with the scanners on earlier LANDSAT satellites.

Alford, W. (editor); Barker, J. (editor); Clark, B. P.; Dasgupta, R.

1983-01-01

284

Spectral characterization of the LANDSAT Thematic Mapper sensors  

Microsoft Academic Search

A summary of the spectral characteristics of the LANDSAT-4 and LANDSAT-5 Thematic Mapper instruments, the protoflight (TM\\/PF) and flight (TM\\/F) models, respectively, is presented. Data collected by the Hughes\\/Santa Barbara Research Center on the instruments and their components to determine compliance with the spectral coverage and spectral matching specifications served as the basis for the characterization. Compliance with the spectral

BRIAN L. MARKHAM; JOHN L. BARKER

1985-01-01

285

An Overview of the Landsat Data Continuity Mission  

NASA Technical Reports Server (NTRS)

The advent of the Landsat Data Continuity Mission (LDCM), currently with a launch readiness date of December, 2012, will see evolutionary changes in the Landsat data products available from the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center. The USGS initiated a revolution in 2009 when EROS began distributing Landsat data products at no cost to requestors in contrast to the past practice of charging the cost of fulfilling a request; that is, charging $600 per Landsat scene. To implement this drastic change, EROS terminated data processing options for requestors and began to produce all data products using a consistent processing recipe. EROS plans to continue this practice for the LDCM and will required new algorithms to process data from the LDCM sensors. All previous Landsat satellites flew multispectral scanners to collect image data of the global land surface. Additionally, Landsats 4, 5, and 7 flew sensors that acquired imagery for both reflective spectral bands and a single thermal band. In contrast, the LDCM will carry two pushbroom sensors; the Operational Land Imager (OLI) for reflective spectral bands and the Thermal InfraRed Sensor (TIRS) for two thermal bands. EROS is developing the ground data processing system that will both calibrate and correct the data from the thousands of detectors employed by the pushbroom sensors and that will also combine the data from the two sensors to create a single data product with registered data for all of the OLI and TIRS bands.

Irons, James R.; Dwyer, John L.

2010-01-01

286

Lightweight storage and overlay networks for fault tolerance.  

SciTech Connect

The next generation of capability-class, massively parallel processing (MPP) systems is expected to have hundreds of thousands to millions of processors, In such environments, it is critical to have fault-tolerance mechanisms, including checkpoint/restart, that scale with the size of applications and the percentage of the system on which the applications execute. For application-driven, periodic checkpoint operations, the state-of-the-art does not provide a scalable solution. For example, on today's massive-scale systems that execute applications which consume most of the memory of the employed compute nodes, checkpoint operations generate I/O that consumes nearly 80% of the total I/O usage. Motivated by this observation, this project aims to improve I/O performance for application-directed checkpoints through the use of lightweight storage architectures and overlay networks. Lightweight storage provide direct access to underlying storage devices. Overlay networks provide caching and processing capabilities in the compute-node fabric. The combination has potential to signifcantly reduce I/O overhead for large-scale applications. This report describes our combined efforts to model and understand overheads for application-directed checkpoints, as well as implementation and performance analysis of a checkpoint service that uses available compute nodes as a network cache for checkpoint operations.

Oldfield, Ron A.

2010-01-01

287

Using perspective guidance overlay to improve UAV manual control performance  

NASA Astrophysics Data System (ADS)

The guidance information that is available to the UAV operator typically suffers from limitations of data update rate and system latency. Even when using a flight director command display, the manual control task is considerably more difficult compared to piloting a manned aircraft. Results from earlier research into perspective guidance displays show that these displays provide performance benefits and suggest a reduction of the negative effects of system latency. The current study has shown that in case of limitations of data update rate and system latency the use of a conformal sensor overlay showing a perspective presentation of the trajectory constraints is consistently superior to the flight director command display. The superiority becomes more pronounced with an increase in data latency and a decrease in update rate. The fact that the perspective pathway overlay as used in this study can be implemented on any graphics system that is capable of rendering a set of 2-D vectors makes it a viable candidate for upgrades to current systems.

Tadema, Jochum; Theunissen, Erik; Koeners, Joris

2007-04-01

288

The interfacial microstructure of weld overlay of corrosion resistant alloys  

SciTech Connect

For reasons of economy, hydrogenation pressure vessels of heavy wall sections are fabricated by cladding with one or more layers of austenitic stainless steel on the inside of the vessel wall. Submerged Arc Welding with strip-electrode technology is used in this process because of its ability to combine excellent deposit properties and controllable penetration with high deposition rates. However, hydrogen-related disbonding of the clad-overlay is a problem remaining in the use of the composite pressure vessels in petrochemical industries. One of the major factors contributing to the disbonding is the microstructure developed during solidification of the weld metal. It is unclear what kind of microstructure is most susceptible to disbonding and how the microstructure develops. Marshall and Lazor et al. believed that martensitic structures were the culprit for the initiation of disbonding. Ohnishi et al. concluded from their investigation that a layer of martensite adjacent to the fusion line would reduce the disbonding. Recently, Godden et al. found that a so-called Type 2 grain boundary was the most susceptible structure to the disbonding, but the mechanism is not clear. This study investigated the microstructures along the interface between overlays and base steel and established the mechanism of the formation of crack-susceptible microstructures.

Wu, Yunjian; Patchett, B.M.; Bicknell, C. (Univ. of Alberta, Edmonton, Alberta (Canada))

1994-05-01

289

Modeling Patterning of Heteroepitaxial Overlayers from Nano to Micron Scales  

NASA Astrophysics Data System (ADS)

Thin heteroepitaxial overlayers have been proposed as templates to generate stable, self-organized nanostructures at large length scales, with a variety of important technological applications. However, modeling strain-driven self-organization is a formidable challenge due to a large span of length and time scales involved. In this talk, I will present a method for predicting the patterning of ultrathin films on micron length scales with atomic resolution [K.R. Elder et al., Phys. Rev. Lett. 108, 226102 (2012)]. It is based on the Phase-Field Crystal model, which allows one to reach diffusive time scales for relaxation of the system. We make quantitative predictions for the type of superstructures (stripes, honeycomb, triangular) and length scales of pattern formation of both compressively strained and tensile overlayers on metal-metal systems, including Cu on Ru(0001), Cu on Pd(111), and Ag on Cu(111). Our findings are in excellent agreement with previous experiments and call for future experimental investigations of such systems.

Ala-Nissila, Tapio

2013-03-01

290

Coded multiple chirp spread spectrum system and overlay service  

NASA Astrophysics Data System (ADS)

An asynchronous spread-spectrum system called coded multiple chirp is proposed, and the possible spread-spectrum overlay over an analog FM-TV signal is investigated by computer simulation. Multiple single-sloped up and down chirps are encoded by a pseudonoise code and decoded by dechirpers (pulse-compression filters) followed by a digital code correlator. The performance of the proposed system, expressed in terms of in probability of bit error and code miss probability, is similar to that of FSK (frequency shift keying) using codewords if sufficient compression gain is used. When chirp is used to overlay an FM-TV channel, two chirp signals with data rate up to 25 kb/s could be overlaid in a 36-MHz satellite transponder without significant mutual interference. Performance estimates for a VSAT (very small aperture terminal) earth station operating at C-band show that a 2.4-m antenna and 300-mW transmitter could send a 2.4-kb/s signal to a large central earth station over an occupied channel.

Kim, Junghwan; Pratt, Timothy; Ha, Tri T.

291

Coded multiple chirp spread spectrum system and overlay service  

NASA Technical Reports Server (NTRS)

An asynchronous spread-spectrum system called coded multiple chirp is proposed, and the possible spread-spectrum overlay over an analog FM-TV signal is investigated by computer simulation. Multiple single-sloped up and down chirps are encoded by a pseudonoise code and decoded by dechirpers (pulse-compression filters) followed by a digital code correlator. The performance of the proposed system, expressed in terms of in probability of bit error and code miss probability, is similar to that of FSK (frequency shift keying) using codewords if sufficient compression gain is used. When chirp is used to overlay an FM-TV channel, two chirp signals with data rate up to 25 kb/s could be overlaid in a 36-MHz satellite transponder without significant mutual interference. Performance estimates for a VSAT (very small aperture terminal) earth station operating at C-band show that a 2.4-m antenna and 300-mW transmitter could send a 2.4-kb/s signal to a large central earth station over an occupied channel.

Kim, Junghwan; Pratt, Timothy; Ha, Tri T.

1988-01-01

292

Upper Klamath Basin Landsat Image for June 24, 2006: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-7 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-7 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-7 on April 15, 1999 marks the addition of the latest satellite to the Landsat series. The Landsat-7 satellite carries the Enhanced Thematic Mapper Plus (ETM+) sensor. A mechanical failure of the ETM+ Scan Line Corrector (SLC) occurred on May 31, 2003, with the result that all Landsat 7 scenes acquired from July 14, 2003 to present have been collected in 'SLC-off' mode. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

293

Upper Klamath Basin Landsat Image for July 10, 2006: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-7 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-7 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-7 on April 15, 1999 marks the addition of the latest satellite to the Landsat series. The Landsat-7 satellite carries the Enhanced Thematic Mapper Plus (ETM+) sensor. A mechanical failure of the ETM+ Scan Line Corrector (SLC) occurred on May 31, 2003, with the result that all Landsat 7 scenes acquired from July 14, 2003 to present have been collected in 'SLC-off' mode. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

294

Upper Klamath Basin Landsat Image for July 11, 2004: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-7 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-7 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-7 on April 15, 1999 marks the addition of the latest satellite to the Landsat series. The Landsat-7 satellite carries the Enhanced Thematic Mapper Plus (ETM+) sensor. A mechanical failure of the ETM+ Scan Line Corrector (SLC) occurred on May 31, 2003, with the result that all Landsat 7 scenes acquired from July 14, 2003 to present have been collected in 'SLC-off' mode. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

295

Upper Klamath Basin Landsat Image for April 28, 2006: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-7 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-7 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-7 on April 15, 1999 marks the addition of the latest satellite to the Landsat series. The Landsat-7 satellite carries the Enhanced Thematic Mapper Plus (ETM+) sensor. A mechanical failure of the ETM+ Scan Line Corrector (SLC) occurred on May 31, 2003, with the result that all Landsat 7 scenes acquired from July 14, 2003 to present have been collected in 'SLC-off' mode. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

296

Upper Klamath Basin Landsat Image for May 30, 2006: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-7 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-7 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-7 on April 15, 1999 marks the addition of the latest satellite to the Landsat series. The Landsat-7 satellite carries the Enhanced Thematic Mapper Plus (ETM+) sensor. A mechanical failure of the ETM+ Scan Line Corrector (SLC) occurred on May 31, 2003, with the result that all Landsat 7 scenes acquired from July 14, 2003 to present have been collected in 'SLC-off' mode. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

297

Metrology tool fleet management: applying FMP tool matching and monitoring concepts to an overlay fleet  

NASA Astrophysics Data System (ADS)

Overlay tool matching and accuracy issues are quickly reaching a comparable complexity to that of critical dimensional metrology. While both issues warrant serious investigation, this paper deals with the matching issues associated with overlay tools. Overlay tools need to run and measure as if they are a single tool - they need to act as one. In this paper a matching methodology is used to assess a set of overlay tools in a multiple of overlay applications. The methodology proposed in a prior2 SPIE paper is applied here to a fleet of two generations of overlay tools to detect measurement problems not seen with convention Statistical Process Control techniques. Four studies were used to examine the benefits of this matching methodology for this fleet of overlay tools. The first study was a matching assessment study. The second study was a hardware comparison between generations of tools. The third study was a measurement strategy comparison. The final study was a long term matching exercise where one example of a traditional long term monitoring strategy was compared to a new long term monitoring strategy. It is shown that this new tool matching method can be effectively applied to overlay metrology.

Morningstar, Jennifer; Solecky, Eric; Archie, Chas; Banke, Bill

2006-03-01

298

Towards a Common API for Structured Peer-to-Peer Overlays  

Microsoft Academic Search

In this paper, we describe an ongoing effort to define com- mon APIs for structured peer-to-peer overlays and the key abstractions that can be built on them. In doing so, we hope to facilitate independent innovation in overlay pro- tocols, services, and applications, to allow direct experi- mental comparisons, and to encourage application devel- opment by third parties. We provide

Frank Dabek; Ben Y. Zhao; Peter Druschel; John Kubiatowicz; Ion Stoica

2003-01-01

299

OMAN -A Management Architecture for P2P Service Overlay Networks  

E-print Network

OMAN - A Management Architecture for P2P Service Overlay Networks Adriano Fiorese1,2 , Paulo Sim Overlay Net- works (SON). The architecture, named OMAN, takes into account the formation of the P2P SON as pointing the overall potential of the OMAN archi- tecture. Keywords:Services Management, P2P, Service

Boyer, Edmond

300

Sepidar: Incentivized Market-Based P2P Live-Streaming on the Gradient Overlay Network  

Microsoft Academic Search

Live streaming of video content using overlay networks has gained widespread adoption on the Internet. This paper presents Sepidar, a distributed market-based model, that builds and maintains overlay network trees, which are approximately minimal height, for delivering live media as a number of sub streams. A streaming tree is constructed for each sub stream such that nodes that contribute higher

Amir H. Payberah; Fatemeh Rahimian; Seif Haridi; Jim Dowling

2010-01-01

301

Viral concentration determination through plaque assays: using traditional and novel overlay systems.  

PubMed

Plaque assays remain one of the most accurate methods for the direct quantification of infectious virons and antiviral substances through the counting of discrete plaques (infectious units and cellular dead zones) in cell culture. Here we demonstrate how to perform a basic plaque assay, and how differing overlays and techniques can affect plaque formation and production. Typically solid or semisolid overlay substrates, such as agarose or carboxymethyl cellulose, have been used to restrict viral spread, preventing indiscriminate infection through the liquid growth medium. Immobilized overlays restrict cellular infection to the immediately surrounding monolayer, allowing the formation of discrete countable foci and subsequent plaque formation. To overcome the difficulties inherent in using traditional overlays, a novel liquid overlay utilizing microcrystalline cellulose and carboxymethyl cellulose sodium has been increasingly used as a replacement in the standard plaque assay. Liquid overlay plaque assays can be readily performed in either standard 6 or 12 well plate formats as per traditional techniques and require no special equipment. Due to its liquid state and subsequent ease of application and removal, microculture plate formats may alternatively be utilized as a rapid, accurate and high throughput alternative to larger scale viral titrations. Use of a non heated viscous liquid polymer offers the opportunity to streamline work, conserves reagents, incubator space, and increases operational safety when used in traditional or high containment labs as no reagent heating or glassware are required. Liquid overlays may also prove more sensitive than traditional overlays for certain heat labile viruses. PMID:25407402

Baer, Alan; Kehn-Hall, Kylene

2014-01-01

302

RESEARCH REPORT 987-9 ASPHALT OVERLAY DESIGN METHODS FOR RIGID  

E-print Network

RESEARCH REPORT 987-9 ASPHALT OVERLAY DESIGN METHODS FOR RIGID PAVEMENTS CONSIDERING RUTTING FOR TRANSPORTATION RESEARCH BUREAU OF ENGINEERING RESEARCH THE UNIVERSITY OF TEXAS AT AUSTIN OCTOBER 1998 #12's Catalog No. 5. Report Date October 1998 4. Title and Subtitle ASPHALT OVERLAY DESIGN METHODS FOR RIGID

Texas at Austin, University of

303

CodedStream: Live Media Streaming with Overlay Coded Jiang Guo, Ying Zhu, Baochun Li  

E-print Network

CodedStream: Live Media Streaming with Overlay Coded Multicast Jiang Guo, Ying Zhu, Baochun Li in the overlay network remain unused. In this paper, we propose CodedStream, a high-bandwidth live media and network coding may indeed bring significant benefits with respect to improving the quality of live media

Li, Baochun

304

Improving the accuracy of overlay measurement through wafer sampling map rearrangement  

Microsoft Academic Search

In this study, different sampling methods for alignment and overlay measurement were compared. Several types of wafer map, such as symmetry, asymmetry, and random were tested. In order to characterize the performance of each sampling plan, criteria including the alignment error, overlay measurement data and the final registration result after adjusting stepper parameters were examined. The compensation value for exposure

Chungwei Hsu; Ron Chu; Jen H. Chen

1999-01-01

305

Constructing the Overlay Network by Tuning Link Huijuan Wang and Piet Van Mieghem  

E-print Network

or virtual private networks can be considered as a subgraph of Gspt. We construct two types of Gspt: (a) Gspt of overlay network is a virtual private network (VPN), a private network that uses a public network (usuallyConstructing the Overlay Network by Tuning Link Weights Huijuan Wang and Piet Van Mieghem Delft

Van Mieghem, Piet

306

Backup Path Allocation Based On A Correlated Link Failure Probability Model In Overlay Networks  

E-print Network

failure probability between the primary and the backup paths. To demonstrate the feasibility of ourBackup Path Allocation Based On A Correlated Link Failure Probability Model In Overlay Networks. As a result, although we may select a disjoint backup path at the overlay layer, one physical link failure may

California at Irvine, University of

307

AOS: an anonymous overlay system for mobile ad hoc networks Rui Zhang Yanchao Zhang Yuguang Fang  

E-print Network

AOS: an anonymous overlay system for mobile ad hoc networks Rui Zhang · Yanchao Zhang · Yuguang anonymous communications in mobile ad hoc networks (MANETs) is an effective coun- termeasure against malicious traffic analysis. This paper presents AOS, an Anonymous Overlay System for MA- NETs, which

Latchman, Haniph A.

308

Wafer based aberration metrology for lithographic systems using overlay measurements on targets  

E-print Network

Wafer based aberration metrology for lithographic systems using overlay measurements on targets projection system from wafer metrology data. For this, new types of phase-shift gratings (PSG) are introduced metrology tool. In this way, the overlay error can be used as a measurand based on which the phase

309

Effect of heat treatment on the precipitation and pitting corrosion behavior of 347 SS weld overlay  

Microsoft Academic Search

The effect of heat treatment on the microstructure and corrosion performance of 347 SS weld overlay has been investigated. The microstructure and phase change of the as-welded and post weld heat treated (PWHT) overlays were examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Energy dispersive spectroscopy (EDS) was also used for intermetallic phase identification. The results showed

I-Hsuang Lo; Wen-Ta Tsai

2003-01-01

310

Questioning the Benefits That Coloured Overlays Can Have for Reading in Students with and without Dyslexia  

ERIC Educational Resources Information Center

Visual stress (the experience of visual distortions and discomfort during prolonged reading) is frequently identified and alleviated with coloured overlays or lenses. Previous studies have associated visual stress with dyslexia and as a consequence, coloured overlays are widely distributed to children and adults with reading difficulty. However,…

Henderson, Lisa M.; Tsogka, Natassa; Snowling, Margaret J.

2013-01-01

311

Content-Based Peer-to-Peer Network Overlay for Full-Text Federated Search  

E-print Network

Content-Based Peer-to-Peer Network Overlay for Full-Text Federated Search Jie Lu Jamie Callan network overlay for full-text federated search over heterogeneous, open-domain contents. Local algorithms for providing federated search to large-scale networks of text digital libraries. Search in current P2P networks

Callan, Jamie

312

Exploiting skewness to build an optimal hedge fund with a currency overlay  

Microsoft Academic Search

This paper documents an investigation into the use of portfolio selection methods to construct a hedge fund with a currency overlay. The fund, which is based on number of international stock and bond market indices and is constructed from the perspective of a Sterling investor, allows the individual exposures in the currency overlay to be optimally determined. As well as

C. J. Adcock

2005-01-01

313

Debunking some myths about structured and unstructured overlays Miguel Castro Manuel Costa Antony Rowstron  

E-print Network

Debunking some myths about structured and unstructured overlays Miguel Castro Manuel Costa Antony study using sim- ulations driven by real-world traces that debunks these widespread myths. We describe to this debate by debunking some widespread myths. Unstructured overlays, for example Gnutella [1], or- ganize

Narasayya, Vivek

314

LANDSAT-4 horizon scanner performance evaluation  

NASA Technical Reports Server (NTRS)

Representative data spans covering a little more than a year since the LANDSAT-4 launch were analyzed to evaluate the flight performance of the satellite's horizon scanner. High frequency noise was filtered out by 128-point averaging. The effects of Earth oblateness and spacecraft altitude variations are modeled, and residual systematic errors are analyzed. A model for the predicted radiance effects is compared with the flight data and deficiencies in the radiance effects modeling are noted. Correction coefficients are provided for a finite Fourier series representation of the systematic errors in the data. Analysis of the seasonal dependence of the coefficients indicates the effects of some early mission problems with the reference attitudes which were computed by the onboard computer using star trackers and gyro data. The effects of sun and moon interference, unexplained anomalies in the data, and sensor noise characteristics and their power spectrum are described. The variability of full orbit data averages is shown. Plots of the sensor data for all the available data spans are included.

Bilanow, S.; Chen, L. C.; Davis, W. M.; Stanley, J. P.

1984-01-01

315

LANDSAT-4 image data quality analysis  

NASA Technical Reports Server (NTRS)

Work done on evaluating the geometric and radiometric quality of early LANDSAT-4 sensor data is described. Band to band and channel to channel registration evaluations were carried out using a line correlator. Visual blink comparisons were run on an image display to observe band to band registration over 512 x 512 pixel blocks. The results indicate a .5 pixel line misregistration between the 1.55 to 1.75, 2.08 to 2.35 micrometer bands and the first four bands. Also a four 30M line and column misregistration of the thermal IR band was observed. Radiometric evaluation included mean and variance analysis of individual detectors and principal components analysis. Results indicate that detector bias for all bands is very close or within tolerance. Bright spots were observed in the thermal IR band on an 18 line by 128 pixel grid. No explanation for this was pursued. The general overall quality of the TM was judged to be very high.

Anuta, P. E. (principal investigator)

1982-01-01

316

Landsat classification of Argentina summer crops  

NASA Technical Reports Server (NTRS)

A Landsat MSS and TM classification approach based on three features derived from the greenness profile has proved very effective in separating and identifying corn, soybeans, and other ground cover classes in the U.S. The objective of this study is to investigate the separation of summer crops in Argentina, one of the most important commodity exporters, using the same greenness profile features that have proved effective in the U.S. Corn Belt. The area chosen for study is a more complex cropping practice area located in the north-west corner of Buenos Aires province in Pampa Humeda, where corn, soybean, sorghum, sunflower, and pastures are cultivated. It is shown that the profile features can provide very effective separation, except in the case of corn from sorghum. Separation between corn and soybeans was found to be greater than in the U.S. This study suggests that the automatic, unsupervised classification approach developed in the U.S., with relatively minor modification, can be used for summer crop area estimation in Argentina.

Badhwar, G. D.; Gargantini, C. E.; Redondo, F. V.

1987-01-01

317

Landsat data conversion cut from budget  

NASA Astrophysics Data System (ADS)

The conversion of a set of early Landsat data from wide band videotape to digitized, computer-compatible form is slated to end prematurely when this fiscal year ends on September 30, 1986. The National Aeronautics and Space Administration (NASA) is shutting down the project to save money because of the Gramm-Rudman-Hollings deficit reduction act (Eos, January 28, 1986, p. 41) and in view of the strain on NASA's budget caused by the loss of the space shuttle Challenger, according to Joseph Bishop, program manager for data processing in NASA's Office of Space Tracking and Data Systems. Moreover, the only equipment that can be used to read the wide band videotape data and convert it to computer-compatible tape (CCT) has become obsolete, and the tapes themselves are deteriorating, so it seems unlikely that this project could be renewed in the future, according to Allen H. Watkins, chief of the Earth Resources Observation System (EROS) Data Center of the U.S. Geological Survey in Sioux Falls, S. Dak.

Katzoff, Judith A.

318

Landsat Data Continuity Mission - Launch Fever  

NASA Technical Reports Server (NTRS)

The year 2013 will be an exciting period for those that study the Earth land surface from space, particularly those that observe and characterize land cover, land use, and the change of cover and use over time. Two new satellite observatories will be launched next year that will enhance capabilities for observing the global land surface. The United States plans to launch the Landsat Data Continuity Mission (LDCM) in January. That event will be followed later in the year by the European Space Agency (ESA) launch of the first Sentinel 2 satellite. Considered together, the two satellites will increase the frequency of opportunities for viewing the land surface at a scale where human impact and influence can be differentiated from natural change. Data from the two satellites will provide images for similar spectral bands and for comparable spatial resolutions with rigorous attention to calibration that will facilitate cross comparisons. This presentation will provide an overview of the LDCM satellite system and report its readiness for the January launch.

Irons, James R.; Loveland, Thomas R.; Markham, Brian L.; Masek, Jeffrey G.; Cook, Bruce; Dwyer, John L.

2012-01-01

319

Characterization of the LANDSAT sensors' spatial responses  

NASA Technical Reports Server (NTRS)

The characteristics of the thematic mapper (TM) and multispectral scanner (MSS) sensors on LANDSATs 4 and 5 affecting their spatial responses are described, and functions defining the response of the system to an arbitrary input spatial pattern are derived, i.e., transfer functions (TF) and line spread functions (LSF). These design LSF's and TF's were modified based on prelaunch component and system measurements to provide improved estimates. Prelaunch estimates of LSF/FT's are compared to in-orbit estimates. For the MSS instruments, only limited prelaunch scan direction square-wave response (SWR) data were available. Design estimates were modified by convolving in Gaussian blur till the derived LSF/TF's produced SWR's comparable to the measurements. The two MSS instruments were comparable at their temperatures of best focus; separate calculations were performed for bands 1 and 3, band 2 and band 4. The pre-sample nadir effective instantaneous field's of view (EIFOV's) based on the .5 modulation transfer function (MTF) criteria vary from 70 to 75 meters in the track direction and 79 to 82 meters in the scan direction. For the TM instruments more extensive prelaunch measurements were available. Bands 1 to 4, 5 and 7, and 6 were handled separately as were the two instruments. Derived MTF's indicate nadir pre-sample EIFOV's of 32 to 33 meter track (bands 1 to 5, 7) and 36 meter scan (bands 1 to 5, 7) and 1245 meter track (band 6) and 141 meter scan (band 6) for both TM's.

Markham, B. L.

1984-01-01

320

Integrated production overlay field-by-field control for leading edge technology nodes  

NASA Astrophysics Data System (ADS)

As photolithography will continue with 193nm immersion multiple patterning technologies for the leading edge HVM process node, the production overlay requirement for critical layers in logic devices has almost reached the scanner hardware performance limit. To meet the extreme overlay requirements in HVM production environment, this study investigates a new integrated overlay control concept for leading edge technology nodes that combines the run-to-run (R2R) linear or high order control loop, the periodic field-by-field or correction per exposure (CPE) wafer process signature control loop, and the scanner baseline control loop into a single integrated overlay control path through the fab host APC system. The goal is to meet the fab requirements for overlay performance, lower the cost of ownership, and provide freedom of control methodology. In this paper, a detailed implementation of this concept will be discussed, along with some preliminary results.

Chung, Woong Jae; Tristan, John; Gutjahr, Karsten; Subramany, Lokesh; Li, Chen; Sun, Yulei; Yelverton, Mark; Kim, Young Ki; Kim, Jeong Soo; Huang, Chin-Chou Kevin; Pierson, William; Karur-Shanmugam, Ramkumar; Riggs, Brent; Jug, Sven; Robinson, John C.; Yap, Lipkong; Ramanathan, Vidya

2014-04-01

321

Innovative techniques for improving overlay accuracy by using DCM (device correlated metrology) targets as reference  

NASA Astrophysics Data System (ADS)

Overlay metrology performance as Total Measurement Uncertainty (TMU), design rule compatibility, device correlation and measurement accuracy are been challenged at 2x nm node and below. Process impact on overlay metrology becoming critical, and techniques to improve measurement accuracy becomes increasingly important. In this paper, we present an innovative methodology for improving overlay accuracy. A propriety quality metric, Qmerit, is used to identify overlay metrology measurement settings with least process impacts and reliable accuracies. Using the quality metric, an innovative calibration method, ASC (Archer Self Calibration) is then used to remove the inaccuracies. Accuracy validation can be achieved by correlation to reference overlay data from another independent metrology source such as CDSEM data collected on DCM (Device Correlated Metrology) hybrid target or electrical testing. Additionally, reference metrology can also be used to verify which measurement conditions are the most accurate. In this paper we bring an example of such use case.

Tzai, Wei-Jhe; Hsu, Simon C. C.; Chen, Howard; Chen, Charlie; Pai, Yuan Chi; Yu, Chun-Chi; Lin, Chia Ching; Itzkovich, Tal; Yap, Lipkong; Amit, Eran; Tien, David; Huang, Eros; Kuo, Kelly T. L.; Amir, Nuriel

2014-04-01

322

A comparison of the fracture properties of conventional and polymer-modified two-layer asphalt concrete overlay systems  

E-print Network

and different combinations of mixtures, 18 different overlay systems were tested for their fracture toughness. Each overlay was made up of two different layers with asphalt rich sand anti-fracture (SAF) mixture as the bottom layer. Fracture mechanics concepts...

Reddy, Praveena Gutha

2012-06-07

323

Landsat Science: 40 Years of Innovation and Opportunity  

NASA Technical Reports Server (NTRS)

Landsat satellites have provided unparalleled Earth-observing data for nearly 40 years, allowing scientists to describe, monitor and model the global environment during a period of time that has seen dramatic changes in population growth, land use, and climate. The success of the Landsat program can be attributed to well-designed instrument specifications, astute engineering, comprehensive global acquisition and calibration strategies, and innovative scientists who have developed analytical techniques and applications to address a wide range of needs at local to global scales (e.g., crop production, water resource management, human health and environmental quality, urbanization, deforestation and biodiversity). Early Landsat contributions included inventories of natural resources and land cover classification maps, which were initially prepared by a visual interpretation of Landsat imagery. Over time, advances in computer technology facilitated the development of sophisticated image processing algorithms and complex ecosystem modeling, enabling scientists to create accurate, reproducible, and more realistic simulations of biogeochemical processes (e.g., plant production and ecosystem dynamics). Today, the Landsat data archive is freely available for download through the USGS, creating new opportunities for scientists to generate global image datasets, develop new change detection algorithms, and provide products in support of operational programs such as Reducing Emissions from Deforestation and Forest Degradation in Developing Countries (REDD). In particular, the use of dense (approximately annual) time series to characterize both rapid and progressive landscape change has yielded new insights into how the land environment is responding to anthropogenic and natural pressures. The launch of the Landsat Data Continuity Mission (LDCM) satellite in 2012 will continue to propel innovative Landsat science.

Cook, Bruce D.; Irons, James R.; Masek, Jeffrey G.; Loveland, Thomas R.

2012-01-01

324

Colour Separation Overlay and its relation to digital video sampling  

NASA Astrophysics Data System (ADS)

Current techniques for color separation overlay (CSO) are briefly described. The influence of CSO techniques on the formulation of standards for digital video sampling parameters is discussed and experiments are described which investigated the effects on CSO pictures of filtering and sampling the foreground picture signals. The conclusions are that a chrominance (UV) bandwidth of at least 3 MHz, (implying a sampling frequency of at least 6 MHz) is needed for satisfactory CSO whereas luminance (Y) sampling frequency need not be constrained by CSO considerations. Hence a YUV sampling frequency standard of 13.5, 6.75, 6.75 MHz appears to be commensurate with good-quality CSO. This investigation into digital video sampling parameters formed part of the evidence on which the 13.5:6.75:6.75 system was chosen for digital video sampling.

Oliphant, A.

1982-06-01

325

Complete Imageless solution for overlay front-end manufacturing  

NASA Astrophysics Data System (ADS)

Imageless option of KLA-Tencor RDM system (Recipe Data Management) is a new method of recipe creation, using only the mask design to define alignment target and measurement parameters. This technique is potentially the easiest tool to improve recipe management of a large amount of products in logic fab. Overlay recipes are created without wafer, by using a synthetic image (copy of gds mask file) for alignment pattern and target design like shape (frame in frame) and size for the measurement. A complete gauge study on critical CMOS 90nm Gate level has been conducted to evaluate reliability and robustness of the imageless recipe. We show that Imageless limits drastically the number of templates used for recipe creation, and improves or maintains measurement capability compare to manual recipe creation (operator dependant). Imageless appears to be a suitable solution for high volume manufacturing, as shown by the results obtained on production lots.

Herisson, David; LeCacheux, Virginie; Touchet, Mathieu; Vachellerie, Vincent; Lecarpentier, Laurent; Felten, Franck; Polli, Marco

2005-09-01

326

Implementing IPv6 as a Peer-to-Peer Overlay Network Lidong Zhou Robbert van Renesse Michael Marsh  

E-print Network

Implementing IPv6 as a Peer-to-Peer Overlay Network Lidong Zhou Robbert van Renesse Michael Marsh,rvr,mmarsh}@cs.cornell.edu Abstract This paper proposes to implement an IPv6 routing in- frastructure as a self-organizing overlay network on top of the current IPv4 infrastructure. The overlay network builds upon a distributed IPv6 edge

Birman, Kenneth P.

327

Bridging the Divide: Translating Landsat Research Into Usable Science  

NASA Astrophysics Data System (ADS)

Science has long served humankind. Breakthroughs in medicine have increased longevity and advances in technology have made modern-day conveniences possible. Yet, social benefits begotten by the environmental sciences, although critical for the survival of humanity, have not always been as widely recognized or used. To benefit today's rapidly growing population, the divides between environmental research, applied environmental science, and use of this information by decision makers must be bridged. Lessons about the translation from research to usable science can be learned from the four decades of Landsat history, and these lessons can serve as useful models for bridging the gaps between new technology, scientific research, and the use of that research and technology in real-world problem solving. In 1965, William Pecora, then-director of the U.S. Geological Survey, proposed the idea of a remote sensing satellite program to gather facts about natural resources of Earth. For the next seven years, an intense campaign showing the depth and diversity of satellite imagery applications was waged. This led to the 1972 launch of the first civilian land-observing satellite, Landsat 1. By 1975, successful application research based on Landsat 1 imagery prompted then-NASA Administrator Dr. James Fletcher to proclaim that if one space age development would save the world, it would be Landsat and its successor satellites. Thirty-four years of continual Landsat imaging and related-research has lead to the implementation of many socially beneficial applications, such as improved water management techniques, crop insurance fraud reduction, illicit crop inventories, natural disaster relief planning, continent-scale carbon estimates, and extensive cartographic advances. Despite these successes, the challenge of translating Landsat research into realized social benefits remains. Even in this geospatially-savvy era, the utility of Landsat largely escapes policymakers. Here, in an effort to better understand these challenges, we dissect the anatomy of some of Landsat's social benefit success stories and draw on the advice of Landsat experts to outline some of the important steps needed to facilitate the recognition of usable environmental science.

Rocchio, L. E.; Davis, A. L.

2006-12-01

328

Subsetting and Formatting Landsat-7 LOR ETM+ and Data Products  

NASA Technical Reports Server (NTRS)

The Landsat-7 Processing System (LPS) processes Landsat-7 Enhanced Thematic Mapper (ETM+) instrument data into large, contiguous segments called "subintervals" and stores them in Level OR (LOR) data files. The LPS processed subinterval products must be subsetted and reformatted before the Level I processing systems can ingest them. The initial full subintervals produced by the LPS are stored mainly in HDF Earth Observing System (HDF-EOS) format which is an extension to the Hierarchical Data Format (HDF). The final LOR products are stored in native HDF format. Primarily the EOS Core System (ECS) and alternately the DAAC Emergency System (DES) subset the subinterval data for the operational Landsat-7 data processing systems. The HDF and HDF-EOS application programming interfaces (APIs) can be used for extensive data subsetting and data reorganization. A stand-alone subsetter tool has been developed which is based on some of the DES code. This tool makes use of the HDF and HDFEOS APIs to perform Landsat-7 LOR product subsetting and demonstrates how HDF and HDFEOS can be used for creating various configurations of full LOR products. How these APIs can be used to efficiently subset, format, and organize Landsat-7 LOR data as demonstrated by the subsetter tool and the DES is discussed.

Reid, Michael R.

2000-01-01

329

Upper Klamath Basin Landsat Image for April 30, 2004: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

330

Upper Klamath Basin Landsat Image for April 29, 2006: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

331

Upper Klamath Basin Landsat Image for August 29, 2004: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

332

Upper Klamath Basin Landsat Image for July 28, 2004: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

333

Upper Klamath Basin Landsat Image for September 21, 2004: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

334

Upper Klamath Basin Landsat Image for August 4, 2004: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

335

Upper Klamath Basin Landsat Image for October 7, 2004: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

336

Upper Klamath Basin Landsat Image for July 2, 2006: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

337

Upper Klamath Basin Landsat Image for June 23, 2006: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

338

Upper Klamath Basin Landsat Image for June 26, 2004: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

339

Upper Klamath Basin Landsat Image for June 1, 2004: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

340

Upper Klamath Basin Landsat Image for July 12, 2004: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

341

Upper Klamath Basin Landsat Image for June 16, 2006: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

342

Upper Klamath Basin Landsat Image for October 22, 2006: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

343

Upper Klamath Basin Landsat Image for August 19, 2006: Path 44 Row 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

344

Upper Klamath Basin Landsat Image for September 30, 2004: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

345

Upper Klamath Basin Landsat Image for September 20, 2006: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

346

Upper Klamath Basin Landsat Image for September 27, 2006: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

347

Upper Klamath Basin Landsat Image for July 25, 2006: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

348

Upper Klamath Basin Landsat Image for June 17, 2004: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

349

Upper Klamath Basin Landsat Image for May 25, 2004: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

350

Upper Klamath Basin Landsat Image for October 16, 2004: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

351

Upper Klamath Basin Landsat Image for July 18, 2006: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

352

Upper Klamath Basin Landsat Image for April 7, 2004: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

353

Upper Klamath Basin Landsat Image for November 8, 2004: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

354

Upper Klamath Basin Landsat Image for October 29, 2006: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

355

Upper Klamath Basin Landsat Image for August 19, 2006: Path 44 Row 31  

USGS Publications Warehouse

This subset of a Landsat-5 image shows part of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

356

Upper Klamath Basin Landsat Image for July 9, 2006: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

357

Upper Klamath Basin Landsat Image for May 6, 2006: Path 45 Rows 30 and 31  

USGS Publications Warehouse

This image is a mosaic of Landsat-5 images of the upper Klamath Basin. The original images were obtained from the U.S. Geological Survey Earth Resources Observation and Science Center (EROS). EROS is responsible for archive management and distribution of Landsat data products. The Landsat-5 satellite is part of an ongoing mission to provide quality remote sensing data in support of research and applications activities. The launch of Landsat-5 on March 1, 1984 marks the addition of the fifth satellite to the Landsat series. The Landsat-5 satellite carries the Thematic Mapper (TM) sensor. More information on the Landsat program can be found online at http://landsat.usgs.gov/.

Snyder, Daniel T.

2012-01-01

358

Urban change detection procedures using Landsat digital data  

NASA Technical Reports Server (NTRS)

Landsat multispectral scanner data was applied to an urban change detection problem in Denver, CO. A dichotomous key yielding ten stages of residential development at the urban fringe was developed. This heuristic model allowed one to identify certain stages of development which are difficult to detect when performing digital change detection using Landsat data. The stages of development were evaluated in terms of their spectral and derived textural characteristics. Landsat band 5 (0.6-0.7 micron) and texture data produced change detection maps which were approximately 81 percent accurate. Results indicated that the stage of development and the spectral/textural features affect the change in the spectral values used for change detection. These preliminary findings will hopefully prove valuable for improved change detection at the urban fringe.

Jensen, J. R.; Toll, D. L.

1982-01-01

359

Investigation of mesoscale cloud features viewed by LANDSAT  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. Some 50 LANDSAT images displaying mesoscale cloud features were analyzed. This analysis was based on the Rayleigh-Kuettner model describing the formation of that type of mesoscale cloud feature. This model lends itself to computation of the average wind speed in northerly flow from the dimensions of the cloud band configurations measured from a LANDSAT image. In nearly every case, necessary conditions of a curved wind profile and orientation of the cloud streets within 20 degrees of the direction of the mean wind in the convective layer were met. Verification of the results by direct observation was hampered, however, by the incompatibility of the resolution of conventional rawinsonde observations with the scale of the banded cloud patterns measured from LANDSAT data. Comparison seems to be somewhat better in northerly flows than in southerly flows, with the largest discrepancies in wind speed being within 8m/sec, or a factor of two.

Sherr, P. E. (principal investigator); Feteris, P. J.; Lisa, A. S.; Bowley, C. J.; Fowler, M. G.; Barnes, J. C.

1976-01-01

360

Two-way communication and analysis program on LANDSAT  

NASA Technical Reports Server (NTRS)

Community workshops, field visits, telephone surveys, and other research reveals that professionals at the substate level are interested in and open to consideration of LANDSAT as a planning and resource management tool, but are at the same time skeptical about some of the inherent problems with LANDSAT such as cost, resolution, frequency of coverage, and data continuity. The principal requirements for increasing the utilization of LANDSAT by potential substate users were identified and documented. Without a committment from the Federal Government for increased substrate utilization and the availability of trained professionals to meet the needs of a largely new user community, substrate activity is likely to remain at a minimum. Well conceived and well executed demonstration projects could play a critical role is shaping the technology's ability to be more sensitive to substate user needs and interests as well as validating the effectiveness of this data to a skeptical audience.

1983-01-01

361

BRAVO economic study of LANDSAT follow-on  

NASA Technical Reports Server (NTRS)

The LANDSAT Follow-On satellite consists of two major systems: the instrument module and the Multi-Mission Modular Spacecraft (MMS). The instrument module contains the thematic mapper and the five-band multispectral scanner instruments. The instrument module also includes the solar array, the tracking and data relay satellite (TDRS) antenna, and the wideband data module. The MMS contains the modularized and standardized power, propulsion, attitude control, and command and data handling subsystems. The Shuttle will be supporting the LANDSAT Follow-On system. The LANDSAT Follow-On Project plans two Delta 3910 launches. The first is scheduled for 1981; the second Delta launch will occur as needed to keep one satellite operational on orbit. The second satellite will be ready six months after the first. It could be launched any time after that. Shuttle support of the system could begin in early 1983 but would be scheduled to start after the second Delta launch.

Pritchard, E. I.; Blake, R. T.; Plough, J. A.; Mead, O. J.; Dawson, J. J.

1977-01-01

362

Impact of LANDSAT MSS sensor differences on change detection analysis  

NASA Technical Reports Server (NTRS)

Some 512 by 512 pixel subwindows for simultaneously acquired scene pairs obtained by LANDSAT 2,3 and 4 multispectral band scanners were coregistered using LANDSAT 4 scenes as the base to which the other images were registered. Scattergrams between the coregistered scenes (a form of contingency analysis) were used to radiometrically compare data from the various sensors. Mode values were derived and used to visually fit a linear regression. Root mean square errors of the registration varied between .1 and 1.5 pixels. There appear to be no major problem preventing the use of LANDSAT 4 MSS with previous MSS sensors for change detection, provided the noise interference can be removed or minimized. Data normalizations for change detection should be based on the data rather than solely on calibration information. This allows simultaneous normalization of the atmosphere as well as the radiometry.

Likens, W. C.; Wrigley, R. C.

1983-01-01

363

Spatial and spectral simulation of LANDSAT images of agricultural areas  

NASA Technical Reports Server (NTRS)

A LANDSAT scene simulation capability was developed to study the effects of small fields and misregistration on LANDSAT-based crop proportion estimation procedures. The simulation employs a pattern of ground polygons each with a crop ID, planting date, and scale factor. Historical greenness/brightness crop development profiles generate the mean signal values for each polygon. Historical within-field covariances add texture to pixels in each polygon. The planting dates and scale factors create between-field/within-crop variation. Between field and crop variation is achieved by the above and crop profile differences. The LANDSAT point spread function is used to add correlation between nearby pixels. The next effect of the point spread function is to blur the image. Mixed pixels and misregistration are also simulated.

Pont, W. F., Jr. (principal investigator)

1982-01-01

364

Spatial and spectral simulation of Landsat images of agricultural areas  

NASA Technical Reports Server (NTRS)

A Landsat scene simulation capability was developed to study the effects of small fields and misregistration on Landsat-based crop proportion estimation procedures. The simulation employs a pattern of ground polygons each with a crop ID, planting date, and scale factor. Historical greenness/brightness crop development profiles generate the mean signal values for each polygon. Historical within-field covariances add texture to pixels in each polygon. The planting dates and scale factors create between-field/within-crop variation. Between field and crop variation is achieved by the above and crop profile differences. The Landsat point spread function is used to add correlation between nearby pixels. The next effect of the point spread function is to blur the image. Mixed pixels and misregistration are also simulated. Previously announced in STAR as N82-32813

Pont, W. F., Jr.

1982-01-01

365

Prototyping Global Web Enabled Landsat Data Production, Distribution and Visualization  

NASA Astrophysics Data System (ADS)

The NASA funded Web-enabled Landsat Data (WELD) project is systematically generating 30m weekly, seasonal, monthly and annual composited Landsat mosaics of the conterminous United States and Alaska (http://weld.cr.usgs.gov/). The WELD products provide consistent data that are starting to be used for land management applications and to derive land cover as well as geophysical and biophysical products for assessment of surface dynamics and to study Earth system functioning. This paper describes the challenges in expanding this production and internet distribution and visualization to global scale. At global scale, the volume of Landsat data and the number of files become so large that they are awkward to work and become a type of "Big Data" although the products are sufficiently well structured for their management using database management tools. Prototyping efforts running a global version of the WELD code on the NASA Earth Exchange (NEX) high-performance supercomputing platform are presented. Global monthly WELD products generated in the Sinusoidal Projection in tiles nested to the MODIS Land product tiling scheme are illustrated and an intuitive what you see is what you get (WYSIWYG) global WELD product Internet distribution and visualization interface is showcased. The global availability of cloud-free Landsat Enhanced Thematic Mapper Plus (ETM+) and Thematic Mapper (TM) data and the monthly global probability of acquiring a cloud-free land surface observation for the two instruments independently and fused together are reported with recommendations for global Landsat processing of the 30m U.S. Landsat archive back to 1982.

Roy, D. P.; Kommareddy, I.; Kovalskyy, V.; Votava, P.; Nemani, R. R.; Ju, J.

2012-12-01

366

Deforestation planning for cattle grazing in Amazon Basin using LANDSAT data  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. This research did not show the total potential of the LANDSAT system, but tried to open up new research aspects for the utilization of LANDSAT data in natural resource control. Results obtained through this research showed that LANDSAT data can be used to develop monitoring programs in the tropical forest areas of Brazil.

Dejesusparada, N. (principal investigator); Dossantos, A. P.; Demoraisnovo, E. M. L.

1978-01-01

367

Calibration of Landsat thermal data and application to water resource studies  

Microsoft Academic Search

The newest in the Landsat series of satellites was launched April 15, 1999. The imagery collected by Landsat is used for a myriad of applications, from coral reef studies to land management. In order to take advantage of Landsat 7 data, the Enhanced Thematic Mapper+ (ETM+) instrument must be calibrated. This study focuses on the immediate postlaunch calibration verification of

John R. Schott; Julia A. Barsi; Bryce L. Nordgren; Nina Gibson Raqueño; Dilkushi de Alwis

2001-01-01

368

Overlayers on silver nanotriangles: Field confinement and spectral position of localized surface plasmon resonances.  

PubMed

We studied the spectral evolution of plasmon modes associated with silver nanotriangles as a function of dielectric overlayer thickness in the range of 5-300 nm. A substantial red-shift of the resonance is observed that oscillates with increasing over-layer thickness. We explain this previously unreported oscillation through the cavity quantum electrodynamical effect of the array of triangles combined with the dielectric overlayer. The red-shift, though substantial, is less than expected. Comparison with numerical models indicates that this discrepancy is due to very tight field confinement around the tips of the triangles. PMID:16895372

Murray, W Andrew; Suckling, James R; Barnes, William L

2006-08-01

369

Prosthodontic management of worn dentition in pediatric patient with complete overlay dentures: a case report.  

PubMed

Overlay complete dentures are simple, reversible and economical treatment modality for patients with congenital or acquired disorders that severely affect the tooth development. It satisfies both the esthetic and functional demands where the extraction of teeth is not generally indicated. In pediatric patients, the overlay dentures establish a relatively stable occlusion that improves patient's tolerance to the future treatment procedures for worn dentition. This clinical report highlights the imperative need of appropriate treatment strategy and application of maxillary and mandibular overlay dentures in a pediatric patient who suffered from congenitally mutilated and worn dentition. PMID:23236577

Kumar, Prince; Rastogi, Jyoti; Jain, Chandni; Singh, Harkanwal Preet

2012-11-01

370

LANDSAT-D data format control book. Volume 2: Telemetry  

NASA Technical Reports Server (NTRS)

The formats used for the transmission of LANDSAT-D and LANDSAT-D Prime spacecraft telemetry data through either the TDRS/GSTDN via the NASCOM Network to the CSF are described as well as the telemetry flow from the command and data handling subsystem, a telemetry list and telemetry matrix assignment for the mission and engineering formats. The on-board computer (OBC) controlled format and the dwell format are also discussed. The OBCs contribution to telemetry, and the format of the reports, are covered. The high rate data channel includes the payload correction data format, the narrowband tape recorder and the OBC dump formats.

Talipsky, R.

1982-01-01

371

An Illumination Correction ALgorithm on Landsat-TM Data  

NASA Technical Reports Server (NTRS)

In this paper, a new illumination correction model, the rotation model, is introduced. The model is based on the empirical correlation between reflectance and the illumination condition (IL). The model eliminates the dependency of reflectance on IL through rotating the data in IL-reflectance space. This model is compared with widely used cosine model and C model over a sample forest region. We found that the newly developed rotation model consistently performs best on both atmospheric uncorrected and corrected Landsat images. Index Terms Landsat, illumination correction, change detection, LEDAPS

Tan, Bin; Wolfe, Robert; Masek, Jeffrey; Gao, Feng; Vermote, Eric F.

2010-01-01

372

LANDSAT-D ground segment operations plan, revision A  

NASA Technical Reports Server (NTRS)

The basic concept for the utilization of LANDSAT ground processing resources is described. Only the steady state activities that support normal ground processing are addressed. This ground segment operations plan covers all processing of the multispectral scanner and the processing of thematic mapper through data acquisition and payload correction data generation for the LANDSAT 4 mission. The capabilities embedded in the hardware and software elements are presented from an operations viewpoint. The personnel assignments associated with each functional process and the mechanisms available for controlling the overall data flow are identified.

Evans, B.

1982-01-01

373

Landsat change detection can aid in water quality monitoring  

NASA Technical Reports Server (NTRS)

Comparison between Landsat-1 and -2 imagery of Arkansas provided evidence of significant land use changes during the 1972-75 time period. Analysis of Arkansas historical water quality information has shown conclusively that whereas point source pollution generally can be detected by use of water quality data collected by state and federal agencies, sampling methodologies for nonpoint source contamination attributable to surface runoff are totally inadequate. The expensive undertaking of monitoring all nonpoint sources for numerous watersheds can be lessened by implementing Landsat change detection analyses.

Macdonald, H. C.; Steele, K. F.; Waite, W. P.; Shinn, M. R.

1977-01-01

374

Assessment of LANDSAT for rangeland mapping, Rush Valley, Utah  

NASA Technical Reports Server (NTRS)

The feasibility of using LANDSAT MSS (multispectral scanner) data to identify and map cover types for rangeland, and to determine comparative condition of the ecotypes was assessed. A supporting objective is to assess the utility of various forms of aerial photography in the process. If rangelands can be efficiently mapped with Landsat data, as supported by appropriate aerial photography and field data, then uniform standards of cover classification and condition may be applied across the rangelands of the state. Further, a foundation may be established for long-term monitoring of range trend, using the same satellite system over time.

Ridd, M. K.; Price, K. P.; Douglass, G. E.

1984-01-01

375

Mapping wetland and forest landscapes in Siberia with Landsat data  

NASA Astrophysics Data System (ADS)

Landsat data availability provides opportunity for improving the knowledge of the Siberian ecosystems necessary for quantifying the response of the regional carbon cycle to the climate change. We developed a new wetland map based on Landsat data for whole West Siberia aiming at scaling up the methane emission observations. Mid-summer Landsat scenes were used in supervised classification method, based on ground truth data obtained during multiple field surveys. The method allows distinguishing following wetland types: pine-dwarf shrubs-sphagnum bogs or ryams, ridge-hollows complexes, shallow-water complexes, sedge-sphagnum poor fens, herbaceous-sphagnum poor fens, sedge-(moss) poor fens and fens, wooded swamps or sogra, palsa complexes. In our estimates wetlands cover 36% of the taiga area. Total methane emission from WS taiga mires is estimated as 3.6 TgC/yr,which is 77% larger as compared to the earlier estimate based on partial Landsat mapping combined with low resolution map due to higher fraction of fen area. We make an attempt to develop a forest typology system useful for a dynamic vegetation modeling and apply it to the analysis of the forest type distribution for several test areas in West and East Siberia, aiming at capability of mapping whole Siberian forests based on Landsat data. Test region locations are: two in West Siberian middle taiga (Laryegan and Nyagan), and one in East Siberia near Yakutsk. The ground truth data are based on analysis of the field survey, forest inventory data from the point of view of the successional forest type classification. Supervised classification was applied to the areas where ample ground truth and inventory data are available, using several limited area maps and vegetation survey. In Laryegan basin the upland forest areas are dominated (as climax forest species) by Scots pine on sandy soils and Siberian pine with presence of fir and spruce on the others. Those types are separable using Landsat spectral data alone. In the permafrost area around Yakutsk the most widespread succession type is birch to larch succession. Three stages of the birch to larch succession are detectable from Landsat image. When Landsat data is used in both West and East Siberia, distinction between deciduous broad-leaved species (birch, aspen, and willow) is difficult due to similarity in spectral signatures. Same problem exists for distinguishing between dark coniferous species (Siberian pine, fir and spruce). Forest classification can be improved by applying landscape type analysis, such as separation into floodplain, terrace, sloping hills.

Maksyutov, Shamil; Kleptsova, Irina; Glagolev, Mikhail; Sedykh, Vladimir; Kuzmenko, Ekaterina; Silaev, Anton; Frolov, Alexander; Nikolaeva, Svetlana; Fedorov, Alexander

2014-05-01

376

Improved diffraction-based overlay metrology by use of two dimensional array target  

NASA Astrophysics Data System (ADS)

We report results of theoretical modeling into a scatterometry-based method relevant to overlay measurement. A set of two array targets were designed with intentional offsets difference, d and d+20 nm, between the top and bottom grid arrays along the X and Y directions. The correlation of bi-azimuth measurements is the first critical issue been taken into account. The method linearizes the differential values of scatterometry signatures at the first diffraction order with respect to designed offsets, and hence permits determination of overlay using a classical linear method. By evaluating the process variations (eg. CD, roundness and thickness) on overlay measurement error, a set of two overlay target design were optimized to minimize the correlation of bi-azimuth measurements and maximize the measurement sensitivity.

Ku, Yi-Sha; Pang, Hsiu-Lan; Hsu, Weite; Shyu, Deh-Ming

2009-08-01

377

Patterning of Heteroepitaxial Overlayers from Nano to Micron Scales K. R. Elder,1,* G. Rossi,2  

E-print Network

Patterning of Heteroepitaxial Overlayers from Nano to Micron Scales K. R. Elder,1,* G. Rossi,2 P dimension- ality of the surface is the only driving force leading to surface reconstruction. More often

Elder, Ken

378

A program to design asphalt concrete overlays to mitigate reflection cracking  

E-print Network

"Reflection Crack". Reinforcing grids reduce the amount of water that enters the sublayers of a pavement by reinforcing the overlay. The appearance of a reflection crack is delayed, and reinforcing the pavement reduces the width of the crack that develops...

Satyanarayana Rao, Sindhu

2012-06-07

379

Radio-over-fiber distribution using an optical millimeter-wave\\/DWDM overlay  

Microsoft Academic Search

We demonstrate an optical MM-wave\\/DWDM overlay using optical suppressed-carrier modulation to simultaneously upconvert multi-wavelength subcarriers to 35 GHz. Performance of the system is analyzed for radio-over-fiber distribution

R. A. Griffin; J. J. O'Reilly

1999-01-01

380

Informed Content Delivery Across Adaptive Overlay byers@cs.bu.edu  

E-print Network

Considine jconsidi@cs.bu.edu Michael Mitzenmacher michaelm@eecs.harvard.edu Stanislav Rost stanrost they complement existing overlay network architectures. #3; John Byers, Jeffrey Considine and Stanislav Rost were

Byers, John W.

381

Informed Content Delivery Across Adaptive Overlay byers@cs.bu.edu  

E-print Network

Considine jconsidi@cs.bu.edu Michael Mitzenmacher michaelm@eecs.harvard.edu Stanislav Rost stanrost they complement existing overlay network architectures. John Byers, Jeffrey Considine and Stanislav Rost were sup

Mitzenmacher, Michael

382

Ultrasonic Evaluation of Two Dissimilar Metal Weld Overlay Specimens  

SciTech Connect

Two dissimilar metal weld (DMW) pipe-to-nozzle specimens were implanted with thermal fatigue cracks in the 13% to 90% through-wall depth range. The specimens were ultrasonically evaluated with phased-array probes having center frequencies of 0.8, 1.0, 1.5, and 2.0 megahertz (MHz). An Alloy 82/182 weld overlay (WOL) was applied and the specimens were ultrasonically re-evaluated for flaw detection and characterization. The Post-WOL flaw depths were approximately 10% to 56% through-wall. This study has shown the effectiveness of ultrasonic examinations of Alloy 82/182 overlaid DMW specimens. Phased-array probes with center frequency in the 0.8- to 1.0-MHz range provide a strong coherent signal but the greater ultrasonic wavelength and larger beam spot size prevent the reliable detection of small flaws. These small flaws had nominal through-wall depths of less than 15% and length in the 50-60 mm (2-2.4 in.) range. Flaws in the 19% and greater through-wall depth range were readily detected with all four probes. At the higher frequencies, the reflected signals are less coherent but still provide adequate signal for flaw detection and characterization. A single inspection at 2.0 MHz could provide adequate detection and sizing information but a supplemental inspection at 1.0 or 1.5 MHz is recommended.

Crawford, Susan L.; Cinson, Anthony D.; Prowant, Matthew S.; Moran, Traci L.; Anderson, Michael T.

2012-06-30

383

Design of a synthetic vision overlay for UAV autoland monitoring  

NASA Astrophysics Data System (ADS)

For Unmanned Aerial Vehicles (UAVs), autonomous forms of autoland are being pursued that do not depend on special, deployability restraining, ground-based equipment for the generation of the reference path to the runway. Typically, these forms of autoland use runway location data from an onboard database to generate the reference path to the desired location. Synthetic Vision (SV) technology provides the opportunity to use conformally integrated guidance reference data to 'anchor' the goals of such an autoland system into the imagery of the nose-mounted camera. A potential use of this is to support the operator in determining whether the vehicle is flying towards the right location in the real world, e.g., the desired touchdown position on the runway. Standard conformally integrated symbology, representing e.g., the future pathway and runway boundaries, supports conformance monitoring and detection of latent positioning errors. Additional integration of landing performance criteria into the symbology supports assessment of the severity of these errors, further aiding the operator in the decision whether the automated landing should be allowed to continue or not. This paper presents the design and implementation of an SV overlay for UAV autoland procedures that is intended for conformance and integrity monitoring during final approach. It provides preview of mode changes and decision points and it supports the operator in assessing the integrity of the used guidance solution.

Tadema, Jochum; Theunissen, Eric

2008-04-01

384

Support surfaces: beds, mattresses, overlays-oh my!  

PubMed

The prevention and treatment of pressure ulcers are major concerns for health care providers across the care continuum. The selection of a support surface is an important component of a comprehensive pressure ulcer prevention program. The accepted standard in clinical practice for pre-venting pressure ulcers and other complications of immobility is to either turn patients manually at frequent intervals or to use a pressure-reducing device. The longer a patient is immobilized, the more profound will be the systemic complications. The costs associated with the complications of immobility are staggering in terms of human suffering, physiologic damage,and real dollars. A variety of specialty beds, mattresses, and overlays have been designed to address pressure, shear, friction, and moisture. Limited data exist regarding the efficacy of these products. Clinicians want to choose a support surface for their patients on the basis of product performance. With the push toward establishing standards for testing methods and reporting information, clinicians can look forward to making support surface decisions based on the evidence and outcome data resulting from controlled clinical studies and expert opinion and consensus. PMID:15924893

Mackey, Dianne

2005-06-01

385

The Thermal Infrared Sensor on the Landsat Data Continuity Mission  

Microsoft Academic Search

The Landsat Data Continuity Mission (LDCM), a joint NASA and USGS mission, is scheduled for launch in December, 2012. The LDCM instrument payload will consist of the Operational Land Imager (OLI), provided by Ball Aerospace and Technology Corporation (BATC) under contract to NASA and the Thermal Infrared Sensor (TIRS), provided by NASA's Goddard Space Flight Center (GSFC). This paper outlines

Dennis Reuter; Cathy Richardson; James Irons; Rick Allen; Martha Anderson; Jason Budinoff; Gordon Casto; Craig Coltharp; Paul Finneran; Betsy Forsbacka; Taylor Hale; Tom Jennings; Murzy Jhabvala; Allen Lunsford; Greg Magnuson; Rick Mills; Tony Morse; Veronica Otero; Scott Rohrbach; Ramsey Smith; Terry Sullivan; Zelalem Tesfaye; Kurtis J. Thome; Glenn Unger; Paul Whitehouse

2010-01-01

386

Impact of LANDSAT MSS Sensor Differences on Change Detection Analysis  

NASA Technical Reports Server (NTRS)

Change detection techniques were used to pinpoint differences in the multispectral band scanners on LANDSAT 2, 3, and 4 satellites. The method of analysis was to co-register 512 by 512 pixel subwindows for all data pairs followed by scattergram generation and analysis. In all cases, the LANDSAT-4 data were used as the base to which other images were registered. There appear to be no major problems preventing use of LANDSAT-4 MSS with previous MSS sensors for charge detection, provided the interference noise can be removed or minimized. This noise may result in detection of spurious changes, as well as affect other uses of the data, including image classification. Analysis of dark (water and forests), rather than light features will be most impacted because the noise will form a higher percentage of the total response at low DN values. Any data normalizations for change detection should be based upon the data, rather than solely upon calibration information. While the observed relative radiometric transfer function between LANDSAT 3 and 4 was approximately as predicted, there were still significant deviations. Normalizing based upon data content also can have the advantage of allowing simultaneous normalization of the atmosphere as well as the radiometry.

Likens, W. C.; Wrigley, R. C.

1984-01-01

387

Investigation of several aspects of LANDSAT-4 data quality  

NASA Technical Reports Server (NTRS)

No insurmountable problems in change detection analysis were found when portions of scenes collected simultaneously by LANDSAT 4 MSS and either LANDSAT 2 or 3. The cause of the periodic noise in LANDSAT 4 MSS images which had a RMS value of approximately 2DN should be corrected in the LANDSAT D instrument before its launch. Analysis of the P-tape of the Arkansas scene shows bands within the same focal plane very well registered except for the thermal band which was misregistered by approximately three 28.5 meter pixels in both directions. It is possible to derive tight confidence bounds for the registration errors. Preliminary analyses of the Sacramento and Arkansas scenes reveals a very high degree of consistency with earlier results for bands 3 vs 1, 3 vs 4, and 3 vs 5. Results are presented in table form. It is suggested that attention be given to the standard deviations of registrations errors to judge whether or not they will be within specification once any known mean registration errors are corrected. Techniques used for MTF analysis of a Washington scene produced noisy results.

Wrigley, R. C. (principal investigator)

1983-01-01

388

Exploitation of Landsat imagery and ancillary data for battlespace characterization  

Microsoft Academic Search

Spectral data provide opportunities to discriminate targets from background clutter and to detect partially concealed objects. However, data with high spatial resolution generally are not synoptic scale (hundreds of kilometers). By analyzing courser resolution synoptic imagery, high-resolution sensors can then be cued to areas of potential targets. Multispectral images (Landsat 7) are combined with ancillary data-lines of communication, digital elevation

Seth M. Orloff; Su May Hsu; H.-H. K. Burke

2002-01-01

389

Mapping of coastal-water turbidity using LANDSAT imagery  

Microsoft Academic Search

Secchi disk depth was recorded in the field all along the Swedish coastline and compared with LANDSAT data. Chromaticity analysis was applied in the evaluation to allow for Sun angle and atmospheric corrections. The data were used to study the relative nutrient and solids loading situations around the Swedish coast and as a basis for the applicability of laser bathymetry

L. T. Lindell; O. Steinvall; M. Jonsson; Th. Claesson

1985-01-01

390

Multispectral data restoration study. [digital correction of LANDSAT geographic data  

NASA Technical Reports Server (NTRS)

A digital resampling technique for LANDSAT data is reported that incorporates a deconvolution concept to minimize spatial and radiometric degradation of data during resampling for geometric correction. A quantitative comparison of cubic convolution and digital restoration methods establishes the latter as the superior technique.

Shah, N. J.; Wilson, C. L.

1977-01-01

391

Landsat 7 Images Show Scale of Tsunami Damage  

NSDL National Science Digital Library

This NASA page shows before and after pictures taken by Landsat 7's Enhanced Thematic Mapper Plus (ETM+) instrument of a part of the coast of Sumatra, Indonesia. The images show that the scale of the tsunami's impact can be seen from space.

Nasa

392

Prospecting in glaciated terrain-integrating airborne and Landsat MSS  

NASA Astrophysics Data System (ADS)

The effects of a glacially enriched zone of trace elements on soils and vegetation in the Thetford Mines area of Quebec were investigated using ground information plus digital Multispectral Scanner (MSS) data from airborne and Landsat sensors. The enriched zone was developed during the last glaciation when a southeastward flowing glacier eroded and dispersed an ultrabasic outcrop that had anomalous levels of Ni, Cu, Co, Cr, Mg and Fe. The dispersal train of enriched trace elements was detectable over an area at least 70 × 15 km `down-ice' from the outcrop. In this zone total Ni concentrations in the soil ranged from background levels of 10 ppm to levels in excess of 1800 ppm. The dominant tree species, Abies balsamea (balsam fir) and Picea glauca (white spruce) reflect the soil anomaly with higher concentrations of trace elements in their tissue and lower concentrations of chlorophyll. An unsupervised enhancement of Landsat imagery showed that a tonal discontinuity was caused by a vegetation segregation related to the heavy metal enrichment soils. A detailed study based on Landsat MSS data was able to establish regional patterns of chlorophyll production by certain plant species closely related to the ultrabasic dispersal train. Multi-channel airborne MSS data confirmed the Landsat soil-plant patterns.

Belanger, J. R.; Rencz, A. N.

393

LANDSAT menhaden and thread herring resources investigation, Gulf of Mexico  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. The most significant achievements thus far include the successful charting of high probability fishing areas from LANDSAT MSS data and the successful simulation of an operational satellite system to provide tactical information for the commercial harvest of menhaden.

Savastano, K. (principal investigator); Kemmerer, A. J.; Leming, T.; Holley, H.; Faller, K. H.

1976-01-01

394

Quantifying Changes in the Land Over Time with Landsat  

NSDL National Science Digital Library

In this lesson, students analyze land cover change in order to help them grasp the extent, significance, and consequences of land cover change; and to introduce them to the perspective of space-based Earth observations. Students learn to identify kinds of land cover (such as roads, fields, urban areas, and lakes) in Landsat satellite images. They decide which land cover types allow the passage of water into the soil (pervious) and which types do not allow it (impervious). They consider some effects of increasing impervious surface area on ecosystem health. Students then make land cover maps using two Landsat satellite images taken about a decade apart, and quantify the change of land cover from pervious to impervious surface. They also make predictive maps of what they think the nature and extent of land cover change in the area will be in the year 2025, and speculate about the consequences for the availability of water for people and ecosystems. Students justify in writing their predictive maps and their thoughts about the consequences of change. This activity uses Landsat images of Phoenix, Arizona; links are also provided for finding Landsat images of other cities.

395

Oil Spill in the Gulf of Mexico - Landsat 7  

USGS Multimedia Gallery

On April 20, 2010, an explosion at an oil well in the Gulf of Mexico resulted in a major oil spill. Since then, emergency response efforts have been underway to contain the growing oil slick before it reaches the southern coast of the United States. Landsat imagery, acquired by the U.S. Geological ...

2010-05-05

396

Educator's Guide for Mission to Earth: LANDSAT Views the World  

NASA Technical Reports Server (NTRS)

This teacher's guide is specifically designed to provide information and suggestions for using LANDSAT imagery to teach basic concepts in several content areas. Content areas include: (1) Earth science and geology; (2) environmental studies; (3) geography; and (4) social and urban studies.

Tindal, M. A.

1978-01-01

397

The availability of Landsat data: Past, present, and future  

USGS Publications Warehouse

It has long been recognized that the success of the Landsat program would depend on an effective distribution of its data to a wide variety of users, worldwide, in a timely manner. Since 1972, nearly $250 million worth of data have been distributed by a network of ground stations around the world. The policies of the U.S. Government affecting the distribution, availability, and pricing of Landsat data have been controversial, and have been strongly affected by the attempts to commercialize the program. At the present time, data are being distributed in the U.S. by either government or commercial entities, depending on the date of acquisition of the data in question and whether or not the customer is affiliated with the Federal Government. Although the future distribution of Landsat data is currently under discussion, it seems likely that data distribution initially will be the responsibility of NOAA. In any case, the long-term archive and distribution of all Landsat data will be the responsibility of the Department of Interior's U.S. Geological Survey.

Draeger, W.C.; Holm, T.M.; Lauer, D.T.; Thompson, R.J.

1997-01-01

398

LANDSAT-D flight segment operations manual, volume 2  

NASA Technical Reports Server (NTRS)

Functions, performance capabilities, modes of operation, constraints, redundancy, commands, and telemetry are described for the thematic mapper; the global positioning system; the direct access S-band; the multispectral scanner; the payload correction; the thermal control subsystem; the solar array retention, deployment, and jettison assembly; and the boom antenna retention, deployment, and jettison assembly for LANDSAT 4.

Varhola, J.

1981-01-01

399

LANDSAT-4/5 image data quality analysis  

NASA Technical Reports Server (NTRS)

A LANDSAT Thematic Mapper (TM) quality evaluation study was conducted to identify geometric and radiometric sensor errors in the post-launch environment. The study began with the launch of LANDSAT-4. Several error conditions were found, including band-to-band misregistration and detector-to detector radiometric calibration errors. Similar analysis was made for the LANDSAT-5 Thematic Mapper and compared with results for LANDSAT-4. Remaining band-to-band misregistration was found to be within tolerances and detector-to-detector calibration errors were not severe. More coherent noise signals were observed in TM-5 than in TM-4, although the amplitude was generally less. The scan direction differences observed in TM-4 were still evident in TM-5. The largest effect was in Band 4 where nearly a one digital count difference was observed. Resolution estimation was carried out using roads in TM-5 for the primary focal plane bands rather than field edges as in TM-4. Estimates using roads gave better resolution. Thermal IR band calibration studies were conducted and new nonlinear calibration procedures were defined for TM-5. The overall conclusion is that there are no first order errors in TM-5 and any remaining problems are second or third order.

Malaret, E.; Bartolucci, L. A.; Lozano, D. F.; Anuta, P. E.; Mcgillem, C. D.

1984-01-01

400

LANDSAT menhaden and thread herring resources investigation, Gulf of Mexico  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. The most significant achievement thus far includes the successful charting of high probability fishing areas from LANDSAT MSS data and the successful simulation of an operational satellite system to provide tactical information for the commercial harvest of menhaden.

Savastano, K. (principal investigator); Kemmerer, A. J.; Leming, T.; Holley, H.; Faller, K. H.

1977-01-01

401

Forest Type Mapping Using Computer Classification of LANDSAT Data  

Microsoft Academic Search

Computer classification of LANDSAT data from July 24, 1973 has resulted in measurements and maps of forest types for two New Hampshire counties. Signatures were developed from training sites and applied to test areas and then to the counties. Acreages of hardwood and softwood type and total forested area derived through this process compare favorably with Forest Service statistics for

Emily Bryant; Arthur G. Dodge

1976-01-01

402

Simulation of meteorological satellite (METSAT) data using LANDSAT data  

NASA Technical Reports Server (NTRS)

The information content which can be expected from the advanced very high resolution radiometer system, AVHRR, on the NOAA-6 satellite was assessed, and systematic techniques of data interpretation for use with meteorological satellite data were defined. In-house data from LANDSAT 2 and 3 were used to simulate the spatial, spectral, and sampling methods of the NOAA-6 satellite data.

Austin, W. W.; Ryland, W. E.

1983-01-01

403

Absolute calibration of Landsat instruments using the moon.  

USGS Publications Warehouse

A lunar observation by Landsat could provide improved radiometric and geometric calibration of both the Thematic Mapper and the Multispectral Scanner in terms of absolute radiometry, determination of the modulation transfer function, and sensitivity to scattered light. A pitch of the spacecraft would be required. -Authors

Kieffer, H.H.; Wildey, R.L.

1985-01-01

404

On cooperative and efficient overlay network evolution based on a group selection pattern.  

PubMed

In overlay networks, the interplay between network structure and dynamics remains largely unexplored. In this paper, we study dynamic coevolution between individual rational strategies (cooperative or defect) and the overlay network structure, that is, the interaction between peer's local rational behaviors and the emergence of the whole network structure. We propose an evolutionary game theory (EGT)-based overlay topology evolution scheme to drive a given overlay into the small-world structure (high global network efficiency and average clustering coefficient). Our contributions are the following threefold: From the viewpoint of peers' local interactions, we explicitly consider the peer's rational behavior and introduce a link-formation game to characterize the social dilemma of forming links in an overlay network. Furthermore, in the evolutionary link-formation phase, we adopt a simple economic process: Each peer keeps one link to a cooperative neighbor in its neighborhood, which can slightly speed up the convergence of cooperation and increase network efficiency; from the viewpoint of the whole network structure, our simulation results show that the EGT-based scheme can drive an arbitrary overlay network into a fully cooperative and efficient small-world structure. Moreover, we compare our scheme with a search-based economic model of network formation and illustrate that our scheme can achieve the experimental and analytical results in the latter model. In addition, we also graphically illustrate the final overlay network structure; finally, based on the group selection model and evolutionary set theory, we theoretically obtain the approximate threshold of cost and draw the conclusion that the small value of the average degree and the large number of the total peers in an overlay network facilitate the evolution of cooperation. PMID:19726264

Nakao, Akihiro; Wang, Yufeng

2010-04-01

405

On cooperative and efficient overlay network evolution based on a group selection pattern.  

PubMed

In overlay networks, the interplay between network structure and dynamics remains largely unexplored. In this paper, we study dynamic coevolution between individual rational strategies (cooperative or defect) and the overlay network structure, that is, the interaction between peer's local rational behaviors and the emergence of the whole network structure. We propose an evolutionary game theory (EGT)-based overlay topology evolution scheme to drive a given overlay into the small-world structure (high global network efficiency and average clustering coefficient). Our contributions are the following threefold: From the viewpoint of peers' local interactions, we explicitly consider the peer's rational behavior and introduce a link-formation game to characterize the social dilemma of forming links in an overlay network. Furthermore, in the evolutionary link-formation phase, we adopt a simple economic process: Each peer keeps one link to a cooperative neighbor in its neighborhood, which can slightly speed up the convergence of cooperation and increase network efficiency; from the viewpoint of the whole network structure, our simulation results show that the EGT-based scheme can drive an arbitrary overlay network into a fully cooperative and efficient small-world structure. Moreover, we compare our scheme with a search-based economic model of network formation and illustrate that our scheme can achieve the experimental and analytical results in the latter model. In addition, we also graphically illustrate the final overlay network structure; finally, based on the group selection model and evolutionary set theory, we theoretically obtain the approximate threshold of cost and draw the conclusion that the small value of the average degree and the large number of the total peers in an overlay network facilitate the evolution of cooperation. PMID:20199937

Wang, Yufeng; Nakao, Akihiro

2010-06-01

406

Prediction of loss characteristics in built-up areas with various buildings' overlay profiles  

Microsoft Academic Search

We continue the analysis of a probabilistic approach and the corresponding stochastic multi-parametric model of wave propagation in built-up areas with randomly distributed buildings. We concentrate on the influence of buildings' overlay profiles on signal spatial decay, and on path-loss dependence in the frequency domain within UHF\\/X-band urban propagation channels. Using different buildings' overlay profiles, the field-intensity attenuation along radio

N. Blaunstein; D. Katz; D. Censor; A. Freedman; I. Matityahu; I. Gur-Arie

2001-01-01

407

Interactive Guidance by Image Overlay in Robot Assisted Coronary Artery Bypass  

Microsoft Academic Search

\\u000a We present an original visual guidance system in the especially difficult context of robot assisted coronary artery bypass\\u000a graft. The overlay of a preoperative coronary tree model on the endoscopic images is initialized to help the surgeon to locate\\u000a himself. Then the surgeon points some landmarks observed in the operating field during the motion of the endoscope. The overlay\\u000a is

Fabien Mourgues; Thierry Viéville; Volkmar Falk; Ève Coste-manière

2003-01-01

408

Design and fabrication of low-loss hydrogenated amorphous silicon overlay DBR for glass waveguide devices  

Microsoft Academic Search

We report a methodology for the design of low-loss, high-reflectivity, amorphous silicon, overlay DBRs for glass waveguide devices. In order to improve the DBR reflectivity while minimizing the DBR-induced loss, we theoretically determine the optimum overlay thickness and establish an iterative deposition procedure to achieve this value. Details of the design criteria, measurement of the design parameters, and a numerical

Jaeyoun Kim; Kim A. Winick; Catalin Florea; Michael McCoy

2002-01-01

409

Assessment and prediction of drying shrinkage cracking in bonded mortar overlays  

SciTech Connect

Restrained drying shrinkage cracking was investigated on composite beams consisting of substrate concrete and bonded mortar overlays, and compared to the performance of the same mortars when subjected to the ring test. Stress development and cracking in the composite specimens were analytically modeled and predicted based on the measurement of relevant time-dependent material properties such as drying shrinkage, elastic modulus, tensile relaxation and tensile strength. Overlay cracking in the composite beams could be very well predicted with the analytical model. The ring test provided a useful qualitative comparison of the cracking performance of the mortars. The duration of curing was found to only have a minor influence on crack development. This was ascribed to the fact that prolonged curing has a beneficial effect on tensile strength at the onset of stress development, but is in the same time not beneficial to the values of tensile relaxation and elastic modulus. -- Highlights: •Parameter study on material characteristics influencing overlay cracking. •Analytical model gives good quantitative indication of overlay cracking. •Ring test presents good qualitative indication of overlay cracking. •Curing duration has little effect on overlay cracking.

Beushausen, Hans, E-mail: hans.beushausen@uct.ac.za; Chilwesa, Masuzyo

2013-11-15

410

Implementation of Overlay Function Based on Fuzzy Logic in Spatial Decision Support System  

E-print Network

Abstract: The overlay functions in GIS are well known and often needed tools for integrating different factors and generating useful information for decision makers. Both the integration model and the generated information usually rely on crisp set theory. In many cases, either the boundaries of classes are not clearly defined, or the classification of a feature into a class is not obvious. In such cases, overlay based on fuzzy set and fuzzy logic is unavoidable. The aim of this study is to develop overlay functions on the basis of fuzzy logic and to examine the usability of such functions in integrating data related to indeterminate aspects of a phenomenon. To implement and examine the idea, an application program is developed using VBA programming language and the available Arc Object library. Using this application, a user can generate fuzzy data and use different fuzzy overlay functions to integrate those data. To test the applicability of the model and application, the suitable locations for building commercial sites of oil products are determined using this application. In summery, data integration using fuzzy overlay functions can improve the reliability of decisions, when dealing with indeterminate phenomena. Key words: GIS Fuzzy overlay Fuzzy operators Fuzzy membership function

M. S. Mesgari; A. Pirmoradi; G. R. Fallahi

411

Improved CD and overlay metrology using an optical Fourier transform instrument  

NASA Astrophysics Data System (ADS)

We present an innovating method to measure the overlay by scatterometry using an optical Fourier transform (OFT) based system. In order to measure the overlay of patterned layers ? and ?, one line grating is placed in layer ? and another in layer ?. The two gratings have the same pitch and their lines are parallel. The whole scattering pattern of the double grating structure is then measured at fixed wavelength in a large range of incidence (0 to 80°) and for all the azimuth angles. This measurement is very rapid thanks to the OFT and not sensitive to vibration. The main advantage of OFT compared to standard OCD techniques like normal incidence reflectometry or spectroscopic ellipsometry is that the scattering pattern is more sensitive to overlay at an azimuth depending on the pitch value which is never parallel or perpendicular to the grooves of the gratings. In addition, the optical response is also sensitive to the sign of the overlay in addition to its amplitude. In a second method, we propose to measure the overlay simultaneously along the two directions of the plane using two bi-periodic structures patterned in layer ? and ?. By using OFT it is possible to deduce directly from the whole diffracted pattern, the overlay signs and amplitudes along both directions of the plane. The paper presents some simulations and some experimental results to illustrate this new method.

Petit, J.; Boher, P.; Leroux, T.; Barritault, P.; Hazart, J.; Chaton, P.

2005-05-01

412

Analysis of overlay errors induced by exposure energy in negative tone development process for photolithography  

NASA Astrophysics Data System (ADS)

Negative tone development (NTD) process with positive resist and organic solvent-based developer enhances image contrast and uses a light-field mask to make same feature in opposition to positive tone development (PTD). Due to extremely high transmission rate of a light-field mask, absorption of exposure energy on a mask becomes imperceptible. However, the exposure energy transmitted through the mask influences not only lens heating but also wafer heating. Overlay budget by wafer heating becomes a considerable amount in NTD process. In this paper, to clarify overlay change induced by wafer heating in NTD process, four different levels of exposure energy are applied and the overlay errors are deteriorated by increasing energy. Due to wafer heating, the remarkable correlation between Y-overlay errors and scanning direction are observed. Especially, Ty, RK8, and RK12 have mostly considerable correlation with scanning direction. In NTD process, to avoid this phenomenon, exposure energy has to be minimized. In case scanning direction dependency in overlay is not prevented by minimization of exposure energy, fingerprint correction in wafer field is able to reduce this overlay error.

Kim, Young Ha; Kim, Jang-Sun; Kim, Young-Hoon; Cho, Byeong-Ok; Choi, Jinphil; Kang, Young Seog; Ha, Hunhwan

2014-03-01

413

Detecting air pollution stress in southern California vegetation using Landsat Thematic Mapper band data  

NASA Technical Reports Server (NTRS)

Landsat Thematic Mapper (TM) and aircraft-borne Thematic Mapper simulator (TMS) data were collected over two areas of natural vegetation in southern California exposed to gradients of pollutant dose, particularly in photochemical oxidants: the coastal sage scrub of the Santa Monica Mountains in the Los Angeles basin, and the yellow pine forests in the southern Sierra Nevada. In both situations, natural variations in canopy closure, with subsequent exposure of understory elements (e.g.,rock or soil, chaparral, grasses, and herbs), were sufficient to cause changes in spectral variation that could obscure differences due to visible foliar injury symptoms observed in the field. TM or TMS data are therefore more likely to be successful in distinguishing pollution injury from background variation when homogeneous communities with closed canopies are subjected to more severe pollution-induced structural and/or compositional change. The present study helps to define the threshold level of vegetative injury detectable by TM data.

Westman, Walter E.; Price, Curtis V.

1988-01-01

414

Mapping forest succesion types in Siberia with Landsat data  

NASA Astrophysics Data System (ADS)

We develop a forest typology system based on dynamic vegetation approach and apply it to the analysis of the forest type distribution for several test areas in Siberia, aiming at capability of mapping whole Siberian forests based on Landsat data. Test region locations are: two in West Siberian middle taiga (Laryegan and Nyagan), one in Central Siberia and one in East Siberia near Yakutsk. The ground truth data are based on analysis of the field survey, forest inventory data from the point of view of the successional forest type classification. Supervised classification was applied to the areas covered with analysis of the ground truth and inventory data, using several limited area maps and vegetation survey transects published in literature. In Laryegan basin the upland forest areas are dominated (as climax forest species) by Scots pine on sandy soils and Siberian pine with presence of fir and spruce on the others. Those types are separable using Landsat spectral data alone. In the permafrost area around Yakutsk the most widespread succession type is birch to larch succession. Three stages of the birch to larch succession are detectable from Landsat image. When Landsat data is used in both West and East Siberia, distinction between deciduous broad-leaved species (birch, aspen, and willow) is difficult due to similarity in spectral signatures. Same problem exist for distinguishing between dark coniferous species (Siberian pine, fir and spruce). Image classification can be improved by applying landscape type analysis, such as separation into floodplain, terrace, sloping hills. Additional layers of information seem to be a promising way to complement Landsat data, including SAR-based biomass maps and terrain data

Maksyutov, S. S.; Sedykh, V.; Kleptsova, I.; Frolov, A.; Silaev, A.; Kuzmenko, E.; Farber, S.; Kuzmik, N.; Sokolov, V. A.; Fedorov, A.; Nikolaeva, S.

2013-12-01

415

A refined empirical line approach for reflectance factor retrieval from Landsat5 TM and Landsat7 ETM+  

Microsoft Academic Search

The recent launch of Landsat-7 ETM+ extends the uninterrupted stream of TM and ETM+ images to a potential span of 32 years. This exceptional image set will allow long-term studies of natural resources, but will require an operational method for converting image digital number (dn) to the temporally comparable surface reflectance factor (?s?). A refinement to the empirical line (EL)

M. s. Moran; R. Bryant; K. Thome; W. Ni; Y. Nouvellon; M. p. Gonzalez-dugo; J. Qi; T. r. Clarke

2001-01-01

416

Using the overlay assay to qualitatively measure bacterial production of and sensitivity to pneumococcal bacteriocins.  

PubMed

Streptococcus pneumoniae colonizes the highly diverse polymicrobial community of the nasopharynx where it must compete with resident organisms. We have shown that bacterially produced antimicrobial peptides (bacteriocins) dictate the outcome of these competitive interactions. All fully-sequenced pneumococcal strains harbor a bacteriocin-like peptide (blp) locus. The blp locus encodes for a range of diverse bacteriocins and all of the highly conserved components needed for their regulation, processing, and secretion. The diversity of the bacteriocins found in the bacteriocin immunity region (BIR) of the locus is a major contributor of pneumococcal competition. Along with the bacteriocins, immunity genes are found in the BIR and are needed to protect the producer cell from the effects of its own bacteriocin. The overlay assay is a quick method for examining a large number of strains for competitive interactions mediated by bacteriocins. The overlay assay also allows for the characterization of bacteriocin-specific immunity, and detection of secreted quorum sensing peptides. The assay is performed by pre-inoculating an agar plate with a strain to be tested for bacteriocin production followed by application of a soft agar overlay containing a strain to be tested for bacteriocin sensitivity. A zone of clearance surrounding the stab indicates that the overlay strain is sensitive to the bacteriocins produced by the pre-inoculated strain. If no zone of clearance is observed, either the overlay strain is immune to the bacteriocins being produced or the pre-inoculated strain does not produce bacteriocins. To determine if the blp locus is functional in a given strain, the overlay assay can be adapted to evaluate for peptide pheromone secretion by the pre-inoculated strain. In this case, a series of four lacZ-reporter strains with different pheromone specificity are used in the overlay. PMID:25350516

Maricic, Natalie; Dawid, Suzanne

2014-01-01

417

Robotic weld overlay coatings for erosion control. Quarterly technical progress report, July--September, 1994  

SciTech Connect

Research is presently being conducted to develop a criteria for selecting weld overlay coatings for erosion mitigation in Circulated Fluidized Beds. Initially, eleven weld overlay alloys were selected for erosion testing based upon a literature review. All eleven coatings were deposited on 1018 steel substrates using the plasma arc welding process. Ten samples from each coating were prepared for erosion testing. All selected coatings were erosion tested at 400 C and their erosion resistance was evaluated by determining the steady state erosion rate. In addition, the microstructure of each coating was characterized before and after the erosion tests. No correlations were found between room temperature hardness of the weld overlay coatings and their erosion resistance at elevated temperature. It was suggested that weld overlays mechanical properties such as fracture strength, toughness and work hardening rates may contributed to their erosion resistance. During the previous two quarters the microhardness tests were performed on the eroded samples in order to determine the size of the work hardened zone and the change in the coatings hardness due to erosion. As a result of these measurements it was established that one group of coatings deformed plastically, while another did not. In addition, the measurements of the weld overlays microhardness at 400 C were made. The coatings microhardness at 400 C was plotted versus their volume erosion rates. During the last quarter, erosion tests were performed for Inconel-625, 316L SS, and Iron-Aluminide wrought alloys in order to compare their erosion behavior with similar weld overlays. The results of microhardness profile measurements for all weld overlay coatings were analyzed. The factors that contribute to the erosion resistance of the coatings that deformed plastically are discussed in this progress report.

Levin, B.F.; Dupont, J.N.; Marder, A.R.

1994-10-26

418

CliqueStream: An Efficient and Fault-Resilient Live Streaming Network on a Clustered Peer-to-Peer Overlay  

Microsoft Academic Search

Several overlay-based live multimedia streaming plat- forms have been proposed in the recent peer-to-peer stream- ing literature. In most of the cases, the overlay neighbors are chosen randomly for robustness of the overlay. How- ever, this causes nodes that are distant in terms of proximity in the underlying physical network to become neighbors, and thus data travels unnecessary distances before

Shah Asaduzzaman; Ying Qiao; Gregor v. Bochmann

2008-01-01

419

Microstructures and abrasive wear performance of PTAW deposited Ni–WC overlays using different Ni-alloy chemistries  

Microsoft Academic Search

The microstructures and performance of Ni–WC (nickel–tungsten carbide) composite overlays deposited by plasma transferred arc welding are studied using a combination of microscopy, hardness, and wear testing. The Ni–WC overlays had microstructures consisting of ?-Ni dendrites, with interdendritic Ni-based eutectics, borides and carbides. Overlays which were produced with a low hardness Ni-alloy matrix contained a smaller fraction of interdendritic phases

T. Liyanage; G. Fisher; A. P. Gerlich

420

IMPERMEABLE THIN AlâOâ OVERLAY FOR TBC PROTECTION FROM SULFATE AND VANADATE ATTACK IN GAS TURBINES  

Microsoft Academic Search

In order to further improve the hot corrosion resistance of yttria-stabilized zirconia (YSZ), an AlâOâ overlay of 58 μm thick was deposited on the surface of YSZ by electron-beam physical vapor deposition. Hot corrosion tests were performed on the YSZ coatings with γ-AlâOâ overlay and α-AlâOâ overlay in molten salt mixture (Na2SO4 + 5wt%V2O5) at 950 C. The α-AlâOâ overlay

Scott X. Mao

2004-01-01

421

Infrared differential interference contrast microscopy for overlay metrology on 3D-interconnect bonded wafers  

NASA Astrophysics Data System (ADS)

Overlay metrology for stacked layers will be playing a key role in bringing 3D IC devices into manufacturing. However, such bonded wafer pairs present a metrology challenge for optical microscopy tools by the opaque nature of silicon. Using infrared microscopy, silicon wafers become transparent to the near-infrared (NIR) wavelengths of the electromagnetic spectrum, enabling metrology at the interface of bonded wafer pairs. Wafers can be bonded face to face (F2F) or face to back (F2B) which the stacking direction is dictated by how the stacks are carried in the process and functionality required. For example, Memory stacks tend to use F2B stacking enables a better managed design. Current commercial tools use single image technique for F2F bonding overlay measurement because depth of focus is sufficient to include both surfaces; and use multiple image techniques for F2B overlay measurement application for the depth of focus is no longer sufficient to include both stacked wafer surfaces. There is a need to specify the Z coordinate or stacking wafer number through the silicon when visiting measurement wafer sites. Two shown images are of the same (X, Y) but separate Z location acquired at focus position of each wafer surface containing overlay marks. Usually the top surface image is bright and clear; however, the bottom surface image is somewhat darker and noisier as an adhesive layer is used in between to bond the silicon wafers. Thus the top and bottom surface images are further processed to achieve similar brightness and noise level before merged for overlay measurement. This paper presents a special overlay measurement technique, using the infrared differential interference contrast (DIC) microscopy technique to measure the F2B wafer bonding overlay by a single shot image. A pair of thinned wafers at 50 and 150 ?m thickness is bonded on top of a carrier wafer to evaluate the bonding overlay. It works on the principle of interferometry to gain information about the optical path length of the stacked wafers, to enhance the image contrast of overlay marks features even though they are locating in different Z plane. A two dimensional mirror-symmetric overlay marks for both top and bottom processing wafers is designed and printed in each die in order to know and realize the best achievable wafer to wafer bonding processing. A self-developed analysis algorithms is used to identify the overlay error between the stacking wafers and the interconnect structures. The experimental overlay results after wafer bonding including inter-die and intra-die analysis results will be report in the full paper. Correlation of overlay alignment offset data to electrical yield, provides an early indication of bonded wafer yield.

Ku, Yi-sha; Shyu, Deh-Ming; Lin, Yeou-Sung; Cho, Chia-Hung

2013-04-01

422

LANDSAT menhaden and thread herring resources investigation. [Gulf of Mexico  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. The relationship between the distribution of menhaden and selected oceanographic parameters (water color, turbidity, and possibly chlorophyll concentrations) was established. Similar relationships for thread herring were not established nor were relationships relating to the abundance of either species. Use of aircraft and LANDSAT remote sensing instruments to measure or infer a set of basic oceanographic parameters was evaluated. Parameters which could be accurately inferred included surface water temperature, salinity, and color. Water turbidity (Secchi disk) was evaluated as marginally inferrable from the LANDSAT MSS data and chlorophyll-a concentrations as less than marginal. These evaluations considered the parameters only as experienced in the two test areas using available sensors and statistical techniques.

Kemmerer, A. J. (principal investigator); Brucks, J. T.; Butler, J. A.; Faller, K. H.; Holley, H. J.; Leming, T. D.; Savastano, K. J.; Vanselous, T. M.

1977-01-01

423

Spectral characterization of the LANDSAT thematic mapper sensors  

NASA Technical Reports Server (NTRS)

Data collected on the spectral characteristics of the LANDSAT-4 and LANDSAT-4 backup thematic mapper instruments, the protoflight (TM/PF) and flight (TM/F) models, respectively, are presented and analyzed. Tests were conducted on the instruments and their components to determine compliance with two sets of spectral specifications: band-by-band spectral coverage and channel-by-channel within-band spectral matching. Spectral coverage specifications were placed on: (1) band edges--points at 50% of peak response, (2) band edge slopes--steepness of rise and fall-off of response, (3) spectral flatness--evenness of response between edges, and (4) spurious system response--ratio of out-of-band response to in-band response. Compliance with the spectral coverage specifications was determined by analysis of spectral measurements on the individual components contributing to the overall spectral response: filters, detectors, and optical surfaces.

Markham, B. L.; Barker, J. L.

1983-01-01

424

Spatial reasoning to determine stream network from LANDSAT imagery  

NASA Technical Reports Server (NTRS)

In LANDSAT imagery, spectral and spatial information can be used to detect the drainage network as well as the relative elevation model in mountainous terrain. To do this, mixed information of material reflectance in the original LANDSAT imagery must be separated. From the material reflectance information, big visible rivers can be detected. From the topographic modulation information, ridges and valleys can be detected and assigned relative elevations. A complete elevation model can be generated by interpolating values for nonridge and non-valley pixels. The small streams not detectable from material reflectance information can be located in the valleys with flow direction known from the elevation model. Finally, the flow directions of big visible rivers can be inferred by solving a consistent labeling problem based on a set of spatial reasoning constraints.

Haralick, R. M.; Wang, S.; Elliott, D. B.

1983-01-01

425

Landsat analysis for uranium exploration in Northeast Turkey  

USGS Publications Warehouse

No uranium deposits are known in the Trabzon, Turkey region, and consequently, exploration criteria have not been defined. Nonetheless, by analogy with uranium deposits studied elsewhere, exploration guides are suggested to include dense concentrations of linear features, lineaments -- especially with northwest trend, acidic plutonic rocks, and alteration indicated by limonite. A suite of digitally processed images of a single Landsat scene served as the image base for mapping 3,376 linear features. Analysis of the linear feature data yielded two statistically significant trends, which in turn defined two sets of strong lineaments. Color composite images were used to map acidic plutonic rocks and areas of surficial limonitic materials. The Landsat interpretation yielded a map of these exploration guides that may be used to evaluate relative uranium potential. One area in particular shows a high coincidence of favorable indicators.

Lee, Keenan

1983-01-01

426

A Landsat-based inventory procedure for agriculture in California  

NASA Technical Reports Server (NTRS)

Agriculture, which occupies a vital position in the economy of the State of California, depends crucially on the available water. The California Department of Water Resources (DWR) is, therefore, greatly concerned with the total water requirements for agricultural applications. In view of the limitations of an area-limited, single-date survey system, the DWR has been cooperating with NASA and the University of California in a study of the applicability of Landsat imagery and digital data as an aid in making decisions concerning the management of water resources. Attention is given to a statewide inventory of irrigated land, computer-assisted estimation and mapping of irrigated land, and a crop type analysis using Landsat digital data.

Wall, S. L.; Thomas, R. W.; Brown, C. E.; Bauer, E. H.

1982-01-01

427

LANDSAT image studies as applied to petroleum exploration in Kenya  

NASA Technical Reports Server (NTRS)

The Chevron-Kenya oil license, acquired in 1972, covers an area at the north end of the Lamu Embayment. Immediately after acquisition, a photogeologic study of the area was made followed by a short field inspection. An interpretation of LANDSAT-1 images as a separate attempt to improve geological knowledge was completed. The method used in the image study, the multispectral characteristics of rock units and terrain, and the observed anomalous features as seen in the LANDSAT imagery are described. It was found that the study helped to define the relationship of the Lamu Embayment and its internal structure with surrounding regional features, such as the East Africa rifting, the Rudolf Trough, the Bur Acaba structural ridge, and the Ogaden Basin.

Miller, J. B.

1975-01-01

428

Landsat Thematic Mapper geodetic accuracy - Implications for geocoded map compatibility  

NASA Technical Reports Server (NTRS)

The geodetic accuracy and geometric fidelity of corrected thematic mapper (TM) imagery are evaluated. The positional accuracy requirements for the TM are for a single band to within 0.5 pixels of true earth-surface locations at any point over 90 percent of the image and for interband registration to within 0.3 pixel tolerance over 90 percent of the data. Landsat 4 and 5 TM data are analyzed to investigate: (1) single band geometric integrity, (2) 30 m resolution interband registration; (3) image to image conformity; (4) image to ground conformity; and (5) image projective geometry conformity to a mapped earth geometry. The procedures used to study these characteristics are described. The data reveal that Landsat TM digital data met or exceed map accuracy standards for horizontal control.

Bryant, N. A.; Zobrist, A. L.; Walker, R. E.; Gokhmann, B.

1985-01-01

429

Engineering analysis of LANDSAT 1 data for Southeast Asian agriculture  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. LANDSAT spatial resolution was estimated to be adequate, but barely so, for the purpose of detailed assessment of rice or site status. This was due to the spatially fine grain, heterogenous nature of most rice areas. Use of two spectral bands of digital data (MSS 5 and MSS 6 or 7) appeared to be adequate for site recognition and gross site status assessment. Spectral/temporal signatures were found to be more powerful than spectra signatures alone and virtually essential for most analyses of rice growth and rice sites in the Philippine environment. Two band, two date signatures were estimated to be adequate for most purposes, although good results were achieved using one band two- or four-date signatures. A radiometric resolution of 64 levels in each band was found adequate for the analyses of LANDSAT digital data for site recognition and gross site or rice growth assessment.

Mcnair, A. J.; Heydt, H. L.; Liang, T.; Levine, G. (principal investigators)

1976-01-01

430

A comparison of methods for in-chip overlay control at the 65-nm node  

NASA Astrophysics Data System (ADS)

Overlay metrology for production line-monitor and advanced process control (APC) has been dominated by 4-corner box-in-box (BiB) methods for many years. As we proceed following the ITRS roadmap with the development of 65 nm technologies and beyond, it becomes apparent that current overlay methodologies are becoming inadequate for the stringent requirements that lie ahead. It is already apparent that kerf metrology of large scale BiB structures does not correlate well with in-chip design-rule features. The recent introduction of the Advanced Imaging Metrology (AIM) target, utilizing increased information content and advanced design and process compatibility, has demonstrated significant improvements in precision and overlay mark fidelity (OMF) in advanced processes. This paper compares methodologies and strategies for addressing cross-field variation of overlay and pattern placement issues. We compare the trade-offs of run-time intra-field sampling plans and the use of off-line lithography characterization and advanced modeling analysis, and propose new methodologies to address advanced overlay metrology and control.

Robinson, John C.; Stakely, Mark; Poplawski, Jorge M.; Izikson, Pavel; Kassel, Elyakim; Adel, Mike E.

2004-05-01

431

Robotic weld overlay coatings for erosion control. Quarterly technical progress report, January 1994--March 1994  

SciTech Connect

The erosion of materials by the impact of solid particles has received increasing attention during the past twenty years. Recently, research has been initiated with the event of advanced coal conversion processes in which erosion plays an important role. The resulting damage, termed Solid Particle Erosion (SPE), is of concern primarily because of the significantly increased operating costs which result in material failures. Reduced power plant efficiency due to solid particle erosion of boiler tubes and waterwalls has led to various methods to combat SPE. One method is to apply coatings to the components subjected to erosive environments. Protective weld overlay coatings are particularly advantageous in terms of coating quality. The weld overlay coatings are essentially immune to spallation due to a strong metallurgical bond with the substrate material. By using powder mixtures, multiple alloys can be mixed in order to achieve the best performance in an erosive environment. However, a review of the literature revealed a lack of information on weld overlay coating performance in erosive environments which makes the selection of weld overlay alloys a difficult task. The objective of this project is to determine the effects of weld overlay coating composition and microstructure on erosion resistance. These results will lead to a better understanding of erosion mitigation in circulated fluidized beds.

Levin, B.F.; Dupont, J.N.; Marder, A.R.

1994-04-21

432

The Thermal Infrared Sensor on the Landsat Data Continuity Mission  

NASA Technical Reports Server (NTRS)

The Landsat Data Continuity Mission (LDCM), a joint NASA and USGS mission, is scheduled for launch in December, 2012. The LDCM instrument payload will consist of the Operational Land Imager (OLI), provided by Ball Aerospace and Technology Corporation (BATC} under contract to NASA and the Thermal Infrared Sensor (TIRS), provided by NASA's Goddard Space Flight Center (GSFC). This paper outlines the design of the TIRS instrument and gives an example of its application to monitoring water consumption by measuring evapotranspiration.

Reuter, Dennis; Richardson, Cathy; Irons, James; Allen, Rick; Anderson, Martha; Budinoff, Jason; Casto, Gordon; Coltharp, Craig; Finneran, Paul; Forsbacka, Betsy; Hale, Taylor; Jennings, Tom; Jhabvala, Murzy; Lunsford, Allen; Magnuson, Greg; Mills, Rick; Morse, Tony; Otero, Veronica; Rohrbach, Scott; Smith, Ramsey; Sullivan, Terry; Tesfaye, Zelalem; Thome, Kurtis; Unger, Glenn; Whitehouse, Paul

2010-01-01

433

Historical tropical successional forest cover mapped with Landsat MSS imagery  

Microsoft Academic Search

Maps of tropical successional forest cover of the 1970s and 1980s are needed for long-term modelling of tropical forest-cover change, carbon flux and habitat change. Landsat Multispectral Scanner System (MSS) imagery may provide a basis for such maps, but its capability in this respect is poorly unexplored if not discounted. This article examines how reliably single-date MSS imagery may distinguish

Sean Sloan

2012-01-01

434

Research and development of LANDSAT-based crop inventory techniques  

NASA Technical Reports Server (NTRS)

A wide spectrum of technology pertaining to the inventory of crops using LANDSAT without in situ training data is addressed. Methods considered include Bayesian based through-the-season methods, estimation technology based on analytical profile fitting methods, and expert-based computer aided methods. Although the research was conducted using U.S. data, the adaptation of the technology to the Southern Hemisphere, especially Argentina was considered.

Horvath, R.; Cicone, R. C.; Malila, W. A. (principal investigators)

1982-01-01

435

Geological mapping in northwestern Saudi Arabia using LANDSAT multispectral techniques  

NASA Technical Reports Server (NTRS)

Various computer enhancement and data extraction systems using LANDSAT data were assessed and used to complement a continuing geologic mapping program. Interactive digital classification techniques using both the parallel-piped and maximum-likelihood statistical approaches achieve very limited success in areas of highly dissected terrain. Computer enhanced imagery developed by color compositing stretched MSS ratio data was constructed for a test site in northwestern Saudi Arabia. Initial results indicate that several igneous and sedimentary rock types can be discriminated.

Blodget, H. W.; Brown, G. F.; Moik, J. G.

1975-01-01

436

A look at Alaskan resources with Landsat data  

NASA Technical Reports Server (NTRS)

Landsat data remains a vital tool for the management of resources in Alaska. Utilization of these data by many agencies in Alaska trends toward the solution to operational problems in a wide spectrum of disciplinary applications. Four examples of current applications are reviewed briefly: mapping of coastal sediment plumes, mapping of coastal zone ecosystems, mapping of landform and ground cover for proposed national parks and forests, and evaluation of seismic risks for a proposed hydroelectric project.

Miller, J. M.; Belon, A. E.; Gedney, L. D.; Shapiro, L. H.

1975-01-01

437

Relative radiometric calibration of LANDSAT TM reflective bands  

NASA Technical Reports Server (NTRS)

Raw thematic mapper (TM) calibration data from pre-launch tests and in-orbit acquisitions from LANDSAT 4 and 5 satellites are analyzed to assess the radiometric characteristics of the TM sensor. A software program called TM radiometric and algorithmic performance program (TRAPP) was used for the majority of analyses. Radiometric uncertainty in the final TM image originates from: (1) scene variability (solar irradiance and atmospheric scattering); (2) optical and electrical variability of the sensor; and (3) variability introduced during image processing.

Barker, J. L.

1984-01-01

438

An overview of Landsat-4 status and results  

NASA Technical Reports Server (NTRS)

Analyses of Landsat-4 satellite Thematic Mapper (TM) data indicate good spatial, spectral, and radiometric performance. Land cover features such as residential areas and field boundaries, as well as geomorphological features, are more sharply defined with the 30-m nominal resolution of the TM than with the Multispectral Scanner. The new TM spectral bands in the 1.6 and 2.2-micron regions are noted to be useful in the delineation of vegetation types and geological conditions involving hydrothermal alteration.

Salomonson, V. V.; Koffler, R.

1984-01-01

439

Monitoring Interannual Variation in Deciduous Broadleaf Forest Phenology Using Landsat  

NASA Astrophysics Data System (ADS)

Remotely sensed observations of vegetation phenology provide valuable information related to ecosystem responses to climate variability and change. Phenology is also a first-order control on land-atmosphere interactions that affect regional carbon budgets, and remote sensing observations of phenology are often used to parameterize seasonal vegetation dynamics in coupled climate-ecosystems models. Currently available ground and remote sensing-based phenology products possess considerable uncertainty. In particular, a need exists for data sets and methods that link ground-based observations of phenology acquired at local scales, to more widely available moderate resolution remote sensing data sources and products. Further, higher spatial resolution products that resolve finer spatial detail in phenology are needed to better understand local-to-regional dynamics in phenology. Data from the Landsat TM and ETM+ sensors (with a nominal spatial resolution of 30 m) provide an excellent basis for doing this, but have been largely unexplored by the phenology research community. Here we demonstrate that Landsat data has substantial utility for studies of long-term phenology dynamics. We present a technique for characterizing both long-term average and interannual dynamics in the phenology of temperate deciduous broadleaf forests using a multi-decadal time series of Landsat TM/ETM+ images in New England. Assessment of results show that spring and autumn transition dates agree closely with in-situ measurements of phenology collected at the Harvard Forest in central Massachusetts. Application of this method over larger scales has the potential to supply valuable information related to landscape-scale patterns and dynamics in phenology, and also provides useful information related to relationships among in-situ observations of phenology, medium resolution observations from Landsat, and moderate resolution observations from instruments such as MODIS.

Melaas, E. K.; Friedl, M. A.; Zhu, Z.

2012-12-01

440

Characteristics, of TIROS, GOES, DMSP and LANDSAT Systems  

NASA Technical Reports Server (NTRS)

The characteristics of the TIROS, GOES, DMSP and LANDSAT systems of satellites are described. The data listed for each system are altitude of orbit, inclination/position, orbit type, orbits per day, expected operational lifetime and the sensor systems. The sensor systems are described as to wavelength of each channel, resolution, field of view and other pertinent information. Data information such as availability rate, collection method, primary use/application and how to obtain additional information is also given.

Gray, T. I., Jr.; Mccrary, D. G.; Armstrong, T. A. (principal investigators)

1981-01-01