Reusable Metallic Thermal Protection Systems Development

NASA Technical Reports Server (NTRS)

Blosser, Max L.; Martin, Carl J.; Daryabeigi, Kamran; Poteet, Carl C.

1998-01-01

Metallic thermal protection systems (TPS) are being developed to help meet the ambitious goals of future reusable launch vehicles. Recent metallic TPS development efforts at NASA Langley Research Center are described. Foil-gage metallic honeycomb coupons, representative of the outer surface of metallic TPS were subjected to low speed impact, hypervelocity impact, rain erosion, and subsequent arcjet exposure. TPS panels were subjected to thermal vacuum, acoustic, and hot gas flow testing. Results of the coupon and panel tests are presented. Experimental and analytical tools are being developed to characterize and improve internal insulations. Masses of metallic TPS and advanced ceramic tile and blanket TPS concepts are compared for a wide range of parameters.

Impact Testing of Orbiter Thermal Protection System Materials

NASA Technical Reports Server (NTRS)

Kerr, Justin

2006-01-01

This viewgraph presentation reviews the impact testing of the materials used in designing the shuttle orbiter thermal protection system (TPS). Pursuant to the Columbia Accident Investigation Board recommendations a testing program of the TPS system was instituted. This involved using various types of impactors in different sizes shot from various sizes and strengths guns to impact the TPS tiles and the Leading Edge Structural Subsystem (LESS). The observed damage is shown, and the resultant lessons learned are reviewed.

In-flight rain damage tests of the shuttle thermal protection system

NASA Technical Reports Server (NTRS)

Meyer, Robert R., Jr.; Barneburg, Jack

1988-01-01

NASA conducted in-flight rain damage tests of the Shuttle thermal protection system (TPS). Most of the tests were conducted on an F-104 aircraft at the Dryden Flight Research Facility of NASA's Ames Research Center, although some tests were conducted by NOAA on a WP-3D aircraft off the eastern coast of southern Florida. The TPS components tested included LI900 and LI2200 tiles, advanced flexible reusable surface insulation, reinforced carbon-carbon, and an advanced tufi tile. The objective of the test was to define the damage threshold of various thermal protection materials during flight through rain. The test hardware, test technique, and results from both F-104 and WP-3D aircraft are described. Results have shown that damage can occur to the Shuttle TPS during flight in rain.

Conformal Ablative Thermal Protection System for Planetary and Human Exploration Missions:An Overview of the Technology Maturation Effort

NASA Technical Reports Server (NTRS)

Beck, Robin A S.; Arnold, James O.; Gasch, Matthew J.; Stackpoole, Margaret M.; Prabhu, Dinesh K.; Szalai, Christine E.; Wercinski, Paul F.; Venkatapathy, Ethiraj

2013-01-01

The Office of Chief Technologist, NASA identified the need for research and technology development in part from NASAs Strategic Goal 3.3 of the NASA Strategic Plan to develop and demonstrate the critical technologies that will make NASAs exploration, science, and discovery missions more affordable and more capable. Furthermore, the Game Changing Development Program is a primary avenue to achieve the Agencys 2011 strategic goal to Create the innovative new space technologies for our exploration, science, and economic future. The National Research Council (NRC) Space Technology Roadmaps and Priorities report highlights six challenges and they are: Mass to Surface, Surface Access, Precision Landing, Surface Hazard Detection and Avoidance, Safety and Mission Assurance, and Affordability. In order for NASA to meet these challenges, the report recommends immediate focus on Rigid and Flexible Thermal Protection Systems. Rigid TPS systems such as Avcoat or SLA are honeycomb based and PICA is in the form of tiles. The honeycomb systems are manufactured using techniques that require filling of each (38 cell) by hand, and in a limited amount of time all of the cells must be filled and the heatshield must be cured. The tile systems such as PICA pose a different challenge as the low strain-to-failure and manufacturing size limitations require large number of small tiles with gap-fillers between the tiles. Recent investments in flexible ablative systems have given rise to the potential for conformal ablative TPS. A conformal TPS over a rigid aeroshell has the potential to solve a number of challenges faced by traditional rigid TPS materials. The high strain-to-failure nature of the conformal ablative materials will allow integration of the TPS with the underlying aeroshell structure much easier and enable monolithic-like configuration and larger segments (or parts) to be used. By reducing the overall part count, the cost of installation (based on cost comparisons between blanket and tile materials on shuttle) should be significantly reduced. The conformal ablator design will include a simplified design of seams between gore panels, which should eliminate the need for gap filler design, and should accommodate a wider range of allowable carrier structure imperfections when compared to a rigid material such as PICA.The Conformal TPS development project leverages the past investments made by earlier projects with a goal to develop and deliver a TRL 5 conformal TPS capable of 250 Wcm2 for missions such as MSL or COTS missions. The capabilities goal for the conformal TPS is similar to an MSL design reference mission (250 Wcm2) with matching pressures and shear environments. Both conformal and flexible carbon-felt based materials were successfully tested in stagnation aerothermal environments above 500 Wcm2 under earlier programs. Results on a myriad of materials developed during FY11 were used to determine which materials to start with in FY12. In FY12, the conformal TPS element focused on establishing materials requirements based on MSL-type and COTS Low Earth orbit (LEO) conditions (q 250 Wcm2) to develop and deliver a Conformal Ablative TPS. In FY13, development and refining metrics for mission utilization of conformal ablator technology along with assessment for potential mission stakeholders will be carried out.

F-15B in flight with X-33 Thermal Protection Systems (TPS) on Flight Test Fixture

NASA Technical Reports Server (NTRS)

1998-01-01

In-flight photo of the NASA F-15B used in tests of the X-33 Thermal Protection System (TPS) materials. Flying at subsonic speeds, the F-15B tests measured the air loads on the proposed X-33 protective materials. In contrast, shock loads testing investigated the local impact of the supersonic shock wave itself on the TPS materials. Similar tests had been done in 1985 for the space shuttle tiles, using an F-104 aircraft.

F-15B in flight with X-33 Thermal Protection Systems (TPS) on Flight Test Fixture

NASA Image and Video Library

1998-05-14

In-flight photo of the NASA F-15B used in tests of the X-33 Thermal Protection System (TPS) materials. Flying at subsonic speeds, the F-15B tests measured the air loads on the proposed X-33 protective materials. In contrast, shock loads testing investigated the local impact of the supersonic shock wave itself on the TPS materials. Similar tests had been done in 1985 for the space shuttle tiles, using an F-104 aircraft.

Acousto-optic signature analysis for inspection of the orbiter thermal protection tile bonds

NASA Technical Reports Server (NTRS)

Rodriguez, Julio G.; Tow, D. M.; Barna, B. A.

1990-01-01

The goal of this research is to develop a viable NDE technique for the inspection of orbiter thermal protection system (TPS) tile bonds. Phase 2, discussed here, concentrated on developing an empirical understanding of the bonded and unbonded vibration signatures of acreage tiles. Controlled experiments in the laboratory have provided useful information on the dynamic response of TPS tiles. It has been shown that several signatures are common to all the pedigree tiles. This degree of consistency in the tile-SIP (strain isolation pad) dynamic response proves that an unbond can be detected for a known tile and establish the basis for extending the analysis capability to arbitrary tiles for which there are no historical data. The field tests of the noncontacting laser acoustic sensor system, conducted at the Kennedy Space Center (KSC), investigated the vibrational environment of the Orbiter Processing Facility (OPF) and its effect on the measurement and analysis techniques being developed. The data collected showed that for orbiter locations, such as the body flap and elevon, the data analysis scheme, and/or the sensor, will require modification to accommodate the ambient motion. Several methods were identified for accomplishing this, and a solution is seen as readily achievable. It was established that the tile response was similar to that observed in the laboratory. Of most importance, however, is that the field environment will not affect the physics of the dynamic response that is related to bond condition. All of this information is fundamental to any future design and development of a prototype system.

KENNEDY SPACE CENTER, FLA. -- From left, NASA Deputy Associate Administrator for Space Station and Shuttle Programs Michael Kostelnik and United Space Alliance (USA) Vice President and Space Shuttle Program Manager Howard DeCastro are briefed on the properties of the tile used in the Shuttle's Thermal Protection System (TPS) by USA Manager of the TPS Facility Martin Wilson (right). NASA and USA Space Shuttle program management are participating in a leadership workday. The day is intended to provide management with an in-depth, hands-on look at Shuttle processing activities at KSC.

NASA Image and Video Library

2003-12-19

KENNEDY SPACE CENTER, FLA. -- From left, NASA Deputy Associate Administrator for Space Station and Shuttle Programs Michael Kostelnik and United Space Alliance (USA) Vice President and Space Shuttle Program Manager Howard DeCastro are briefed on the properties of the tile used in the Shuttle's Thermal Protection System (TPS) by USA Manager of the TPS Facility Martin Wilson (right). NASA and USA Space Shuttle program management are participating in a leadership workday. The day is intended to provide management with an in-depth, hands-on look at Shuttle processing activities at KSC.

EVA Hazards due to TPS Inspection and Repair

NASA Technical Reports Server (NTRS)

Stewart, Christine E.

2007-01-01

Tile inspection and repair activities have implicit hazards associated with them. When an Extra Vehicular Activities (EVA) crewmember and associated hardware are added into the equation, additional hazards are introduced. Potential hazards to the Extravehicular Mobility Unit (EMU), the Orbiter or the crew member themselves are created. In order to accurately assess the risk of performing a TPS inspection or repair, an accurate evaluation of potential hazards and how adequately these hazards are controlled is essential. The EMU could become damaged due to sharp edges, protrusions, thermal extremes, molten metal or impact with the Orbiter. Tools, tethers and the presence of a crew member in the vicinity of the Orbiter Thermal Protection System (TPS) pose hazards to the Orbiter. Hazards such as additional tile or Reinforced Carbon-Carbon (RCC) damage from a loose tool, safety tethers, crewmember or arm impact are introduced. Additionally, there are hazards to the crew which should be addressed. Crew hazards include laser injury, electrical shock, inability to return to the airlock for EMU failures or Orbiter rapid safing scenarios, as well as the potential inadvertent release of a crew member from the arm/boom. The aforementioned hazards are controlled in various ways. Generally, these controls are addressed operationally versus by design, as the majority of the interfaces are to the Orbiter and the Orbiter design did not originally account for tile repair. The Shuttle Remote Manipulator System (SRMS), for instance, was originally designed to deploy experiments, and therefore has insufficient design controls for retention of the Orbiter Boom Sensor System (OBSS). Although multiple methods to repair the Orbiter TPS exist, the majority of the hazards are applicable no matter which specific repair method is being performed. TPS Inspection performed via EVA also presents some of the same hazards. Therefore, the hazards common to all TPS inspection or repair methods will be addressed.

Shearographic Non-destructive Evaluation of Space Shuttle Thermal Protection Systems

NASA Technical Reports Server (NTRS)

Davis, Christopher K.; Hooker, Jeffery A.; Simmons, Stephen A.; Tenbusch, Kenneth E.

1995-01-01

Preliminary results of shearographic inspections of the shuttle external tank (ET) spray-on foam insulation (SOFI) and solid rocket booster (SRB) Marshall sprayable ablative (MSA-2) epoxy-cork thermal protection systems (TPS) are presented. Debonding SOFI or MSA-2 damage the orbiter 'belly' tile and exposes the ET/SRB to thermal loading. Previous work with the ET/SRB showed promising results with shearography. The first area investigated was the jack pad close-out, one of many areas on the ET where foam is applied at KSC. Voids 0.375 inch were detected in 1.75 inch thick foam using a pressure reduction of less than 0.4 psi. Of primary interest are areas of the ET that directly face the orbiter tile TPS. It is estimated that 90% of tile TPS damage on the orbiter 'belly' results from debonding SOFI during ascent. Test panels modeling these areas were manufactured with programmed debonds to determine the sensitivity of shearography as a function of debond size, SOFI thickness and vacuum. Results show repeatable detection of debonds with a diameter approximately half the SOFI thickness at less than 0.4 psi pressure reduction. Preliminary results are also presented on inspections of MSA-2 and the remote manipulator system (RMS) honeycomb material.

Shearographic non-destructive evaluation of the Space Shuttle

NASA Technical Reports Server (NTRS)

Davis, Christopher K.; Tenbusch, Kenneth E.; Hooker, Jeffery A.; Simmons, Stephen M.

1995-01-01

Preliminary results of shearographic inspections of the shuttle external tank (ET) spray-on foam insulation (SOFI) and solid rocket booster (SRB) Marshall sprayable ablative (MSA-2) epoxy-cork thermal protection systems (TPS) and remote manipulator system (RMS) honeycomb are presented. Debonding SOFI or MSA-2 damage the orbiter belly tile and exposes the ET/SRB to thermal loading. Previous work with the ET/SRB showed promising results with shearography. The first area investigated was the jack pad close-out, one of many areas on the ET where foam is applied at KSC. Voids 0.375 inch were detected in 1.75 inch thick foam using a pressure reduction of less dm 0.4 psi. Of primary interest are areas of the ET that directly face the orbiter tile TPS. It is estimated that 90% of tile TPS damage on the orbiter 'belly' results from debonding SOFI during ascent. Test panels modeling these areas were manufactured with programmed debonds to determine the sensitivity of shearography as a function of debond size, SOFI thickness, and vacuum. Results show a Probability of Detection (POD) of .95 or better for of debonds with a diameter equal to the SOFI thickness at less than 0.4 psi pressure reduction. Preliminary results are also presented on inspections of MSA-2 and the remote manipulator system (RMS) honeycomb material.

Shearographic non-destructive evaluation of space shuttle thermal protection systems

NASA Technical Reports Server (NTRS)

Hooker, Jeffrey A.; Simmons, Stephen M.; Davis, Christopher K.; Tenbusch, Kenneth E.

1995-01-01

Preliminary results of shearographic inspections of the shuttle external tank (ET) spray-on foam insulation (SOFI) and solid rocket booster (SRB) Marshall sprayable ablative (MSA-2) epoxy-cork thermal protection systems (TPS) are presented. Debonding SOFI or MSA-2 damage the orbiter 'belly' tile and exposes the ET/SRB to thermal loading. Previous work with the ET/SRB showed promising results with shearography. The first area investigated was the jack pad close-out, one of many areas on the ET where foam is applied at KSC. Voids 0.375 inch were detected in 1.75 inch thick foam using a pressure reduction of less than 0.4 psi. Of primary interest are areas of the ET that directly face the orbiter tile TPS. It is estimated that 90% of tile TPS damage on the orbiter 'belly' results from debonding SOFI during ascent. Test panels modeling these areas were manufactured with programmed debonds to determine the sensitivity of shearography as a function of debond size, SOFI thickness and vacuum. Results show repeatable detection of debonds with a diameter approximately half the SOFI thickness at less than 0.4 psi pressure reduction. Preliminary results are also presented on inspections of MSA-2 and the remote manipulator system (RMS) honeycomb material

Conformal Ablative Thermal Protection Systems (CA-TPS) for Venus and Saturn Backshells

NASA Technical Reports Server (NTRS)

Beck, R.; Gasch, M.; Stackpoole, M.; Wilder, M.; Boghozian, T.; Chavez-Garcia, J.; Prabhu, Dinesh; Kazemba, Cole D.; Venkatapathy, E.

2016-01-01

This poster provides an overview of the work performed to date on the Conformal Ablative TPS (CA-TPS) element of the TPSM project out of GCDP. Under this element, NASA is developing improved ablative TPS materials based on flexible felt for reinforcement rather than rigid reinforcements. By replacing the reinforcements with felt, the resulting materials have much higher strain-to-failure and are much lower in thermal conductivity than their rigid counterparts. These characteristics should allow for larger tile sizes, direct bonding to aeroshells and even lower weight TPS. The conformal phenolic impregnated carbon felt (C-PICA) is a candidate for backshell TPS for both Venus and Saturn entry vehicles.

Development of an improved coating for polybenzimidazole foam. [for space shuttle heat shields

NASA Technical Reports Server (NTRS)

Neuner, G. J.; Delano, C. B.

1976-01-01

An improved coating system was developed for Polybenzimidazole (PBI) foam to provide coating stability, ruggedness, moisture resistance, and to satisfy optical property requirements (alpha sub (s/epsilon) or = 0.4 and epsilon 0.8) for the space shuttle. The effort was performed in five tasks: Task 1 to establish material and process specifications for the PBI foam, and material specifications for the coatings; Task 2 to identify and evaluate promising coatings; Task 3 to establish mechanical and thermophysical properties of the tile components; Task 4 to determine by systems analysis the potential weight trade-offs associated with a coated PBI TPS; and Task 5 to establish a preliminary quality assurance program. The coated PBI tile was, through screening tests, determined to satisfy the design objectives with a reduced system weight over the baseline shuttle silica LRSI TPS. The developed tile provides a thermally stable, extremely rugged, low thermal conductivity insulator with a well characterized optical coating.

STS-27R OV-104 Orbiter TPS damage review team, volume 1

NASA Technical Reports Server (NTRS)

Thomas, John W. (Compiler)

1989-01-01

Following the return to earth on December 2, 1988, of Orbiter OV-104, Atlantis, it was observed that there was substantial Thermal Protection System (TPS) tile damage present on the lower right fuselage and wing. Damage sites were more numerous than on previous flights and conversely, there was almost no damage present on Atlantis' left side. A review team investigated the cause beginning with a detailed inspection of the Atlantis TPS damage, and a review of related inspection reports to establish an indepth anomaly definition. An exhaustive data review followed. A fault tree and several failure scenarios were developed. Finally, the failure scenarios were categorized as either not possible, possible but not probable, or probable. This and other information gained during the review formed the basis for the team's findings and recommendations. The team concluded that the most probable cause of the severe STS-27R Orbiter tile damage is that the ablative insulating material covering the RH SRB Nose Cap dislodged and struck the Orbiter tile near 85 seconds into flight and possibly that debris from other sources, including repaired insulation and missing joint cork, caused minor tile damage. Findings are presented, and recommendations that are believed pertinent to minimizing the potential for inflight debris are described.

KENNEDY SPACE CENTER, FLA. -- From left, United Space Alliance (USA) Deputy Space Shuttle Program Manager of Operations Loren Shriver, USA Associate Program Manager of Ground Operations Andy Allen, NASA Deputy Associate Administrator for Space Station and Shuttle Programs Michael Kostelnik, and USA Vice President and Space Shuttle Program Manager Howard DeCastro examine a tile used in the Shuttle's Thermal Protection System (TPS) in KSC's TPS Facility. NASA and USA Space Shuttle program management are participating in a leadership workday. The day is intended to provide management with an in-depth, hands-on look at Shuttle processing activities at KSC.

NASA Image and Video Library

2003-12-19

KENNEDY SPACE CENTER, FLA. -- From left, United Space Alliance (USA) Deputy Space Shuttle Program Manager of Operations Loren Shriver, USA Associate Program Manager of Ground Operations Andy Allen, NASA Deputy Associate Administrator for Space Station and Shuttle Programs Michael Kostelnik, and USA Vice President and Space Shuttle Program Manager Howard DeCastro examine a tile used in the Shuttle's Thermal Protection System (TPS) in KSC's TPS Facility. NASA and USA Space Shuttle program management are participating in a leadership workday. The day is intended to provide management with an in-depth, hands-on look at Shuttle processing activities at KSC.

Ceramic-ceramic shell tile thermal protection system and method thereof

NASA Technical Reports Server (NTRS)

Riccitiello, Salvatore R. (Inventor); Smith, Marnell (Inventor); Goldstein, Howard E. (Inventor); Zimmerman, Norman B. (Inventor)

1986-01-01

A ceramic reusable, externally applied composite thermal protection system (TPS) is proposed. The system functions by utilizing a ceramic/ceramic upper shell structure which effectively separates its primary functions as a thermal insulator and as a load carrier to transmit loads to the cold structure. The composite tile system also prevents impact damage to the atmospheric entry vehicle thermal protection system. The composite tile comprises a structurally strong upper ceramic/ceramic shell manufactured from ceramic fibers and ceramic matrix meeting the thermal and structural requirements of a tile used on a re-entry aerospace vehicle. In addition, a lightweight high temperature ceramic lower temperature base tile is used. The upper shell and lower tile are attached by means effective to withstand the extreme temperatures (3000 to 3200F) and stress conditions. The composite tile may include one or more layers of variable density rigid or flexible thermal insulation. The assembly of the overall tile is facilitated by two or more locking mechanisms on opposing sides of the overall tile assembly. The assembly may occur subsequent to the installation of the lower shell tile on the spacecraft structural skin.

KSC-04pd1770

NASA Image and Video Library

2004-09-10

KENNEDY SPACE CENTER, FLA. - Members of a hurricane assessment team from Johnson Space Center and Marshall Space Flight Center tour the Thermal Protection System (TPS) Facility at KSC after Hurricane Frances hit the east coast of Central Florida and Kennedy Space Center. At left is Martin Wilson, manager of the TPS operations. The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof. Equipment and materials that survived the storm have been relocated to the RLV hangar near the KSC Shuttle Landing Facility.

TPS Materials and Costs for Future Reusable Launch Vehicles

NASA Technical Reports Server (NTRS)

Rasky, Dan J.; Milos, Frank S.; Squire, Tom H.; Arnold, James O. (Technical Monitor)

2000-01-01

There is considerable interest in developing new reusable launch vehicles (RLVs) for reducing the cost of transporting payload to and from orbit. This work reviews thirteen candidate thermal protection system (TPS) options currently available for RLVs. It is useful to begin with the current Shuttle TPS layout as a reference. The nose cap and wing leading edge , which reach the highest temperatures, are made of reinforced carbon-carbon (RCC) that is protected from oxidation by an external coating (about 0.020" thick) of silicon-carbide. Most of the windward surface is 9 lb/cubic ft ceramic tiles (LI-900) with a thin (about 0.012") coating of Reaction Cured Glass (RCG). The leeward side of the vehicle is covered largely by AFRSI, a quilted ceramic blanket, and FRSI, a polyamide felt. These four materials can be considered first generation reusable TPS. Since the time of the Shuttle design, considerable progress has been made advancing TPS technologies in terms of thermal performance, robustness, and cost. For each of the major systems, a second generation ceramic TPS has been developed, tested, and characterized. Metallic-based systems have also been developed. For applications requiring RCC in the past, advanced carbon-carbon (ACC) is now available. This material has better mechanical properties, somewhat higher temperature capability to 2900F and greatly increased oxidation resistance. New carbon fiber reinforced silicon-carbide matrix composites (C/SiCs) have shown additional improvement in properties over ACC with use temperatures to 3000F and above. For rigid tiles, NASA Ames has made two significant advancements. The first is a tile substrate called Alumina Enhanced Thermal Barrier, or AETB, that incorporates alumina fibers for improved dimensional stability at high temperatures, to 2600F and above. This material can be made to densities as low as 8 lb/cubic ft. The second is a coating preparation called Toughened Uni-piece Fibrous Insulation, or TUFT, that penetrates about 0.1 in. into the tile substrate. The resulting composite, with a functionally gradient density near the surface, provides orders of magnitude increased damage resistance compared with RCG coated LI-900, with only a small weight increase. The TPS that combines these two developments is called AETB-8/TUFI and has been adopted for high damage areas on the Shuttles. Two notable developments have occur-red in flexible ceramic blanket technology. The first is aluminoborosilicate-based fibers with use temperatures of 2200F and above," in comparison to quartz and silica fiber used in AFRSI which have multi-use temperature limits of 1200 to 1400F. Blankets incorporating these new high temperature fibers are referred to as AFRSI-HT. The second is an integral weaving techniques that produces a fluted core blanket with a smoother surface and greater resistance to aero-acoustic noise, to levels as high as 170 dB. This Ames innovation is called Tailorable Advanced Blanket Insulation, or TABI. Finally, for felt-based TPS, Boeing is developing Polybenzimidazole Blanket Insulation, or PBI, with a multi-use temperature limit of 1000F and above, in contrast to Shuttle FRSI which has a multi-use temperature limit of about 700F. 1.6 NASA Langley and BF Goodrich (formerly Rohr Corp.) have led the development of metallic-based TPS. This activity uses essentially three approaches: metallic tiles which encase a fibrous ceramic batting in a box fabricated largely from metallic honeycombs, typically Nickel based alloys; metallic honeycomb sheets, made of Nickel-based alloys, incorporating a fibrous back-side insulation encapsulated in a metallic foil bag, providing reduced weight; and metallic multi-wall, which is comprised of dimpled Titanium metal sheets, which are stacked and then diffusion bonded at contact points to form the TPS. The Nickel-based systems can be used up to temperatures of about 1800F, and the Titanium system to about 100F. These thirteen TPS materials have pros and cons to their usage in terms of temperature capability, weight, initial cost, and maintenance. Carbon-carbon and C/SiC systems have the highest temperature capability but are relatively expensive and heavy, requiring significant time, expertise, and costly facilities and tools for design and fabrication. Second generation ceramic tiles are relatively light, durable, simple to fabricate and easy to install; however, waterproofing is a concern. Blankets and felts are light, simple, inexpensive, and easy to install over curved vehicle surfaces, but durability and waterproofing are concerns. Metallics are robust and appear to have eliminated waterproofing, but they tend to be heavy and relatively expensive, requiring costly facilities and tools. If thin metal sheets are used to reduce weights, then issues arise from possible metal fatigue and corrosion caused by thermal cycling, pressure oscillations, and environmental exposure. For application to future RLVs, system analyses show that a significant component of the vehicle life cycle cost is from the TPS; however, it is difficult to quantify and to compare the potential savings of advanced systems without performing full vehicle designs using each of the different options. Because this entails a considerable effort and also tends to submerge TPS cost impacts under unrelated vehicle design assumptions, there is a clear need for a simpler quantitative method to evaluate the cost impact of different TPS options. To this end, this work introduces a TPS life-cycle cost parameter which is easily computed and applicable to generic RLVs.

KSC-03pd0323

NASA Image and Video Library

2003-02-07

KENNEDY SPACE CENTER, FLA. -- NASA Administrator Sean O'Keefe (center) greets Brenda Blackmon, a worker in the Thermal Protection System Facility. O'Keefe is visiting the site to learn more about the TPS products and process in protecting orbiters from the intense heat of launch and re-entry. TPS tiles have been discussed in the investigation into the Columbia tragedy that destroyed the orbiter and claimed the lives of seven astronauts.

KSC-03pd0325

NASA Image and Video Library

2003-02-07

KENNEDY SPACE CENTER, FLA. -- NASA Administrator Sean O'Keefe (left) speaks to workers in the Thermal Protection System Facility. O'Keefe is visiting the site to learn more about the TPS products and process in protecting orbiters from the intense heat of launch and re-entry. TPS tiles have been discussed in the investigation into the Columbia tragedy that destroyed the orbiter and claimed the lives of seven astronauts.

KSC-03pd0330

NASA Image and Video Library

2003-02-07

KENNEDY SPACE CENTER, FLA. -- NASA Administrator Sean O'Keefe (third from left) talks to workers in the Thermal Protection System Facility. O'Keefe is visiting the site to learn more about the TPS products and process in protecting orbiters from the intense heat of launch and re-entry. TPS tiles have been discussed in the investigation into the Columbia tragedy that destroyed the orbiter and claimed the lives of seven astronauts.

Thermal protection system repair kit program

NASA Technical Reports Server (NTRS)

1979-01-01

The feasibility and conceptual design aspects of repair materials and procedures for in orbit repair of the space shuttle orbiter TPS tiles are investigated. Material studies to investigate cure in place materials are described including catalyst and cure studies, ablation tests and evaluations, and support mixing and applicator design. The feasibility of the repair procedures, the storage of the TPS, dispensing, and cure problems are addressed.

Method for Molding Planar Billet of Thermally Insulative Material Into Predetermined Non-Planar Shape

NASA Technical Reports Server (NTRS)

Kolodziej, Paul (Inventor); Carroll, Joe A. (Inventor); Smith, Dane (Inventor)

1998-01-01

A method and apparatus is discussed for molding thermal protection system (TPS) tiles for spacecraft. The apparatus and method include a bottom mold member defining a mold surface shaped like a surface of the spacecraft, e.g., the nose cap of wing leading edge, sought to be thermally protected. A flat billet of TPS material is positioned over the periphery of the mold surface, and a hollow weight element that has a periphery configured like the periphery of the mold surface is positioned on the billet. The billet is then heated in accordance with a predetermined heating regime, and during the heating process the weight of the weight element causes the billet to deform to assume the shape of the mold surface. If desired, a TUFI coating is impregnated into the billet prior to heating, and the coating is sintered to the billet during heating. After heating, a composite matrix material, e.g., a graphite or fiberglass cloth which is impregnated with epoxy or polimide, is bonded to the now-shaped tile to support the tile. Silicone can then be impregnated into the now-formed tile to provide flexibility of the tile.

KSC-03pd0324

NASA Image and Video Library

2003-02-07

KENNEDY SPACE CENTER, FLA. -- In the Thermal Protection System Facility, NASA Administrator Sean O'Keefe (left) talks to Martin Wilson, project manager. O'Keefe is visiting the site to learn more about the TPS products and process in protecting orbiters from the intense heat of launch and re-entry. TPS tiles have been discussed in the investigation into the Columbia tragedy that destroyed the orbiter and claimed the lives of seven astronauts.

Assessment of Alternate Thermal Protection Systems for the Space Shuttle Orbiter

NASA Technical Reports Server (NTRS)

Kelly, H. N.; Webb, G. L.

1982-01-01

Candidate concepts are identified. The impact on the Shuttle Orbiter performance life cycle cost, and risk was assessed and technology advances required to bring the selected TPS to operational readiness are defined. The best system is shown to be a hybrid blend of metallic and carbon-carbon TPS concepts. These alternate concepts offer significant improvements in reusability and are mass competitive with the current ceramic tile reusable surface insulation. Programmatic analysis indicates approximately five years are required to bring the concepts to operational readiness.

Thermal Testing of Ablators in the NASA Johnson Space Center Radiant Heat Test Facility

NASA Technical Reports Server (NTRS)

Del Papa, Steven; Milhoan, Jim; Remark, Brian; Suess, Leonard

2016-01-01

A spacecraft's thermal protection system (TPS) is required to survive the harsh environment experienced during reentry. Accurate thermal modeling of the TPS is required to since uncertainties in the thermal response result in higher design margins and an increase in mass. The Radiant Heat Test Facility (RHTF) located at the NASA Johnson Space Center (JSC) replicates the reentry temperatures and pressures on system level full scale TPS test models for the validation of thermal math models. Reusable TPS, i.e. tile or reinforced carbon-carbon (RCC), have been the primary materials tested in the past. However, current capsule designs for MPCV and commercial programs have required the use of an ablator TPS. The RHTF has successfully completed a pathfinder program on avcoat ablator material to demonstrate the feasibility of ablator testing. The test results and corresponding ablation analysis results are presented in this paper.

Thermal mathematical modeling and system simulation of Space Shuttle less subsystem

NASA Technical Reports Server (NTRS)

Chao, D. C.; Battley, H. H.; Gallegos, J. J.; Curry, D. M.

1984-01-01

Applications, validation tests, and upgrades of the two- and three-dimensional system level thermal mathematical system simulation models (TMSSM) used for thermal protection system (TPS) analyses are described. The TMSSM were developed as an aid to predicting the performance requirements and configurations of the Shuttle wing leading edge (WLE) and nose cone (NC) TPS tiles. The WLE and its structure were subjected to acoustic, thermal/vacuum, and air loads tests to simulate launch, on-orbit, and re-entry behavior. STS-1, -2 and -5 flight data led to recalibration of on-board instruments and raised estimates of the thermal shock at the NC and WLE. Baseline heating data are now available for the design of future TPS.

An experimental summary of plasma arc exposures of space shuttle high-temperature reusable surface insulation tile array with a single missing tile (conducted at the Ames Research Center)

NASA Technical Reports Server (NTRS)

Galanter, S. A.

1975-01-01

A space shuttle high temperature reusable surface insulation (HRSI) tile array with a single missing or lost tile was exposed to a hot gas simulated reentry environment to investigate the heating conditions in and around the vicinity of the missing HRSI tile. Heat flux and pressure data for the lost tile condition were obtained by the use of a water cooled lost tile calibration model. The maximum aluminum substrate temperature obtained during the simulated reentry was 128 C (263 F). The lost tile calibration data indicated a maximum heat flux in the lost tile cavity region of 63 percent of the upstream reference value. This test was conducted at the Ames Research Center in the 20 MW semielliptical thermal protection system (TPS) pilot plasma arc test facility.

Fracture behavior of the Space Shuttle thermal protection system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Komine, A.; Kobayashi, A.S.

1983-09-01

Stable crack-growth and fracture-toughness experiments were conducted using precracked specimens machined from LI-900 reusable surface insulation (RSI) tiles of the Space Shuttle thermal protection system (TPS) at room temperature. Similar fracture experiments were conducted on fracture specimens with preexisting cracks at the interface of the tile and the strain isolation pad (SIP). Stable crack growth was not observed in the LI-900 tile fracture specimens which had a fracture toughness of 12.0 kPa sq rt of m. The intermittent subcritical crack growth at the tile-pad interface of the fracture specimens was attributed to successive local pull-outs due to tensile overload inmore » the LI-900 tile and cannot be characterized by linear elastic fracture mechanics. No subcritical interfacial crack growth was observed in the fracture specimens with densified LI-900 tiles where brittle fracture initiated at an interior point away from the densification. 11 references.« less

KSC-03pd0326

NASA Image and Video Library

2003-02-07

KENNEDY SPACE CENTER, FLA. -- In the Thermal Protection System Facility, NASA Administrator Sean O'Keefe looks at a Dome Heat Shield blanket that is used for Shuttle engines. O'Keefe is visiting the site to learn more about the TPS products and process in protecting orbiters from the intense heat of launch and re-entry. TPS tiles have been discussed in the investigation into the Columbia tragedy that destroyed the orbiter and claimed the lives of seven astronauts.

KSC-03pd0332

NASA Image and Video Library

2003-02-07

KENNEDY SPACE CENTER, FLA. -- NASA Administrator Sean O'Keefe (right) visits the Thermal Protection System Facility. At left is Chuck Fontana, associate program manager, Integrated Logistics. O'Keefe is visiting the site to learn more about the TPS products and process in protecting orbiters from the intense heat of launch and re-entry. TPS tiles have been discussed in the investigation into the Columbia tragedy that destroyed the orbiter and claimed the lives of seven astronauts..

Shell-NASA Vibration-Based Damage Characterization

NASA Technical Reports Server (NTRS)

Rollins, John M.

2014-01-01

This article describes collaborative research between Shell International Exploration and Production (IE&P) scientists and ISAG personnel to investigate the feasibility of ultrasonic-based characterization of spacecraft tile damage for in-space inspection applications. The approach was proposed by Shell personnel in a Shell-NASA "speed-matching" session in early 2011 after ISAG personnel described challenges inherent in the inspection of MMOD damage deep within spacecraft thermal protection system (TPS) tiles. The approach leveraged Shell's relevant sensor and analytical expertise. The research addressed the difficulties associated with producing 3D models of MMOD damage cavities under the surface of a TPS tile, given that simple image-based sensing is constrained by line of sight through entry holes that have diameters considerably smaller than the underlying damage cavities. Damage cavity characterization is needed as part of a vehicle inspection and risk reduction capability for long-duration, human-flown space missions. It was hoped that cavity characterization could be accomplished through the use of ultrasonic techniques that allow for signal penetration through solid material.

KSC-04pd1902

NASA Image and Video Library

2004-09-22

KENNEDY SPACE CENTER, FLA. - Workers attempt to secure the roof of the Tile Shop in the Thermal Protection System Facility (TPSF) in preparation for Hurricane Jeanne, which is expected to impact Central Florida Sunday. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, lost approximately 35 percent of its roof during Hurricane Frances, which blew across Central Florida Sept. 4. Jeanne is the fourth hurricane in 45 days to make landfall somewhere in the state.

Orbiter Boom Sensor System and TPS tiles on orbiter Discovery as seen during EVA 3

NASA Image and Video Library

2005-08-03

S114-E-6310 (3 August 2005) --- The Red Sea forms the backdrop for this view featuring a portion of thermal protection tiles on the Space Shuttle Discovery’s underside and the Canadian-built remote manipulator system (RMS) robotic arm while docked to the international space station during the STS-114 mission. The image was photographed by astronaut Stephen K. Robinson (out of frame), mission specialist, during today’s extravehicular activities (EVA).

Microstructural Investigation of High Emittance Glass Coatings on Fibrous Ceramic Insulation

NASA Technical Reports Server (NTRS)

Ellerby, Don; Leiser, Dan; DiFiore, Robert; Figone, Jeff; Smith, Dane; Loehman, Ron; Kotula, Paul

2001-01-01

This viewgraph presentation provides an overview of the Space Shuttle Thermal Protection System (TPS) and the various products incorporated in the TPS. There are three tile systems which include pure silica, fibrous refractory composite insulation (FRCI), and alumina enhanced thermal barrier (AETB). Coating systems include reaction cured glass (RCG) and toughened uni-piece insulation (TUFI). The microstructures of these systems are explored as are the manufacturing processes associated with each. Microstructural investigation using methods such as automated X-ray spectral image analysis (AXSIA) is a crucial part of understanding the mechanical nature of these systems.

FTIR Study of Vapor Offgassing from Orbiter Tile Re-Waterproofing Materials

NASA Technical Reports Server (NTRS)

Mattson, C. B.

1999-01-01

The work presented in this paper was performed to identify and quantify the offgassing behavior of alternative re-waterproofmg materials under investigation for application to Shuttle Orbiter Thermal Protection System (TPS) tile and blanket materials. The purpose was to determine whether the new materials would cause a problem with the operational analysis of residual vapors using the current portable vapor analyzer, a Miran 203. The materials investigated were limited to dimethylethoxysilane (DMES) and proposed solvent selected as suitable for use in re-waterproofing Orbiter TPS. The solvent was selected in another phase of the overall project. Obiter TPS tiles were injected with the re-waterproofing materials under constant conditions of temperature, relative humidity and air flow. The vapor concentrations of offgassing materials were monitored using Fourier Transform Infrared (FTIR) multi-component analysis, and with the Miran 203 instruments. The procedure was to record the time dependent concentrations of offgassing materials as analyzed by the FTIR, and the time response of the Miran 203 to the materials under consideration. The FTIR was calibrated for vapor phase DMES, tetramethyldisiloxane (TMDS), ethanol and the hydrocarbon solvents to be used to dilute the DMES for application to the TPS tile. The Miran 203 was calibrated for the operational measurement of DMES airborne vapors. The FTIR data, shows for the first time that the principal product which offgases from the tile after the first hour is not DMES, but TMDS and ethanol. The Miran 203 response to TMDS is the primary reading after the re-waterproofing operation is completed. The operational use of the Miran 203 to measure DMES vapors after re-waterproofmg operations has been responding to TMDS. The results of this study suggest that the historical complaints that have contributed to the low threshold limit value (TLV) for DMES concentrations, as read with the Miran 203, are actually based on instrumental responses to TMDS, for which no other toxicology information is available at this time. While there is some interference, the use of the tested hydrocarbon solvents does not adversely affect the response of the Miran 203.

Quantification of impact damage in CMC thermal protection systems using thin-film piezoelectric sensors

NASA Astrophysics Data System (ADS)

Kuhr, Samuel J.; Blackshire, James L.

2007-04-01

Thermal protection systems (TPS) are frequently subjected to impacts from micrometeoroids and ground handling during refurbishment. The damage resulting from such impacts can greatly reduce the vehicle's overall ability to resist extreme temperatures. Therefore, it is essential to have a reliable method to detect and quantify the damage resulting from impacts. In this effort, the effectiveness of lightweight thin film piezoelectric sensors was evaluated for impact detection and quantification in CMC wrapped TPS. The sensors, which were adhered to the bottom of the TPS tile, were used to sense impact events occurring on the top of the tile, with the ultimate goal of quantifying the level of impact level and damage state based on the sensed signals. A reasonable correlation between impact load levels and sensed response were observed for load levels between 0.07-1.00 Joules. An increase in signal frequency content was also observed as impact levels were increased, with specific frequency bands occurring in the 2-16 kHz range. A preliminary nondestructive evaluation of the impact damage sites was also accomplished, where a reasonable correlation between the gross damage features (i.e. impact crater dimensions) and signal response was observed.

KSC-04pd1775

NASA Image and Video Library

2004-09-10

KENNEDY SPACE CENTER, FLA. - Members of a hurricane assessment team from Johnson Space Center and Marshall Space Flight Center observe the damage to the roof of the Thermal Protection System (TPS) Facility at KSC after Hurricane Frances hit the east coast of Central Florida and Kennedy Space Center. At left is astronaut Scott Altmann, a member of the team, and at center is Martin Wilson, manager of the TPS operations. The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof. Equipment and materials that survived the storm have been relocated to the RLV hangar near the KSC Shuttle Landing Facility.

KSC-03pd3255

NASA Image and Video Library

2003-12-19

KENNEDY SPACE CENTER, FLA. -- From left, United Space Alliance (USA) Manager of the Thermal Protection System (TPS) Facility Martin Wilson briefs NASA Deputy Associate Administrator for Space Station and Shuttle Programs Michael Kostelnik and USA Vice President and Space Shuttle Program Manager Howard DeCastro on aspects of creating the tile used in the Shuttle's TPS. NASA and USA Space Shuttle program management are participating in a leadership workday. The day is intended to provide management with an in-depth, hands-on look at Shuttle processing activities at KSC.

Foam on Tile Impact Modeling for the Space Shuttle Program

NASA Technical Reports Server (NTRS)

Stellingwerf, R. F.; Robinson, J. H.; Richardson, S.; Evans, S. W.; Stallworth, R.; Hovater, M.

2003-01-01

Following the breakup of the Space Shuttle Columbia during reentry a NASA-wide investigation team was formed to examine the probable damage inflicted on Orbiter Thermal Protection System (TPS) elements by impact of External Tank insulating foam projectiles. Our team was to apply rigorous, physics-based analysis techniques to help determine parameters of interest for an experimental test program, utilize validated codes to investigate the full range of impact scenarios, and use analysis derived models to predict aero-thermal-structural responses to entry conditions. We were to operate on a non-interference basis with the j Team, and were to supply significant findings to that team and to the Orbiter Vehicle Engineering Working Group, being responsive to any solicitations for support from these entities. The authors formed a working sub-group within the larger team to apply the Smooth Particle Hydrodynamics code SPHC to the damage estimation problem. Numerical models of the LI-900 TPS tiles and of the BX-250 foam were constructed and used as inputs into the code. Material properties needed to properly model the tiles and foam were obtained from other working sub-groups who performed tests on these items for this purpose. Two- and three- dimensional models of the tiles were constructed, including the glass outer layer, the densified lower layer of LI-900 insulation, the Nomex felt Strain Isolation Pad (SIP) mounting layer, and the underlying aluminum 2024 vehicle skin. A model for the BX-250 foam including porous compression, elastic rebound, and surface erosion was developed. Code results for the tile damage and foam behavior were extensively validated through comparison with the Southwest Research Institute (SwRI) foam-on-tile impact experiments carried out in 1999. These tests involved small projectiles striking individual tiles and small tile arrays. Following code and model validation we simulated impacts of larger ET foam projectiles on the TPS tile systems used on the wings of the orbiter. Tiles used on the Wing Acreage, the Main Landing Gear Door, and the Carrier Panels near the front edge of the wing were modeled. Foam impacts shot for the CAB investigation were modeled, as well as impacts at larger angles, including rapid rotation of the projectile, and with varying foam properties. General results suggest that foam impacts on tiles at about 500 mph could cause appreciable damage if the impact angle is greater than about 20 degrees. Some variations of the foam properties, such as increased brittleness or increased density could increase damage in some cases. Rapid (17 rps) rotation failed to increase the damage for the two cases considered. This does not rule out other cases in which the rotational energy might lead to an increase in tile damage, but suggests that in most cases rotation will not be an important factor. Similar models will be applied for other impacting materials, other velocities, and other geometries as part of the Return to Flight process.

Shuttle orbiter TPS flight repair kit development

NASA Technical Reports Server (NTRS)

1979-01-01

The design and application of a TPS repair kit is presented. The repair kit is designed for on orbit use by a crew member working in the manned maneuvering unit (MMU). The kit includes the necessary equipment and materials to accomplish the repair tasks which include the following: HRSI emittance coating repair, damaged tile repair, missing tile repair, and multiple tile repair. Two types of repair materials required to do the small area repair and the large area repair are described. The materials area cure in place, silicone base ablator for small damaged areas and precured ablator tile for repair of larger damaged areas is examined. The cure in place ablator is also used as an adhesive to bond the precured tiles in place. An applicator for the cure in place ablator, designed to contain a two-part silicon compound, mix the two components at correct ratio, and dispense the materials at rates compatible with mission timelines established for the EVA is described.

Modeling of ultrasonic and terahertz radiations in defective tiles for condition monitoring of thermal protection systems

NASA Astrophysics Data System (ADS)

Kabiri Rahani, Ehsan

Condition based monitoring of Thermal Protection Systems (TPS) is necessary for safe operations of space shuttles when quick turn-around time is desired. In the current research Terahertz radiation (T-ray) has been used to detect mechanical and heat induced damages in TPS tiles. Voids and cracks inside the foam tile are denoted as mechanical damage while property changes due to long and short term exposures of tiles to high heat are denoted as heat induced damage. Ultrasonic waves cannot detect cracks and voids inside the tile because the tile material (silica foam) has high attenuation for ultrasonic energy. Instead, electromagnetic terahertz radiation can easily penetrate into the foam material and detect the internal voids although this electromagnetic radiation finds it difficult to detect delaminations between the foam tile and the substrate plate. Thus these two technologies are complementary to each other for TPS inspection. Ultrasonic and T-ray field modeling in free and mounted tiles with different types of mechanical and thermal damages has been the focus of this research. Shortcomings and limitations of FEM method in modeling 3D problems especially at high-frequencies has been discussed and a newly developed semi-analytical technique called Distributed Point Source Method (DPSM) has been used for this purpose. A FORTRAN code called DPSM3D has been developed to model both ultrasonic and electromagnetic problems using the conventional DPSM method. This code is designed in a general form capable of modeling a variety of geometries. DPSM has been extended from ultrasonic applications to electromagnetic to model THz Gaussian beams, multilayered dielectrics and Gaussian beam-scatterer interaction problems. Since the conventional DPSM has some drawbacks, to overcome it two modification methods called G-DPSM and ESM have been proposed. The conventional DPSM in the past was only capable of solving time harmonic (frequency domain) problems. Time history was obtained by FFT (Fast Fourier Transform) algorithm. In this research DPSM has been extended to model DPSM transient problems without using FFT. This modified technique has been denoted as t-DPSM. Using DPSM, scattering of focused ultrasonic fields by single and multiple cavities in fluid & solid media is studied. It is investigated when two cavities in close proximity can be distinguished and when it is not possible. A comparison between the radiation forces generated by the ultrasonic energies reflected from two small cavities versus a single big cavity is also carried out.

KSC-04pd1774

NASA Image and Video Library

2004-09-10

KENNEDY SPACE CENTER, FLA. - Members of a hurricane assessment team from Johnson Space Center and Marshall Space Flight Center observe the damage to the roof of the Thermal Protection System (TPS) Facility at KSC after Hurricane Frances hit the east coast of Central Florida and Kennedy Space Center. The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof. Equipment and materials that survived the storm have been relocated to the RLV hangar near the KSC Shuttle Landing Facility.

KENNEDY SPACE CENTER, FLA. -- United Space Alliance (USA) Vice President and Space Shuttle Program Manager Howard DeCastro (left) and NASA Deputy Associate Administrator for Space Station and Shuttle Programs Michael Kostelnik (third from left) watch as a USA technician (right) creates a tile for use in the Shuttle's Thermal Protection System (TPS). NASA and USA Space Shuttle program management are participating in a leadership workday. The day is intended to provide management with an in-depth, hands-on look at Shuttle processing activities at KSC.

NASA Image and Video Library

2003-12-19

KENNEDY SPACE CENTER, FLA. -- United Space Alliance (USA) Vice President and Space Shuttle Program Manager Howard DeCastro (left) and NASA Deputy Associate Administrator for Space Station and Shuttle Programs Michael Kostelnik (third from left) watch as a USA technician (right) creates a tile for use in the Shuttle's Thermal Protection System (TPS). NASA and USA Space Shuttle program management are participating in a leadership workday. The day is intended to provide management with an in-depth, hands-on look at Shuttle processing activities at KSC.

Aerothermal tests of quilted dome models on a flat plate at a Mach number of 6.5

NASA Technical Reports Server (NTRS)

Glass, Christopher E.; Hunt, L. Roane

1988-01-01

Aerothermal tests were conducted in the NASA Langley 8 Foot High Temperature Tunnel (8'HTT) at a Mach number of 6.5 on simulated arrays of thermally bowed metallic thermal protection system (TPS) tiles at an angle of attack of 5 deg. Detailed surface pressures and heating rates were obtained for arrays aligned with the flow and skewed 45 deg diagonally to the flow with nominal bowed heights of 0.1, 0.2, and 0.4 inch submerged in both laminar and turbulent boundary layers. Aerothermal tests were made at a nominal total temperature of 3300 R, a total pressure of 400 psia, a total enthalpy of 950 Btu/lbm, a dynamic pressure of 2.7 psi, and a unit Reynolds number of 400,000 per foot. The experimental results form a data base that can be used to help protect aerothermal load increases from bowed arrays of TPS tiles.

Simulated Reentry Heating by Torching

NASA Technical Reports Server (NTRS)

Harvey, Gale A.

2008-01-01

The two first order reentry heating parameters are peak heating flux (W/cm2) and peak heat load (kJ/cm2). Peak heating flux (and deceleration, gs) is higher for a ballistic reentry and peak heat load is higher for a lifting reentry. Manned vehicle reentries are generally lifting reentries at nominal 1-5 gs so that personnel will not be crushed by high deceleration force. A few off-nominal manned reentries have experienced 8 or more gs with corresponding high heating flux (but below nominal heat load). The Shuttle Orbiter reentries provide about an order of magnitude difference in peak heating flux at mid-bottom (TPS tiles, approximately 6 W/cm2 or 5 BTU/ft2- sec) and leading edge (RCC, approximately 60 W/cm2 or 50 BTU/ft2- sec). Orion lunar return and Mars sample lander are of the same order of magnitude as orbiter leading edge peak heat loads. Flight temperature measurements are available for some orbiter TPS tile and RCC locations. Return-to-Flight on-orbit tile-repair-candidate-material-heating performance was evaluated by matching propane torch heating of candidate-materials temperatures at several depths to orbiter TPS tile flight-temperatures. Char and ash characteristics, heat expansion, and temperature histories at several depths of the cure-in-place ablator were some of the TPS repair material performance characteristics measured. The final char surface was above the initial surface for the primary candidate (silicone based) material, in contrast to a receded surface for the Apollo-type ablative heat shield material. Candidate TPS materials for Orion CEV (LEO and lunar return), and for Mars sample lander are now being evaluated. Torching of a candidate ablator material, PICA, was performed to match the ablation experienced by the STARDUST PICA heat shield. Torching showed that the carbon fiberform skeleton in a sample of PICA was inhomogeneous in that sample, and allowed measurements (of the clumps and voids) of the inhomogeneity. Additional reentry heating-performance characterizations of high temperature insulation materials were performed.

KSC-04pd1839

NASA Image and Video Library

2004-09-18

KENNEDY SPACE CENTER, FLA. - From left, Martin Wilson, manager of Thermal Protection System (TPS) operations for United Space Alliance, briefs NASA Administrator Sean O’Keefe, KSC Director of the Spaceport Services Scott Kerr, NASA Associate Administrator of the Space Operations Mission Directorate William Readdy, and Center Director James Kennedy (right) on the temporary tile shop set up in the RLV hangar. O’Keefe and Readdy are visiting KSC to survey the damage sustained by KSC facilities from Hurricane Frances. The Thermal Protection System Facility (TPSF), which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof in the storm, which blew across Central Florida Sept. 4-5. Undamaged equipment was removed from the TPSF and stored in the hangar. NASA’s three Space Shuttle orbiters -- Discovery, Atlantis and Endeavour - along with the Shuttle launch pads, all of the critical flight hardware for the orbiters and the International Space Station, and NASA’s Swift spacecraft, awaiting launch in October, were well protected and unharmed.

KSC-04pd1773

NASA Image and Video Library

2004-09-10

KENNEDY SPACE CENTER, FLA. - Members of a hurricane assessment team from Johnson Space Center and Marshall Space Flight Center observe the damage to the roof of the Thermal Protection System (TPS) Facility at KSC after Hurricane Frances hit the east coast of Central Florida and Kennedy Space Center. Near the center is astronaut Scott Altmann, a member of the team. The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof. Equipment and materials that survived the storm have been relocated to the RLV hangar near the KSC Shuttle Landing Facility.

Dual Heat Pulse, Dual Layer Thermal Protection System Sizing Analysis and Trade Studies for Human Mars Entry Descent and Landing

NASA Technical Reports Server (NTRS)

McGuire, Mary Kathleen

2011-01-01

NASA has been recently updating design reference missions for the human exploration of Mars and evaluating the technology investments required to do so. The first of these started in January 2007 and developed the Mars Design Reference Architecture 5.0 (DRA5). As part of DRA5, Thermal Protection System (TPS) sizing analysis was performed on a mid L/D rigid aeroshell undergoing a dual heat pulse (aerocapture and atmospheric entry) trajectory. The DRA5 TPS subteam determined that using traditional monolithic ablator systems would be mass expensive. They proposed a new dual-layer TPS concept utilizing an ablator atop a low thermal conductivity insulative substrate to address the issue. Using existing thermal response models for an ablator and insulative tile, preliminary hand analysis of the dual layer concept at a few key heating points indicated that the concept showed potential to reduce TPS masses and warranted further study. In FY09, the followon Entry, Descent and Landing Systems Analysis (EDL-SA) project continued by focusing on Exploration-class cargo or crewed missions requiring 10 to 50 metric tons of landed payload. The TPS subteam advanced the preliminary dual-layer TPS analysis by developing a new process and updated TPS sizing code to rapidly evaluate mass-optimized, full body sizing for a dual layer TPS that is capable of dual heat pulse performance. This paper describes the process and presents the results of the EDL-SA FY09 dual-layer TPS analyses on the rigid mid L/D aeroshell. Additionally, several trade studies were conducted with the sizing code to evaluate the impact of various design factors, assumptions and margins.

Measurement of the complex refractive index and complex dielectric permittivity of T.P.S. Space Shuttle tile materials at millimeter wavelengths

NASA Technical Reports Server (NTRS)

Afsar, Mohammed Nurul; Chi, Hua; Li, Xiaohui

1990-01-01

Complex refractive index and dielectric permittivity studies of presently used Space Shuttle tile materials at millimeter wavelengths reveal these tiles to exhibit similar absorption characteristics to those of fused silica materials. This absorption is mainly related to the water content in the specimen. A strong birefringence is observed at least in one of these fibrous refractory composite materials.

Vacuum/Zero Net-Gravity Application for On-Orbit TPS Tile Repair

NASA Technical Reports Server (NTRS)

Harvey, Gale A.; Humes, Donald H.; Siochi, Emilie J.

2004-01-01

The Orbiter Columbia catastrophically failed during reentry February 1, 2003. All Space Shuttle flights were suspended, including logistics support for the International Space Station. NASA Langley Research Center s (LaRC) Structures and Materials Competency is performing characterizations of candidate materials for on-orbit repair of orbiter Thermal Protection System (TPS) tiles to support Return-to-Flight activities led by Johnson Space Center (JSC). At least ten materials properties or attributes (adhesion to damage site, thermal protection, char/ash strength, thermal expansion, blistering, flaming, mixing ease, application in vacuum and zero gravity, cure time, shelf or storage life, and short-term outgassing and foaming) of candidate materials are of interest for on-orbit repair. This paper reports application in vacuum and zero net-gravity (for viscous flow repair materials). A description of the test apparatus and preliminary results of several candidate materials are presented. The filling of damage cavities is different for some candidate repair materials in combined vacuum and zero net-gravity than in either vacuum or zero net-gravity alone.

Vacuum/Zero Net-Gravity Application for On-Orbit TPS Tile Repair

NASA Technical Reports Server (NTRS)

Harvey, Gale A.; Humes, Donald H.; Siochi, Emilie J.

2004-01-01

The Orbiter Columbia catastrophically failed during reentry February 1, 2003. All space Shuttle flights were suspended, including logistics support for the International Space Station. NASA LaRC s Structures and Materials Competency is performing characterizations of candidate materials for on-orbit repair of orbiter Thermal Protection System (TPS) tiles to support Return-to-Flight activities led by JSC. At least ten materials properties or attributes (adhesion to damage site, thermal protection, char/ash strength, thermal expansion, blistering, flaming, mixing ease, application in vacuum and zero gravity, cure time, shelf or storage life, and short-term outgassing and foaming) of candidate materials are of interest for on-orbit repair. This paper reports application in vacuum and zero net-gravity (for viscous flow repair materials). A description of the test apparatus and preliminary results of several candidate materials are presented. The filling of damage cavities is different for some candidate repair materials in combined vacuum and zero net-gravity than in either vacuum or zero net- gravity alone.

Health Monitoring Technology for Thermal Protection Systems on Reusable Hypersonic Vehicles

NASA Technical Reports Server (NTRS)

Milos, Frank S.; Watters, D. G.; Heinemann, J. M.; Karunaratne, K. S.; Arnold, Jim (Technical Monitor)

2001-01-01

Integrated subsystem health diagnostics is an area where major improvements have been identified for potential implementation into the design of new reusable launch vehicles (RLVs) in order to reduce life cycle costs, to increase safety margins, and to improve mission reliability. This talk summarizes a joint effort between NASA Ames and industry partners to develop rapid non-contact diagnostic tools for health and performance monitoring of thermal protection systems (TPS) on future RLVs. The specific goals for TPS health monitoring are to increase the speed and reliability of TPS inspections for improved operability at lower cost. The technology being developed includes a 3-D laser scanner for examining the exterior surface of the TPS, and a subsurface microsensor suite for monitoring the health and performance of the TPS. The sensor suite consists of passive overlimit sensors and sensors for continuous parameter monitoring in flight. The sensors are integrated with radio-frequency identification (RFID) microchips to enable wireless communication of-the sensor data to an external reader that may be a hand-held scanner or a large portal. Prototypes of the laser system and both types of subsurface sensors have been developed. The laser scanner was tested on Shuttle Orbiter Columbia and was able to dimension surface chips and holes on a variety of TPS materials. The temperature-overlimit microsensor has a diameter under 0.05 inch (suitable for placement in gaps between ceramic TPS tiles) and can withstand 700 F for 15 minutes.

Arcjet Testing of Advanced Conformal Ablative TPS

NASA Technical Reports Server (NTRS)

Gasch, Matthew; Beck, Robin; Agrawal, Parul

2014-01-01

A conformable TPS over a rigid aeroshell has the potential to solve a number of challenges faced by traditional rigid TPS materials (such as tiled Phenolic Impregnated Carbon Ablator (PICA) system on MSL. The compliant (high strain to failure) nature of the conformable ablative materials will allow integration of the TPS with the underlying aeroshell structure much easier and enable monolithic-like configuration and larger segments (or parts) to be used. In May of 2013 the CA250 project executed an arcjet test series in the Ames IHF facility to evaluate a phenolic-based conformal system (named Conformal-PICA) over a range of test conditions from 40-400Wcm2. The test series consisted of four runs in the 13-inch diameter nozzle. Test models were based on SPRITE configuration (a 55-deg sphere cone), as it was able to provide a combination of required heat flux, pressure and shear within a single entry. The preliminary in-depth TC data acquired during that test series allowed a mid-fidelity thermal response model for conformal-PICA to be created while testing of seam models began to address TPS attachment and joining of multiple segments for future fabrication of large-scale aeroshells. Discussed in this paper are the results.

SHEFEX II Flight Instrumentation And Preparation Of Post Flight Analysis

NASA Astrophysics Data System (ADS)

Thiele, Thomas; Siebe, Frank; Gulhan, Ali

2011-05-01

A main disadvantage of modern TPS systems for re- entry vehicles is the expensive manufacturing and maintenance process due to the complex geometry of these blunt nose configurations. To reduce the costs and to improve the aerodynamic performance the German Aerospace Center (DLR) is following a different approach using TPS structures consisting of flat ceramic tiles. To test these new sharp edged TPS structures the SHEFEX I flight experiment was designed and successfully performed by DLR in 2005. To further improve the reliability of the sharp edged TPS design at even higher Mach numbers, a second flight experiment SHEFEX II will be performed in September 2011. In comparison to SHEFEX I the second flight experiment has a fully symmetrical shape and will reach a maximum Mach number of about 11. Furthermore the vehicle has an active steering system using four canards to control the flight attitude during re-entry, e.g. roll angle, angle of attack and sideslip. After a successful flight the evaluation of the flight data will be performed using a combination of numerical and experimental tools. The data will be used for the improvement of the present numerical analysis tools and to get a better understanding of the aerothermal behaviour of sharp TPS structures. This paper presents the flight instrumentation of the SHEFEX II TPS. In addition the concept of the post flight analysis is presented.

GCD TechPort Data Sheets Thermal Protection System Materials (TPSM) Project

NASA Technical Reports Server (NTRS)

Chinnapongse, Ronald L.

2014-01-01

The Thermal Protection System Materials (TPSM) Project consists of three distinct project elements: the 3-Dimensional Multifunctional Ablative Thermal Protection System (3D MAT) project element; the Conformal Ablative Thermal Protection System (CA-TPS) project element; and the Heatshield for Extreme Entry Environment Technology (HEEET) project element. 3D MAT seeks to design, develop and deliver a game changing material solution based on 3-dimensional weaving and resin infusion approach for manufacturing a material that can function as a robust structure as well as a thermal protection system. CA-TPS seeks to develop and deliver a conformal ablative material designed to be efficient and capable of withstanding peak heat flux up to 500 W/ sq cm, peak pressure up to 0.4 atm, and shear up to 500 Pa. HEEET is developing a new ablative TPS that takes advantage of state-of-the-art 3D weaving technologies and traditional manufacturing processes to infuse woven preforms with a resin, machine them to shape, and assemble them as a tiled solution on the entry vehicle substructure or heatshield.

Outgassing products from orbiter TPS materials

NASA Technical Reports Server (NTRS)

Harvey, Gale A.; Lash, Tom J.; Rawls, J. Richard

1995-01-01

The Space Transportation System (STS) orbiters are known to be significant sources of outgassing in low earth orbit (LEO). Infrared and mass spectra of residues and outgassing from orbiter thermal protection tile and an external blanket are presented. Several sources of methyl and phenyl methyl silicones are identified. About fifty pounds of silicones are estimated to be outgassed during an STS mission.

Stand Alone Pressure Measurement Device (SAPMD) for the space shuttle Orbiter, part 1

NASA Technical Reports Server (NTRS)

Tomlinson, Bill

1989-01-01

The specifications for the Stand Alone Pressure Measurement Device (SAPMD) are as follows: the SAPMD shall measure ambient pressure at the surface of the Orbiter TPS in the range of 0 to 15 pounds per square inch absolute (PSIA). Measurement will begin at solid rocket booster (SRB) ignition as sensed by appropriate vibration sensing elements in the SAPMD. Pressure and corresponding real-time data are to be recorded every one tenth second for 140 seconds and at the end of the recording period, the operation will be discontinued with the data preserved for interrogation subsequent to Orbiter re-entry and landing. The type and size of the battery shall be such as to allow the vibration sensing elements and a real-time clock to be initialized a minimum of 30 day prior to launch and still provide power as necessary to perform the 140 second data recording period after SRB ignition. Battery installation shall be in such a manner as to allow battery replacement without removing the SAPMD from its position or removing more than one TPS tile. The SAPMD must be mounted in specific locations under tile of the TPS. To accommodate such mounting, the absolute maximum physical dimensions much not exceed 6.0 inches in length, 1.5 inches in width, and 0.4 inches in height, and the device shall be of such configuration that it can be bonded to the Orbiter skin at the joint line of two TPS tiles with the pressure sensing port at the surface of the tile. The SAPMD must remain operational in the temperature range of -40 to +85 C and survive storage temperature of -55 to +125 C. The pressure port must withstand 934 C without causing damage to the TPS during entry and must remain functional at 262 C during ascent. The accuracy of the pressure measurement must be plus or minus one-half PSIA over a temperature range of 0 to +36 C. All the specifications were met and verified by prototype testing and documented in the enclosed test data. Four flight-qualified models were fabricated and of these, two were delivered and successfully flown in the cargo bay of STS-26.

Users guide: Steady-state aerodynamic-loads program for shuttle TPS tiles

NASA Technical Reports Server (NTRS)

Kerr, P. A.; Petley, D. H.

1984-01-01

A user's guide for the computer program that calculates the steady-state aerodynamic loads on the Shuttle thermal-protection tiles is presented. The main element in the program is the MITAS-II, Martin Marietta Interactive Thermal Analysis System. The MITAS-II is used to calculate the mass flow in a nine-tile model designed to simulate conditions duing a Shuttle flight. The procedures used to execute the program using the MITAS-II software are described. A list of the necessry software and data files along with a brief description of their functions is given. The format of the data file containing the surface pressure data is specified. The interpolation techniques used to calculate the pressure profile over the tile matrix are briefly described. In addition, the output from a sample run is explained. The actual output and the procedure file used to execute the program at NASA Langley Research Center on a CDC CYBER-175 are provided in the appendices.

Conformal Ablative Thermal Protection System for Planetary and Human Exploration Missions

NASA Technical Reports Server (NTRS)

Beck, R.; Arnold, J.; Gasch, M.; Stackpole, M.; Wercinski, R.; Venkatapathy, E.; Fan, W.; Thornton, J; Szalai, C.

2012-01-01

The Office of Chief Technologist (OCT), NASA has identified the need for research and technology development in part from NASAs Strategic Goal 3.3 of the NASA Strategic Plan to develop and demonstrate the critical technologies that will make NASAs exploration, science, and discovery missions more affordable and more capable. Furthermore, the Game Changing Development Program (GCDP) is a primary avenue to achieve the Agencys 2011 strategic goal to Create the innovative new space technologies for our exploration, science, and economic future. In addition, recently released NASA Space Technology Roadmaps and Priorities, by the National Research Council (NRC) of the National Academy of Sciences stresses the need for NASA to invest in the very near term in specific EDL technologies. The report points out the following challenges (Page 2-38 of the pre-publication copy released on February 1, 2012): Mass to Surface: Develop the ability to deliver more payload to the destination. NASA's future missions will require ever-greater mass delivery capability in order to place scientifically significant instrument packages on distant bodies of interest, to facilitate sample returns from bodies of interest, and to enable human exploration of planets such as Mars. As the maximum mass that can be delivered to an entry interface is fixed for a given launch system and trajectory design, the mass delivered to the surface will require reductions in spacecraft structural mass more efficient, lighter thermal protection systems more efficient lighter propulsion systems and lighter, more efficient deceleration systems. Surface Access: Increase the ability to land at a variety of planetary locales and at a variety of times. Access to specific sites can be achieved via landing at a specific location(s) or transit from a single designated landing location, but it is currently infeasible to transit long distances and through extremely rugged terrain, requiring landing close to the site of interest. The entry environment is not always guaranteed with a direct entry, and improving the entry systems robustness to a variety of environmental conditions could aid in reaching more varied landing sites. The National Research Council (NRC) Space Technology Roadmaps and Priorities report highlights six challenges and they are: 1) Mass to Surface, 2) Surface Access, 3) Precision Landing, 4) Surface Hazard Detection and Avoidance, 5) Safety and Mission Assurance, and 6) Affordability. In order for NASA to meet these challenges, the report recommends immediate focus on Rigid and Flexible Thermal Protection Systems. Rigid TPS systems such as Avcoat or SLA are honeycomb based and PICA is in the form of tiles. The honeycomb systems is manufactured using techniques that require filling of each (3/8 cell) by hand and within a limited amount of time once the ablative compound is mixed, all of the cells have to be filled and the entire heat-shield has to be cured. The tile systems such as PICA pose a different challenge as the mechanical strength characteristic and the manufacturing limitations require large number of small tiles with gap-fillers between the tiles. Recent investments in flexible ablative systems have given rise to the potential for conformal ablative TPS> A conformal TPS over a rigid aeroshell has the potential to solve a number of challenges faced by traditional rigid TPS materials.

Results of Two-Stage Light-Gas Gun Development Efforts and Hypervelocity Impact Tests of Advanced Thermal Protection Materials

NASA Technical Reports Server (NTRS)

Cornelison, C. J.; Watts, Eric T.

1998-01-01

Gun development efforts to increase the launching capabilities of the NASA Ames 0.5-inch two-stage light-gas gun have been investigated. A gun performance simulation code was used to guide initial parametric variations and hardware modifications, in order to increase the projectile impact velocity capability to 8 km/s, while maintaining acceptable levels of gun barrel erosion and gun component stresses. Concurrent with this facility development effort, a hypervelocity impact testing series in support of the X-33/RLV program was performed in collaboration with Rockwell International. Specifically, advanced thermal protection system materials were impacted with aluminum spheres to simulate impacts with on-orbit space debris. Materials tested included AETB-8, AETB-12, AETB-20, and SIRCA-25 tiles, tailorable advanced blanket insulation (TABI), and high temperature AFRSI (HTA). The ballistic limit for several Thermal Protection System (TPS) configurations was investigated to determine particle sizes which cause threshold TPS/structure penetration. Crater depth in tiles was measured as a function of impact particle size. The relationship between coating type and crater morphology was also explored. Data obtained during this test series was used to perform a preliminary analysis of the risks to a typical orbital vehicle from the meteoroid and space debris environment.

Shuttle Upgrade Program: Tile TPS

NASA Technical Reports Server (NTRS)

Leiser, Daniel B.; Stewart, David A.; DiFiore, Robert; Irby, Ed; Arnold, James (Technical Monitor)

2001-01-01

One of the areas where the thermal protection system on the Space Shuttle Orbiter could be improved is the RSI (Reusable Surface Insulation) tile. The improvement would be in damage resistance that would reduce the resultant maintenance and inspection required. It has performed very well in every other aspect. Improving the system's damage resistance has been the subject of much research over the past several years. One of the results of that research was a new system developed for damage prone areas on the orbiter (i.e., base heat shield). That system, designated as TUFI, Toughened Uni-Piece Fibrous Insulation, was successfully demonstrated as an experiment on the Orbiter and is now baselined for the base heat shield. This paper describes the results of a current research program to further improve the TUFI tile system, thus making it applicable to more areas on the orbiter. The way to remove the current limitations of the TUFI system (i.e., weight or thermal conductivity differences between it and the baseline tile (LI-900)) is to improve the characteristics of LI-900 or AETB-8. Specifically this paper describes the results of two efforts. The first shows performance data of an improved LI-900 system involving the application of TUFI and the second describes data that shows a reduced difference in thermal conductivity between the advanced TUFI substrate (AETB-8) now used on the orbiter and LI-900.

Ceramic Foams for TPS Applications

NASA Technical Reports Server (NTRS)

Stockpoole, Mairead

2003-01-01

Ceramic foams have potential in many areas of Thermal Protection Systems (TPS) including acreage and tile leading edges as well as being suitable as a repair approach for re-entry vehicles. NASA Ames is conducting ongoing research in developing lower-density foams from pre-ceramic polymer routes. One of the key factors to investigate, when developing new materials for re-entry applications, is their oxidation behavior in the appropriate re-entry environment which can be simulated using ground based arc jet (plasma jet) testing. Arc jet testing is required to provide the appropriate conditions (stagnation pressures, heat fluxes, enthalpies, heat loads and atmospheres) encountered during flight. This work looks at the response of ceramic foams (Si systems) exposed to simulated reentry environments and investigates the influence of microstructure and composition on the material? response. Other foam properties (mechanical and thermal) will also be presented.

Lightweight Ablative and Ceramic Thermal Protection System Materials for NASA Exploration Systems Vehicles

NASA Technical Reports Server (NTRS)

Valentine, Peter G.; Lawrence, Timothy W.; Gubert, Michael K.; Milos, Frank S.; Kiser, James D.; Ohlhorst, Craig W.; Koenig, John R.

2006-01-01

As a collaborative effort among NASA Centers, the "Lightweight Nonmetallic Thermal Protection Materials Technology" Project was set up to assist mission/vehicle design trade studies, to support risk reduction in thermal protection system (TPS) material selections, to facilitate vehicle mass optimization, and to aid development of human-rated TPS qualification and certification plans. Missions performing aerocapture, aerobraking, or direct aeroentry rely on advanced heatshields that allow reductions in spacecraft mass by minimizing propellant requirements. Information will be presented on candidate materials for such reentry approaches and on screening tests conducted (material property and space environmental effects tests) to evaluate viable candidates. Seventeen materials, in three classes (ablatives, tiles, and ceramic matrix composites), were studied. In additional to physical, mechanical, and thermal property tests, high heat flux laser tests and simulated-reentry oxidation tests were performed. Space environmental effects testing, which included exposures to electrons, atomic oxygen, and hypervelocity impacts, was also conducted.

KSC-04pd1841

NASA Image and Video Library

2004-09-18

KENNEDY SPACE CENTER, FLA. - Martin Wilson (second from right), manager of Thermal Protection System (TPS) operations for United Space Alliance (USA), briefs NASA Administrator Sean O’Keefe, KSC Director of Shuttle Processing Michael E. Wetmore and Center Director James Kennedy about the temporary tile shop set up in the RLV hangar. At far right is USA Manager of Soft Goods Production in the TPSF, Kevin Harrington. O’Keefe and NASA Associate Administrator of Space Operations Mission Directorate William Readdy are visiting KSC to survey the damage sustained by KSC facilities from Hurricane Frances. The Thermal Protection System Facility (TPSF), which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof in the storm, which blew across Central Florida Sept. 4-5. Undamaged equipment was removed from the TPSF and stored in the hangar. The Labor Day storm also caused significant damage to the Vehicle Assembly Building and Processing Control Center. Additionally, the Operations and Checkout Building, Vertical Processing Facility, Hangar AE, Hangar S and Hangar AF Small Parts Facility each received substantial damage. However, well-protected and unharmed were NASA’s three Space Shuttle orbiters -- Discovery, Atlantis and Endeavour - along with the Shuttle launch pads, all of the critical flight hardware for the orbiters and the International Space Station, and NASA’s Swift spacecraft that is awaiting launch in October.

Replacement of Ablators with Phase-Change Material for Thermal Protection of STS Elements

NASA Technical Reports Server (NTRS)

Kaul, Raj K.; Stuckey, Irvin; Munafo, Paul M. (Technical Monitor)

2002-01-01

As part of the research and development program to develop new Thermal Protection System (TPS) materials for aerospace applications at NASA's Marshall Space Flight Center (MSFC), an experimental study was conducted on a new concept for a non-ablative TPS material. Potential loss of TPS material and ablation by-products from the External Tank (ET) or Solid Rocket Booster (SRB) during Shuttle flight with the related Orbiter tile damage necessitates development of a non-ablative thermal protection system. The new Thermal Management Coating (TMC) consists of phase-change material encapsulated in micro spheres and a two-part resin system to adhere the coating to the structure material. The TMC uses a phase-change material to dissipate the heat produced during supersonic flight rather than an ablative material. This new material absorbs energy as it goes through a phase change during the heating portion of the flight profile and then the energy is slowly released as the phase-change material cools and returns to its solid state inside the micro spheres. The coating was subjected to different test conditions simulating design flight environments at the NASA/MSFC Improved Hot Gas Facility (IHGF) to study its performance.

Fiber Optic High Temperature Sensors for Re-Entry Vehicles

NASA Astrophysics Data System (ADS)

Haddad, E.; Kruzelecky, R.; Zou, J.; Wong, B.; Jamroz, W.; Sayeed, F.; Muylaert, J.-M.; McKenzie, I.

2009-01-01

MPB, within an ESA contract, is developing high temperature Fiber sensors (up to 1100°C) for re- ntry experiments, with direct application to the Thermo Protection Surface (TPS) of SHEFEX II. It addresses the challenges of obtaining high reflectivity FBG sensors, and integrating the fiber sensors within the selected TPS host material (C/SiC). Feasibility was demonstrated using free fiber sensors that showed the formation of the Chemical Composition Grating (CCG), with 80 % reflection at temperatures >750°C. The CCG grating was stable at high temperature (1000°C) for more than 50 hours, as well as after cycling between room temperature and 1000°C, with better than 0.5 % temperature accuracy (FBG central wavelength). Small FBG sensor packages were prepared and attached to C/SiC tiles. The calibration of the packaged fibers showed similar response to temperature as the free fiber sensor. The fiber sensor package was designed to maximize contact with the C/SiC surface to provide fast response to transients. Three- imension modeling with Ansys finite element analysis shows a time constant of 15-20 ms to reach 1200°C. A modular design will be implemented where a dedicated fiber line with 3 sensors and its own connector is used for each C/SiC tile. Small coupons of packaged sensors attached to C/SiC tiles will be tested in a re-entry environment at Von Karman Institute (Belgium) In a recently completed project with ESA, MPB developed and ground qualified a fiber sensor network, the "Fiber Sensor Demonstrator", that was successfully integrated as a payload with ESA's Proba-2. The system includes a central interrogation system that can be used to measure multiple parameters including a high temperature sensor for the Proba-2 thruster (up to 500°C).

KSC-04PD-1794

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. United Space Alliance worker Kathy Evans works on equipment in the temporary tile shop set up in the RLV hangar at KSC. The hurricane-ravaged Thermal Protection System Facility (TPSF), which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. Undamaged equipment was removed from the TPSF and stored in the hangar. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1793

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - United Space Alliance worker Janet Mills works on equipment in the temporary tile shop set up in the RLV hangar at KSC. The hurricane-ravaged Thermal Protection System Facility (TPSF), which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. Undamaged equipment was removed from the TPSF and stored in the hangar. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1789

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - A temporary tile shop has been set up in the RLV hangar at KSC after equipment was removed from the hurricane-ravaged Thermal Protection System Facility (TPSF). Here United Space Alliance worker Bab Jarosz works with the 30-needle sewing machines. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1794

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - United Space Alliance worker Kathy Evans works on equipment in the temporary tile shop set up in the RLV hangar at KSC. The hurricane-ravaged Thermal Protection System Facility (TPSF), which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. Undamaged equipment was removed from the TPSF and stored in the hangar. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

Detection of impact damage on thermal protection systems using thin-film piezoelectric sensors for integrated structural health monitoring

NASA Astrophysics Data System (ADS)

Na, Jeong K.; Kuhr, Samuel J.; Jata, Kumar V.

2008-03-01

Thermal Protection Systems (TPS) can be subjected to impact damage during flight and/or during ground maintenance and/or repair. AFRL/RXLP is developing a reliable and robust on-board sensing/monitoring capability for next generation thermal protection systems to detect and assess impact damage. This study was focused on two classes of metallic thermal protection tiles to determine threshold for impact damage and develop sensing capability of the impacts. Sensors made of PVDF piezoelectric film were employed and tested to evaluate the detectability of impact signals and assess the onset or threshold of impact damage. Testing was performed over a range of impact energy levels, where the sensors were adhered to the back of the specimens. The PVDF signal levels were analyzed and compared to assess damage, where digital microscopy, visual inspection, and white light interferometry were used for damage verification. Based on the impact test results, an assessment of the impact damage thresholds for each type of metallic TPS system was made.

KSC-04pd1840

NASA Image and Video Library

2004-09-18

KENNEDY SPACE CENTER, FLA. - Martin Wilson (second from right), manager of Thermal Protection System (TPS) operations for United Space Alliance (USA) , introduces Kevin Harrington, manager of Soft Goods Production in the TPSF, during a briefing to (from left) NASA Administrator Sean O’Keefe, KSC Director of Shuttle Processing Michael E. Wetmore, Center Director James Kennedy and KSC Director of the Spaceport Services Scott Kerr (behind Kennedy), on the temporary tile shop set up in the RLV hangar. O’Keefe and NASA Associate Administrator of Space Operations Mission Directorate William Readdy are visiting KSC to survey the damage sustained by KSC facilities from Hurricane Frances. The Thermal Protection System Facility (TPSF), which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof in the storm, which blew across Central Florida Sept. 4-5. The Labor Day storm also caused significant damage to the Vehicle Assembly Building and Processing Control Center. Additionally, the Operations and Checkout Building, Vertical Processing Facility, Hangar AE, Hangar S and Hangar AF Small Parts Facility each received substantial damage. Undamaged equipment was removed from the TPSF and stored in the hangar. However, well-protected and unharmed were NASA’s three Space Shuttle orbiters -- Discovery, Atlantis and Endeavour - along with the Shuttle launch pads, all of the critical flight hardware for the orbiters and the International Space Station, and NASA’s Swift spacecraft that is awaiting launch in October.

KSC-04pd1791

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - United Space Alliance worker Bab Jarosz works with the 30-needle sewing machines from the Thermal Protection System Facility (TPSF). A temporary tile shop has been set up in the RLV hangar at KSC after equipment was removed from the hurricane-ravaged facility. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1790

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - United Space Alliance worker Bab Jarosz works with the 30-needle sewing machines from the Thermal Protection System Facility (TPSF). A temporary tile shop has been set up in the RLV hangar at KSC after equipment was removed from the hurricane-ravaged facility. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

Evaluation of Thermal Protection Tile Transmissibility for Ground Vibration Test

NASA Technical Reports Server (NTRS)

Chung, Y. T.; Fowler, Samuel B.; Lo, Wenso; Towner, Robert

2005-01-01

Transmissibility analyses and tests were conducted on a composite panel with thermal protection system foams to evaluate the quality of the measured frequency response functions. Both the analysis and the test results indicate that the vehicle dynamic responses are fully transmitted to the accelerometers mounted on the thermal protection system in the normal direction below a certain frequency. In addition, the in-plane motions of the accelerometer mounted on the top surface of the thermal protection system behave more actively than those on the composite panel due to the geometric offset of the accelerometer from the panel in the test set-up. The transmissibility tests and analyses show that the frequency response functions measured from the accelerometers mounted on the TPS will provide accurate vehicle responses below 120 Hz for frequency and mode shape identification. By confirming that accurate dynamic responses below a given frequency can be obtained, this study increases the confidence needed for conducting the modal testing, model correlation, and model updating for a vehicle installed with TPS. '

Multiwall TPS: An emerging concept

NASA Technical Reports Server (NTRS)

Shideler, J. L.; Kelly, H. N.; Avery, D. E.; Blosser, M. L.; Adelman, H. M.

1981-01-01

The transformation of a titanium multiwall thermal protection system from a conceptual design to a working reality is described. The thermal and structural performance of the basic multiwall concept is analyzed. Radiant heat, wind tunnel, vibration, acoustic, and lightning strike tests are used to verify the performance of multiwall tiles under representative operating conditions. Flat, all titanium multiwall configurations limited to temperature below 810 K are discussed. Curved surface, higher temperature versions of the multiwall are considered. Preliminary mass estimates for advanced multiwall concepts are presented.

In-flight investigation of shuttle tile pressure orifice installations

NASA Technical Reports Server (NTRS)

Moes, Timothy R.; Meyer, Robert R., Jr.

1990-01-01

To determine shuttle orbiter wing loads during ascent, wing load instrumentation was added to Columbia (OV-102). This instrumentation included strain gages and pressure orifices on the wing. The loads derived from wing pressure measurements taken during STS 61-C did not agree with those derived from strain gage measurements or with the loads predicted from the aerodynamic database. Anomalies in the surface immediately surrounding the pressure orifices in the thermal protection system (TPS) tiles were one possible cause of errors in the loads derived from wing pressure measurements. These surface anomalies were caused by a ceramic filler material which was installed around the pressure tubing. The filler material allowed slight movement of the TPS tile and pressure tube as the airframe flexed and bent under aerodynamic loads during ascent and descent. Postflight inspection revealed that this filler material had protruded from or receeded beneath the surface, causing the orifice to lose its flushness. Flight tests were conducted at NASA Ames Research Center Dryden Flight Research Facility to determine the effects of any anomaly in surface flushness of the orifice installation on the measured pressures at Mach numbers between 0.6 and 1.4. An F-104 aircraft with a flight test fixture mounted beneath the fuselage was used for these flights. Surface flushness anomalies typical of those on the orbiter after flight (STA 61-C) were tested. Also, cases with excessive protrusion and recession of the filler material were tested. This report shows that the anomalies in STS 61-C orifice installations adversely affected the pressure measurements. But the magnitude of the affect was not great enough to account for the discrepancies with the strain gage measurements and the aerodynamic predictions.

BLIMPK/Streamline Surface Catalytic Heating Predictions on the Space Shuttle Orbiter

NASA Technical Reports Server (NTRS)

Marichalar, Jeremiah J.; Rochelle, William C.; Kirk, Benjamin S.; Campbell, Charles H.

2006-01-01

This paper describes the results of an analysis of localized catalytic heating effects to the U.S. Space Shuttle Orbiter Thermal Protection System (TPS). The analysis applies to the High-temperature Reusable Surface Insulation (HRSI) on the lower fuselage and wing acreage, as well as the critical Reinforced Carbon-Carbon on the nose cap, chin panel and the wing leading edge. The object of the analysis was to use a modified two-layer approach to predict the catalytic heating effects on the Orbiter windward HRSI tile acreage, nose cap, and wing leading edge assuming localized highly catalytic or fully catalytic surfaces. The method incorporated the Boundary Layer Integral Matrix Procedure Kinetic (BLIMPK) code with streamline inputs from viscous Navier-Stokes solutions to produce heating rates for localized fully catalytic and highly catalytic surfaces as well as for nominal partially catalytic surfaces (either Reinforced Carbon-Carbon or Reaction Cured Glass) with temperature-dependent recombination coefficients. The highly catalytic heating results showed very good correlation with Orbiter Experiments STS-2, -3, and -5 centerline and STS-5 wing flight data for the HRSI tiles. Recommended catalytic heating factors were generated for use in future Shuttle missions in the event of quick-time analysis of damaged or repaired TPS areas during atmospheric reentry. The catalytic factors are presented along the streamlines as well as a function of stagnation enthalpy so they can be used for arbitrary trajectories.

Experimental Design for the Evaluation of Detection Techniques of Hidden Corrosion Beneath the Thermal Protective System of the Space Shuttle Orbiter

NASA Technical Reports Server (NTRS)

Kammerer, Catherine C.; Jacoby, Joseph A.; Lomness, Janice K.; Hintze, Paul E.; Russell, Richard W.

2007-01-01

The United States Space Operational Space Shuttle Fleet Consists of three shuttles with an average age of 19.7 years. Shuttles are exposed to corrosive conditions while undergoing final closeout for missions at the launch pad and extreme conditions during ascent, orbit, and descent that may accelerate the corrosion process. Structural corrosion under TPS could progress undetected (without tile removal) and eventually result in reduction in structural capability sufficient to create negative margins of . safety and ultimate loss of local structural capability.

Aerodynamic pressure and heating-rate distributions in tile gaps around chine regions with pressure gradients at a Mach number of 6.6

NASA Technical Reports Server (NTRS)

Hunt, L. Roane; Notestine, Kristopher K.

1990-01-01

Surface and gap pressures and heating-rate distributions were obtained for simulated Thermal Protection System (TPS) tile arrays on the curved surface test apparatus of the Langley 8-Foot High Temperature Tunnel at Mach 6.6. The results indicated that the chine gap pressures varied inversely with gap width because larger gap widths allowed greater venting from the gap to the lower model side pressures. Lower gap pressures caused greater flow ingress from the surface and increased gap heating. Generally, gap heating was greater in the longitudinal gaps than in the circumferential gaps. Gap heating decreased with increasing gap depth. Circumferential gap heating at the mid-depth was generally less than about 10 percent of the external surface value. Gap heating was most severe at local T-gap junctions and tile-to-tile forward-facing steps that caused the greatest heating from flow impingement. The use of flow stoppers at discrete locations reduced heating from flow impingement. The use of flow stoppers at discrete locations reduced heating in most gaps but increased heating in others. Limited use of flow stoppers or gap filler in longitudinal gaps could reduce gap heating in open circumferential gaps in regions of high surface pressure gradients.

SPRITE: A TPS Test Bed for Ground and Flight

NASA Technical Reports Server (NTRS)

Prabhu, Dinesh K.; Agrawal, Parul; Peterson, Keith; Swanson, Gregory; Skokova, Kristina; Mangini, Nancy; Empey, Daniel M.; Gorbunov, Sergey; Venkatapathy, Ethiraj

2012-01-01

Engineers in the Entry Systems and Technology Division at NASA Ames Research Center developed a fully instrumented, small atmospheric entry probe called SPRITE (Small Probe Reentry Investigation for TPS Engineering). SPRITE, conceived as a flight test bed for thermal protection materials, was tested at full scale in an arc-jet facility so that the aerothermal environments the probe experiences over portions of its flight trajectory and in the arc-jet are similar. This ground-to-flight traceability enhances the ability of mission designers to evaluate margins needed in the design of thermal protection systems (TPS) of larger scale atmospheric entry vehicles. SPRITE is a 14-inch diameter, 45 deg. sphere-cone with a conical aftbody and designed for testing in the NASA Ames Aerodynamic Heating Facility (AHF). The probe is a two-part aluminum shell with PICA (phenolic impregnated carbon ablator) bonded on the forebody and LI-2200 (Shuttle tile material) bonded to the aftbody. Plugs with embedded thermocouples, similar to those installed in the heat shield of the Mars Science Laboratory (MSL), and a number of distributed sensors are integrated into the design. The data from these sensors are fed to an innovative, custom-designed data acquisition system also integrated with the test article. Two identical SPRITE models were built and successfully tested in late 2010-early 2011, and the concept is currently being modified to enable testing of conformable and/or flexible materials.

New Approach for Thermal Protection System of a Probe During Entry

NASA Technical Reports Server (NTRS)

Yendler, Boris; Poffenbarger, Nathan; Patel, Amisha; Bhave, Ninad; Papadopoulos, Periklis

2005-01-01

One of the biggest challenges for any thermal protection system (TPS) of a probe is to provide a sufficient barrier for heat generated during descent in order to keep the temperature inside of the probe low enough to support operational temperature of equipment. Typically, such a goal is achieved by having the ceramic tiles and blankets like on the Space Shuttle, silicon based ablators, or metallic systems to cover the probe external surface. This paper discusses the development of an innovative technique for TPS of the probe. It is proposed to use a novel TPS which comprises thermal management of the entry vehicle. It includes: a) absorption of the heat during heat pick load by a Phase Change Material (PCM), b) separation of the compartment which contains PCM from the rest of the space vehicle by a gap with a high thermal resistance, c) maintaining temperature of the internal wall of s/c cabin temperature by transfer heat from the internal wall to the "cold" side of the vehicle and to reject heat into the space during the flight and on a ground, d) utilization of an advanced heat pipe, so called Loop Heat Pipe to transfer heat from the cabin internal wall to the cold side of the s/c and to reject the heat into environment outside of the vehicle. A Loop Heat Pipe is capable of transferring heat against gravity

Materials Testing on the DC-X and DC-XA

NASA Technical Reports Server (NTRS)

Smith, Dane; Carroll, Carol; Marschall, Jochen; Pallix, Joan

1997-01-01

Flight testing of thermal protection materials has been carried out over a two year period on the base heat shield of the Delta Clipper (DC-X and DC-XA), as well on a body flap. The purpose was to use the vehicle as a test bed for materials and more efficient repair or maintenance processes which would be potentially useful for application on new entry vehicles (i.e., X-33, RLV, planetary probes), as well as on the existing space shuttle orbiters. Panels containing Thermal Protection Systems (TPS) and/or structural materials were constructed either at NASA Ames Research Center or at McDonnell Douglas Aerospace (MDA) and attached between two of the four thrusters in the base heat shield of the DC-X or DC-XA. Three different panels were flown on DC-X flights 6, 7, and 8. A total of 7 panels were flown on DC-XA flights 1, 2, and 3. The panels constructed at Ames contained a variety of ceramic TPS including flexible blankets, tiles with high emissivity coatings, lightweight ceramic ablators and other ceramic composites. The MDS test panels consisted primarily of a variety of metallic composites. This report focuses on the ceramic TPS test results.

Testing of Advanced Conformal Ablative TPS

NASA Technical Reports Server (NTRS)

Gasch, Matthew; Agrawal, Parul; Beck, Robin

2013-01-01

In support of the CA250 project, this paper details the results of a test campaign that was conducted at the Ames Arcjet Facility, wherein several novel low density thermal protection (TPS) materials were evaluated in an entry like environment. The motivation for these tests was to investigate whether novel conformal ablative TPS materials can perform under high heat flux and shear environment as a viable alternative to rigid ablators like PICA or Avcoat for missions like MSL and beyond. A conformable TPS over a rigid aeroshell has the potential to solve a number of challenges faced by traditional rigid TPS materials (such as tiled Phenolic Impregnated Carbon Ablator (PICA) system on MSL, and honeycomb-based Avcoat on the Orion Multi Purpose Crew Vehicle (MPCV)). The compliant (high strain to failure) nature of the conformable ablative materials will allow better integration of the TPS with the underlying aeroshell structure and enable monolithic-like configuration and larger segments to be used in fabrication.A novel SPRITE1 architecture, developed by the researchers at NASA Ames was used for arcjet testing. This small probe like configuration with 450 spherecone, enabled us to test the materials in a combination of high heat flux, pressure and shear environment. The heat flux near the nose were in the range of 500-1000 W/sq cm whereas in the flank section of the test article the magnitudes were about 50 of the nose, 250-500W/sq cm range. There were two candidate conformable materials under consideration for this test series. Both test materials are low density (0.28 g/cu cm) similar to Phenolic Impregnated Carbon Ablator (PICA) or Silicone Impregnated Refractory Ceramic Ablator (SIRCA) and are comprised of: A flexible carbon substrate (Carbon felt) infiltrated with an ablative resin system: phenolic (Conformal-PICA) or silicone (Conformal-SICA). The test demonstrated a successful performance of both the conformable ablators for heat flux conditions between 50-500 W/sq cm. The recession and temperature profile for these materials were comparable to PICA proving them to be viable alternatives for TPS technology development for future missions.

Atlantis TPS Processing

NASA Image and Video Library

2003-10-01

In the Orbiter Processing Facility, Harrell Watts (left), with United Space Alliance, removes a tile from the thermal barrier around the umbilical areas, the external tank attach points, on the underside of Atlantis. The umbilical areas are closed off after ET separation by a door, seen here. The exposed area of each closed door is covered with reusable surface insulation.

Development of Low Density Flexible Carbon Phenolic Ablators

NASA Technical Reports Server (NTRS)

Stackpole, Mairead; Thornton, Jeremy; Fan, Wendy; Agrawal, Parul; Doxtad, Evan; Gasch, Matt

2011-01-01

Phenolic Impregnated Carbon Ablator (PICA) was the enabling TPS material for the Stardust mission where it was used as a single piece heatshield. PICA has the advantages of low density (0.27g/cm3) coupled with efficient ablative capability at high heat fluxes. Under the Orion program, PICA was also shown to be capable of both ISS and lunar return missions however some unresolved issues remain for its application in a tiled configuration for the Orion-specific design. In particular, the problem of developing an appropriate gap filler resulted in the Orion program selecting AVCOAT as the primary heatshield material over PICA. We are currently looking at alternative architectures to yield flexible and more conformal carbon phenolic materials with comparable densities to PICA that will address some of the design issues faced in the application of a tiled PICA heat shield. These new materials are viable TPS candidates for upcoming NASA missions and as material candidates for private sector Commercial Orbital Transportation Services (COTS). This presentation will discuss flexible alternatives to PICA and include preliminary mechanical and thermal properties as well as arc jet and LHMEL screening test results.

KSC-07pd1494

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- Another view of the area of orbiter Endeavour's orbital maneuvering system, or OMS, pod where the tear occurred on Atlantis during launch of mission STS-117 on June 8, 2007. Repair is under consideration following testing at KSC and Houston. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles were flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Photo credit: NASA/Kim Shiflett

KSC-07pd1495

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- Another view of the area of orbiter Endeavour's orbital maneuvering system, or OMS, pod where the tear occurred on Atlantis during launch of mission STS-117 on June 8, 2007. Repair is under consideration following testing at KSC and Houston. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles were flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Photo credit: NASA/Kim Shiflett

KSC-04pd1842

NASA Image and Video Library

2004-09-18

KENNEDY SPACE CENTER, FLA. - NASA Administrator Sean O’Keefe looks at equipment moved from the Thermal Protection System Facility to the RLV Hangar. AT right is Martin Wilson, manager of TPS operations for United Space Alliance. O’Keefe and NASA Associate Administrator of Space Operations Mission Directorate William Readdy are visiting KSC to survey the damage sustained by KSC facilities from Hurricane Frances. The Thermal Protection System Facility (TPSF), which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof in the storm, which blew across Central Florida Sept. 4-5. Undamaged equipment was removed from the TPSF and stored in the hangar. The Labor Day storm also caused significant damage to the Vehicle Assembly Building and Processing Control Center. Additionally, the Operations and Checkout Building, Vertical Processing Facility, Hangar AE, Hangar S and Hangar AF Small Parts Facility each received substantial damage. However, well-protected and unharmed were NASA’s three Space Shuttle orbiters -- Discovery, Atlantis and Endeavour - along with the Shuttle launch pads, all of the critical flight hardware for the orbiters and the International Space Station, and NASA’s Swift spacecraft that is awaiting launch in October.

Evaluation of electrostatic charge effects on the data processing system and the orbiter communication and tracking receivers

NASA Technical Reports Server (NTRS)

Lawton, R. M.

1975-01-01

An analysis of radiated interference test results obtained from frictionally charged Orbiter TPS tile was presented. The tests included the measurement of noise pick-up by Orbiter S-band, L-band, C-band, and Ku-band antennas located beneath the tiles in a manner simulating their installation on Orbiter. In addition, the radiated field characteristics resulting from the static discharge was determined. The results are analyzed as to their effect on data bus equipment and on Orbiter Communications and Tracking (C&T) receivers. It was concluded that the radiated interference should have no effect on MDM's. However the CPU, IOP and PMU enclosures require some minor modification to assure immunity from P-static interference. Orbiter antenna tests indicate that the S-band receiver should not be affected by P-static noise. The TACAN and Radar Altimeter performance appears to be adequate but with a small margin. MSBLS performance is uncertain because laboratory instrumentation cannot approach the MSBLS sensitivity.

KSC-07pd1491

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepared three test articles that will be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles were flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Photo credit: NASA/Kim Shiflett

Progress Report on PICA Activities in Support of New Frontiers Missions

NASA Technical Reports Server (NTRS)

Stackpoole, Margaret; Venkatapathy, Ethiraj; Violette, Steve

2017-01-01

Phenolic Impregnated Carbon Ablator (PICA) is a TPS material that has been used in a number of previous flight missions (Stardust, MSL) and is planned for a number of future missions (OSIRIS-Rex and Mars 2020) so it has substantial flight heritage, is applicable to a wide range of missions, and is often baselined as the TPS in future NASA proposal activities. As is common with a number of TPS materials, PICA faces a supply chain issue with the rayon precursor from which the carbon fibers used in the PICA preform are derived. PICA uses a non-woven form of the rayon, which once carbonized, is used in the low-density carbon FiberForm (carbon tile) preform utilized in PICA. Current PICA uses a NASA-qualified non-domestic rayon supplier (Sniace), however the qualified supplier is no longer manufacturing the rayon materials. This activity will address PICA sustainability, by initially carbonizing the remaining stockpile of Sniace rayon precursor. A additional FiberForm manufacturing task from alternate rayon sources is also in progress.

KSC-04pd1783

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - In the RLV hangar at KSC, Terri McCall cleans up equipment removed from the hurricane-ravaged Thermal Protection System Facility (TPSF). The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1780

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - In the RLV hangar at KSC, United Space Alliance worker Steve Mitchell unpacks equipment that was removed from the hurricane-ravaged Thermal Protection System Facility (TPSF). The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1849

NASA Image and Video Library

2004-09-18

KENNEDY SPACE CENTER, FLA. - Martin Wilson (far left), manager of Thermal Protection System (TPS) operations for United Space Alliance (USA), leads NASA Administrator Sean O’Keefe (second from left) on a tour of the hurricane-ravaged Thermal Protection System Facility. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof in the storm, which blew across Central Florida Sept. 4-5. Undamaged equipment was removed from the TPSF and stored in the RLV hangar. O’Keefe and NASA Associate Administrator of Space Operations Mission Directorate William Readdy are visiting KSC to survey the damage sustained by KSC facilities from the hurricane. The Labor Day storm also caused significant damage to the Vehicle Assembly Building and Processing Control Center. Additionally, the Operations and Checkout Building, Vertical Processing Facility, Hangar AE, Hangar S and Hangar AF Small Parts Facility each received substantial damage. However, well-protected and unharmed were NASA’s three Space Shuttle orbiters - Discovery, Atlantis and Endeavour - along with the Shuttle launch pads, all of the critical flight hardware for the orbiters and the International Space Station, and NASA’s Swift spacecraft that is awaiting launch in October.

KSC-04pd1850

NASA Image and Video Library

2004-09-18

KENNEDY SPACE CENTER, FLA. - Martin Wilson (left, in foreground), manager of Thermal Protection System (TPS) operations for United Space Alliance (USA), gives a tour of the hurricane-ravaged Thermal Protection System Facility to (from center) NASA Associate Administrator of Space Operations Mission Directorate William Readdy, NASA Administrator Sean O’Keefe, Center Director James Kennedy and Director of Shuttle Processing Michael E. Wetmore. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof during Hurricane Frances, which blew across Central Florida Sept. 4-5. O’Keefe and Readdy are visiting KSC to survey the damage sustained by KSC facilities from the hurricane. The Labor Day storm also caused significant damage to the Vehicle Assembly Building and Processing Control Center. Additionally, the Operations and Checkout Building, Vertical Processing Facility, Hangar AE, Hangar S and Hangar AF Small Parts Facility each received substantial damage. However, well-protected and unharmed were NASA’s three Space Shuttle orbiters - Discovery, Atlantis and Endeavour - along with the Shuttle launch pads, all of the critical flight hardware for the orbiters and the International Space Station, and NASA’s Swift spacecraft that is awaiting launch in October.

KSC-04PD-1785

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. In the RLV hangar at KSC, Steve Harrington talks to workers about the equipment removed from the hurricane-ravaged Thermal Protection System Facility (TPSF) now being stored in the hangar. The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04PD-1782

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. In the RLV hangar at KSC, United Space Alliance workers Frank Rhodes and Lynn Rosenbauer look at wrapped material removed from the hurricane-ravaged Thermal Protection System Facility (TPSF). The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04PD-1777

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. United Space Alliance workers Dallas Lewis (left) and Damon Petty carry out equipment from the Thermal Protection System Facility (TPSF). The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. Undamaged equipment is being moved to the RLV hangar at KSC. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1788

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - In the RLV hangar at KSC, Kevin Harrington, manager of Softgoods Production, talks to workers about the equipment removed from the hurricane-ravaged Thermal Protection System Facility (TPSF) now being stored in the hangar. The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1792

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - In the RLV hangar at KSC, United Space Alliance workers set up shelves for equipment removed from the hurricane-ravaged Thermal Protection System Facility (TPSF) and now being stored in the hangar. The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1786

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - In the RLV hangar at KSC, Steve Harrington talks to workers about the equipment removed from the hurricane-ravaged Thermal Protection System Facility (TPSF) now being stored in the hangar. The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1785

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - In the RLV hangar at KSC, Steve Harrington talks to workers about the equipment removed from the hurricane-ravaged Thermal Protection System Facility (TPSF) now being stored in the hangar. The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1779

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - United Space Alliance worker Janet Mills stores equipment removed from the hurricane-ravaged Thermal Protection System Facility (TPSF) in the RLV hangar at KSC. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. Undamaged equipment has been moved to the hangar. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1782

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - In the RLV hangar at KSC, United Space Alliance workers Frank Rhodes and Lynn Rosenbauer look at wrapped material removed from the hurricane-ravaged Thermal Protection System Facility (TPSF). The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1777

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - United Space Alliance workers Dallas Lewis (left) and Damon Petty carry out equipment from the Thermal Protection System Facility (TPSF). The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. Undamaged equipment is being moved to the RLV hangar at KSC. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1784

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - In the RLV hangar at KSC, United Space Alliance workers Matt Carter (left) and Mike Sherman set up racks to hold equipment removed from the hurricane-ravaged Thermal Protection System Facility (TPSF). The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1781

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - In the RLV hangar at KSC, United Space Alliance workers Beth Smith (left) and Theresa Haygood unwrap equipment removed from the hurricane-ravaged Thermal Protection System Facility (TPSF). The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1845

NASA Image and Video Library

2004-09-18

KENNEDY SPACE CENTER, FLA. - - United Space Alliance technician Shelly Kipp (right) shows some of the material salvaged from the storm-ravaged Thermal Protection System Facility (TPSF) to NASA Administrator Sean O’Keefe (left). Martin Wilson (center), manager of TPS operations for USA, looks on. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof during Hurricane Frances, which blew across Central Florida Sept. 4-5. O’Keefe and NASA Associate Administrator of Space Operations Mission Directorate William Readdy are visiting KSC to survey the damage sustained by KSC facilities from the hurricane. Undamaged equipment was removed from the TPSF and stored in the RLV hangar. The Labor Day storm also caused significant damage to the Vehicle Assembly Building and Processing Control Center. Additionally, the Operations and Checkout Building, Vertical Processing Facility, Hangar AE, Hangar S and Hangar AF Small Parts Facility each received substantial damage. However, well-protected and unharmed were NASA’s three Space Shuttle orbiters -- Discovery, Atlantis and Endeavour - along with the Shuttle launch pads, all of the critical flight hardware for the orbiters and the International Space Station, and NASA’s Swift spacecraft that is awaiting launch in October.

KSC-07pd2188

NASA Image and Video Library

2007-08-03

KENNEDY SPACE CENTER, FLA. - The STS-120 crew is at Kennedy for a crew equipment interface test, or CEIT. Inspecting the thermal protection system, or TPS, tiles under space shuttle Discovery in Orbiter Processing Facility bay 3 are, from left, Expedition 16 Flight Engineer Daniel M. Tani; Mission Specialist Douglas H. Wheelock; Pilot George D. Zamka; Mission Specialist Paolo A. Nespoli, a European Space Agency astronaut from Italy; Allison Bolinger, an EVA technician with NASA; Mission Specialists Scott E. Parazynski and Stephanie D. Wilson; and Erin Schlichenmaier, of TPS Engineering with United Space Alliance. Among the activities standard to a CEIT are harness training, inspection of the thermal protection system and camera operation for planned extravehicular activities, or EVAs. The STS-120 mission will deliver the Harmony module, christened after a school contest, which will provide attachment points for European and Japanese laboratory modules on the International Space Station. Known in technical circles as Node 2, it is similar to the six-sided Unity module that links the U.S. and Russian sections of the station. Built in Italy for the United States, Harmony will be the first new U.S. pressurized component to be added. The STS-120 mission is targeted to launch on Oct. 20. Photo credit: NASA/George Shelton

KSC-07pd2191

NASA Image and Video Library

2007-08-03

KENNEDY SPACE CENTER, FLA. - The STS-120 crew is at Kennedy for a crew equipment interface test, or CEIT. Inspecting the thermal protection system, or TPS, tiles under space shuttle Discovery in Orbiter Processing Facility bay 3 are, from left, Expedition 16 Flight Engineer Daniel M. Tani; Mission Specialist Douglas H. Wheelock; Pilot George D. Zamka; Mission Specialist Paolo A. Nespoli (kneeling), a European Space Agency astronaut from Italy; Mission Specialist Scott E. Parazynski; Commander Pamela A. Melroy; Allison Bolinger (kneeling), an EVA technician with NASA; Mission Specialist Stephanie D. Wilson; and Erin Schlichenmaier, with United Space Alliance TPS Engineering. Among the activities standard to a CEIT are harness training, inspection of the thermal protection system and camera operation for planned extravehicular activities, or EVAs. The STS-120 mission will deliver the Harmony module, christened after a school contest, which will provide attachment points for European and Japanese laboratory modules on the International Space Station. Known in technical circles as Node 2, it is similar to the six-sided Unity module that links the U.S. and Russian sections of the station. Built in Italy for the United States, Harmony will be the first new U.S. pressurized component to be added. The STS-120 mission is targeted to launch on Oct. 20. Photo credit: NASA/George Shelton

KSC-07pd2189

NASA Image and Video Library

2007-08-03

KENNEDY SPACE CENTER, FLA. - The STS-120 crew is at Kennedy for a crew equipment interface test, or CEIT. Inspecting the thermal protection system, or TPS, tiles under space shuttle Discovery in Orbiter Processing Facility bay 3 are, from left, Mission Specialist Douglas H. Wheelock (standing); Pilot George D. Zamka; Mission Specialist Paolo A. Nespoli, a European Space Agency astronaut from Italy; Allison Bolinger (pointing), an EVA technician with NASA; Commander Pamela A. Melroy; Mission Specialists Scott E. Parazynski and Stephanie D. Wilson; two support personnel and Erin Schlichenmaier, with United Space Alliance TPS Engineering. Among the activities standard to a CEIT are harness training, inspection of the thermal protection system and camera operation for planned extravehicular activities, or EVAs. The STS-120 mission will deliver the Harmony module, christened after a school contest, which will provide attachment points for European and Japanese laboratory modules on the International Space Station. Known in technical circles as Node 2, it is similar to the six-sided Unity module that links the U.S. and Russian sections of the station. Built in Italy for the United States, Harmony will be the first new U.S. pressurized component to be added. The STS-120 mission is targeted to launch on Oct. 20. Photo credit: NASA/George Shelton

KSC-07pd2190

NASA Image and Video Library

2007-08-03

KENNEDY SPACE CENTER, FLA. - The STS-120 crew is at Kennedy for a crew equipment interface test, or CEIT. Inspecting the thermal protection system, or TPS, tiles under space shuttle Discovery in Orbiter Processing Facility bay 3 are, from left, Expedition 16 Flight Engineer Daniel M. Tani; Mission Specialist Douglas H. Wheelock; Pilot George D. Zamka; Mission Specialist Paolo A. Nespoli (sitting), a European Space Agency astronaut from Italy; Mission Specialist Scott E. Parazynski (pointing); Commander Pamela A. Melroy; Allison Bolinger (kneeling), an EVA technician with NASA; Mission Specialist Stephanie D. Wilson; and Erin Schlichenmaier, with United Space Alliance TPS Engineering. Among the activities standard to a CEIT are harness training, inspection of the thermal protection system and camera operation for planned extravehicular activities, or EVAs. The STS-120 mission will deliver the Harmony module, christened after a school contest, which will provide attachment points for European and Japanese laboratory modules on the International Space Station. Known in technical circles as Node 2, it is similar to the six-sided Unity module that links the U.S. and Russian sections of the station. Built in Italy for the United States, Harmony will be the first new U.S. pressurized component to be added. The STS-120 mission is targeted to launch on Oct. 20. Photo credit: NASA/George Shelton

SAFER Inspection of Space Shuttle Thermal Protection System

NASA Technical Reports Server (NTRS)

Scoville, Zebulon C.; Rajula, Sudhakar

2005-01-01

In the aftermath of the space shuttle Columbia accident, it quickly became clear that new methods would need to be developed that would provide the capability to inspect and repair the shuttle's thermal protection system (TPS). A boom extension to the Remote Manipulator System (RMS) with a laser topography sensor package was identified as the primary means for measuring the damage depth in acreage tile as well as scanning Reinforced Carbon- Carbon (RCC) surfaces. However, concern over the system's fault tolerance made it prudent to investigate alternate means of acquiring close range photographs and contour depth measurements in the event of a failure. One method that was identified early was to use the Simplified Aid For EVA Rescue (SAFER) propulsion system to allow EVA access to damaged areas of concern. Several issues were identified as potential hazards to SAFER use for this operation. First, the ability of an astronaut to maintain controlled flight depends upon efficient technique and hardware reliability. If either of these is insufficient during flight operations, a safety tether must be used to rescue the crewmember. This operation can jeopardize the integrity of the Extra-vehicular Mobility Unit (EMU) or delicate TPS materials. Controls were developed to prevent the likelihood of requiring a tether rescue, and procedures were written to maximize the chances for success if it cannot be avoided. Crewmember ability to manage tether cable tension during nominal flight also had to be evaluated to ensure it would not negatively affect propellant consumption. Second, although propellant consumption, flight control, orbital dynamics, and flight complexity can all be accurately evaluated in Virtual Reality (VR) Laboratory at Johnson Space Center, there are some shortcomings. As a crewmember's hand is extended to simulate measurement of tile damage, it will pass through the vehicle without resistance. In reality, this force will push the crewmember away from the vehicle, and could induce a moment which, if strong enough, could saturate the attitude control system in SAFER. This raises the concern that additional propellant will be consumed to maintain controlled flight. To account for this, the fidelity of the Virtual Reality simulation was improved to include the effect of crewmember contact with the vehicle during SAFER flight. In addition, while participating in VR simulations, the subject is in shirt sleeves and sits in a chair. This does not provide a flight-like representation of body position awareness. To prevent inadvertent contact with tile or RCC, other facilities were utilized to establish crew preferences for body attitude and tool configuration. Finally, a study was performed to determine if attitude constraints are needed for the Space shuttle and International Space Station to reduce SAFER flight difficulty.

Wireless Subsurface Sensors for Health Monitoring of Thermal Protection Systems on Hypersonic Vehicles

NASA Technical Reports Server (NTRS)

Milos, Frank S.; Arnold, Jim (Technical Monitor)

2001-01-01

Health diagnostics is an area where major improvements have been identified for potential implementation into the design of new reusable launch vehicles (RLVs) in order to reduce life cycle costs, to increase safety margins, and to improve mission reliability. NASA Ames is leading the effort to develop inspection and health management technologies for thermal protection systems. This paper summarizes a joint project between NASA Ames and industry partners to develop "wireless" devices that can be embedded in the thermal protection system to monitor temperature or other quantities of interest. These devices are sensors integrated with radio-frequency identification (RFID) microchips to enable non-contact communication of sensor data to an external reader that may be a hand-held scanner or a large portal. Both passive and active prototype devices have been developed. The passive device uses a thermal fuse to indicate the occurrence of excessive temperature. This device has a diameter under 0.13 cm. (suitable for placement in gaps between ceramic TPS tiles on an RLV) and can withstand 370 C for 15 minutes. The active device contains a small battery to provide power to a thermocouple for recording a temperature history during flight. The bulk of the device must be placed beneath the TPS for protection from high temperature, but the thermocouple can be placed in a hot location such as near the external surface.

System Specificity of the TpsB Transporters of Coexpressed Two-Partner Secretion Systems of Neisseria meningitidis

PubMed Central

ur Rahman, Sadeeq

2013-01-01

The two-partner secretion (TPS) systems of Gram-negative bacteria consist of a large secreted exoprotein (TpsA) and a transporter protein (TpsB) located in the outer membrane. TpsA targets TpsB for transport across the membrane via its ∼30-kDa TPS domain located at its N terminus, and this domain is also the minimal secretory unit. Neisseria meningitidis genomes encode up to five TpsAs and two TpsBs. Sequence alignments of TPS domains suggested that these are organized into three systems, while there are two TpsBs, which raised questions on their system specificity. We show here that the TpsB2 transporter of Neisseria meningitidis is able to secrete all types of TPS domains encoded in N. meningitidis and the related species Neisseria lactamica but not domains of Haemophilus influenzae and Pseudomonas aeruginosa. In contrast, the TpsB1 transporter seemed to be specific for its cognate N. meningitidis system and did not secrete the TPS domains of other meningococcal systems. However, TpsB1 did secrete the TPS2b domain of N. lactamica, which is related to the meningococcal TPS2 domains. Apparently, the secretion depends on specific sequences within the TPS domain rather than the overall TPS domain structure. PMID:23222722

Orion EFT-1 Catalytic Tile Experiment Overview and Flight Measurements

NASA Technical Reports Server (NTRS)

Salazar, Giovanni; Amar, Adam; Hyatt, Andrew; Rezin, Marc D.

2016-01-01

This paper describes the design and results of a surface catalysis flight experiment flown on the Orion Multipurpose Crew Vehicle during Exploration Flight Test 1 (EFT1). Similar to previous Space Shuttle catalytic tile experiments, the present test consisted of a highly catalytic coating applied to an instrumented TPS tile. However, the present catalytic tile experiment contained significantly more instrumentation in order to better resolve the heating overshoot caused by the change in surface catalytic efficiency at the interface between two distinct materials. In addition to collecting data with unprecedented spatial resolution of the "overshoot" phenomenon, the experiment was also designed to prove if such a catalytic overshoot would be seen in turbulent flow in high enthalpy regimes. A detailed discussion of the results obtained during EFT1 is presented, as well as the challenges associated with data interpretation of this experiment. Results of material testing carried out in support of this flight experiment are also shown. Finally, an inverse heat conduction technique is employed to reconstruct the flight environments at locations upstream and along the catalytic coating. The data and analysis presented in this work will greatly contribute to our understanding of the catalytic "overshoot" phenomenon, and have a significant impact on the design of future spacecraft.

KSC-04PD-1776

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. United Space Alliance workers Dallas Lewis (left) and Damon Petty clean up hurricane debris inside the Thermal Protection System Facility (TPSF). Much of the roof was torn off by Hurricane Frances as it passed over Central Florida during the Labor Day weekend. Undamaged equipment has been moved to the RLV hangar at KSC. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

KSC-04pd1776

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - United Space Alliance workers Dallas Lewis (left) and Damon Petty clean up hurricane debris inside the Thermal Protection System Facility (TPSF). Much of the roof was torn off by Hurricane Frances as it passed over Central Florida during the Labor Day weekend. Undamaged equipment has been moved to the RLV hangar at KSC. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

Meningococcal Two-Partner Secretion Systems and Their Association with Outcome in Patients with Meningitis

PubMed Central

Piet, Jurgen R.; van Ulsen, Peter; ur Rahman, Sadeeq; Bovenkerk, Sandra; Bentley, Stephen D.

2016-01-01

Two-partner secretion (TPS) systems export large TpsA proteins to the surface and extracellular milieu. In meningococci, three different TPS systems exist, and of these, TPS system 2 (TPS2) and TPS3 can be detected by the host's immune system. We evaluated the distribution of TPS systems among clinical isolates from two prospective cohort studies comprising 373 patients with meningococcal meningitis. TPS system 1 was present in 91% of isolates, and system 2 and/or 3 was present in 67%. The TPS system distribution was related to clonal complexes. Infection with strains with TPS2 and/or TPS3 resulted in less severe disease and better outcomes than infection with strains without these systems. Using whole-blood stimulation experiments, we found no differences in the host cytokine response between patients infected with TPS system 2 and 3 knockout strains and patients infected with a wild-type strain. In conclusion, meningococcal TPS system 2 and/or 3 is associated with disease severity and outcome in patients with meningitis. PMID:27324486

Orion Flight Test-1 Thermal Protection System Instrumentation

NASA Technical Reports Server (NTRS)

Kowal, T. John

2011-01-01

The Orion Crew Exploration Vehicle (CEV) was originally under development to provide crew transport to the International Space Station after the retirement of the Space Shuttle, and to provide a means for the eventual return of astronauts to the Moon. With the current changes in the future direction of the United States human exploration programs, the focus of the Orion project has shifted to the project s first orbital flight test, designated Orion Flight Test 1 (OFT-1). The OFT-1 is currently planned for launch in July 2013 and will demonstrate the Orion vehicle s capability for performing missions in low Earth orbit (LEO), as well as extensibility beyond LEO for select, critical areas. Among the key flight test objectives are those related to validation of the re-entry aerodynamic and aerothermal environments, and the performance of the thermal protection system (TPS) when exposed to these environments. A specific flight test trajectory has been selected to provide a high energy entry beyond that which would be experienced during a typical low Earth orbit return, given the constraints imposed by the possible launch vehicles. This trajectory resulted from a trade study that considered the relative benefit of conflicting objectives from multiple subsystems, and sought to provide the maximum integrated benefit to the re-entry state-of-the-art. In particular, the trajectory was designed to provide: a significant, measureable radiative heat flux to the windward surface; data on boundary transition from laminar to turbulent flow; and data on catalytic heating overshoot on non-ablating TPS. In order to obtain the necessary flight test data during OFT-1, the vehicle will need to have an adequate quantity of instrumentation. A collection of instrumentation is being developed for integration in the OFT-1 TPS. In part, this instrumentation builds upon the work performed for the Mars Science Laboratory Entry, Descent and Landing Instrument (MEDLI) suite to instrument the OFT-1 ablative heat shield. The MEDLI integrated sensor plugs and pressure sensors will be adapted for compatibility with the Orion TPS design. The sensor plugs will provide in-depth temperature data to support aerothermal and TPS model correlation, and the pressure sensors will provide a flush air data system for validation of the entry and descent aerodynamic environments. In addition, a radiometer design will be matured to measure the radiative component of the reentry heating at two locations on the heat shield. For the back shell, surface thermocouple and pressure port designs will be developed and applied which build upon the heritage of the Space Shuttle Program for instrumentation of reusable surface insulation (RSI) tiles. The quantity and location of the sensors has been determined to balance the needs of the reentry disciplines with the demands of the hardware development, manufacturing and integration. Measurements which provided low relative value and presented significant engineering development effort were, unfortunately, eliminated. The final TPS instrumentation has been optimized to target priority test objectives. The data obtained will serve to provide a better understanding of reentry environments for the Orion capsule design, reduce margins, and potentially reduce TPS mass or provide TPS extensibility for alternative missions.

Material Behavior of Window 7 Carrier Panel Tiles and Thermal Pane Fragments Recovered from the Space Shuttle Columbia

NASA Astrophysics Data System (ADS)

Arellano, Brenda R.

Since the end of the space shuttle program, a new generation spacecraft has been developed to transport humans back into space. NASA's Orion will carry a crew beyond low-earth orbit and the exploration of Mars may be possible in the future. Space safety becomes significant with human spaceflight and the risks are high. However, aerospace materials may provide opportunities to prevent future disasters. When the space shuttle Columbia disintegrated during re-entry in 2001, thousands of debris were collected for analysis. In contrast, when the Challenger space shuttle broke apart in 1986, all shuttle debris were buried. These tragic disasters are reminders of the importance of proper material selection and the concern of their performance in service. This research focused on investigating the effects of the debris recovered from the Columbia space shuttle after re-entry and break-up. Many of the components encountered unforeseen extreme temperatures, vibrations, and high stresses. The Columbia debris contained unique characteristics that have yet to be examined and the components for this study are the thermal protection system (TPS) carrier panel tiles and the thermal pane glass from the starboard orbiter Window 7. The alterations endured by the debris was studied through forensic materials characterization to investigate material interactions, material degradation, and thermal consequences. These materials played an essential role in the operation of the orbiter as they protected the underlying structural materials of the shuttle and underwent extreme temperatures. The methods and procedures for analyzing the debris included non-destructive and destructive evaluations. Non-destructive evaluations involved visual inspection, photographic documentation, 3D modeling, and surface elemental composition. The destructive analysis consisted of sectioning, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results obtained revealed metallic and oxide formations, flow trajectory, and the presence of other space shuttle materials. Determining the conditions of the debris after break-up is valuable because new developments for future manned spacecraft will require TPS. These materials must be continued to be studied aggressively to provide risk assessment for future missions. The findings of this investigation will identify the alterations on the debris and determine if these TPS materials are reliable for future spacecraft.

Micromechanical analysis and design of an integrated thermal protection system for future space vehicles

NASA Astrophysics Data System (ADS)

Martinez, Oscar

Thermal protection systems (TPS) are the key features incorporated into a spacecraft's design to protect it from severe aerodynamic heating during high-speed travel through planetary atmospheres. The thermal protection system is the key technology that enables a spacecraft to be lightweight, fully reusable, and easily maintainable. Add-on TPS concepts have been used since the beginning of the space race. The Apollo space capsule used ablative TPS and the Space Shuttle Orbiter TPS technology consisted of ceramic tiles and blankets. Many problems arose from the add-on concept such as incompatibility, high maintenance costs, non-load bearing, and not being robust and operable. To make the spacecraft's TPS more reliable, robust, and efficient, we investigated Integral Thermal Protection System (ITPS) concept in which the load-bearing structure and the TPS are combined into one single component. The design of an ITPS was a challenging task, because the requirement of a load-bearing structure and a TPS are often conflicting. Finite element (FE) analysis is often the preferred method of choice for a structural analysis problem. However, as the structure becomes complex, the computational time and effort for an FE analysis increases. New structural analytical tools were developed, or available ones were modified, to perform a full structural analysis of the ITPS. With analytical tools, the designer is capable of obtaining quick and accurate results and has a good idea of the response of the structure without having to go to an FE analysis. A MATLABRTM code was developed to analytically determine performance metrics of the ITPS such as stresses, buckling, deflection, and other failure modes. The analytical models provide fast and accurate results that were within 5% difference from the FEM results. The optimization procedure usually performs 100 function evaluations for every design variable. Using the analytical models in the optimization procedure was a time saver, because the optimization time to reach an optimum design was reached in less than an hour, where as an FE optimization study would take hours to reach an optimum design. Corrugated-core structures were designed for ITPS applications with loads and boundary conditions similar to that of a Space Shuttle-like vehicle. Temperature, buckling, deflection and stress constraints were considered for the design and optimization process. An optimized design was achieved with consideration of all the constraints. The ITPS design obtained from the analytical solutions was lighter (4.38 lb/ft2) when compared to the ITPS design obtained from a finite element analysis (4.85 lb/ft 2). The ITPS boundary effects added local stresses and compressive loads to the top facesheet that was not able to be captured by the 2D plate solutions. The inability to fully capture the boundary effects lead to a lighter ITPS when compared to the FE solution. However, the ITPS can withstand substantially large mechanical loads when compared to the previous designs. Truss-core structures were found to be unsuitable as they could not withstand the large thermal gradients frequently encountered in ITPS applications.

KSC-04PD-1778

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. In the Columbia debris hangar at KSC, a United Space Alliance worker lines up air heaters salvaged from the hurricane-ravaged Thermal Protection System Facility (TPSF) in order to dry them out. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. Undamaged equipment has been moved to the RLV hangar at KSC. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

Orion Heat Shield Manufacturing Producibility Improvements for the EM-1 Flight Test Program

NASA Technical Reports Server (NTRS)

Koenig, William J.; Stewart, Michael; Harris, Richard F.

2018-01-01

This paper describes how the ORION program is incorporating improvements in the heat shield design and manufacturing processes reducing programmatic risk and ensuring crew safety in support of NASA's Exploration missions. The approach for the EFT-1 heat shield utilized a low risk Apollo heritage design and manufacturing process using an Avcoat TPS ablator with a honeycomb substrate to provide a one piece heat shield to meet the mission re-entry heating environments. The EM-1 mission will have additional flight systems installed to fly to the moon and return to Earth. Heat shield design and producibility improvements have been incorporated in the EM-1 vehicle to meet deep space mission requirements. The design continues to use the Avcoat material, but in a block configuration to enable improvements in consistant and repeatable application processes using tile bonding experience developed on the Space Shuttle Transportation System Program.

KSC-04pd1778

NASA Image and Video Library

2004-09-14

KENNEDY SPACE CENTER, FLA. - In the Columbia debris hangar at KSC, a United Space Alliance worker lines up air heaters salvaged from the hurricane-ravaged Thermal Protection System Facility (TPSF) in order to dry them out. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof due to Hurricane Frances, which blew across Central Florida Sept. 4-5. Undamaged equipment has been moved to the RLV hangar at KSC. The maximum wind at the surface from Hurricane Frances was 94 mph from the northeast at 6:40 a.m. on Sunday, September 5. It was recorded at a weather tower located on the east shore of the Mosquito Lagoon near the Cape Canaveral National Seashore. The highest sustained wind at KSC was 68 mph.

"TPSX: Thermal Protection System Expert and Material Property Database"

NASA Technical Reports Server (NTRS)

Squire, Thomas H.; Milos, Frank S.; Rasky, Daniel J. (Technical Monitor)

1997-01-01

The Thermal Protection Branch at NASA Ames Research Center has developed a computer program for storing, organizing, and accessing information about thermal protection materials. The program, called Thermal Protection Systems Expert and Material Property Database, or TPSX, is available for the Microsoft Windows operating system. An "on-line" version is also accessible on the World Wide Web. TPSX is designed to be a high-quality source for TPS material properties presented in a convenient, easily accessible form for use by engineers and researchers in the field of high-speed vehicle design. Data can be displayed and printed in several formats. An information window displays a brief description of the material with properties at standard pressure and temperature. A spread sheet window displays complete, detailed property information. Properties which are a function of temperature and/or pressure can be displayed as graphs. In any display the data can be converted from English to SI units with the click of a button. Two material databases included with TPSX are: 1) materials used and/or developed by the Thermal Protection Branch at NASA Ames Research Center, and 2) a database compiled by NASA Johnson Space Center 9JSC). The Ames database contains over 60 advanced TPS materials including flexible blankets, rigid ceramic tiles, and ultra-high temperature ceramics. The JSC database contains over 130 insulative and structural materials. The Ames database is periodically updated and expanded as required to include newly developed materials and material property refinements.

Data correlation and analysis of arc tunnel and wind tunnel tests of RSI joints and gaps, phase 2. Volume 1: Technical report

NASA Technical Reports Server (NTRS)

Cristensen, H. E.

1975-01-01

Heat transfer data measured in gaps representative of those being employed for joints in the space shuttle reusable surface insulation (RSI) thermal protection systems (TPS) were assimilated, analyzed, and correlated. Several types of gap were investigated with emphasis on simple butt joints. Gap widths ranged from 0.0 to 0.76 cm and depths ranged from 1 to 6 cm. Laminar, transitional, and turbulent boundary layer flows over the gap opening were investigated. The angle between gap axis and external flow was varied between 0 and pi/2 radians. The contoured cross section gap performed significantly better than all other wide gaps and slightly better than all other narrow gap geometries. Three dimensional heating variations were observed within gaps in the absence of external flow pressure gradients. Interactions between heating within gaps and heating of adjacent top tile surfaces were observed. Gaps aligned with the flow were observed to promote boundary layer transition. Heat transfer correlation equations were obtained for many of the tests. The TPS thickness requirements with and without gaps were computed for a current shuttle entry trajectory. Experimental data employed in the study are summarized. A description of each test facility, run schedule and test conditions, model descriptive information, and heat flux data are included.

Design of an integral thermal protection system for future space vehicles

NASA Astrophysics Data System (ADS)

Bapanapalli, Satish Kumar

Thermal protection systems (TPS) are the features incorporated into a spacecraft's design to protect it from severe aerodynamic heating during high-speed travel through planetary atmospheres. The ablative TPS on the space capsule Apollo and ceramic tiles and blankets on the Space Shuttle Orbiter were designed as add-ons to the main load-bearing structure of the vehicles. They are usually incompatible with the structure due to mismatch in coefficient of thermal expansion and as a result the robustness of the external surface of the spacecraft is compromised. This could potentially lead to catastrophic consequences because the TPS forms the external surface of the vehicle and is subjected to numerous other loads like aerodynamic pressure loads, small object high-speed impacts and handling damages during maintenance. In order to make the spacecraft external surface robust, an Integral Thermal Protection System (ITPS) concept has been proposed in this research in which the load-bearing structure and the TPS are combined into one single structure. The design of an ITPS is a formidable task because the requirement of a load-bearing structure and a TPS are often contradictory to one another. The design process has been formulated as an optimization problem with mass per unit area of the ITPS as the objective function and the various functions of the ITPS were formulated as constraints. This is a multidisciplinary design optimization problem involving heat transfer and structural analysis fields. The constraints were expressed as response surface approximations obtained from a large number of finite element analyses, which were carried out with combinations of design variables obtained from an optimized Latin-Hypercube sampling scheme. A MATLABRTM code has been developed to carry out these FE analyses automatically in conjunction with ABAQUSRTM . Corrugated-core structures were designed for ITPS applications with loads and boundary conditions similar to that of a Space Shuttle-like vehicle. Temperature, buckling, deflection and stress constraints were considered for the design process. An optimized mass ranging between 3.5--5 lb/ft2 was achieved by the design. This is considerably heavier when compared to conventional TPS designs. However, the ITPS can withstand substantially large mechanical loads when compared to the conventional TPS. Truss-core geometries used for ITPS design in this research were found to be unsuitable as they could not withstand large thermal gradients frequently encountered in ITPS applications. The corrugated-core design was used for further studying the influence of the various input parameters on the final design weight of the ITPS. It was observed that boundary conditions not only significantly influence the ITPS design but also have a major impact on the effect of various input parameters. It was found that even a small amount of heat loss from bottom face sheet leads to significant reduction in ITPS weight. Aluminum and Beryllium are the most suitable materials for bottom face sheet with Beryllium having considerable advantages in terms of heat capacity, stiffness and density. Although ceramic matrix composites have many superior properties when compared to metal alloys (Titanium alloys and Inconel), their low tensile strength presents difficulties in ITPS applications.

KSC-07pd1499

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepare test articles to be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

KSC-07pd1498

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepare test articles to be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

KSC-07pd1497

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepare test articles to be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

KSC-07pd1501

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepare test articles to be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

KSC-07pd1496

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- A United Space Alliance employee prepares a test article that will be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

KSC-07pd1500

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepare test articles to be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

Arcjet Tests of Different Gap-Filler Options for the Orion PICA Heatshield

NASA Technical Reports Server (NTRS)

Skokova, Kristina; Ellerby, Donald; Blosser, Max; Venkatapathy, Ethiraj; Bouslog, Stan; Reuther, James

2009-01-01

PICA (Phenolic Infiltrated Carbon Ablator) is one of the candidate thermal protection materials for the Orion vehicle. Because PICA is fabricated in blocks, gaps exist between the blocks, similar to the individual ceramic tiles of the Shuttle thermal protection system. The results of this work focus on arcjet test results of different gap-filler options for PICA, performed as part of the Orion TPS Advanced Development Project. The arcjet tests were performed at NASA Ames Research Center on stagnation models 4 inches in diameter at conditions representative of Orion flight conditions for both Lunar and Low Earth Orbit return. Performance of gap-filler options was evaluated based on the extent of backface temperature change, as compared to PICA without gaps, and on the extent of flow penetration into the gap, evident from the gap opening and widening.

Tales from the Mars Science Laboratory Thermal Protection System Development (or, Try Not to Panic When Your Heatshield Material Disappears)

NASA Technical Reports Server (NTRS)

Hwang, Helen H.

2018-01-01

In 2012, the entry vehicle for the Mars Science Laboratory (MSL) mission was the largest and heaviest vehicle flown to another planet, designed to be able to withstand the largest heat fluxes in the Martian atmosphere ever attempted. The heatshield material that had been successfully used for all previous Mars missions had been baselined in the design, but during the development and qualification testing demonstrated catastrophic and unexplained failures. With only 10 months remaining before the original launch date, the TPS team led by NASA Ames designed and implemented a first-ever tiled, ablative heatshield. Highlights from MSL of the testing difficulties and innovations required to execute a new heatshield design will be presented, along with a sneak peak of the Mars 2020 mission.

Modern Advances in Ablative TPS

NASA Technical Reports Server (NTRS)

Venkatapathy, Ethiraj

2013-01-01

Topics covered include: Physics of Hypersonic Flow and TPS Considerations. Destinations, Missions and Requirements. State of the Art Thermal Protection Systems Capabilities. Modern Advances in Ablative TPS. Entry Systems Concepts. Flexible TPS for Hypersonic Inflatable Aerodynamic Decelerators. Conformal TPS for Rigid Aeroshell. 3-D Woven TPS for Extreme Entry Environment. Multi-functional Carbon Fabric for Mechanically Deployable.

TPS In-Flight Health Monitoring Project Progress Report

NASA Technical Reports Server (NTRS)

Kostyk, Chris; Richards, Lance; Hudston, Larry; Prosser, William

2007-01-01

Progress in the development of new thermal protection systems (TPS) is reported. New approaches use embedded lightweight, sensitive, fiber optic strain and temperature sensors within the TPS. Goals of the program are to develop and demonstrate a prototype TPS health monitoring system, develop a thermal-based damage detection algorithm, characterize limits of sensor/system performance, and develop ea methodology transferable to new designs of TPS health monitoring systems. Tasks completed during the project helped establish confidence in understanding of both test setup and the model and validated system/sensor performance in a simple TPS structure. Other progress included complete initial system testing, commencement of the algorithm development effort, generation of a damaged thermal response characteristics database, initial development of a test plan for integration testing of proven FBG sensors in simple TPS structure, and development of partnerships to apply the technology.

Advanced Metallic Thermal Protection System Development

NASA Technical Reports Server (NTRS)

Blosser, M. L.; Chen, R. R.; Schmidt, I. H.; Dorsey, J. T.; Poteet, C. C.; Bird, R. K.

2002-01-01

A new Adaptable, Robust, Metallic, Operable, Reusable (ARMOR) thermal protection system (TPS) concept has been designed, analyzed, and fabricated. In addition to the inherent tailorable robustness of metallic TPS, ARMOR TPS offers improved features based on lessons learned from previous metallic TPS development efforts. A specific location on a single-stage-to-orbit reusable launch vehicle was selected to develop loads and requirements needed to design prototype ARMOR TPS panels. The design loads include ascent and entry heating rate histories, pressures, acoustics, and accelerations. Additional TPS design issues were identified and discussed. An iterative sizing procedure was used to size the ARMOR TPS panels for thermal and structural loads as part of an integrated TPS/cryogenic tank structural wall. The TPS panels were sized to maintain acceptable temperatures on the underlying structure and to operate under the design structural loading. Detailed creep analyses were also performed on critical components of the ARMOR TPS panels. A lightweight, thermally compliant TPS support system (TPSS) was designed to connect the TPS to the cryogenic tank structure. Four 18-inch-square ARMOR TPS panels were fabricated. Details of the fabrication process are presented. Details of the TPSS for connecting the ARMOR TPS panels to the externally stiffened cryogenic tank structure are also described. Test plans for the fabricated hardware are presented.

Baggie: A unique solution to an orbiter icing problem

NASA Technical Reports Server (NTRS)

Walkover, L. J.

1982-01-01

The orbiter icing problem, located in two lower surface mold line cavities, was solved. These two cavities are open during Shuttle ground operations and ascent, and are then closed after orbit insertion. If not protected, these cavities may be coated with ice, which may be detrimental to the adjacent thermal protection system (TPS) tiles if the ice breaks up during ascent, and may hinder the closing of the cavity doors if the ice does not break up. The problem of ice in these cavities was solved by the use of a passive mechanism called baggie, which is purge curtain used to enclose the cavity and is used in conjunction with gaseous nitrogen as the local purge gas. The baggie, the final solution, is unique in its simplicity, but its design and development were not. The final baggie design and its development testing are discussed. Also discussed are the baggie concepts and other solutions not used.

KSC-07pd2193

NASA Image and Video Library

2007-08-03

KENNEDY SPACE CENTER, FLA. - The STS-120 crew is at Kennedy for a crew equipment interface test, or CEIT. Inspecting the thermal protection system, or TPS, tiles under space shuttle Discovery in Orbiter Processing Facility bay 3 is Mission Specialist Paolo A. Nespoli, a European Space Agency astronaut from Italy. Among the activities standard to a CEIT are harness training, inspection of the thermal protection system and camera operation for planned extravehicular activities, or EVAs. The STS-120 mission will deliver the Harmony module, christened after a school contest, which will provide attachment points for European and Japanese laboratory modules on the International Space Station. Known in technical circles as Node 2, it is similar to the six-sided Unity module that links the U.S. and Russian sections of the station. Built in Italy for the United States, Harmony will be the first new U.S. pressurized component to be added. The STS-120 mission is targeted to launch on Oct. 20. Photo credit: NASA/George Shelton

KSC-07pd2192

NASA Image and Video Library

2007-08-03

KENNEDY SPACE CENTER, FLA. - The STS-120 crew is at Kennedy for a crew equipment interface test, or CEIT. Inspecting the thermal protection system, or TPS, tiles under space shuttle Discovery in Orbiter Processing Facility bay 3 is Mission Specialist Scott E. Parazynski, the lead spacewalker on the mission. Among the activities standard to a CEIT are harness training, inspection of the thermal protection system and camera operation for planned extravehicular activities, or EVAs. The STS-120 mission will deliver the Harmony module, christened after a school contest, which will provide attachment points for European and Japanese laboratory modules on the International Space Station. Known in technical circles as Node 2, it is similar to the six-sided Unity module that links the U.S. and Russian sections of the station. Built in Italy for the United States, Harmony will be the first new U.S. pressurized component to be added. The STS-120 mission is targeted to launch on Oct. 20. Photo credit: NASA/George Shelton

KSC-07pd2198

NASA Image and Video Library

2007-08-03

KENNEDY SPACE CENTER, FLA. - The STS-120 crew is at Kennedy for a crew equipment interface test, or CEIT. Receiving a briefing on the thermal protection system, or TPS, tiles on space shuttle Discovery in Orbiter Processing Facility bay 3 are Commander Pamela A. Melroy and Mission Specialist Paolo A. Nespoli, a European Space Agency astronaut from Italy. Among the activities standard to a CEIT are harness training, inspection of the thermal protection system and camera operation for planned extravehicular activities, or EVAs. The STS-120 mission will deliver the Harmony module, christened after a school contest, which will provide attachment points for European and Japanese laboratory modules on the International Space Station. Known in technical circles as Node 2, it is similar to the six-sided Unity module that links the U.S. and Russian sections of the station. Built in Italy for the United States, Harmony will be the first new U.S. pressurized component to be added. The STS-120 mission is targeted to launch on Oct. 20. Photo credit: NASA/George Shelton

Shock-induced flow separation and the orbiter thermal protection system

NASA Astrophysics Data System (ADS)

Waiter, S.-A.

The Space Shuttle orbiter's thermal protection system (TPS) is composed of reusable tiles separated by narrow gaps that accommodate the contraction and expansion of the aluminum structure that the tiles protect. When local pressure gradients exist, air flows through the tile gaps and releases heat energy by convection. The gaps represent a heat short to the structure, strain isolator pad (SIP), and filler bar. A typical problem is the pressure gradient created during entry by body flap deflection. After a brief description of how this problem affects the Space Shuttle orbiter, a theoretical and experimental review of the major parameters involved in gap heating are analyzed. Then, a review of well-known classical methods to resolve the gap aeroheating problem in the presence of a pressure gradient is presented, and a few solutions are illustrated to assess the sensitivity of each one. The following section starts with a basic relationship (called "eyeball" because of its simplicity) and follows the results up through the most modern engineering approach available in the literature. It shows that in all cases calculated significant areas of overtemperature were predicted. However, none of these methods could be correlated by experimental data. Lastly, the paper presents the solution obtained by using the most sophisticated method, based upon the Navier-Stokes equations. This approach shows excellent correlation with wind tunnel data. The application to four trajectory time points shows less severe results than the other methods. This can be explained by the introduction of a certain amount of conservatism to account for uncertainties inherent in the previous analyses. No correlation of this "exact solution" with the simple preestablished relationships has been found, indicating that more parameters than expected could be involved. However, an after-the-fact, semi-empirical engineering solution that fits the Navier-Stokes solution with good agreement was established.

Evaluation of a virtual pet visit system with live video streaming of patient images over the Internet in a companion animal intensive care unit in the Netherlands.

PubMed

Robben, Joris H; Melsen, Diede N; Almalik, Osama; Roomer, Wendy; Endenburg, Nienke

2016-05-01

To evaluate the impact of a virtual pet visit system ("TelePet" System, TPS) on owners and staff of a companion animal ICU. Longitudinal interventional study (2010-2013). Companion animal ICU at a university veterinary medical teaching hospital. Pet owners, ICU technicians. The introduction of the TPS, with live video streaming of patient images over the Internet, in a companion animal ICU. Pet owners experienced TPS as a valuable extra service. Most TPS users (72.4%) experienced less anxiety and felt less need (40.4% of TPS users) to visit their hospitalized pet in person. Most users (83.5%) shared TPS access with their family. The introduction of the TPS did not improve overall owner satisfaction, except for the score on "quality of medical treatment." Seven of 26 indicators of owner satisfaction were awarded higher scores by TPS users than by TPS nonusers in the survey after the introduction of the system. However, the lack of randomization of owners might have influenced findings. The enthusiasm of the ICU technicians for the system was tempered by the negative feedback from a small number of owners. Nevertheless they recognized the value of the system for owners. The system was user friendly and ICU staff and TPS users experienced few technical problems. As veterinary healthcare is moving toward a more client-centered approach, a virtual pet visit system, such as TPS, is a relatively simple application that may improve the well-being of most owners during the hospitalization of their pet. © Veterinary Emergency and Critical Care Society 2016.

Shuttle antenna radome technology test program. Volume 2: Development of S-band antenna interface design

NASA Technical Reports Server (NTRS)

Kuhlman, E. A.; Baranowski, L. C.

1977-01-01

The effects of the Thermal Protection Subsystem (TPS) contamination on the space shuttle orbiter S band quad antenna due to multiple mission buildup are discussed. A test fixture was designed, fabricated and exposed to ten cycles of simulated ground and flight environments. Radiation pattern and impedance tests were performed to measure the effects of the contaminates. The degradation in antenna performance was attributed to the silicone waterproofing in the TPS tiles rather than exposure to the contaminating sources used in the test program. Validation of the accuracy of an analytical thermal model is discussed. Thermal vacuum tests with a test fixture and a representative S band quad antenna were conducted to evaluate the predictions of the analytical thermal model for two orbital heating conditions and entry from each orbit. The results show that the accuracy of predicting the test fixture thermal responses is largely dependent on the ability to define the boundary and ambient conditions. When the test conditions were accurately included in the analytical model, the predictions were in excellent agreement with measurements.

Biodegradation Behaviour of Thermoplastic Starch Films Derived from Tacca leontopetaloides Starch under Controlled Composting Condition

NASA Astrophysics Data System (ADS)

Amin, A. M. Mohd; Sauid, S. Mohd; Hamid, K. H. Ku; Musa, M.

2018-05-01

The biodegradation study of thermoplastic starch (TPS) films derived from Tacca leontopetaloides starch; namely TPS/GLY, TPS/ACE and TPS/BCHR were investigated under controlled composting conditions. A manual set-up test rig in laboratory scale was built according to ISO 14855-1: 2012. The biodegradation percentage was determined by measuring the amount of CO2 evolved using titration method and validated by automatic system (Arduino UNO System) that detected the CO2 evolved. After 45 days under controlled composting condition, results indicated that TPS/GLY degraded the fastest, followed by TPS/BCHR and the TPS/ACE had the slowest degradation. The biodegradation process of TPS/GLY, TPS/ACE and TPS/BCHR also exhibited two stages with different degradation speeds. From these results, it indicated that chemical modification of the TPS films by adding acetic acid and rice husk bio-char to the thermoplastic starch can have a major impact on the biodegradation rate and final biodegradation percentage.

Thermal Protection System of the Space Shuttle

NASA Technical Reports Server (NTRS)

Cleland, John; Iannetti, Francesco

1989-01-01

The Thermal Protection System (TPS), introduced by NASA, continues to incorporate many of the advances in materials over the past two decades. A comprehensive, single-volume summary of the TPS, including system design rationales, key design features, and broad descriptions of the subsystems of TPS (E.g., reusable surface insulation, leading edge structural, and penetration subsystems) is provided. Details of all elements of TPS development and application are covered (materials properties, manufacturing, modeling, testing, installation, and inspection). Disclosures and inventions are listed and potential commercial application of TPS-related technology is discussed.

Mechanical analysis of confectioning flaw of refractory alloy honeycomb sandwich structure

NASA Astrophysics Data System (ADS)

He, Xiaodong; Kong, Xianghao; Shi, Liping; Li, Mingwei

2009-03-01

Thermal protection system is one of the key technology of reusable launch vehicle (RLV). After C/C and ceramic-matrix composite used in space orbiter, one new-typed thermal protection systems (TPS)-ARMOR TPS is coming forth. ARMOR TPS is means adaptable, robust, metallic, operable, reusable TPS. The ARMOR TPS has many advantages, for example: fixing easily, longer life, good properties, short time of maintenance and service. The ARMOR TPS is one of important candidate structure of RLV. ARMOR thermal protection system in foreign countries for reusable launch vehicle is used instead of the traditional ceramic-matrix composite thermal protection system and C/C thermal protection system. Also the constituent feature of ARMOR thermal protection system is much better than the traditional TPS. In comparison with traditional TPS, the ARMOR TPS will be the best selection for all kinds of RLV. So the ARMOR thermal protection system will be used in aviation and spaceflight field more and more widely because of its much better performance. ARMOR TPS panel is above the whole ARMOR TPS, and the metal honeycomb sandwich structure is the surface of the ARMOR TPS panel. So the metal honeycomb sandwich structure plays an important role in the ARMOR TPS, while it bears the flight dynamic pressure and stands against the flight dynamic calefaction. The metal honeycomb sandwich structure is made using the technique of the whole braze welding. In the course of the vacuum high temperature braze welding, its surface will appear concave. The reasons which lead to the shortage are summarized and discussed. The difference of thermal expansion coefficient and pressure between the core and the panels may be the chief reasons. This paper will analyze the mechanics behavior of metal honeycomb sandwich structure in the course of the vacuum high temperature braze welding, then make sure the reasons and get a way to solve it. Haynes214 is a good material of face sheet at present. γ - TiAl and microlaminate materials are the candidate materials in the future.

Thermal Protection System (Heat Shield) Development - Advanced Development Project

NASA Technical Reports Server (NTRS)

Kowal, T. John

2010-01-01

The Orion Thermal Protection System (TPS) ADP was a 3 1/2 year effort to develop ablative TPS materials for the Orion crew capsule. The ADP was motivated by the lack of available ablative TPS's. The TPS ADP pursued a competitive phased development strategy with succeeding rounds of development, testing and down selections. The Project raised the technology readiness level (TRL) of 8 different TPS materials from 5 different commercial vendors, eventual down selecting to a single material system for the Orion heat shield. In addition to providing a heat shield material and design for Orion on time and on budget, the Project accomplished the following: 1) Re-invigorated TPS industry & re-established a NASA competency to respond to future TPS needs; 2) Identified a potentially catastrophic problem with the planned MSL heat shield, and provided a viable, high TRL alternate heat shield design option; and 3) Transferred mature heat shield material and design options to the commercial space industry, including TPS technology information for the SpaceX Dragon capsule.

A design assessment of multiwall, metallic stand-off, and RSI reusable thermal protection systems including space shuttle application

NASA Technical Reports Server (NTRS)

Jackson, L. R.; Dixon, S. C.

1980-01-01

The design and assessment of reusable surface insulation (RSI), metallic stand off and multiwall thermal protection systems (TPS) is discussed. Multiwall TPS is described in some detail, and analyses useful for design of multiwall are included. Results indicate that multiwall has the potential to satisfy the TPS design goals better than the other systems. The total mass of the stand-off TPS and of the metallic systems require less primary structure mass than the RSI system, since the nonbuckling skin criteria required for RSI may be removed. Continued development of multiwall TPS is required to verify its potential and to provide the necessary data base for design.

Thermal protection systems manned spacecraft flight experience

NASA Technical Reports Server (NTRS)

Curry, Donald M.

1992-01-01

Since the first U.S. manned entry, Mercury (May 5, 1961), seventy-five manned entries have been made resulting in significant progress in the understanding and development of Thermal Protection Systems (TPS) for manned rated spacecraft. The TPS materials and systems installed on these spacecraft are compared. The first three vehicles (Mercury, Gemini, Apollo) used ablative (single-use) systems while the Space Shuttle Orbiter TPS is a multimission system. A TPS figure of merit, unit weight lb/sq ft, illustrates the advances in TPS material performance from Mercury (10.2 lb/sq ft) to the Space Shuttle (1.7 lb/sq ft). Significant advances have been made in the design, fabrication, and certification of TPS on manned entry vehicles (Mercury through Shuttle Orbiter). Shuttle experience has identified some key design and operational issues. State-of-the-art ceramic insulation materials developed in the 1970's for the Space Shuttle Orbiter have been used in the initial designs of aerobrakes. This TPS material experience has identified the need to develop a technology base from which a new class of higher temperature materials will emerge for advanced space transportation vehicles.

No Magic Bullet: A Theory-Based Meta-Analysis of Markov Transition Probabilities in Studies of Service Systems for Persons With Mental Disabilities.

PubMed

Leff, Hugh Stephen; Chow, Clifton M; Graves, Stephen C

2017-03-01

A random-effects meta-analysis of studies that used Markov transition probabilities (TPs) to describe outcomes for mental health service systems of differing quality for persons with serious mental illness was implemented to improve the scientific understanding of systems performance, to use in planning simulations to project service system costs and outcomes over time, and to test a theory of how outcomes for systems varying in quality differ. Nineteen systems described in 12 studies were coded as basic (B), maintenance (M), and recovery oriented (R) on the basis of descriptions of services provided. TPs for studies were aligned with a common functional-level framework, converted to a one-month time period, synthesized, and compared with theory-based expectations. Meta-regression was employed to explore associations between TPs and characteristics of service recipients and studies. R systems performed better than M and B systems. However, M systems did not perform better than B systems. All systems showed negative as well as positive TPs. For approximately one-third of synthesized TPs, substantial interstudy heterogeneity was noted. Associations were found between TPs and service recipient and study variables Conclusions: Conceptualizing systems as B, M, and R has potential for improving scientific understanding and systems planning. R systems appear more effective than B and M systems, although there is no "magic bullet" system for all service recipients. Interstudy heterogeneity indicates need for common approaches to reporting service recipient states, time periods for TPs, service recipient attributes, and service system characteristics. TPs found should be used in Markov simulations to project system effectiveness and costs of over time.

Masking properties of ceramics for veneer restorations.

PubMed

Skyllouriotis, Andreas L; Yamamoto, Hideo L; Nathanson, Dan

2017-10-01

The translucency and opacity of ceramics play a significant role in emulating the natural color of teeth, but studies of the masking properties and limitations of dental ceramics when used as monolayer restorations are lacking. The purpose of this in vitro study was to determine the translucency of 6 materials used for veneer restorations by assessing their translucency parameters (TPs), contrast ratios (CRs), and potential to mask dark tooth colors. Ten square- or disk-shaped specimens (0.5-mm thickness, shade A2) were fabricated from Vitablocks Mark II (VMII; Vita Zahnfabrik), IPS e.max CAD LT (EMXC LT; Ivoclar Vivadent AG), IPS e.max CAD HT (EMXC HT; Ivoclar Vivadent AG), IPS Empress CAD LT (EMP LT; Ivoclar Vivadent AG), IPS e.max Press LT (EMXP LT; Ivoclar Vivadent AG), and CZR (CZR; Kuraray Noritake Dental Inc). Their luminance (Y) values over black and over white tiles were measured, followed by their color (CIELab) over black tiles and white tiles and shaded A2 (control group), A3.5, A4, and B4 acrylic resin blocks. All measurements were performed using a spectrophotometer in 2 different areas on each specimen. Then CRs, TPs, and color differences (over shaded backgrounds) were determined. Data were subjected to 1-way and 2-way ANOVA (α=.05) for analysis. Mean CR values of EMXP LT were significantly higher than those of the other tested materials, whereas VMII and EMXC HT had the lowest values (P<.001). Mean TP values over black and over white backgrounds of VMII and EMXC HT were significantly higher than those of the other tested materials, while EMXP LT and EMXC LT revealed the lowest values (P<.001). Background shade A4 displayed the highest mean effect (expressed in ΔE* values) on the color of the ceramic materials, whereas shade B4 demonstrated the lowest mean background effect (P<.001). Significant differences in translucency among the tested ceramics were revealed (P<.001). The EMXC LT and EMXP LT groups were the least translucent under the conditions of this study (P<.001). All tested ceramics exhibited poor masking properties against the A4 background. The color differences of most tested ceramics were more acceptable when tested against the B4 background (ΔE*≤3.3). Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Two-Partner Secretion: Combining Efficiency and Simplicity in the Secretion of Large Proteins for Bacteria-Host and Bacteria-Bacteria Interactions

PubMed Central

Guérin, Jeremy; Bigot, Sarah; Schneider, Robert; Buchanan, Susan K.; Jacob-Dubuisson, Françoise

2017-01-01

Initially identified in pathogenic Gram-negative bacteria, the two-partner secretion (TPS) pathway, also known as Type Vb secretion, mediates the translocation across the outer membrane of large effector proteins involved in interactions between these pathogens and their hosts. More recently, distinct TPS systems have been shown to secrete toxic effector domains that participate in inter-bacterial competition or cooperation. The effects of these systems are based on kin vs. non-kin molecular recognition mediated by specific immunity proteins. With these new toxin-antitoxin systems, the range of TPS effector functions has thus been extended from cytolysis, adhesion, and iron acquisition, to genome maintenance, inter-bacterial killing and inter-bacterial signaling. Basically, a TPS system is made up of two proteins, the secreted TpsA effector protein and its TpsB partner transporter, with possible additional factors such as immunity proteins for protection against cognate toxic effectors. Structural studies have indicated that TpsA proteins mainly form elongated β helices that may be followed by specific functional domains. TpsB proteins belong to the Omp85 superfamily. Open questions remain on the mechanism of protein secretion in the absence of ATP or an electrochemical gradient across the outer membrane. The remarkable dynamics of the TpsB transporters and the progressive folding of their TpsA partners at the bacterial surface in the course of translocation are thought to be key elements driving the secretion process. PMID:28536673

A Risk-Based Approach for Aerothermal/TPS Analysis and Testing

DTIC Science & Technology

2007-07-01

RTO-EN-AVT-142 17 - 1 A Risk-Based Approach for Aerothermal/ TPS Analysis and Testing Michael J. Wright∗ and Jay H. Grinstead† NASA Ames...of the thermal protection system ( TPS ) is to protect the payload (crew, cargo, or science) from this entry heating environment. The performance of...the TPS is determined by the efficiency and reliability of this system, typically measured

An assessment of the impact of transition on advanced winged entry vehicle thermal protection system mass

NASA Technical Reports Server (NTRS)

Wurster, K. E.

1981-01-01

This study examines the impact of turbulent heating on thermal protection system (TPS) mass for advanced winged entry vehicles. Four basic systems are considered: insulative, metallic hot structures, metallic standoff, and hybrid systems. TPS sizings are performed using entry trajectories tailored specifically to the characteristics of each TPS concept under consideration. Comparisons are made between systems previously sized under the assumption of all laminar heating and those sized using a baseline estimate of transition and turbulent heating. The relative effect of different transition criteria on TPS mass requirements is also examined. Also investigated are entry trajectories tailored to alleviate turbulent heating. Results indicate the significant impact of turbulent heating on TPS mass and demonstrate the importance of both accurate transition criteria and entry trajectory tailoring.

KSC-04pd1851

NASA Image and Video Library

2004-09-18

KENNEDY SPACE CENTER, FLA. - Looking at damage inside the hurricane-ravaged Thermal Protection System Facility are KSC Director of Spaceport Services Scott Kerr (left) and NASA Associate Administrator of Space Operations Mission Directorate William Readdy (right). The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof during Hurricane Frances, which blew across Central Florida Sept. 4-5. Readdy and NASA Administrator Sean O’Keefe are visiting KSC to survey the damage sustained by KSC facilities from the hurricane. The Labor Day storm also caused significant damage to the Vehicle Assembly Building and Processing Control Center. Additionally, the Operations and Checkout Building, Vertical Processing Facility, Hangar AE, Hangar S and Hangar AF Small Parts Facility each received substantial damage. However, well-protected and unharmed were NASA’s three Space Shuttle orbiters - Discovery, Atlantis and Endeavour - along with the Shuttle launch pads, all of the critical flight hardware for the orbiters and the International Space Station, and NASA’s Swift spacecraft that is awaiting launch in October.

KSC-07pd2195

NASA Image and Video Library

2007-08-03

KENNEDY SPACE CENTER, FLA. - The STS-120 crew is at Kennedy for a crew equipment interface test, or CEIT. Inspecting the thermal protection system, or TPS, tiles on space shuttle Discovery in Orbiter Processing Facility bay 3 are Mission Specialists Douglas H. Wheelock and Paolo A. Nespoli, a European Space Agency astronaut from Italy, and Expedition 16 Flight Engineer Daniel M. Tani (with camera). Among the activities standard to a CEIT are harness training, inspection of the thermal protection system and camera operation for planned extravehicular activities, or EVAs. The STS-120 mission will deliver the Harmony module, christened after a school contest, which will provide attachment points for European and Japanese laboratory modules on the International Space Station. Known in technical circles as Node 2, it is similar to the six-sided Unity module that links the U.S. and Russian sections of the station. Built in Italy for the United States, Harmony will be the first new U.S. pressurized component to be added. The STS-120 mission is targeted to launch on Oct. 20. Photo credit: NASA/George Shelton

The relative effects of entry parameters on thermal protection system weight. [space shuttle orbiters

NASA Technical Reports Server (NTRS)

Hirasaki, P. N.

1971-01-01

Shielding a spacecraft from the severe thermal environment of an atmospheric entry requires a sophisticated thermal protection system (TPS). Thermal computer program models were developed for two such TPS designs proposed for the space shuttle orbiter. The multilayer systems, a reusable surface insulation TPS, and a re-radiative metallic skin TPS, were sized for a cross-section of trajectories in the entry corridor. This analysis indicates the relative influence of the entry parameters on the weight of each TPS concept. The results are summarized graphically. The trajectory variables considered were down-range, cross-range, orbit inclination, entry interface velocity and flight path angle, maximum heating rate level, angle of attack, and ballistic coefficient. Variations in cross-range and flight path angle over the ranges considered had virtually no effect on the required entry TPS weight. The TPS weight was significantly more sensitive to variations in angle of attack than to dispersions in the other trajectory considered.

The TPS Advanced Development Project for CEV

NASA Technical Reports Server (NTRS)

Reuther, James; Wercinski, Paul; Venkatapathy, Ethiraj; Ellerby, Don; Raiche, George; Bowman, Lynn; Jones, Craig; Kowal, John

2006-01-01

The CEV TPS Advanced Development Project (ADP) is a NASA in-house activity for providing two heatshield preliminary designs (a Lunar direct return as well as a LEO only return) for the CEV, including the TPS, the carrier structure, the interfaces and the attachments. The project s primary objective is the development of a single heatshield preliminary design that meets both Lunar direct return and LEO return requirements. The effort to develop the Lunar direct return capable heatshield is considered a high risk item for the NASA CEV development effort due to the low TRL (approx. 4) of the candidate TPS materials. By initiating the TPS ADP early in the development cycle, the intent is to use materials analysis and testing in combination with manufacturing demonstrations to reduce the programmatic risk of using advanced TPS technologies in the critical path for CEV. Due to the technical and schedule risks associated a Lunar return heatshield, the ADP will pursue a parallel path design approach, whereby a back-up TPS/heatshield design that only meets LEO return requirements is also developed. The TPS materials and carrier structure design concept selections will be based on testing, analysis, design and evaluation of scalability and manufacturing performed under the ADP. At the TPS PDR, the preferred programmatic strategy is to transfer the continued (detailed) design, development, testing and evaluation (DDT&E) of both the Lunar direct and LEO return designs to a government/prime contractor coordinated sub-system design team. The CEV prime contractor would have responsibility for the continued heatshield sub-system development. Continued government participation would include analysis, testing and evaluation as well as decision authority at TPS Final System Decision (FSD) (choosing between the primary and back-up heatshields) occurring between TPS PDR and TPS Critical Design Review (CDR). After TPS FSD the prime CEV contractor will complete the detailed design, certification testing, procurement, and integration of the CEV TPS.

Inspection of the Math Model Tools for On-Orbit Assessment of Impact Damage Report

NASA Technical Reports Server (NTRS)

Harris, Charles E.; Raju, Ivatury S.; Piascik, Robert S> ; KramerWhite, Julie A.; KramerWhite, Julie A.; Labbe, Steve G.; Rotter, Hank A.

2007-01-01

In Spring of 2005, the NASA Engineering Safety Center (NESC) was engaged by the Space Shuttle Program (SSP) to peer review the suite of analytical tools being developed to support the determination of impact and damage tolerance of the Orbiter Thermal Protection Systems (TPS). The NESC formed an independent review team with the core disciplines of materials, flight sciences, structures, mechanical analysis and thermal analysis. The Math Model Tools reviewed included damage prediction and stress analysis, aeroheating analysis, and thermal analysis tools. Some tools are physics-based and other tools are empirically-derived. Each tool was created for a specific use and timeframe, including certification, real-time pre-launch assessments. In addition, the tools are used together in an integrated strategy for assessing the ramifications of impact damage to tile and RCC. The NESC teams conducted a peer review of the engineering data package for each Math Model Tool. This report contains the summary of the team observations and recommendations from these reviews.

Preliminary Thermal-Mechanical Sizing of Metallic TPS: Process Development and Sensitivity Studies

NASA Technical Reports Server (NTRS)

Poteet, Carl C.; Abu-Khajeel, Hasan; Hsu, Su-Yuen

2002-01-01

The purpose of this research was to perform sensitivity studies and develop a process to perform thermal and structural analysis and sizing of the latest Metallic Thermal Protection System (TPS) developed at NASA LaRC (Langley Research Center). Metallic TPS is a key technology for reducing the cost of reusable launch vehicles (RLV), offering the combination of increased durability and competitive weights when compared to other systems. Accurate sizing of metallic TPS requires combined thermal and structural analysis. Initial sensitivity studies were conducted using transient one-dimensional finite element thermal analysis to determine the influence of various TPS and analysis parameters on TPS weight. The thermal analysis model was then used in combination with static deflection and failure mode analysis of the sandwich panel outer surface of the TPS to obtain minimum weight TPS configurations at three vehicle stations on the windward centerline of a representative RLV. The coupled nature of the analysis requires an iterative analysis process, which will be described herein. Findings from the sensitivity analysis are reported, along with TPS designs at the three RLV vehicle stations considered.

Improvements in Thermal Protection Sizing Capabilities for TCAT: Conceptual Design for Advanced Space Transportation Systems

NASA Technical Reports Server (NTRS)

Olds, John R.; Izon, Stephen James

2002-01-01

The Thermal Calculation Analysis Tool (TCAT), originally developed for the Space Systems Design Lab at the Georgia Institute of Technology, is a conceptual design tool capable of integrating aeroheating analysis into conceptual reusable launch vehicle design. It provides Thermal Protection System (TPS) unit thicknesses and acreage percentages based on the geometry of the vehicle and a reference trajectory to be used in calculation of the total cost and weight of the vehicle design. TCAT has proven to be reasonably accurate at calculating the TPS unit weights for in-flight trajectories; however, it does not have the capability of sizing TPS materials above cryogenic fuel tanks for ground hold operations. During ground hold operations, the vehicle is held for a brief period (generally about two hours) during which heat transfer from the TPS materials to the cryogenic fuel occurs. If too much heat is extracted from the TPS material, the surface temperature may fall below the freezing point of water, thereby freezing any condensation that may be present at the surface of the TPS. Condensation or ice on the surface of the vehicle is potentially hazardous to the mission and can also damage the TPS. It is questionable whether or not the TPS thicknesses provided by the aeroheating analysis would be sufficiently thick to insulate the surface of the TPS from the heat transfer to the fuel. Therefore, a design tool has been developed that is capable of sizing TPS materials at these cryogenic fuel tank locations to augment TCAT's TPS sizing capabilities.

Impact of cabin environment on thermal protection system of crew hypersonic vehicle

NASA Astrophysics Data System (ADS)

Zhu, Xiao Wei; Zhao, Jing Quan; Zhu, Lei; Yu, Xi Kui

2016-05-01

Hypersonic crew vehicles need reliable thermal protection systems (TPS) to ensure their safety. Since there exists relative large temperature difference between cabin airflow and TPS structure, the TPS shield that covers the cabin is always subjected to a non-adiabatic inner boundary condition, which may influence the heat transfer characteristic of the TPS. However, previous literatures always neglected the influence of the inner boundary by assuming that it was perfectly adiabatic. The present work focuses on studying the impact of cabin environment on the thermal performance. A modified TPS model is created with a mixed thermal boundary condition to connect the cabin environment with the TPS. This helps make the simulation closer to the real situation. The results stress that cabin environment greatly influences the temperature profile inside the TPS, which should not be neglected in practice. Moreover, the TPS size can be optimized during the design procedure if taking the effect of cabin environment into account.

Flexible Thermal Protection System Development for Hypersonic Inflatable Aerodynamic Decelerators

NASA Technical Reports Server (NTRS)

DelCorso, Joseph A.; Bruce, Walter E., III; Hughes, Stephen J.; Dec, John A.; Rezin, Marc D.; Meador, Mary Ann B.; Guo, Haiquan; Fletcher, Douglas G.; Calomino, Anthony M.; Cheatwood, McNeil

2012-01-01

The Hypersonic Inflatable Aerodynamic Decelerators (HIAD) project has invested in development of multiple thermal protection system (TPS) candidates to be used in inflatable, high downmass, technology flight projects. Flexible TPS is one element of the HIAD project which is tasked with the research and development of the technology ranging from direct ground tests, modelling and simulation, characterization of TPS systems, manufacturing and handling, and standards and policy definition. The intent of flexible TPS is to enable large deployable aeroshell technologies, which increase the drag performance while significantly reducing the ballistic coefficient of high-mass entry vehicles. A HIAD requires a flexible TPS capable of surviving aerothermal loads, and durable enough to survive the rigors of construction, handling, high density packing, long duration exposure to extrinsic, in-situ environments, and deployment. This paper provides a comprehensive overview of key work being performed within the Flexible TPS element of the HIAD project. Included in this paper is an overview of, and results from, each Flexible TPS research and development activity, which includes ground testing, physics-based thermal modelling, age testing, margins policy, catalysis, materials characterization, and recent developments with new TPS materials.

Thermal Analysis of Thermal Protection System of Test Launch Vehicle

NASA Astrophysics Data System (ADS)

Kim, Jongmin

2017-10-01

In this paper, a thermal analysis of the thermal protection system (TPS) of test launch vehicle (TLV) is explained. TLV is heated during the flight due to engine exhaust plume gas by thermal radiation and a TPS is needed to protect the vehicle from the heating. The thermal analysis of the TPS is conducted to predict the heat flux from plume gas and temperature of the TPS during the flight. To simplify the thermal analysis, plume gas radiation and radiative properties are assumed to be surface radiation and constants, respectively. Thermal conductivity, emissivity and absorptivity of the TPS material are measured. Proper plume conditions are determined from the preliminary analysis and then the heat flux and temperature of the TPS are calculated.

Development of 3D Woven Ablative Thermal Protection Systems (TPS) for NASA Spacecraft

NASA Technical Reports Server (NTRS)

Feldman, Jay D.; Ellerby, Don; Stackpoole, Mairead; Peterson, Keith; Venkatapathy, Ethiraj

2015-01-01

The development of a new class of thermal protection system (TPS) materials known as 3D Woven TPS led by the Entry Systems and Technology Division of NASA Ames Research Center (ARC) will be discussed. This effort utilizes 3D weaving and resin infusion technologies to produce heat shield materials that are engineered and optimized for specific missions and requirements. A wide range of architectures and compositions have been produced and preliminarily tested to prove the viability and tailorability of the 3D weaving approach to TPS.

Development of Metallic Thermal Protection Systems for the Reusable Launch Vehicle

NASA Technical Reports Server (NTRS)

Blosser, Max L.

1996-01-01

A reusable Thermal Protection System (TPS) that is not only lightweight, but durable, operable and cost effective is one of the technologies required by the Reusable Launch Vehicle (RLV) to achieve the goal of drastically reducing the cost of delivering payload to orbit. Metallic TPS is one of the systems being developed to meet this challenge. Current efforts involve improving the superalloy honeycomb TPS concept, which consists of a foil-gage metallic box encapsulating a low density fibrous insulation, and evaluating it for RLV requirements. The superalloy honeycomb TPS concept is mechanically attached to the vehicle structure. Improvements include more efficient internal insulation, a simpler, lighter weight configuration, and a quick-release fastener system for easier installation and removal. Evaluation includes thermal and structural analysis, fabrication and testing of both coupons and TPS panels under conditions simulating RLV environments. Coupons of metallic honeycomb sandwich, representative of the outer TPS surface, were subjected to low speed impact, hypervelocity impact, and rain erosion testing as well as subsequent arcjet exposure. Arrays of TPS panels have been subjected to radiant heating in a thermal/vacuum facility, aerodynamic heating in an arcjet facility and acoustic loading.

Thermal protection system flight repair kit

NASA Technical Reports Server (NTRS)

1979-01-01

A thermal protection system (TPS) flight repair kit required for use on a flight of the Space Transportation System is defined. A means of making TPS repairs in orbit by the crew via extravehicular activity is discussed. A cure in place ablator, a precured ablator (large area application), and packaging design (containers for mixing and dispensing) for the TPS are investigated.

Utility of the Paris System in Reporting Urine Cytology.

PubMed

Malviya, Kiran; Fernandes, Gwendolyn; Naik, Leena; Kothari, Kanchan; Agnihotri, Mona

2017-01-01

To find out the utility of The Paris System (TPS) in reporting urine cytology and to compare it with the reporting system currently used in our laboratory. This retrospective study was undertaken over a period of 1 year during which slides of all the urine specimens sent for cytological examination were retrieved from our laboratory filling system. They were blindly reviewed and reclassified according to TPS. Surgical follow-up was obtained from the uropathology services of our department. A total of 176 cases were meticulously reviewed. The mean age of the patients was 52 years, and 71% of cases presented with hematuria. Histopathological follow-up was available in 34 cases. Reporting by TPS detected 13.0% high-grade urothelial carcinoma (HGUC) and 5.1% atypical urothelial cells versus 7.3 and 11.9% by the current reporting system, respectively. The sensitivity and diagnostic accuracy for detecting HGUC of TPS were higher than those of our reporting system. TPS has increased the rate of detection of HGUC and reduced the rate of reporting "atypical" urothelial cells. TPS has also standardized the diagnostic criteria, thereby bringing uniformity and reproducibility into the system of reporting for urine cytology. © 2017 S. Karger AG, Basel.

TPS Ablator Technologies for Interplanetary Spacecraft

NASA Technical Reports Server (NTRS)

Curry, Donald M.

2004-01-01

This slide presentation reviews the status of Thermal Protection System (TPS) Ablator technologies and the preparation for use in interplanetary spacecraft. NASA does not have adequate TPS ablatives and sufficient selection for planned missions. It includes a comparison of shuttle and interplanetary TPS requirements, the status of mainline TPS charring ablator materials, a summary of JSC SBIR accomplishments in developing advanced charring ablators and the benefits of SBIR Ablator/fabrication technology.

KSC-04pd1843

NASA Image and Video Library

2004-09-18

KENNEDY SPACE CENTER, FLA. - - NASA Administrator Sean O’Keefe (right) looks at equipment moved from the Thermal Protection System Facility to the RLV Hangar. At left are United Space Alliance technicians Shelly Kipp and Eric Moss. O’Keefe and NASA Associate Administrator of Space Operations Mission Directorate William Readdy are visiting KSC to survey the damage sustained by KSC facilities from Hurricane Frances. The Thermal Protection System Facility (TPSF), which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof in the storm, which blew across Central Florida Sept. 4-5. Undamaged equipment was removed from the TPSF and stored in the hangar. The Labor Day storm also caused significant damage to the Vehicle Assembly Building and Processing Control Center. Additionally, the Operations and Checkout Building, Vertical Processing Facility, Hangar AE, Hangar S and Hangar AF Small Parts Facility each received substantial damage. However, well-protected and unharmed were NASA’s three Space Shuttle orbiters - Discovery, Atlantis and Endeavour - along with the Shuttle launch pads, all of the critical flight hardware for the orbiters and the International Space Station, and NASA’s Swift spacecraft that is awaiting launch in October.

Carbon nanotubes in blends of polycaprolactone/thermoplastic starch.

PubMed

Taghizadeh, Ata; Favis, Basil D

2013-10-15

Despite the importance of polymer-polymer multiphase systems, very little work has been carried out on the preferred localization of solid inclusions in such multiphase systems. In this work, carbon nanotubes (CNT) are dispersed with polycaprolactone (PCL) and thermoplastic starch (TPS) at several CNT contents via a combined solution/twin-screw extrusion melt mixing method. A PCL/CNT masterbatch was first prepared and then blended with 20 wt% TPS. Transmission and scanning electron microscopy images reveal a CNT localization principally in the TPS phase and partly at the PCL/TPS interface, with no further change by annealing. This indicates a strong driving force for the CNTs toward TPS. Young's model predicts that the nanotubes should be located at the interface. X-ray photoelectron spectroscopy (XPS) of extracted CNTs quantitatively confirms an encapsulation by TPS and reveals a covalent bonding of CNTs with thermoplastic starch. It appears likely that the nanotubes migrate to the interface, react with TPS and then are subsequently drawn into the low viscosity TPS phase. In a low shear rate/low shear stress internal mixer the nanotubes are found both in the PCL phase and at the PCL/TPS interface and have not completed the transit to the TPS phase. This latter result indicates the importance of choosing appropriate processing conditions in order to minimize kinetic effects. The addition of CNTs to PCL results in an increase in the crystallization temperature and a decrease in the percent crystallinity confirming the heterogeneous nucleating effect of the nanotubes. Finally, DMA analysis reveals a dramatic decrease in the starch rich phase transition temperature (~26 °C), for the system with nanotubes located in the TPS phase. Copyright © 2013 Elsevier Ltd. All rights reserved.

Heat Shielding Characteristics and Thermostructural Performance of a Superalloy Honeycomb Sandwich Thermal Protection System (TPS)

NASA Technical Reports Server (NTRS)

Ko, William L.

2004-01-01

Heat-transfer, thermal bending, and mechanical buckling analyses have been performed on a superalloy "honeycomb" thermal protection system (TPS) for future hypersonic flight vehicles. The studies focus on the effect of honeycomb cell geometry on the TPS heat-shielding performance, honeycomb cell wall buckling characteristics, and the effect of boundary conditions on the TPS thermal bending behavior. The results of the study show that the heat-shielding performance of a TPS panel is very sensitive to change in honeycomb core depth, but insensitive to change in honeycomb cell cross-sectional shape. The thermal deformations and thermal stresses in the TPS panel are found to be very sensitive to the edge support conditions. Slight corrugation of the honeycomb cell walls can greatly increase their buckling strength.

An automated data management/analysis system for space shuttle orbiter tiles. [stress analysis

NASA Technical Reports Server (NTRS)

Giles, G. L.; Ballas, M.

1982-01-01

An engineering data management system was combined with a nonlinear stress analysis program to provide a capability for analyzing a large number of tiles on the space shuttle orbiter. Tile geometry data and all data necessary of define the tile loads environment accessed automatically as needed for the analysis of a particular tile or a set of tiles. User documentation provided includes: (1) description of computer programs and data files contained in the system; (2) definitions of all engineering data stored in the data base; (3) characteristics of the tile anaytical model; (4) instructions for preparation of user input; and (5) a sample problem to illustrate use of the system. Description of data, computer programs, and analytical models of the tile are sufficiently detailed to guide extension of the system to include additional zones of tiles and/or additional types of analyses

Image Science and Analysis Group Spacecraft Damage Detection/Characterization

NASA Technical Reports Server (NTRS)

Wheaton, Ira M., Jr.

2010-01-01

This project consisted of several tasks that could be served by an intern to assist the ISAG in detecting damage to spacecrafts during missions. First, this project focused on supporting the Micrometeoroid Orbital Debris (MMOD) damage detection and assessment for the Hubble Space Telescope (HST) using imagery from the last two HST Shuttle servicing missions. In this project, we used coordinates of two windows on the Shuttle Aft flight deck from where images were taken and the coordinates of three ID points in order to calculate the distance from each window to the three points. Then, using the specifications from the camera used, we calculated the image scale in pixels per inch for planes parallel to and planes in the z-direction to the image plane (shown in Table 1). This will help in the future for calculating measurements of objects in the images. Next, tabulation and statistical analysis were conducted for screening results (shown in Table 2) of imagery with Orion Thermal Protection System (TPS) damage. Using the Microsoft Excel CRITBINOM function and Goal Seek, the probabilities of detection of damage to different shuttle tiles were calculated as shown in Table 3. Using developed measuring tools, volume and area measurements will be created from 3D models of Orion TPS damage. Last, mathematical expertise was provided to the Photogrammetry Team. These mathematical tasks consisted of developing elegant image space error equations for observations along 3D lines, circles, planes, etc. and checking proofs for minimal sets of sufficient multi-linear constraints. Some of the processes and resulting equations are displayed in Figure 1.

MO-FG-202-05: Identifying Treatment Planning System Errors in IROC-H Phantom Irradiations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kerns, J; Followill, D; Howell, R

Purpose: Treatment Planning System (TPS) errors can affect large numbers of cancer patients receiving radiation therapy. Using an independent recalculation system, the Imaging and Radiation Oncology Core-Houston (IROC-H) can identify institutions that have not sufficiently modelled their linear accelerators in their TPS model. Methods: Linear accelerator point measurement data from IROC-H’s site visits was aggregated and analyzed from over 30 linear accelerator models. Dosimetrically similar models were combined to create “classes”. The class data was used to construct customized beam models in an independent treatment dose verification system (TVS). Approximately 200 head and neck phantom plans from 2012 to 2015more » were recalculated using this TVS. Comparison of plan accuracy was evaluated by comparing the measured dose to the institution’s TPS dose as well as the TVS dose. In cases where the TVS was more accurate than the institution by an average of >2%, the institution was identified as having a non-negligible TPS error. Results: Of the ∼200 recalculated plans, the average improvement using the TVS was ∼0.1%; i.e. the recalculation, on average, slightly outperformed the institution’s TPS. Of all the recalculated phantoms, 20% were identified as having a non-negligible TPS error. Fourteen plans failed current IROC-H criteria; the average TVS improvement of the failing plans was ∼3% and 57% were found to have non-negligible TPS errors. Conclusion: IROC-H has developed an independent recalculation system to identify institutions that have considerable TPS errors. A large number of institutions were found to have non-negligible TPS errors. Even institutions that passed IROC-H criteria could be identified as having a TPS error. Resolution of such errors would improve dose delivery for a large number of IROC-H phantoms and ultimately, patients.« less

TPS1 terminator increases mRNA and protein yield in a Saccharomyces cerevisiae expression system.

PubMed

Yamanishi, Mamoru; Katahira, Satoshi; Matsuyama, Takashi

2011-01-01

Both terminators and promoters regulate gene expression. In Saccharomyces cerevisiae, the TPS1 terminator (TPS1t), coupled to a gene encoding a fluorescent protein, produced more transgenic mRNA and protein than did similar constructs containing other terminators, such as CYC1t, TDH3t, and PGK1t. This suggests that TPS1t can be used as a general terminator in the development of metabolically engineered yeast in high-yield systems.

Aerothermal Test of Thermal Protection Systems for X-33 Reusable Launch Vehicle

NASA Technical Reports Server (NTRS)

Sawyer, James Wayne; Hodge, Jefferson; Moore, Brad; Snyder, Kevin

1999-01-01

An array of metallic Thermal Protection System (TPS) panels developed for the windward surface of the X-33 vehicle was tested in the 8-Foot High Temperature Tunnel at the NASA Langley Research Center. These tests were the first aerothermal tests of an X-33 TPS array and the test results will be used to validate the TPS for the X-33 flight program. Specifically, the tests evaluated the structural and thermal performance of the TPS, the effectiveness of the high temperature seals between adjacent panels and the durability of the TPS under realistic aerothermal flight conditions. The effect of varying panel-to-panel step heights, intentional damage to the seals between adjacent panels, and the use of secondary seals were also investigated during the test program. The metallic TPS developed for the windward surface of the X-33, the blanket TPS developed to protect the leeward surfaces of the X-33, and the test program in the 8-Foot High Temperature Tunnel are presented and discussed.

STS-134 crew during EVA TPS Overview training in the TPS/PABF

NASA Image and Video Library

2009-12-15

JSC2009-E-284901 (15 Dec. 2009) --- NASA astronauts Gregory H. Johnson (left), STS-134 pilot; and Michael Fincke, mission specialist, participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA?s Johnson Space Center.

Orbiter thermal protection system

NASA Technical Reports Server (NTRS)

Dotts, R. L.; Curry, D. M.; Tillian, D. J.

1985-01-01

The major material and design challenges associated with the orbiter thermal protection system (TPS), the various TPS materials that are used, the different design approaches associated with each of the materials, and the performance during the flight test program are described. The first five flights of the Orbiter Columbia and the initial flight of the Orbiter Challenger provided the data necessary to verify the TPS thermal performance, structural integrity, and reusability. The flight performance characteristics of each TPS material are discussed, based on postflight inspections and postflight interpretation of the flight instrumentation data. Flights to date indicate that the thermal and structural design requirements for the orbiter TPS are met and that the overall performance is outstanding.

Mechanical attachments for flexible blanket TPS

NASA Astrophysics Data System (ADS)

Newquist, Charles W.; Anderson, David M.; Shorey, Mark W.; Preedy, Kristina S.

1998-01-01

The operability of a flexible blanket thermal protection system for a reusable launch vehicle can be improved by using mechanical attachments instead of adhesive bonding to fasten the thermal protection system to the vehicle structure. Mechanical attachments offer specific benefits by (1) permitting the use of composite or metal structures at or near their maximum temperatures (above the adhesive temperature limit) thereby reducing the required TPS thickness and weight, (2) significantly reducing both the frequency and time for TPS replacement, (3) providing easy access to hatches and the underlying structure, and (4) allowing the attachment of flexible TPS to integral cryotanks, where the TPS/structure interface temperature may fall below the lower temperature of the silicone adhesives.

FTIR instrumentation to monitor vapors from Shuttle tile waterproofing materials

NASA Technical Reports Server (NTRS)

Mattson, C. B.; Schwindt, C. J.

1995-01-01

The Space Shuttle Thermal Protection System (TPS) tiles and blankets are waterproofed using DimethylEthoxySilane (DMEX) in the Orbiter Processing Facilities (OPF). DMES has a Threshold Limit Value (TLV) for exposure of personnel to vapor concentration in air of 0.5 ppm. The OPF high bay cannot be opened for normal work after a waterproofing operation until the DMES concentration is verified by measurement to be below the TLV. On several occasions the high bay has been kept closed for up to 8 hours following waterproofing operations due to high DMES measurements. In addition, the Miran 203 and Miran 1 BX infrared analyzers calibrated at different wavelengths gave different readings under the same conditions. There was reason to believe that some of the high DMES concentration readings were caused by interference form water and ethanol vapors. The Toxic Vapor Detection Laboratory (TVDL) was asked to test the existing DMES instruments and identify the best qualified instrument. In addition the TVDL was requested to develop instrumentation to ensure the OPF high bay could be opened safely as soon as possible after a waterproofing operation. A Fourier Transform Infrared (FTIR) spectrophotometer instrument developed for an earlier project was reprogrammed to measure DMES vapor along with ethanol, water, and several common solvent vapors. The FTIR was then used to perform a series of laboratory and field tests to evaluate the performance of the single wavelength IR instruments in use. The results demonstrated that the single wavelength IR instruments did respond to ethanol and water vapors, more or less depending on the analytical IR wavelength selected. The FTIR was able to separate the responses to DMES, water and ethanol, and give consistent readings for the DMES vapor concentration. The FTIR was then deployed to the OPF to monitor real waterproofing operations. The FTIR was also used to measure the time for DMES to evaporate from TPS tile under a range of humidity conditions in controlled laboratory tests. The combination of laboratory and field tests with the FTIR instrument demonstrated superior sensitivity, ability to reject interference from water and ethanol vapors, ruggedness to be transported from the lab to the OPF and set up without special procedures or degradation of performance. The multiple component vapor analysis algorithm was developed at KSC and incorporates automatic baseline correction and shape fitting of the spectra. The analysis for DMES, TetraMethylDiSiloxane (TMDS), ethanol, methanol, isopropanol, and baseline parameters uses 161 points per sample at 4 cm(exp -1) resolution, and processes an eight scan sample every ten seconds. The standard deviation of the measurements is 0.013 ppm and the upper linear limit is 125 ppm DMES. Based on successful demonstration of capabilities we produced three mobile instrument carts to be used in each OPF to support future waterproofing operations. The design and building of the 'DMES Carts' were accomplished in Fiscal year 1995.

Direct atomic force microscopy observation of DNA tile crystal growth at the single-molecule level.

PubMed

Evans, Constantine G; Hariadi, Rizal F; Winfree, Erik

2012-06-27

While the theoretical implications of models of DNA tile self-assembly have been extensively researched and such models have been used to design DNA tile systems for use in experiments, there has been little research testing the fundamental assumptions of those models. In this paper, we use direct observation of individual tile attachments and detachments of two DNA tile systems on a mica surface imaged with an atomic force microscope (AFM) to compile statistics of tile attachments and detachments. We show that these statistics fit the widely used kinetic Tile Assembly Model and demonstrate AFM movies as a viable technique for directly investigating DNA tile systems during growth rather than after assembly.

Self-diagnostic thermal protection systems for future spacecraft

NASA Astrophysics Data System (ADS)

Hanlon, Alaina B.

The thermal protection system (TPS) represents the greatest risk factor after propulsion for any transatmospheric mission (Dr. Charles Smith, NASA ARC). Any damage to the TPS leaves the space vehicle vulnerable and could result in the loss of human life as happened in the Columbia accident. Aboard the current Space Shuttle Orbiters no system exists to notify the astronauts or ground control if the thermal protection system has been damaged. Through this research, a proof-of-concept monitoring system was developed. The system has two specific applications for thermal protection systems: (1) Improving models used to predict thermal and mechanical response of TPS materials, and (2) Self-diagnosing damage within regions of the TPS and communicating the damage to the appropriate personnel over a potentially unstable network. Mechanical damage is among the most important things to protect the TPS against. Methods to detect the primary types of mechanical damage suffered by thermal protection systems have been developed. Lightweight, low-power sensors were developed to detect any cracks in small regions of a TPS. Implementation of a network of these sensors within 10's to 1000's of regions will eventually provide high spatial resolution of damage detection; allowing for detection of holes in the TPS. Also important in thermal protection material development is to know the ablation rates and time/temperature response of the materials. A new type of sensor has been developed to monitor temperature at different depths within thermal protection materials. The signals being transmitted through the sensors can be multiplexed to allow for mechanical damage and temperature to be monitored using the same sensor.

Review of Lean Construction Conference Proceedings and Relationship to the Toyota Production System Framework

ERIC Educational Resources Information Center

Jacobs, Gideon Francois

2010-01-01

The objective of this study was to align the International Group of Lean Construction (IGLC) conference proceedings against the Toyota Production System (TPS) to determine how well research themes in construction studies align with the TPS framework. Factories around the world that have implemented the TPS framework have experienced impressive…

Randomized multicenter comparison of 2 IMZ and 4 TPS screw implants supporting bar-retained overdentures in 425 edentulous mandibles.

PubMed

Mau, Jochen; Behneke, Alexandra; Behneke, Nikolaus; Fritzemeier, Claus Udo; Gomez-Roman, German; d'Hoedt, Bernd; Spiekermann, Hubertus; Strunz, Volker; Yong, Mei

2003-01-01

Two treatment concepts for implant-supported bar retention of mandibular overdentures-2 intramobile cylinder (IMZ) implants and a Dolder bar and 4 titanium plasma-sprayed (TPS) screw implants and an angulated bar-were compared in a randomized controlled clinical trial with respect to postprosthetic efficacy and safety. Four hundred twenty-five patients with edentulous mandibles were enrolled; 212 were randomized to TPS implants (control group) and 213 to IMZ implants (test group). Endpoints were occurrences of postprosthetic integration deficiency (ID), functional deficiency (FD), and complications. The trial was sized to detect a 10% difference in 5-year ID-free postprosthetic system lifetime with a power of 80%. With 340 protocol-completed cases, the trial achieved its predetermined power. The 2 systems did not show statistically significant differences in occurrences of postprosthetic ID and FD; 5-year occurrence-free postprosthetic system lifetime probabilities were estimated as 42.5% with IMZ and 42.8% with TPS, for ID; and as 82.6% with IMZ and 87.2% with TPS, for FD. However, at 3 to 6 months after surgery, mean Periotest values were significantly higher (P = .0001 without adjustment) with IMZ implants (5.6, SD 4.2) than with TPS implants (0.8, SD 4.3). TPS implants showed a higher incidence of inflammation and recession, while IMZ implants had a higher incidence of implant fracture after functional loading. The system-wise approach overcomes potential bias with implant-wise analyses. A combination of radiographic and clinical criteria distinguishes between desirable integration and functional anchorage. The in situ survival rates at 5 years in this study (95% for IMZ, 92% for TPS) match rates reported in the literature. This study demonstrated equivalent efficacy of 2 IMZ cylinders and 4 TPS screws in implant-supported, bar-retained mandibular overdentures and indicated a higher rate of complications with the TPS screw implants.

STS-134 crew during EVA TPS Overview training in the TPS/PABF

NASA Image and Video Library

2009-12-15

JSC2009-E-284896 (15 Dec. 2009) --- NASA astronauts Gregory H. Johnson (left), STS-134 pilot; along with astronauts Michael Fincke (center) and Greg Chamitoff, both mission specialists, participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA?s Johnson Space Center.

STS-134 crew during EVA TPS Overview training in the TPS/PABF

NASA Image and Video Library

2009-12-15

JSC2009-E-284893 (15 Dec. 2009) --- NASA astronaut Gregory H. Johnson (right), STS-134 pilot; and European Space Agency astronaut Roberto Vittori, mission specialist, participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA?s Johnson Space Center.

Transient aero-thermal mapping of passive Thermal Protection system for nose-cap of Reusable Hypersonic Vehicle

NASA Astrophysics Data System (ADS)

Mahulikar, Shripad P.; Khurana, Shashank; Dungarwal, Ritesh; Shevakari, Sushil G.; Subramanian, Jayakumar; Gujarathi, Amit V.

2008-12-01

The temperature field history of passive Thermal Protection System (TPS) material at the nose-cap (forward stagnation region) of a Reusable Hypersonic Vehicle (RHV) is generated. The 3-D unsteady heat transfer model couples conduction in the solid with external convection and radiation that are modeled as time-varying boundary conditions on the surface. Results are presented for the following two cases: (1) nose-cap comprised of ablative TPS material only (SIRCA/PICA), and (2) nose-cap comprised of a combination of ablative TPS material with moderate thermal conductivity and insulative TPS material. Comparison of the temperature fields of SIRCA and PICA [Case (1)] indicates lowering of the peak stagnation region temperatures for PICA, due to its higher thermal conductivity. Also, the use of PICA and insulative TPS [Case (2)] for the nose-cap has higher potential for weight reduction than the use of ablative TPS alone.

Comparison of thermophilic anaerobic digestion characteristics between single-phase and two-phase systems for kitchen garbage treatment.

PubMed

Park, YongJin; Hong, Feng; Cheon, JiHoon; Hidaka, Taira; Tsuno, Hiroshi

2008-01-01

Lab-scale single-phase and two-phase thermophilic methane fermentation systems (SPS and TPS, respectively) were operated and fed with artificial kitchen waste. In both SPS and TPS, the highest methane recovery ratio of 90%, in terms of chemical oxygen demand by dichromate (CODcr), was observed at an organic loading rate (OLR) of 15 gCODcr/(l.d). The ratio of particle CODcr remaining to total CODcr in the influent was 0.1 and the ratio of NH(4)-N concentration to the input total nitrogen concentration was 0.5 in both SPS and TPS. However, the propionate concentration in the SPS reactor fluctuated largely and was 2 gCODcr/l higher than that in TPS, indicating less stable digestion. Regardless, efficient kitchen waste degradation can be accomplished in both SPS and TPS at an OLR of <20 gCODcr/(l.d), even though TPS may be more stable and easier to maintain. Bacillus coagulans predominated with an occupied ratio of approximately 90% in the acid fermentation reactor of TPS, and then a richer microbial community with a higher Shannon index value was maintained in the methane fermentation reactor of TPS than in the SPS reactor.

SU-F-T-667: Development and Validation of Dose Calculation for An Open-Source KV Treatment Planning System for Small Animal Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prajapati, S; Mo, X; Bednarz, B

Purpose: An open-source, convolution/superposition based kV-treatment planning system(TPS) was developed for small animal radiotherapy from previously existed in-house MV-TPS. It is flexible and applicable to both step and shoot and helical tomotherapy treatment delivery. For initial commissioning process, the dose calculation from kV-TPS was compared with measurements and Monte Carlo(MC) simulations. Methods: High resolution, low energy kernels were simulated using EGSnrc user code EDKnrc, which was used as an input in kV-TPS together with MC-simulated x-ray beam spectrum. The Blue Water™ homogeneous phantom (with film inserts) and heterogeneous phantom (with film and TLD inserts) were fabricated. Phantom was placed atmore » 100cm SSD, and was irradiated with 250 kVp beam for 10mins with 1.1cm × 1.1cm open field (at 100cm) created by newly designed binary micro-MLC assembly positioned at 90cm SSD. Gafchromic™ EBT3 film was calibrated in-phantom following AAPM TG-61 guidelines, and were used for measurement at 5 different depths in phantom. Calibrated TLD-100s were obtained from ADCL. EGS and MNCP5 simulation were used to model experimental irradiation set up calculation of dose in phantom. Results: Using the homogeneous phantom, dose difference between film and kV-TPS was calculated: mean(x)=0.9%; maximum difference(MD)=3.1%; standard deviation(σ)=1.1%. Dose difference between MCNP5 and kV-TPS was: x=1.5%; MD=4.6%; σ=1.9%. Dose difference between EGS and kV-TPS was: x=0.8%; MD=1.9%; σ=0.8%. Using the heterogeneous phantom, dose difference between film and kV-TPS was: x=2.6%; MD=3%; σ=1.1%; and dose difference between TLD and kV-TPS was: x=2.9%; MD=6.4%; σ=2.5%. Conclusion: The inhouse, open-source kV-TPS dose calculation system was comparable within 5% of measurements and MC simulations in both homogeneous and heterogeneous phantoms. The dose calculation system of the kV-TPS is validated as a part of initial commissioning process for small animal radiotherapy. The kV-TPS has the potential for accurate dose calculation for any kV treatment or imaging modalities.« less

Verification tests of durable TPS concepts

NASA Technical Reports Server (NTRS)

Shideler, J. L.; Webb, G. L.; Pittman, C. M.

1984-01-01

Titanium multiwall, superalloy honeycomb, and Advanced Carbon-carbon (ACC) multipost Thermal Protection System (TPS) concepts are being developed to provide durable protection for surfaces of future space transportation systems. Verification tests including thermal, vibration, acoustic, water absorption, lightning strike, and aerothermal tests are described. Preliminary results indicate that the three TPS concepts are viable up to a surface temperature in excess of 2300 F.

STS-134 crew during EVA TPS Overview training in the TPS/PABF

NASA Image and Video Library

2009-12-15

JSC2009-E-284898 (15 Dec. 2009) --- NASA astronauts Gregory H. Johnson (center), STS-134 pilot; and Michael Fincke (right), mission specialist; along with European Space Agency astronaut Roberto Vittori, mission specialist, participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA?s Johnson Space Center.

STS-134 crew during EVA TPS Overview training in the TPS/PABF

NASA Image and Video Library

2009-12-15

JSC2009-E-284900 (15 Dec. 2009) --- NASA astronauts Gregory H. Johnson (center), STS-134 pilot; and Michael Fincke (right), mission specialist; along with European Space Agency astronaut Roberto Vittori, mission specialist, participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA?s Johnson Space Center.

The Influence of Thermoplastic Starch and Banana Fibre Contents on Physical and Thermal Properties of LLDPE

NASA Astrophysics Data System (ADS)

Kahar, A. W. M.; Abduati Salem, A. E.

2017-06-01

Blending of linear low density polyethylene (LLDPE), thermoplastic starch (TPS) and banana fiber (BF) have been studied. Two types of systems were prepared; the matrix having different ratio of LLDPE/TPS and, the LLDPE/TPS composites having 5 - 30 wt% BF. Morphological changes using scanning electron microscope (SEM) were observed and its showed that TPS particle are homogenously dispersed in LLDPE matrix. On the other hand BF was found to be well embedded in TPS phase, showing the good interaction between BF and TPS phases. This observation show an agreement with the Young’s modulus value which is increased with the BF contents. The increment in Young’s modulus value was also attributed to the difficulties in LLDPE/TPS chains movement with the presence of BF.

Surface Catalysis and Characterization of Proposed Candidate TPS for Access-to-Space Vehicles

NASA Technical Reports Server (NTRS)

Stewart, David A.

1997-01-01

Surface properties have been obtained on several classes of thermal protection systems (TPS) using data from both side-arm-reactor and arc-jet facilities. Thermochemical stability, optical properties, and coefficients for atom recombination were determined for candidate TPS proposed for single-stage-to-orbit vehicles. The systems included rigid fibrous insulations, blankets, reinforced carbon carbon, and metals. Test techniques, theories used to define arc-jet and side-arm-reactor flow, and material surface properties are described. Total hemispherical emittance and atom recombination coefficients for each candidate TPS are summarized in the form of polynomial and Arrhenius expressions.

Validation of Dosimetric Leaf Gap (DLG) prior to its implementation in Treatment Planning System (TPS): TrueBeam™ millennium 120 leaf MLC.

PubMed

Shende, Ravindra; Patel, Ganesh

2017-01-01

Objective of present study is to determine optimum value of DLG and its validation prior to being incorporated in TPS for Varian TrueBeam™ millennium 120 leaves MLC. Partial transmission through the rounded leaf ends of the Multi Leaf Collimator (MLC) causes a conflict between the edges of the light field and radiation field. Parameter account for this partial transmission is called Dosimetric Leaf Gap (DLG). The complex high precession technique, such as Intensity Modulated Radiation Therapy (IMRT), entails the modeling of optimum value of DLG inside Eclipse Treatment Planning System (TPS) for precise dose calculation. Distinct synchronized uniformed extension of sweeping dynamic MLC leaf gap fields created by Varian MLC shaper software were use to determine DLG. DLG measurements performed with both 0.13 cc semi-flex ionization chamber and 2D-Array I-Matrix were used to validate the DLG; similarly, values of DLG from TPS were estimated from predicted dose. Similar mathematical approaches were employed to determine DLG from delivered and TPS predicted dose. DLG determined from delivered dose measured with both ionization chamber (DLG Ion ) and I-Matrix (DLG I-Matrix ) compared with DLG estimate from TPS predicted dose (DLG TPS ). Measurements were carried out for all available 6MV, 10MV, 15MV, 6MVFFF and 10MVFFF beam energies. Maximum and minimum DLG deviation between measured and TPS calculated DLG was found to be 0.2 mm and 0.1 mm, respectively. Both of the measured DLGs (DLG Ion and DLG I-Matrix ) were found to be in a very good agreement with estimated DLG from TPS (DLG TPS ). Proposed method proved to be helpful in verifying and validating the DLG value prior to its clinical implementation in TPS.

Thermal design of the space shuttle solid rocket booster

NASA Technical Reports Server (NTRS)

Fisher, R. R.; Vaniman, J. L.; Patterson, W. J.

1985-01-01

The thermal protection systems (TPS) to meet the quick turnaround and low cost required for reuse of the solid rocket booster (SRB) hardware. The TPS development considered the ease of application, changing ascent/reentry environments, and the problem of cleaning the residual insulation upon recovery. A sprayable ablator TPS material was developed. The challenges involved in design and development of this thermal system are discussed.

Verification of surface preparation for adhesive bonding

NASA Technical Reports Server (NTRS)

Myers, Rodney S.

1995-01-01

A survey of solid rocket booster (SRB) production operations identified potential contaminants which might adversely affect bonding operations. Lap shear tests quantified these contaminants' effects on adhesive strength. The most potent contaminants were selected for additional studies on SRB thermal protection system (TPS) bonding processes. Test panels were prepared with predetermined levels of contamination, visually inspected using white and black light, then bonded with three different TPS materials over the unremoved contamination. Bond test data showed that white and black light inspections are adequate inspection methods for TPS bonding operations. Extreme levels of contamination (higher than expected on flight hardware) had an insignificant effect on TPS bond strengths because of the apparent insensitivity of the adhesive system to contamination effects, and the comparatively weak cohesive strength of the TPS materials.

STS-134 crew during EVA TPS Overview training in the TPS/PABF

NASA Image and Video Library

2009-12-15

JSC2009-E-284895 (15 Dec. 2009) --- NASA astronauts Gregory H. Johnson (left), STS-134 pilot; along with astronauts Michael Fincke, Greg Chamitoff and Andrew Feustel (mostly out of frame), all mission specialists, participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA?s Johnson Space Center.

Inspection of the Math Model Tools for On-Orbit Assessment of Impact Damage Report. Version 1.0

NASA Technical Reports Server (NTRS)

Harris, Charles E.; Raju, Ivatury S.; Piascik, Robert S.; Kramer White, Julie; Labbe, Steve G.; Rotter, Hank A.

2005-01-01

In Spring of 2005, the NASA Engineering Safety Center (NESC) was engaged by the Space Shuttle Program (SSP) to peer review the suite of analytical tools being developed to support the determination of impact and damage tolerance of the Orbiter Thermal Protection Systems (TPS). The NESC formed an independent review team with the core disciplines of materials, flight sciences, structures, mechanical analysis and thermal analysis. The Math Model Tools reviewed included damage prediction and stress analysis, aeroheating analysis, and thermal analysis tools. Some tools are physics-based and other tools are empirically-derived. Each tool was created for a specific use and timeframe, including certification, real-time pre-launch assessments, and real-time on-orbit assessments. The tools are used together in an integrated strategy for assessing the ramifications of impact damage to tile and RCC. The NESC teams conducted a peer review of the engineering data package for each Math Model Tool. This report contains the summary of the team observations and recommendations from these reviews.

Petroleum systems used to determine the assessment units in the San Joaquin Basin Province, California: Chapter 8 in Petroleum systems and geologic assessment of oil and gas in the San Joaquin Basin Province, California

USGS Publications Warehouse

Magoon, Leslie B.; Lillis, Paul G.; Peters, Kenneth E.

2009-01-01

The figures and tables for each petroleum system and TPS are as follows: (1) the San Joaquin(?) petroleum system or the Neogene Nonassociated Gas TPS is a natural gas system in the southeast part of the province (figs. 8.3 through 8.8; table 8.5; this volume, chapter 22); (2) the Miocene TPS (this volume, chapters 13, 14, 15, 16, and 17) includes the McLure-Tulare(!) petroleum system north of the Bakersfield Arch (figs. 8.9 through 8.13; table 8.6), and the Antelope-Stevens(!) petroleum system south of the arch (figs. 8.14 through 8.18; table 8.7), and is summarized in figure 8.19; (3) the Eocene TPS (this volume, chapters 18 and 19) combines two petroleum systems, the Tumey-Temblor(.) covering much of the province (figs. 8.20 through 8.24; table 8.8) and the underlying Kreyenhagen-Temblor(!) (figs. 8.25 through 8.29: table 8.9), and is summarized in figure 8.30; (4) the Eocene-Miocene Composite TPS, formed by combining the Miocene and Eocene TPS (this volume, chapter 20); and (5) the Moreno-Nortonville(.) is both a petroleum system and a TPS consisting mainly of natural gas in the northern part of the province (figs. 8.31 through 8.36: table 8.10; this volume, chapter 21). Oil samples with geochemistry from surface seeps and wells used to map these petroleum systems are listed in table 8.11. Finally, the volume of oil and gas expelled by each pod of active source rock was calculated and compared with the discovered hydrocarbons in each petroleum system (figs. 8.37 through 8.39; tables 8.12 and 8.13).

Experimental Study Of SHEFEX II Hypersonic Aerodynamics And Canard Efficiency In H2K

NASA Astrophysics Data System (ADS)

Neeb, D.; Gulhan, A.

2011-05-01

One main objective of the DLR SHEFEX programme is to prove that sharp edged vehicles are capable of performing a re-entry into earth atmosphere by using a simple thermal protection system consisting of flat ceramic tiles. In comparison to blunt nose configurations like the Space shuttle, which are normally used for re-entry configurations, the SHEFEX TPS design is able to significantly reduce the costs and complexity of TPS structures and simultaneously increase the aerodynamic performance of the flight vehicle [1], [2]. To study its characteristics and perform several defined in-flight experiments during re-entry, the vehicle’s attitude will be controlled actively by canards [3]. In the framework of the SHEFEX II project an experimental investigation has been conducted in the hypersonic wind tunnel H2K to characterize the aerodynamic performance of the vehicle in hypersonic flow regime. The model has a modular design to enable the study of a variety of different influencing parameters. Its 4 circumferential canards have been made independently adjustable to account for the simulation of different manoeuvre conditions. To study the control behaviour of the vehicle and validate CFD data, a variation of canard deflections, angle of attack and angle of sideslip have been applied. Tests have been carried out at Mach 7 and 8.7 with a Reynolds number sensitivity study at the lower Mach number. The model was equipped with a six component internal balance to realize accurate coefficient measurements. The flow topology has been analyzed using Schlieren images. Beside general aerodynamic performance and canard efficiencies, flow phenomena like shock impingement on the canards could be determined by Schlieren images as well as by the derived coefficients.

Effects of aerodynamic heating and TPS thermal performance uncertainties on the Shuttle Orbiter

NASA Technical Reports Server (NTRS)

Goodrich, W. D.; Derry, S. M.; Maraia, R. J.

1980-01-01

A procedure for estimating uncertainties in the aerodynamic-heating and thermal protection system (TPS) thermal-performance methodologies developed for the Shuttle Orbiter is presented. This procedure is used in predicting uncertainty bands around expected or nominal TPS thermal responses for the Orbiter during entry. Individual flowfield and TPS parameters that make major contributions to these uncertainty bands are identified and, by statistical considerations, combined in a manner suitable for making engineering estimates of the TPS thermal confidence intervals and temperature margins relative to design limits. Thus, for a fixed TPS design, entry trajectories for future Orbiter missions can be shaped subject to both the thermal-margin and confidence-interval requirements. This procedure is illustrated by assessing the thermal margins offered by selected areas of the existing Orbiter TPS design for an entry trajectory typifying early flight test missions.

Tile-Image Merging and Delivering for Virtual Camera Services on Tiled-Display for Real-Time Remote Collaboration

NASA Astrophysics Data System (ADS)

Choe, Giseok; Nang, Jongho

The tiled-display system has been used as a Computer Supported Cooperative Work (CSCW) environment, in which multiple local (and/or remote) participants cooperate using some shared applications whose outputs are displayed on a large-scale and high-resolution tiled-display, which is controlled by a cluster of PC's, one PC per display. In order to make the collaboration effective, each remote participant should be aware of all CSCW activities on the titled display system in real-time. This paper presents a capturing and delivering mechanism of all activities on titled-display system to remote participants in real-time. In the proposed mechanism, the screen images of all PC's are periodically captured and delivered to the Merging Server that maintains separate buffers to store the captured images from the PCs. The mechanism selects one tile image from each buffer, merges the images to make a screen shot of the whole tiled-display, clips a Region of Interest (ROI), compresses and streams it to remote participants in real-time. A technical challenge in the proposed mechanism is how to select a set of tile images, one from each buffer, for merging so that the tile images displayed at the same time on the tiled-display can be properly merged together. This paper presents three selection algorithms; a sequential selection algorithm, a capturing time based algorithm, and a capturing time and visual consistency based algorithm. It also proposes a mechanism of providing several virtual cameras on tiled-display system to remote participants by concurrently clipping several different ROI's from the same merged tiled-display images, and delivering them after compressing with video encoders requested by the remote participants. By interactively changing and resizing his/her own ROI, a remote participant can check the activities on the tiled-display effectively. Experiments on a 3 × 2 tiled-display system show that the proposed merging algorithm can build a tiled-display image stream synchronously, and the ROI-based clipping and delivering mechanism can provide individual views on the tiled-display system to multiple remote participants in real-time.

Research on thermal protection mechanism of forward-facing cavity and opposing jet combinatorial thermal protection system

NASA Astrophysics Data System (ADS)

Lu, Hai-Bo; Liu, Wei-Qiang

2014-04-01

Validated by the correlated experiments, a nose-tip with forward-facing cavity/opposing jet/the combinatorial configuration of forward-facing cavity and opposing jet thermal protection system (TPS) are investigated numerically. The physical mechanism of these TPS is discussed, and the cooling efficiency of them is compared. The combinatorial system is more suitable to be the TPS for the high speed vehicles which need fly under various flow conditions with long-range and long time.

Conditioning of the vacuum system of the TPS storage ring without baking in situ

NASA Astrophysics Data System (ADS)

Chan, C. K.; Chang, C. C.; Shueh, C.; Yang, I. C.; Wu, L. H.; Chen, B. Y.; Cheng, C. M.; Huang, Y. T.; Chuang, J. Y.; Cheng, Y. T.; Hsiao, Y. M.; Sheng, Albert

2017-04-01

To shorten the machine downtime, a maintenance procedure without baking in situ has been developed and applied to maintain and to upgrade the vacuum system of the TPS storage ring. The data of photon-stimulated desorption (PSD) reveal no obvious discrepancy between baking and not baking the vacuum system in situ. A beam-conditioning dose of extent only 11.8 A h is required to recover quickly the dynamic pressure of an unbaked vacuum system to its pre-intervention value according to the TPS maintenance experience.

Prediction of in-depth gap heating ratios from wing glove model test data. [space shuttle orbiter

NASA Technical Reports Server (NTRS)

1977-01-01

In-depth gap heating ratios were predicted down RSI tile sidewalls based on temperature measurements obtained from the JSC arc-jet Wing Glove model tests in order to develop gap heating ratios which resulted in the best possible fit of test data and to produce a set of engineering verification heating ratios similar in shape to one another which could be used at various body points on the Orbiter during reentry. The Rockwell TPS Multidimensional heat conduction program was used to perform 3-D thermal analyses using a 3.0 in. thick section of a curved RSI tile with 283 nodal points. Correlation with test data shows that the predicted heating ratios were significantly higher down in the gap than the zero pressure values for T/C stacks 39 and 38 on the Wing Glove model. For stack 37 (in a low pressure region), the baseline heating ratio overpredicted the temperature data. This analysis, which showed that the heating ratios were a strong function of the product of pressure and pressure gradient, will be used to compare with recent Gap/Step and Ames Double Wedge test/analysis results in the effort to identify the Orbiter gap response to high delta P flight environment.

WE-AB-201-00: Treatment Planning System Commissioning and QA

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Treatment planning systems (TPS) are a cornerstone of modern radiation therapy. Errors in their commissioning or use can have a devastating impact on many patients. To support safe and high quality care, medical physicists must conduct efficient and proper commissioning, good clinical integration, and ongoing quality assurance (QA) of the TPS. AAPM Task Group 53 and related publications have served as seminal benchmarks for TPS commissioning and QA over the past two decades. Over the same time, continuing innovations have made the TPS even more complex and more central to the clinical process. Medical goals are now expressed in termsmore » of the dose and margins around organs and tissues that are delineated from multiple imaging modalities (CT, MR and PET); and even temporally resolved (i.e., 4D) imaging. This information is passed on to optimization algorithms to establish accelerator movements that are programmed directly for IMRT, VMAT and stereotactic treatments. These advances have made commissioning and QA of the TPS much more challenging. This education session reviews up-to-date experience and guidance on this subject; including the recently published AAPM Medical Physics Practice Guideline (MPPG) #5 “Commissioning and QA of Treatment Planning Dose Calculations: Megavoltage Photon and Electron Beams”. Treatment Planning System Commissioning and QA: Challenges and Opportunities (Greg Salomons) This session will provide some key background and review publications describing prominent incidents relating to TPS commissioning and QA. Traditional approaches have been hardware and feature oriented. They aim to establish a functional configuration and establish specifications for regular testing of features (like dose calculation) to assure stable operation and detect failures. With the advent of more complex systems, more patient-specific testing has also been adopted. A number of actual TPS defects will be presented along with heuristics for identifying similar defects in the future. Finally, the Gamma test has become a popular metric for reporting TPS Commissioning and QA results. It simplifies complex testing into a numerical index, but noisy data and casual application can make it misleading. A brief review of the issues around the use of the Gamma test will be presented. TPS commissioning and QA: A process orientation and application of control charts (Michael Sharpe) A framework for commissioning a treatment planning system will be presented, focusing on preparations, practical aspects of configuration, priorities, specifications, and establishing performance. The complexity of the modern TPS make modular testing of features inadequate, and modern QA tools can provide “too much information” about the performance of techniques like IMRT and VMAT. We have adopted a process orientation and quality tools, like control charts, for ongoing TPS QA and assessment of patient-specific tests. The trending nature of these tools reveals the overall performance of the TPS system, and quantifies the variations that arise from individual plans, discrete calculations, and experimentation based on discrete measurements. Examples demonstrating application of these tools to TPS QA will be presented. TPS commissioning and QA: Incorporating the entire planning process (Sasa Mutic) The TPS and its features do not perform in isolation. Instead, the features and modules are key components in a complex process that begins with CT Simulation and extends to treatment delivery, along with image guidance and verification. Most importantly, the TPS is used by people working in a multi-disciplinary environment. It is very difficult to predict the outcomes of human interactions with software. Therefore, an interdisciplinary approach to training, commissioning and QA will be presented, along with an approach to the physics chart check and end-to-end testing as a tool for TPS QA. The role of standardization and automation in QA will also be discussed. The recommendations of MPPG #5 and practical implementation strategies (Jennifer Smilowitz) The recently published recommendations from Task Group No. 244, Medical Physics Practice Guideline on Commissioning and QA of Treatment Planning Dose Calculations: Megavoltage Photon and Electron Beams will be presented. The recommendations focus on the validation of commissioning data and dose calculations. Tolerance values for non-IMRT beam configurations are summarized based on established criteria and data collected by the IROC. More stringent evaluation criteria for IMRT dose calculations are suggested to test the limitations of the TPS dose algorithms for advanced delivery conditions. The MPPG encourages users to create a suite of validation tests for dose calculation for various conditions for static photon beams, heterogeneities, IMRT/VMAT and electron beams. This test suite is intended to be used for subsequent testing, including TPS software upgrades. In the past, the recommendations of some reports have not been widely implemented due to practical limitations. Implementation strategies, tools and processes developed by multiple centers for efficient and “do-able” MPPG # 5 testing will be presented, as well as a discussion on the overall validation experience. Learning Objectives: Identify some of the key documents relevant for TPS commissioning and QA Understand strategies for testing TPS software Gain a practical knowledge of the Gamma test criteria Increase familiarity with the process of commissioning a TPS Learn about the use of Control Charts for TPS QA Review the role of the TPS in the overall planning process Increase awareness of the link between TPS QA and chart checking Gain an increased appreciation for the importance of interdisciplinary communication Understand the new recommendations from MPPG #5 on TPS Dose Algorithm Commissioning and QC/QA Learn practical implementation processes and tools for MPPG #5 validation recommendations.« less

WE-AB-201-01: Treatment Planning System Commissioning and QA: Challenges and Opportunities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salomons, G.

Treatment planning systems (TPS) are a cornerstone of modern radiation therapy. Errors in their commissioning or use can have a devastating impact on many patients. To support safe and high quality care, medical physicists must conduct efficient and proper commissioning, good clinical integration, and ongoing quality assurance (QA) of the TPS. AAPM Task Group 53 and related publications have served as seminal benchmarks for TPS commissioning and QA over the past two decades. Over the same time, continuing innovations have made the TPS even more complex and more central to the clinical process. Medical goals are now expressed in termsmore » of the dose and margins around organs and tissues that are delineated from multiple imaging modalities (CT, MR and PET); and even temporally resolved (i.e., 4D) imaging. This information is passed on to optimization algorithms to establish accelerator movements that are programmed directly for IMRT, VMAT and stereotactic treatments. These advances have made commissioning and QA of the TPS much more challenging. This education session reviews up-to-date experience and guidance on this subject; including the recently published AAPM Medical Physics Practice Guideline (MPPG) #5 “Commissioning and QA of Treatment Planning Dose Calculations: Megavoltage Photon and Electron Beams”. Treatment Planning System Commissioning and QA: Challenges and Opportunities (Greg Salomons) This session will provide some key background and review publications describing prominent incidents relating to TPS commissioning and QA. Traditional approaches have been hardware and feature oriented. They aim to establish a functional configuration and establish specifications for regular testing of features (like dose calculation) to assure stable operation and detect failures. With the advent of more complex systems, more patient-specific testing has also been adopted. A number of actual TPS defects will be presented along with heuristics for identifying similar defects in the future. Finally, the Gamma test has become a popular metric for reporting TPS Commissioning and QA results. It simplifies complex testing into a numerical index, but noisy data and casual application can make it misleading. A brief review of the issues around the use of the Gamma test will be presented. TPS commissioning and QA: A process orientation and application of control charts (Michael Sharpe) A framework for commissioning a treatment planning system will be presented, focusing on preparations, practical aspects of configuration, priorities, specifications, and establishing performance. The complexity of the modern TPS make modular testing of features inadequate, and modern QA tools can provide “too much information” about the performance of techniques like IMRT and VMAT. We have adopted a process orientation and quality tools, like control charts, for ongoing TPS QA and assessment of patient-specific tests. The trending nature of these tools reveals the overall performance of the TPS system, and quantifies the variations that arise from individual plans, discrete calculations, and experimentation based on discrete measurements. Examples demonstrating application of these tools to TPS QA will be presented. TPS commissioning and QA: Incorporating the entire planning process (Sasa Mutic) The TPS and its features do not perform in isolation. Instead, the features and modules are key components in a complex process that begins with CT Simulation and extends to treatment delivery, along with image guidance and verification. Most importantly, the TPS is used by people working in a multi-disciplinary environment. It is very difficult to predict the outcomes of human interactions with software. Therefore, an interdisciplinary approach to training, commissioning and QA will be presented, along with an approach to the physics chart check and end-to-end testing as a tool for TPS QA. The role of standardization and automation in QA will also be discussed. The recommendations of MPPG #5 and practical implementation strategies (Jennifer Smilowitz) The recently published recommendations from Task Group No. 244, Medical Physics Practice Guideline on Commissioning and QA of Treatment Planning Dose Calculations: Megavoltage Photon and Electron Beams will be presented. The recommendations focus on the validation of commissioning data and dose calculations. Tolerance values for non-IMRT beam configurations are summarized based on established criteria and data collected by the IROC. More stringent evaluation criteria for IMRT dose calculations are suggested to test the limitations of the TPS dose algorithms for advanced delivery conditions. The MPPG encourages users to create a suite of validation tests for dose calculation for various conditions for static photon beams, heterogeneities, IMRT/VMAT and electron beams. This test suite is intended to be used for subsequent testing, including TPS software upgrades. In the past, the recommendations of some reports have not been widely implemented due to practical limitations. Implementation strategies, tools and processes developed by multiple centers for efficient and “do-able” MPPG #5 testing will be presented, as well as a discussion on the overall validation experience. Learning Objectives: Identify some of the key documents relevant for TPS commissioning and QA Understand strategies for testing TPS software Gain a practical knowledge of the Gamma test criteria Increase familiarity with the process of commissioning a TPS Learn about the use of Control Charts for TPS QA Review the role of the TPS in the overall planning process Increase awareness of the link between TPS QA and chart checking Gain an increased appreciation for the importance of interdisciplinary communication Understand the new recommendations from MPPG #5 on TPS Dose Algorithm Commissioning and QC/QA Learn practical implementation processes and tools for MPPG #5 validation recommendations.« less

Physical principles for DNA tile self-assembly.

PubMed

Evans, Constantine G; Winfree, Erik

2017-06-19

DNA tiles provide a promising technique for assembling structures with nanoscale resolution through self-assembly by basic interactions rather than top-down assembly of individual structures. Tile systems can be programmed to grow based on logical rules, allowing for a small number of tile types to assemble large, complex assemblies that can retain nanoscale resolution. Such algorithmic systems can even assemble different structures using the same tiles, based on inputs that seed the growth. While programming and theoretical analysis of tile self-assembly often makes use of abstract logical models of growth, experimentally implemented systems are governed by nanoscale physical processes that can lead to very different behavior, more accurately modeled by taking into account the thermodynamics and kinetics of tile attachment and detachment in solution. This review discusses the relationships between more abstract and more physically realistic tile assembly models. A central concern is how consideration of model differences enables the design of tile systems that robustly exhibit the desired abstract behavior in realistic physical models and in experimental implementations. Conversely, we identify situations where self-assembly in abstract models can not be well-approximated by physically realistic models, putting constraints on physical relevance of the abstract models. To facilitate the discussion, we introduce a unified model of tile self-assembly that clarifies the relationships between several well-studied models in the literature. Throughout, we highlight open questions regarding the physical principles for DNA tile self-assembly.

Assessment of Technologies for the Space Shuttle External Tank Thermal Protection System and Recommendations for Technology Improvement. Part 2; Structural Analysis Technologies and Modeling Practices

NASA Technical Reports Server (NTRS)

Knight, Norman F., Jr.; Nemeth, Michael P.; Hilburger, Mark W.

2004-01-01

A technology review and assessment of modeling and analysis efforts underway in support of a safe return to flight of the thermal protection system (TPS) for the Space Shuttle external tank (ET) are summarized. This review and assessment effort focuses on the structural modeling and analysis practices employed for ET TPS foam design and analysis and on identifying analysis capabilities needed in the short-term and long-term. The current understanding of the relationship between complex flight environments and ET TPS foam failure modes are reviewed as they relate to modeling and analysis. A literature review on modeling and analysis of TPS foam material systems is also presented. Finally, a review of modeling and analysis tools employed in the Space Shuttle Program is presented for the ET TPS acreage and close-out foam regions. This review includes existing simplified engineering analysis tools are well as finite element analysis procedures.

Return to Flight Resource Reel 1 of 2

NASA Technical Reports Server (NTRS)

2005-01-01

A video presentation detailing the tests performed on the Space Shuttle Discovery in preparation for its return to flight is shown. The tests include: 1) Reinforced Carbon-Carbon (RCC) Impact Test Article; 2) RCC Foam Impact Testing; 3) Thermal Protection System (TPS) Ice Impact Testing featuring Justin Kerr, Project Engineer; 4) Wing Leading Edge Wireless Sensors featuring Karl Kiefer, President and CEO of Invocon, and Kevin Champaigne of Invocon; 5) TPS Repair Testing KC-135 Zero-G Environment featuring Soichi Noguchi, Mission Specialist; 6) TPS Extravehicular Activity Tool Demonstration; 7) TPS Repair Testing Vacuum Glove box; 8) TPS Repair Testing Human Thermal Vacuum Chamber; 9) TPS Reentry Testing Atmospheric Reentry Materials and Structures Evaluation Facility; 10) TPS Alternative Repair Concept; 11) Lora Bailey Lead Engineer for EVA Tools; 12) Reinforced Carbon-Carbon ATK Thiokol Plug Repair Animation; 13) 3-Percent Model Build-Up; and 14) Wind Tunnel Testing RCC Aging Research Ballistic Testing.

STS-134 crew during EVA TPS Overview training in the TPS/PABF

NASA Image and Video Library

2009-12-15

JSC2009-E-284891 (15 Dec. 2009) --- STS-134 crew members participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA?s Johnson Space Center. Pictured from the right are NASA astronauts Andrew Feustel, Greg Chamitoff, Michael Fincke, all mission specialists; along with NASA astronaut Gregory H. Johnson, pilot; and European Space Agency astronaut Roberto Vittori, mission specialist.

Strategies and Approaches to TPS Design

NASA Technical Reports Server (NTRS)

Kolodziej, Paul

2005-01-01

Thermal protection systems (TPS) insulate planetary probes and Earth re-entry vehicles from the aerothermal heating experienced during hypersonic deceleration to the planet s surface. The systems are typically designed with some additional capability to compensate for both variations in the TPS material and for uncertainties in the heating environment. This additional capability, or robustness, also provides a surge capability for operating under abnormal severe conditions for a short period of time, and for unexpected events, such as meteoroid impact damage, that would detract from the nominal performance. Strategies and approaches to developing robust designs must also minimize mass because an extra kilogram of TPS displaces one kilogram of payload. Because aircraft structures must be optimized for minimum mass, reliability-based design approaches for mechanical components exist that minimize mass. Adapting these existing approaches to TPS component design takes advantage of the extensive work, knowledge, and experience from nearly fifty years of reliability-based design of mechanical components. A Non-Dimensional Load Interference (NDLI) method for calculating the thermal reliability of TPS components is presented in this lecture and applied to several examples. A sensitivity analysis from an existing numerical simulation of a carbon phenolic TPS provides insight into the effects of the various design parameters, and is used to demonstrate how sensitivity analysis may be used with NDLI to develop reliability-based designs of TPS components.

WE-AB-201-03: TPS Commissioning and QA: Incorporating the Entire Planning Process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mutic, S.

Treatment planning systems (TPS) are a cornerstone of modern radiation therapy. Errors in their commissioning or use can have a devastating impact on many patients. To support safe and high quality care, medical physicists must conduct efficient and proper commissioning, good clinical integration, and ongoing quality assurance (QA) of the TPS. AAPM Task Group 53 and related publications have served as seminal benchmarks for TPS commissioning and QA over the past two decades. Over the same time, continuing innovations have made the TPS even more complex and more central to the clinical process. Medical goals are now expressed in termsmore » of the dose and margins around organs and tissues that are delineated from multiple imaging modalities (CT, MR and PET); and even temporally resolved (i.e., 4D) imaging. This information is passed on to optimization algorithms to establish accelerator movements that are programmed directly for IMRT, VMAT and stereotactic treatments. These advances have made commissioning and QA of the TPS much more challenging. This education session reviews up-to-date experience and guidance on this subject; including the recently published AAPM Medical Physics Practice Guideline (MPPG) #5 “Commissioning and QA of Treatment Planning Dose Calculations: Megavoltage Photon and Electron Beams”. Treatment Planning System Commissioning and QA: Challenges and Opportunities (Greg Salomons) This session will provide some key background and review publications describing prominent incidents relating to TPS commissioning and QA. Traditional approaches have been hardware and feature oriented. They aim to establish a functional configuration and establish specifications for regular testing of features (like dose calculation) to assure stable operation and detect failures. With the advent of more complex systems, more patient-specific testing has also been adopted. A number of actual TPS defects will be presented along with heuristics for identifying similar defects in the future. Finally, the Gamma test has become a popular metric for reporting TPS Commissioning and QA results. It simplifies complex testing into a numerical index, but noisy data and casual application can make it misleading. A brief review of the issues around the use of the Gamma test will be presented. TPS commissioning and QA: A process orientation and application of control charts (Michael Sharpe) A framework for commissioning a treatment planning system will be presented, focusing on preparations, practical aspects of configuration, priorities, specifications, and establishing performance. The complexity of the modern TPS make modular testing of features inadequate, and modern QA tools can provide “too much information” about the performance of techniques like IMRT and VMAT. We have adopted a process orientation and quality tools, like control charts, for ongoing TPS QA and assessment of patient-specific tests. The trending nature of these tools reveals the overall performance of the TPS system, and quantifies the variations that arise from individual plans, discrete calculations, and experimentation based on discrete measurements. Examples demonstrating application of these tools to TPS QA will be presented. TPS commissioning and QA: Incorporating the entire planning process (Sasa Mutic) The TPS and its features do not perform in isolation. Instead, the features and modules are key components in a complex process that begins with CT Simulation and extends to treatment delivery, along with image guidance and verification. Most importantly, the TPS is used by people working in a multi-disciplinary environment. It is very difficult to predict the outcomes of human interactions with software. Therefore, an interdisciplinary approach to training, commissioning and QA will be presented, along with an approach to the physics chart check and end-to-end testing as a tool for TPS QA. The role of standardization and automation in QA will also be discussed. The recommendations of MPPG #5 and practical implementation strategies (Jennifer Smilowitz) The recently published recommendations from Task Group No. 244, Medical Physics Practice Guideline on Commissioning and QA of Treatment Planning Dose Calculations: Megavoltage Photon and Electron Beams will be presented. The recommendations focus on the validation of commissioning data and dose calculations. Tolerance values for non-IMRT beam configurations are summarized based on established criteria and data collected by the IROC. More stringent evaluation criteria for IMRT dose calculations are suggested to test the limitations of the TPS dose algorithms for advanced delivery conditions. The MPPG encourages users to create a suite of validation tests for dose calculation for various conditions for static photon beams, heterogeneities, IMRT/VMAT and electron beams. This test suite is intended to be used for subsequent testing, including TPS software upgrades. In the past, the recommendations of some reports have not been widely implemented due to practical limitations. Implementation strategies, tools and processes developed by multiple centers for efficient and “do-able” MPPG #5 testing will be presented, as well as a discussion on the overall validation experience. Learning Objectives: Identify some of the key documents relevant for TPS commissioning and QA Understand strategies for testing TPS software Gain a practical knowledge of the Gamma test criteria Increase familiarity with the process of commissioning a TPS Learn about the use of Control Charts for TPS QA Review the role of the TPS in the overall planning process Increase awareness of the link between TPS QA and chart checking Gain an increased appreciation for the importance of interdisciplinary communication Understand the new recommendations from MPPG #5 on TPS Dose Algorithm Commissioning and QC/QA Learn practical implementation processes and tools for MPPG #5 validation recommendations.« less

WE-AB-201-02: TPS Commissioning and QA: A Process Orientation and Application of Control Charts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharpe, M.

Treatment planning systems (TPS) are a cornerstone of modern radiation therapy. Errors in their commissioning or use can have a devastating impact on many patients. To support safe and high quality care, medical physicists must conduct efficient and proper commissioning, good clinical integration, and ongoing quality assurance (QA) of the TPS. AAPM Task Group 53 and related publications have served as seminal benchmarks for TPS commissioning and QA over the past two decades. Over the same time, continuing innovations have made the TPS even more complex and more central to the clinical process. Medical goals are now expressed in termsmore » of the dose and margins around organs and tissues that are delineated from multiple imaging modalities (CT, MR and PET); and even temporally resolved (i.e., 4D) imaging. This information is passed on to optimization algorithms to establish accelerator movements that are programmed directly for IMRT, VMAT and stereotactic treatments. These advances have made commissioning and QA of the TPS much more challenging. This education session reviews up-to-date experience and guidance on this subject; including the recently published AAPM Medical Physics Practice Guideline (MPPG) #5 “Commissioning and QA of Treatment Planning Dose Calculations: Megavoltage Photon and Electron Beams”. Treatment Planning System Commissioning and QA: Challenges and Opportunities (Greg Salomons) This session will provide some key background and review publications describing prominent incidents relating to TPS commissioning and QA. Traditional approaches have been hardware and feature oriented. They aim to establish a functional configuration and establish specifications for regular testing of features (like dose calculation) to assure stable operation and detect failures. With the advent of more complex systems, more patient-specific testing has also been adopted. A number of actual TPS defects will be presented along with heuristics for identifying similar defects in the future. Finally, the Gamma test has become a popular metric for reporting TPS Commissioning and QA results. It simplifies complex testing into a numerical index, but noisy data and casual application can make it misleading. A brief review of the issues around the use of the Gamma test will be presented. TPS commissioning and QA: A process orientation and application of control charts (Michael Sharpe) A framework for commissioning a treatment planning system will be presented, focusing on preparations, practical aspects of configuration, priorities, specifications, and establishing performance. The complexity of the modern TPS make modular testing of features inadequate, and modern QA tools can provide “too much information” about the performance of techniques like IMRT and VMAT. We have adopted a process orientation and quality tools, like control charts, for ongoing TPS QA and assessment of patient-specific tests. The trending nature of these tools reveals the overall performance of the TPS system, and quantifies the variations that arise from individual plans, discrete calculations, and experimentation based on discrete measurements. Examples demonstrating application of these tools to TPS QA will be presented. TPS commissioning and QA: Incorporating the entire planning process (Sasa Mutic) The TPS and its features do not perform in isolation. Instead, the features and modules are key components in a complex process that begins with CT Simulation and extends to treatment delivery, along with image guidance and verification. Most importantly, the TPS is used by people working in a multi-disciplinary environment. It is very difficult to predict the outcomes of human interactions with software. Therefore, an interdisciplinary approach to training, commissioning and QA will be presented, along with an approach to the physics chart check and end-to-end testing as a tool for TPS QA. The role of standardization and automation in QA will also be discussed. The recommendations of MPPG #5 and practical implementation strategies (Jennifer Smilowitz) The recently published recommendations from Task Group No. 244, Medical Physics Practice Guideline on Commissioning and QA of Treatment Planning Dose Calculations: Megavoltage Photon and Electron Beams will be presented. The recommendations focus on the validation of commissioning data and dose calculations. Tolerance values for non-IMRT beam configurations are summarized based on established criteria and data collected by the IROC. More stringent evaluation criteria for IMRT dose calculations are suggested to test the limitations of the TPS dose algorithms for advanced delivery conditions. The MPPG encourages users to create a suite of validation tests for dose calculation for various conditions for static photon beams, heterogeneities, IMRT/VMAT and electron beams. This test suite is intended to be used for subsequent testing, including TPS software upgrades. In the past, the recommendations of some reports have not been widely implemented due to practical limitations. Implementation strategies, tools and processes developed by multiple centers for efficient and “do-able” MPPG #5 testing will be presented, as well as a discussion on the overall validation experience. Learning Objectives: Identify some of the key documents relevant for TPS commissioning and QA Understand strategies for testing TPS software Gain a practical knowledge of the Gamma test criteria Increase familiarity with the process of commissioning a TPS Learn about the use of Control Charts for TPS QA Review the role of the TPS in the overall planning process Increase awareness of the link between TPS QA and chart checking Gain an increased appreciation for the importance of interdisciplinary communication Understand the new recommendations from MPPG #5 on TPS Dose Algorithm Commissioning and QC/QA Learn practical implementation processes and tools for MPPG #5 validation recommendations.« less

A Global User-Driven Model for Tile Prefetching in Web Geographical Information Systems.

PubMed

Pan, Shaoming; Chong, Yanwen; Zhang, Hang; Tan, Xicheng

2017-01-01

A web geographical information system is a typical service-intensive application. Tile prefetching and cache replacement can improve cache hit ratios by proactively fetching tiles from storage and replacing the appropriate tiles from the high-speed cache buffer without waiting for a client's requests, which reduces disk latency and improves system access performance. Most popular prefetching strategies consider only the relative tile popularities to predict which tile should be prefetched or consider only a single individual user's access behavior to determine which neighbor tiles need to be prefetched. Some studies show that comprehensively considering all users' access behaviors and all tiles' relationships in the prediction process can achieve more significant improvements. Thus, this work proposes a new global user-driven model for tile prefetching and cache replacement. First, based on all users' access behaviors, a type of expression method for tile correlation is designed and implemented. Then, a conditional prefetching probability can be computed based on the proposed correlation expression mode. Thus, some tiles to be prefetched can be found by computing and comparing the conditional prefetching probability from the uncached tiles set and, similarly, some replacement tiles can be found in the cache buffer according to multi-step prefetching. Finally, some experiments are provided comparing the proposed model with other global user-driven models, other single user-driven models, and other client-side prefetching strategies. The results show that the proposed model can achieve a prefetching hit rate in approximately 10.6% ~ 110.5% higher than the compared methods.

Comparison of performance of tile drainage routines in SWAT 2009 and 2012 in an extensively tile-drained watershed in Midwest

USDA-ARS?s Scientific Manuscript database

Subsurface tile drainage systems are widely used in agricultural watersheds in the Midwestern U.S. Tile drainage systems enable the Midwest area to become highly productive agricultural lands, but can also create environmental problems, for example nitrate-N contamination associated with drainage w...

Total body irradiation, toward optimal individual delivery: dose evaluation with metal oxide field effect transistors, thermoluminescence detectors, and a treatment planning system.

PubMed

Bloemen-van Gurp, Esther J; Mijnheer, Ben J; Verschueren, Tom A M; Lambin, Philippe

2007-11-15

To predict the three-dimensional dose distribution of our total body irradiation technique, using a commercial treatment planning system (TPS). In vivo dosimetry, using metal oxide field effect transistors (MOSFETs) and thermoluminescence detectors (TLDs), was used to verify the calculated dose distributions. A total body computed tomography scan was performed and loaded into our TPS, and a three-dimensional-dose distribution was generated. In vivo dosimetry was performed at five locations on the patient. Entrance and exit dose values were converted to midline doses using conversion factors, previously determined with phantom measurements. The TPS-predicted dose values were compared with the MOSFET and TLD in vivo dose values. The MOSFET and TLD dose values agreed within 3.0% and the MOSFET and TPS data within 0.5%. The convolution algorithm of the TPS, which is routinely applied in the clinic, overestimated the dose in the lung region. Using a superposition algorithm reduced the calculated lung dose by approximately 3%. The dose inhomogeneity, as predicted by the TPS, can be reduced using a simple intensity-modulated radiotherapy technique. The use of a TPS to calculate the dose distributions in individual patients during total body irradiation is strongly recommended. Using a TPS gives good insight of the over- and underdosage in a patient and the influence of patient positioning on dose homogeneity. MOSFETs are suitable for in vivo dosimetry purposes during total body irradiation, when using appropriate conversion factors. The MOSFET, TLD, and TPS results agreed within acceptable margins.

STS-134 crew during EVA TPS Overview training in the TPS/PABF

NASA Image and Video Library

2009-12-15

JSC2009-E-284897 (15 Dec. 2009) --- STS-134 crew members participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA?s Johnson Space Center. Pictured from the right are NASA astronauts Andrew Feustel, Greg Chamitoff, Michael Fincke, all mission specialists; along with NASA astronaut Gregory H. Johnson, pilot; and European Space Agency astronaut Roberto Vittori, mission specialist. John Ray (left) assisted the crew members.

TPS: From Arc-Jet to Flight

NASA Technical Reports Server (NTRS)

Buslog, Stanley A.

2004-01-01

This slide presentation reviews the testing of thermal protection system materials. All space vehicles that reenter Earth's atmosphere from either LEO or from Lunar/Mars missions require thermal protection system (TPS) materials. These TPS materials requires ground test facilities that simulate the aerothermodynamic environments experienced by reentry. The existing arc-jet facility requires expansion to combine convective and radiation heating and to test the capability to protect with the CO2 atmosphere that will be encountered for Martian entry.

Agreement Between Institutional Measurements and Treatment Planning System Calculations for Basic Dosimetric Parameters as Measured by the Imaging and Radiation Oncology Core-Houston

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kerns, James R.; Followill, David S.; Imaging and Radiation Oncology Core-Houston, The University of Texas Health Science Center-Houston, Houston, Texas

Purpose: To compare radiation machine measurement data collected by the Imaging and Radiation Oncology Core at Houston (IROC-H) with institutional treatment planning system (TPS) values, to identify parameters with large differences in agreement; the findings will help institutions focus their efforts to improve the accuracy of their TPS models. Methods and Materials: Between 2000 and 2014, IROC-H visited more than 250 institutions and conducted independent measurements of machine dosimetric data points, including percentage depth dose, output factors, off-axis factors, multileaf collimator small fields, and wedge data. We compared these data with the institutional TPS values for the same points bymore » energy, class, and parameter to identify differences and similarities using criteria involving both the medians and standard deviations for Varian linear accelerators. Distributions of differences between machine measurements and institutional TPS values were generated for basic dosimetric parameters. Results: On average, intensity modulated radiation therapy–style and stereotactic body radiation therapy–style output factors and upper physical wedge output factors were the most problematic. Percentage depth dose, jaw output factors, and enhanced dynamic wedge output factors agreed best between the IROC-H measurements and the TPS values. Although small differences were shown between 2 common TPS systems, neither was superior to the other. Parameter agreement was constant over time from 2000 to 2014. Conclusions: Differences in basic dosimetric parameters between machine measurements and TPS values vary widely depending on the parameter, although agreement does not seem to vary by TPS and has not changed over time. Intensity modulated radiation therapy–style output factors, stereotactic body radiation therapy–style output factors, and upper physical wedge output factors had the largest disagreement and should be carefully modeled to ensure accuracy.« less

Investigation of Fundamental Modeling and Thermal Performance Issues for a Metallic Thermal Protection System Design

NASA Technical Reports Server (NTRS)

Blosser, Max L.

2002-01-01

A study was performed to develop an understanding of the key factors that govern the performance of metallic thermal protection systems for reusable launch vehicles. A current advanced metallic thermal protection system (TPS) concept was systematically analyzed to discover the most important factors governing the thermal performance of metallic TPS. A large number of relevant factors that influence the thermal analysis and thermal performance of metallic TPS were identified and quantified. Detailed finite element models were developed for predicting the thermal performance of design variations of the advanced metallic TPS concept mounted on a simple, unstiffened structure. The computational models were also used, in an automated iterative procedure, for sizing the metallic TPS to maintain the structure below a specified temperature limit. A statistical sensitivity analysis method, based on orthogonal matrix techniques used in robust design, was used to quantify and rank the relative importance of the various modeling and design factors considered in this study. Results of the study indicate that radiation, even in small gaps between panels, can reduce significantly the thermal performance of metallic TPS, so that gaps should be eliminated by design if possible. Thermal performance was also shown to be sensitive to several analytical assumptions that should be chosen carefully. One of the factors that was found to have the greatest effect on thermal performance is the heat capacity of the underlying structure. Therefore the structure and TPS should be designed concurrently.

WE-AB-201-04: The Recommendations of MPPG #5 and Practical Implementation Strategies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smilowitz, J.

Treatment planning systems (TPS) are a cornerstone of modern radiation therapy. Errors in their commissioning or use can have a devastating impact on many patients. To support safe and high quality care, medical physicists must conduct efficient and proper commissioning, good clinical integration, and ongoing quality assurance (QA) of the TPS. AAPM Task Group 53 and related publications have served as seminal benchmarks for TPS commissioning and QA over the past two decades. Over the same time, continuing innovations have made the TPS even more complex and more central to the clinical process. Medical goals are now expressed in termsmore » of the dose and margins around organs and tissues that are delineated from multiple imaging modalities (CT, MR and PET); and even temporally resolved (i.e., 4D) imaging. This information is passed on to optimization algorithms to establish accelerator movements that are programmed directly for IMRT, VMAT and stereotactic treatments. These advances have made commissioning and QA of the TPS much more challenging. This education session reviews up-to-date experience and guidance on this subject; including the recently published AAPM Medical Physics Practice Guideline (MPPG) #5 “Commissioning and QA of Treatment Planning Dose Calculations: Megavoltage Photon and Electron Beams”. Treatment Planning System Commissioning and QA: Challenges and Opportunities (Greg Salomons) This session will provide some key background and review publications describing prominent incidents relating to TPS commissioning and QA. Traditional approaches have been hardware and feature oriented. They aim to establish a functional configuration and establish specifications for regular testing of features (like dose calculation) to assure stable operation and detect failures. With the advent of more complex systems, more patient-specific testing has also been adopted. A number of actual TPS defects will be presented along with heuristics for identifying similar defects in the future. Finally, the Gamma test has become a popular metric for reporting TPS Commissioning and QA results. It simplifies complex testing into a numerical index, but noisy data and casual application can make it misleading. A brief review of the issues around the use of the Gamma test will be presented. TPS commissioning and QA: A process orientation and application of control charts (Michael Sharpe) A framework for commissioning a treatment planning system will be presented, focusing on preparations, practical aspects of configuration, priorities, specifications, and establishing performance. The complexity of the modern TPS make modular testing of features inadequate, and modern QA tools can provide “too much information” about the performance of techniques like IMRT and VMAT. We have adopted a process orientation and quality tools, like control charts, for ongoing TPS QA and assessment of patient-specific tests. The trending nature of these tools reveals the overall performance of the TPS system, and quantifies the variations that arise from individual plans, discrete calculations, and experimentation based on discrete measurements. Examples demonstrating application of these tools to TPS QA will be presented. TPS commissioning and QA: Incorporating the entire planning process (Sasa Mutic) The TPS and its features do not perform in isolation. Instead, the features and modules are key components in a complex process that begins with CT Simulation and extends to treatment delivery, along with image guidance and verification. Most importantly, the TPS is used by people working in a multi-disciplinary environment. It is very difficult to predict the outcomes of human interactions with software. Therefore, an interdisciplinary approach to training, commissioning and QA will be presented, along with an approach to the physics chart check and end-to-end testing as a tool for TPS QA. The role of standardization and automation in QA will also be discussed. The recommendations of MPPG #5 and practical implementation strategies (Jennifer Smilowitz) The recently published recommendations from Task Group No. 244, Medical Physics Practice Guideline on Commissioning and QA of Treatment Planning Dose Calculations: Megavoltage Photon and Electron Beams will be presented. The recommendations focus on the validation of commissioning data and dose calculations. Tolerance values for non-IMRT beam configurations are summarized based on established criteria and data collected by the IROC. More stringent evaluation criteria for IMRT dose calculations are suggested to test the limitations of the TPS dose algorithms for advanced delivery conditions. The MPPG encourages users to create a suite of validation tests for dose calculation for various conditions for static photon beams, heterogeneities, IMRT/VMAT and electron beams. This test suite is intended to be used for subsequent testing, including TPS software upgrades. In the past, the recommendations of some reports have not been widely implemented due to practical limitations. Implementation strategies, tools and processes developed by multiple centers for efficient and “do-able” MPPG #5 testing will be presented, as well as a discussion on the overall validation experience. Learning Objectives: Identify some of the key documents relevant for TPS commissioning and QA Understand strategies for testing TPS software Gain a practical knowledge of the Gamma test criteria Increase familiarity with the process of commissioning a TPS Learn about the use of Control Charts for TPS QA Review the role of the TPS in the overall planning process Increase awareness of the link between TPS QA and chart checking Gain an increased appreciation for the importance of interdisciplinary communication Understand the new recommendations from MPPG #5 on TPS Dose Algorithm Commissioning and QC/QA Learn practical implementation processes and tools for MPPG #5 validation recommendations.« less

Ceramic Matrix Composite (CMC) Thermal Protection Systems (TPS) and Hot Structures for Hypersonic Vehicles

NASA Technical Reports Server (NTRS)

Glass, David E.

2008-01-01

Thermal protection systems (TPS) and hot structures are required for a range of hypersonic vehicles ranging from ballistic reentry to hypersonic cruise vehicles, both within Earth's atmosphere and non-Earth atmospheres. The focus of this paper is on air breathing hypersonic vehicles in the Earth's atmosphere. This includes single-stage to orbit (SSTO), two-stage to orbit (TSTO) accelerators, access to space vehicles, and hypersonic cruise vehicles. This paper will start out with a brief discussion of aerodynamic heating and thermal management techniques to address the high heating, followed by an overview of TPS for rocket-launched and air-breathing vehicles. The argument is presented that as we move from rocket-based vehicles to air-breathing vehicles, we need to move away from the insulated airplane approach used on the Space Shuttle Orbiter to a wide range of TPS and hot structure approaches. The primary portion of the paper will discuss issues and design options for CMC TPS and hot structure components, including leading edges, acreage TPS, and control surfaces. The current state-of-the-art will be briefly discussed for some of the components. The two primary technical challenges impacting the use of CMC TPS and hot structures for hypersonic vehicles are environmental durability and fabrication, and will be discussed briefly.

Woven TPS Enabling Missions Beyond Heritage Carbon Phenolic

NASA Technical Reports Server (NTRS)

Stackpoole, Mairead; Venkatapathy, Ethiraj; Feldman, Jay

2013-01-01

Woven Thermal Protection Systems (WTPS) is a new TPS concept that is funded by NASAs Office of the Chief Technologist (OCT) Game Changing Division. The WTPS project demonstrates the potential for manufacturing many TPS architectures capable of performances demanded by the many potential solar system exploration missions. Currently, missions that encounter heat fluxes in the range of 1500 4000 W/sq cm and pressures greater than 1.5 atm have very limited TPS options - only one proven material, fully dense Carbon Phenolic, is currently available for these missions. However, fully dense carbon phenolic is only mass efficient at heat fluxes greater than 4000 W/sq cm, and current mission designs suffer this mass inefficiency for lack of an alternative mid-density TPS. WTPS not only bridges this TPS gap but also offers a replacement for carbon phenolic, which itself requires a significant and costly redevelopment effort to re-establish its capability for use in the high heat flux missions recently prioritized in the NRC Decadal survey, including probe missions to Venus, Saturn and Neptune. This presentation will introduce some woven TPS architectures considered in this project and summarize some recent arc jet testing to evaluate the performance of fully dense and mid density WTPS. Performance comparisons to heritage carbon phenolic will be drawn where applicable.

Characterization of layered silicate-reinforced blends of thermoplastic starch (TPS) and poly(butylene adipate-co-terephthalate).

PubMed

Lendvai, László; Apostolov, Anton; Karger-Kocsis, József

2017-10-01

A two-step melt blending procedure was used to produce binary systems composed of thermoplastic starch (TPS) and poly(butylene adipate-co-terephthalate) (PBAT). To improve the properties of the blends, two different layered silicates, viz. bentonite (BT) and organically modified montmorillonite (oMMT) were incorporated. First, TPS and its layered silicate nanocomposites were prepared via extrusion compounding during which starch was plasticized with glycerol and water. In the second step, PBAT was added to TPS/layered silicate to produce blends in a batch-type mixer. Mechanical and thermal properties were determined. The blends showed acceptable ductility over 50wt.% PBAT content, although at the cost of strength and stiffness. By contrast to oMMT the BT became intercalated in TPS and TPS/PBAT blends. The reinforcing effect of BT and oMMT was most prominent for the glassy states of both TPS and TPS/PBAT blends. Thermal, and thermooxidative properties were not significantly affected by the presence of layered silicates. Copyright © 2017 Elsevier Ltd. All rights reserved.

Thermal-Structural Evaluation of TD Ni-20Cr Thermal Protection System Panels

NASA Technical Reports Server (NTRS)

Eidinoff, H. L.; Rose, L.

1974-01-01

The results of a thermal-structural test program to verify the performance of a metallic/radiative Thermal Protection System (TPS) under reentry conditions are presented. This TPS panel is suitable for multiple reentry, high L/D space vehicles, such as the NASA space shuttle, having surface temperatures up to 1200 C (2200 F). The TPS panel tested consists of a corrugation-stiffened, beaded-skin TD Ni-20Cr metallic heat shield backed by a flexible fibrous quartz and radiative shield insulative system. Test conditions simulated the critical heating and aerodynamic pressure environments expected during 100 repeated missions of a reentry vehicle. Temperatures were measured during each reentry cycle; heat-shield flatness surveys to measure permanent set of the metallic components were made every 10 cycles. The TPS panel, in spite of localized surface failures, performed its designated function.

Modeling the Relationship Between Porosity and Permeability During Oxidation of Ablative Materials

NASA Technical Reports Server (NTRS)

Thornton, John M.; Panerai, Francesco; Ferguson, Joseph C.; Borner, Arnaud; Mansour, Nagi N.

2017-01-01

The ablative materials used in thermal protection systems (TPS) undergo oxidation during atmospheric entry which leads to an in-depth change in both permeability and porosity. These properties have a significant affect on heat transfer in a TPS during entry. X-ray micro-tomography has provided 3D images capturing the micro-structure of TPS materials. In this study, we use micro-tomography based simulations to create high-fidelity models relating permeability to porosity during oxidation of FiberForm, the carbon fiber preform of the Phenolic Impregnated Carbon Ablator (PICA) often used as a TPS material. The goal of this study is to inform full-scale models and reduce uncertainty in TPS modeling.

The Paris System for Reporting Urinary Cytology: The Quest to Develop a Standardized Terminology.

PubMed

Barkan, Güliz A; Wojcik, Eva M; Nayar, Ritu; Savic-Prince, Spasenija; Quek, Marcus L; Kurtycz, Daniel F I; Rosenthal, Dorothy L

2016-07-01

The main purpose of urine cytology is to detect high-grade urothelial carcinoma. With this principle in mind, The Paris System (TPS) Working Group, composed of cytopathologists, surgical pathologists, and urologists, has proposed and published a standardized reporting system that includes specific diagnostic categories and cytomorphologic criteria for the reliable diagnosis of high-grade urothelial carcinoma. This paper outlines the essential elements of TPS and the process that led to the formation and rationale of the reporting system. TPS Working Group, organized at the 2013 International Congress of Cytology, conceived a standardized platform on which to base cytologic interpretation of urine samples. The widespread dissemination of this approach to cytologic examination and reporting of urologic samples and the scheme's universal acceptance by pathologists and urologists is critical for its success. For urologists, understanding the diagnostic criteria, their clinical implications, and limitations of TPS is essential if they are to utilize urine cytology and noninvasive ancillary tests in a thoughtful and practical manner. This is the first international/inclusive attempt at standardizing urinary cytology. The success of TPS will depend on the pathology and urology communities working collectively to improve this seminal paradigm shift, and optimize the impact on patient care.

Space Shuttle Orbiter-Illustration

NASA Technical Reports Server (NTRS)

2001-01-01

This illustration is an orbiter cutaway view with callouts. The orbiter is both the brains and heart of the Space Transportation System (STS). About the same size and weight as a DC-9 aircraft, the orbiter contains the pressurized crew compartment (which can normally carry up to seven crew members), the huge cargo bay, and the three main engines mounted on its aft end. There are three levels to the crew cabin. Uppermost is the flight deck where the commander and the pilot control the mission. The middeck is where the gallery, toilet, sleep stations, and storage and experiment lockers are found for the basic needs of weightless daily living. Also located in the middeck is the airlock hatch into the cargo bay and space beyond. It is through this hatch and airlock that astronauts go to don their spacesuits and marned maneuvering units in preparation for extravehicular activities, more popularly known as spacewalks. The Space Shuttle's cargo bay is adaptable to hundreds of tasks. Large enough to accommodate a tour bus (60 x 15 feet or 18.3 x 4.6 meters), the cargo bay carries satellites, spacecraft, and spacelab scientific laboratories to and from Earth orbit. It is also a work station for astronauts to repair satellites, a foundation from which to erect space structures, and a hold for retrieved satellites to be returned to Earth. Thermal tile insulation and blankets (also known as the thermal protection system or TPS) cover the underbelly, bottom of the wings, and other heat-bearing surfaces of the orbiter to protect it during its fiery reentry into the Earth's atmosphere. The Shuttle's 24,000 individual tiles are made primarily of pure-sand silicate fibers, mixed with a ceramic binder. The solid rocket boosters (SRB's) are designed as an in-house Marshall Space Flight Center project, with United Space Boosters as the assembly and refurbishment contractor. The solid rocket motor (SRM) is provided by the Morton Thiokol Corporation.

Space Shuttle Projects

NASA Image and Video Library

2001-01-01

This illustration is an orbiter cutaway view with callouts. The orbiter is both the brains and heart of the Space Transportation System (STS). About the same size and weight as a DC-9 aircraft, the orbiter contains the pressurized crew compartment (which can normally carry up to seven crew members), the huge cargo bay, and the three main engines mounted on its aft end. There are three levels to the crew cabin. Uppermost is the flight deck where the commander and the pilot control the mission. The middeck is where the gallery, toilet, sleep stations, and storage and experiment lockers are found for the basic needs of weightless daily living. Also located in the middeck is the airlock hatch into the cargo bay and space beyond. It is through this hatch and airlock that astronauts go to don their spacesuits and marned maneuvering units in preparation for extravehicular activities, more popularly known as spacewalks. The Space Shuttle's cargo bay is adaptable to hundreds of tasks. Large enough to accommodate a tour bus (60 x 15 feet or 18.3 x 4.6 meters), the cargo bay carries satellites, spacecraft, and spacelab scientific laboratories to and from Earth orbit. It is also a work station for astronauts to repair satellites, a foundation from which to erect space structures, and a hold for retrieved satellites to be returned to Earth. Thermal tile insulation and blankets (also known as the thermal protection system or TPS) cover the underbelly, bottom of the wings, and other heat-bearing surfaces of the orbiter to protect it during its fiery reentry into the Earth's atmosphere. The Shuttle's 24,000 individual tiles are made primarily of pure-sand silicate fibers, mixed with a ceramic binder. The solid rocket boosters (SRB's) are designed as an in-house Marshall Space Flight Center project, with United Space Boosters as the assembly and refurbishment contractor. The solid rocket motor (SRM) is provided by the Morton Thiokol Corporation.

Biodegradation of sulfamethoxazole photo-transformation products in a water/sediment test.

PubMed

Su, Tong; Deng, Huiping; Benskin, Jonathan P; Radke, Michael

2016-04-01

Occurrence of the antibiotic sulfamethoxazole (SMX) in the aquatic environment is of concern due to its potential to induce antibiotic resistance in pathogenic bacteria. While degradation of SMX can occur by numerous processes, the environmental fate of its transformation products (TPs) remains poorly understood. In the present work, biodegradation of SMX photo-TPs was investigated in a water/sediment system. Photo-TPs were produced by exposing SMX to artificial sunlight for 48 h. The resulting mixture of 8 photo-TPs was characterized using a combination of ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry and tandem mass spectrometry, and then used in biodegradation experiments. Significant differences in transformation among SMX photo-TPs were observed in the water/sediment system, with four photo-TPs displaying evidence of biodegradation (dissipation half-lives [DT50] of 39.7 d for 3-amino-5-methylisoxazole, 12.7 d for 4-nitro-sulfamethxoazole, 7.6 d for an SMX isomer and 2.4 d for [C10H13N3O4S]), two displaying primarily abiotic degradation (DT50 of 31 d for sulfanilic acid and 74.9 d for 5-methylisoxazol-3-yl-sulfamate), and two photo-TPs behaving largely recalcitrantly. Remarkably, TPs previously reported to be photo-stable also were persistent in biodegradation experiments. The most surprising observation was an increase in SMX concentrations when the irradiated solution was incubated, which we attribute to back-transformation of certain photo-TPs by sediment bacteria (85% from 4-nitro-sulfamethoxazole). This process could contribute to exposure to SMX in the aquatic environment that is higher than one would expect based on the fate of SMX alone. The results highlight the importance of considering TPs along with their parent compounds when characterizing environmental risks of emerging contaminants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Design, fabrication, and tests of a metallic shell tile thermal protection system for space transportation

NASA Technical Reports Server (NTRS)

Macconochie, Ian O.; Kelly, H. Neale

1989-01-01

A thermal protection tile for earth-to-orbit transports is described. The tiles consist of a rigid external shell filled with a flexible insulation. The tiles tend to be thicker than the current Shuttle rigidized silica tiles for the same entry heat load but are projected to be more durable and lighter. The tiles were thermally tested for several simulated entry trajectories.

Accuracy Evaluation of Oncentra™ TPS in HDR Brachytherapy of Nasopharynx Cancer Using EGSnrc Monte Carlo Code.

PubMed

Hadad, K; Zohrevand, M; Faghihi, R; Sedighi Pashaki, A

2015-03-01

HDR brachytherapy is one of the commonest methods of nasopharyngeal cancer treatment. In this method, depending on how advanced one tumor is, 2 to 6 Gy dose as intracavitary brachytherapy is prescribed. Due to high dose rate and tumor location, accuracy evaluation of treatment planning system (TPS) is particularly important. Common methods used in TPS dosimetry are based on computations in a homogeneous phantom. Heterogeneous phantoms, especially patient-specific voxel phantoms can increase dosimetric accuracy. In this study, using CT images taken from a patient and ctcreate-which is a part of the DOSXYZnrc computational code, patient-specific phantom was made. Dose distribution was plotted by DOSXYZnrc and compared with TPS one. Also, by extracting the voxels absorbed dose in treatment volume, dose-volume histograms (DVH) was plotted and compared with Oncentra™ TPS DVHs. The results from calculations were compared with data from Oncentra™ treatment planning system and it was observed that TPS calculation predicts lower dose in areas near the source, and higher dose in areas far from the source relative to MC code. Absorbed dose values in the voxels also showed that TPS reports D90 value is 40% higher than the Monte Carlo method. Today, most treatment planning systems use TG-43 protocol. This protocol may results in errors such as neglecting tissue heterogeneity, scattered radiation as well as applicator attenuation. Due to these errors, AAPM emphasized departing from TG-43 protocol and approaching new brachytherapy protocol TG-186 in which patient-specific phantom is used and heterogeneities are affected in dosimetry.

Accuracy Evaluation of Oncentra™ TPS in HDR Brachytherapy of Nasopharynx Cancer Using EGSnrc Monte Carlo Code

PubMed Central

Hadad, K.; Zohrevand, M.; Faghihi, R.; Sedighi Pashaki, A.

2015-01-01

Background HDR brachytherapy is one of the commonest methods of nasopharyngeal cancer treatment. In this method, depending on how advanced one tumor is, 2 to 6 Gy dose as intracavitary brachytherapy is prescribed. Due to high dose rate and tumor location, accuracy evaluation of treatment planning system (TPS) is particularly important. Common methods used in TPS dosimetry are based on computations in a homogeneous phantom. Heterogeneous phantoms, especially patient-specific voxel phantoms can increase dosimetric accuracy. Materials and Methods In this study, using CT images taken from a patient and ctcreate-which is a part of the DOSXYZnrc computational code, patient-specific phantom was made. Dose distribution was plotted by DOSXYZnrc and compared with TPS one. Also, by extracting the voxels absorbed dose in treatment volume, dose-volume histograms (DVH) was plotted and compared with Oncentra™ TPS DVHs. Results The results from calculations were compared with data from Oncentra™ treatment planning system and it was observed that TPS calculation predicts lower dose in areas near the source, and higher dose in areas far from the source relative to MC code. Absorbed dose values in the voxels also showed that TPS reports D90 value is 40% higher than the Monte Carlo method. Conclusion Today, most treatment planning systems use TG-43 protocol. This protocol may results in errors such as neglecting tissue heterogeneity, scattered radiation as well as applicator attenuation. Due to these errors, AAPM emphasized departing from TG-43 protocol and approaching new brachytherapy protocol TG-186 in which patient-specific phantom is used and heterogeneities are affected in dosimetry. PMID:25973408

KSC-05pd2515

NASA Image and Video Library

2005-11-19

KENNEDY SPACE CENTER, FLA. - One of the blanket sewing machines used on Thermal Protection System materials has been returned to the TPS facility. It was moved to the RLV Hangar at NASA Kennedy Space Center after the 2004 hurricanes damaged the upper floor, where soft material was processed, of the TPS facility. While the TPS facility was being repaired, normal work activity was done in the hangar.

International Space Station (ISS) Soyuz Vehicle Descent Module Evaluation of Thermal Protection System (TPS) Penetration Characteristics

NASA Technical Reports Server (NTRS)

Davis, Bruce A.; Christiansen, Eric L.; Lear, Dana M.; Prior, Tom

2013-01-01

The descent module (DM) of the ISS Soyuz vehicle is covered by thermal protection system (TPS) materials that provide protection from heating conditions experienced during reentry. Damage and penetration of these materials by micrometeoroid and orbital debris (MMOD) impacts could result in loss of vehicle during return phases of the mission. The descent module heat shield has relatively thick TPS and is protected by the instrument-service module. The TPS materials on the conical sides of the descent module (referred to as backshell in this test plan) are exposed to more MMOD impacts and are relatively thin compared to the heat shield. This test program provides hypervelocity impact (HVI) data on materials similar in composition and density to the Soyuz TPS on the backshell of the vehicle. Data from this test program was used to update ballistic limit equations used in Soyuz TPS penetration risk assessments. The impact testing was coordinated by the NASA Johnson Space Center (JSC) Hypervelocity Impact Technology (HVIT) Group [1] in Houston, Texas. The HVI testing was conducted at the NASA-JSC White Sands Hypervelocity Impact Test Facility (WSTF) at Las Cruces, New Mexico. Figure

A Global User-Driven Model for Tile Prefetching in Web Geographical Information Systems

PubMed Central

Pan, Shaoming; Chong, Yanwen; Zhang, Hang; Tan, Xicheng

2017-01-01

A web geographical information system is a typical service-intensive application. Tile prefetching and cache replacement can improve cache hit ratios by proactively fetching tiles from storage and replacing the appropriate tiles from the high-speed cache buffer without waiting for a client’s requests, which reduces disk latency and improves system access performance. Most popular prefetching strategies consider only the relative tile popularities to predict which tile should be prefetched or consider only a single individual user's access behavior to determine which neighbor tiles need to be prefetched. Some studies show that comprehensively considering all users’ access behaviors and all tiles’ relationships in the prediction process can achieve more significant improvements. Thus, this work proposes a new global user-driven model for tile prefetching and cache replacement. First, based on all users’ access behaviors, a type of expression method for tile correlation is designed and implemented. Then, a conditional prefetching probability can be computed based on the proposed correlation expression mode. Thus, some tiles to be prefetched can be found by computing and comparing the conditional prefetching probability from the uncached tiles set and, similarly, some replacement tiles can be found in the cache buffer according to multi-step prefetching. Finally, some experiments are provided comparing the proposed model with other global user-driven models, other single user-driven models, and other client-side prefetching strategies. The results show that the proposed model can achieve a prefetching hit rate in approximately 10.6% ~ 110.5% higher than the compared methods. PMID:28085937

Mashup Scheme Design of Map Tiles Using Lightweight Open Source Webgis Platform

NASA Astrophysics Data System (ADS)

Hu, T.; Fan, J.; He, H.; Qin, L.; Li, G.

2018-04-01

To address the difficulty involved when using existing commercial Geographic Information System platforms to integrate multi-source image data fusion, this research proposes the loading of multi-source local tile data based on CesiumJS and examines the tile data organization mechanisms and spatial reference differences of the CesiumJS platform, as well as various tile data sources, such as Google maps, Map World, and Bing maps. Two types of tile data loading schemes have been designed for the mashup of tiles, the single data source loading scheme and the multi-data source loading scheme. The multi-sources of digital map tiles used in this paper cover two different but mainstream spatial references, the WGS84 coordinate system and the Web Mercator coordinate system. According to the experimental results, the single data source loading scheme and the multi-data source loading scheme with the same spatial coordinate system showed favorable visualization effects; however, the multi-data source loading scheme was prone to lead to tile image deformation when loading multi-source tile data with different spatial references. The resulting method provides a low cost and highly flexible solution for small and medium-scale GIS programs and has a certain potential for practical application values. The problem of deformation during the transition of different spatial references is an important topic for further research.

Remtech SSME nozzle design TPS

NASA Technical Reports Server (NTRS)

Bancroft, Steven A.; Engel, Carl D.; Pond, John E.

1990-01-01

Thermal damage to the Space Shuttle Main Engine (SSME) aft manifold Thermal Protection System (TPS) has been observed for flights STS-8 through STS-13. This damaged area is located on the ME2 and ME3 and extends over a region of approximately one square foot. Total failure or burn-through of the TPS could lead to severe thermal damage of the SSME manifold and loss of an engine nozzle necessitating nozzle replacement causing significant schedule delays and cost increases. Thermal damage to the manifold can be defined as a situation where the manifold temperature becomes greater than 1300 F; thereby causing loss of heat treatment in the nozzle. Results of Orbiter/nozzle wind tunnel tests and Hot Gas Facility tests of the TPS are presented. Aerothermal and thermal analysis models for the SSME aft manifold are discussed along with the flight predictions, design trajectory and design environment. Finally, the TPS design concept and TPS thermal response are addressed.

The Effects of Foam Thermal Protection System on the Damage Tolerance Characteristics of Composite Sandwich Structures for Launch Vehicles

NASA Technical Reports Server (NTRS)

Nettles, A. T.; Hodge, A. J.; Jackson, J. R.

2011-01-01

For any structure composed of laminated composite materials, impact damage is one of the greatest risks and therefore most widely tested responses. Typically, impact damage testing and analysis assumes that a solid object comes into contact with the bare surface of the laminate (the outer ply). However, most launch vehicle structures will have a thermal protection system (TPS) covering the structure for the majority of its life. Thus, the impact response of the material with the TPS covering is the impact scenario of interest. In this study, laminates representative of the composite interstage structure for the Ares I launch vehicle were impact tested with and without the planned TPS covering, which consists of polyurethane foam. Response variables examined include maximum load of impact, damage size as detected by nondestructive evaluation techniques, and damage morphology and compression after impact strength. Results show that there is little difference between TPS covered and bare specimens, except the residual strength data is higher for TPS covered specimens.

Power Transfer Efficiency of Mutually Coupled Coils in an Aluminum AUV Hull

DTIC Science & Technology

2013-12-01

the tiles are made from a nickel -zinc material, a reasonable value is 20.0.r  38 Figure 24. Photograph of the ferrite board behind the...results were then compared to three sets of measured efficiency data: an IPT system without ferrite tiles; an IPT system with the receiving coil...attached to ferrite tiles; and an IPT system with the receiving coil/ ferrite tile combination placed inside an aluminum AUV hull. Efficiency was poor, less

Applying the Paris System for Reporting Urine Cytology Increases the Rate of Atypical Urothelial Cells in Benign Cases: A Need for Patient Management Recommendations.

PubMed

Granados, Rosario; Duarte, Joanny A; Corrales, Teresa; Camarmo, Encarnación; Bajo, Paloma

2017-01-01

The Paris System (TPS) for reporting urinary cytology attempts to unify the terminology in this field. To analyze the impact of adopting TPS by measuring nomenclature agreement and cytohistological correlation. Voided urine liquid-based cytology samples corresponding to 149 biopsy-proven cases (76 high-grade carcinomas, 40 low-grade carcinomas, and 33 benign lesions), were reclassified by the same pathologist using TPS. Diagnostic agreement and sensitivity for both nomenclature systems was measured. When using TPS, the rate of atypical samples increased 8 times (from 3 to 24.2%) in benign cases, 10 times (from 2.5 to 25%) in low-grade carcinomas, and 2.4 times (from 6.6 to 15.8%) in high-grade carcinomas. The false-positive rate (abnormal cytology in negative or low-grade carcinoma cases) increased from 11 to 34.2%. Sensitivity was higher (63 vs. 49%) with TPS at the expense of a lower specificity (73 vs. 91%). The agreement between both nomenclatures was moderate for negative and high-grade carcinoma cases (k = 0.42 and 0.56, respectively) and weak for low-grade tumors (k = 0.35). Adopting TPS for reporting urine cytology results in a considerable increase in atypical diagnoses, improving sensitivity but lowering specificity. Appropriate management recommendations for patients with an atypical cytological diagnosis are required. © 2016 S. Karger AG, Basel.

Study of dose calculation on breast brachytherapy using prism TPS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fendriani, Yoza; Haryanto, Freddy

2015-09-30

PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the firstmore » case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm{sup 3}. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm{sup 3}. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy.« less

Thermal Protection for Mars Sample Return Earth Entry Vehicle: A Grand Challenge for Design Methodology and Reliability Verification

NASA Technical Reports Server (NTRS)

Venkatapathy, Ethiraj; Gage, Peter; Wright, Michael J.

2017-01-01

Mars Sample Return is our Grand Challenge for the coming decade. TPS (Thermal Protection System) nominal performance is not the key challenge. The main difficulty for designers is the need to verify unprecedented reliability for the entry system: current guidelines for prevention of backward contamination require that the probability of spores larger than 1 micron diameter escaping into the Earth environment be lower than 1 million for the entire system, and the allocation to TPS would be more stringent than that. For reference, the reliability allocation for Orion TPS is closer to 11000, and the demonstrated reliability for previous human Earth return systems was closer to 1100. Improving reliability by more than 3 orders of magnitude is a grand challenge indeed. The TPS community must embrace the possibility of new architectures that are focused on reliability above thermal performance and mass efficiency. MSR (Mars Sample Return) EEV (Earth Entry Vehicle) will be hit with MMOD (Micrometeoroid and Orbital Debris) prior to reentry. A chute-less aero-shell design which allows for self-righting shape was baselined in prior MSR studies, with the assumption that a passive system will maximize EEV robustness. Hence the aero-shell along with the TPS has to take ground impact and not break apart. System verification will require testing to establish ablative performance and thermal failure but also testing of damage from MMOD, and structural performance at ground impact. Mission requirements will demand analysis, testing and verification that are focused on establishing reliability of the design. In this proposed talk, we will focus on the grand challenge of MSR EEV TPS and the need for innovative approaches to address challenges in modeling, testing, manufacturing and verification.

Filler bar heating due to stepped tiles in the shuttle orbiter thermal protection system

NASA Technical Reports Server (NTRS)

Petley, D. H.; Smith, D. M.; Edwards, C. L. W.; Patten, A. B.; Hamilton, H. H., II

1983-01-01

An analytical study was performed to investigate the excessive heating in the tile to tile gaps of the Shuttle Orbiter Thermal Protection System due to stepped tiles. The excessive heating was evidence by visible discoloration and charring of the filler bar and strain isolation pad that is used in the attachment of tiles to the aluminum substrate. Two tile locations on the Shuttle orbiter were considered, one on the lower surface of the fuselage and one on the lower surface of the wing. The gap heating analysis involved the calculation of external and internal gas pressures and temperatures, internal mass flow rates, and the transient thermal response of the thermal protection system. The results of the analysis are presented for the fuselage and wing location for several step heights. The results of a study to determine the effectiveness of a half height ceramic fiber gap filler in preventing hot gas flow in the tile gaps are also presented.

Collaborative Analysis Tool for Thermal Protection Systems for Single Stage to Orbit Launch Vehicles

NASA Technical Reports Server (NTRS)

Alexander, Reginald Andrew; Stanley, Thomas Troy

1999-01-01

Presented is a design tool and process that connects several disciplines which are needed in the complex and integrated design of high performance reusable single stage to orbit (SSTO) vehicles. Every system is linked to every other system and in the case of SSTO vehicles with air breathing propulsion, which is currently being studied by the National Aeronautics and Space Administration (NASA); the thermal protection system (TPS) is linked directly to almost every major system. The propulsion system pushes the vehicle to velocities on the order of 15 times the speed of sound in the atmosphere before pulling up to go to orbit which results high temperatures on the external surfaces of the vehicle. Thermal protection systems to maintain the structural integrity of the vehicle must be able to mitigate the heat transfer to the structure and be lightweight. Herein lies the interdependency, in that as the vehicle's speed increases, the TPS requirements are increased. And as TPS masses increase the effect on the propulsion system and all other systems is compounded. To adequately determine insulation masses for a vehicle such as the one described above, the aeroheating loads must be calculated and the TPS thicknesses must be calculated for the entire vehicle. To accomplish this an ascent or reentry trajectory is obtained using the computer code Program to Optimize Simulated Trajectories (POST). The trajectory is then used to calculate the convective heat rates on several locations on the vehicles using the Miniature Version of the JA70 Aerodynamic Heating Computer Program (MINIVER). Once the heat rates are defined for each body point on the vehicle, then insulation thickness that are required to maintain the vehicle within structural limits are calculated using Systems Improved Numerical Differencing Analyzer (SINDA) models. If the TPS masses are too heavy for the performance of the vehicle the process may be repeated altering the trajectory or some other input to reduce the TPS mass.

SU-D-BRD-01: Cloud-Based Radiation Treatment Planning: Performance Evaluation of Dose Calculation and Plan Optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Na, Y; Kapp, D; Kim, Y

2014-06-01

Purpose: To report the first experience on the development of a cloud-based treatment planning system and investigate the performance improvement of dose calculation and treatment plan optimization of the cloud computing platform. Methods: A cloud computing-based radiation treatment planning system (cc-TPS) was developed for clinical treatment planning. Three de-identified clinical head and neck, lung, and prostate cases were used to evaluate the cloud computing platform. The de-identified clinical data were encrypted with 256-bit Advanced Encryption Standard (AES) algorithm. VMAT and IMRT plans were generated for the three de-identified clinical cases to determine the quality of the treatment plans and computationalmore » efficiency. All plans generated from the cc-TPS were compared to those obtained with the PC-based TPS (pc-TPS). The performance evaluation of the cc-TPS was quantified as the speedup factors for Monte Carlo (MC) dose calculations and large-scale plan optimizations, as well as the performance ratios (PRs) of the amount of performance improvement compared to the pc-TPS. Results: Speedup factors were improved up to 14.0-fold dependent on the clinical cases and plan types. The computation times for VMAT and IMRT plans with the cc-TPS were reduced by 91.1% and 89.4%, respectively, on average of the clinical cases compared to those with pc-TPS. The PRs were mostly better for VMAT plans (1.0 ≤ PRs ≤ 10.6 for the head and neck case, 1.2 ≤ PRs ≤ 13.3 for lung case, and 1.0 ≤ PRs ≤ 10.3 for prostate cancer cases) than for IMRT plans. The isodose curves of plans on both cc-TPS and pc-TPS were identical for each of the clinical cases. Conclusion: A cloud-based treatment planning has been setup and our results demonstrate the computation efficiency of treatment planning with the cc-TPS can be dramatically improved while maintaining the same plan quality to that obtained with the pc-TPS. This work was supported in part by the National Cancer Institute (1R01 CA133474) and by Leading Foreign Research Institute Recruitment Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (MSIP) (Grant No.2009-00420)« less

The SHEFEX II Thermal Protection System

NASA Astrophysics Data System (ADS)

Bohrk, H.; Elsaber, H.; Weihs, H.

2011-05-01

The SHEFEXII payload tip is ready for flight. Within a period of three years, the experiment has been designed, laid out, parts have been manufactured, mounted and instrumented for the upcoming flight in autumn 2011. The present paper gives an overview over the thermal protection system (TPS) of the SHEFEX II vehicle including the TPS-material, the overall TPS-setup, and detailed informations on the faceted ther- mal protection including the gap seal, the sharp leading edge, the transpiration-cooling experiment AKTIV, and the aerodynamic control surfaces, i.e. canards.

Thermal Protection Systems: Past, Present and Future

NASA Technical Reports Server (NTRS)

Johnson, Sylvia M.

2015-01-01

Thermal protection materials and systems (TPS) have been critical to fulfilling humankinds desire to explore space. Composite and ceramic materials have enabled the early missions to orbit, the moon, the space station, Mars with robots, and sample return. Crewed missions to Mars are being considered, and this places even more demands on TPS materials. This talk will give some history on the materials used for earth and planetary entry and the demands placed upon such materials. TPS needs for future missions, especially to Mars, will be identified and potential solutions discussed.

Position Paper External Tank Thermal Protection System (TPS) Manually Sprayed fly-as-is Foam Certification

NASA Technical Reports Server (NTRS)

Stadler, John H.

2009-01-01

During manufacture of the existing External Tanks (ETs), the Thermal Protection System (TPS) foam manual spray application processes lacked the enhanced controls/procedures to ensure that defects produced were less than the critical size. Therefore the only remaining option to certify the "fly-as-is" foam is to verify ET120 tank hardware meets the new foam debris requirements. The ET project has undertaken a significant effort studying the existing "fly-as-is" TPS foam. This paper contains the findings of the study.

Automotive Insulation

NASA Technical Reports Server (NTRS)

1997-01-01

Under a Space Act Agreement between Boeing North America and BSR Products, Space Shuttle Thermal Protection System (TPS) materials are now used to insulate race cars. BSR has created special TPS blanket insulation kits for use on autos that take part in NASCAR events, and other race cars through its nationwide catalog distribution system. Temperatures inside a race car's cockpit can soar to a sweltering 140 to 160 degrees, with the extreme heat coming through the engine firewall, transmission tunnel, and floor. It is common for NASCAR drivers to endure blisters and burns due to the excessive heat. Tests on a car insulated with the TPS material showed a temperature drop of some 50 degrees in the driver's cockpit. BSR-TPS Products, Inc. now manufactures insulation kits for distribution to race car teams around the world.

Monitoring of Thermal Protection Systems Using Robust Self-Organizing Optical Fiber Sensing Networks

NASA Technical Reports Server (NTRS)

Richards, Lance

2013-01-01

The general aim of this work is to develop and demonstrate a prototype structural health monitoring system for thermal protection systems that incorporates piezoelectric acoustic emission (AE) sensors to detect the occurrence and location of damaging impacts, and an optical fiber Bragg grating (FBG) sensor network to evaluate the effect of detected damage on the thermal conductivity of the TPS material. Following detection of an impact, the TPS would be exposed to a heat source, possibly the sun, and the temperature distribution on the inner surface in the vicinity of the impact measured by the FBG network. A similar procedure could also be carried out as a screening test immediately prior to re-entry. The implications of any detected anomalies in the measured temperature distribution will be evaluated for their significance in relation to the performance of the TPS during re-entry. Such a robust TPS health monitoring system would ensure overall crew safety throughout the mission, especially during reentry

Integrative Advanced Oxidation and Biofiltration for Treating Pharmaceuticals in Wastewater.

PubMed

Lester, Yaal; Aga, Diana S; Love, Nancy G; Singh, Randolph R; Morrissey, Ian; Linden, Karl G

2016-11-01

  Advanced oxidation of active pharmaceutical ingredients (APIs) in wastewater produces transformation products (TPs) that are often more biodegradable than the parent compounds. Secondary effluent from a wastewater treatment plant was treated using UV-based advanced oxidation (LPUV/H2O2 and MPUV/NO3) followed by biological aerated filtration (BAF), and different APIs and their transformation products were monitored. The advanced oxidation processes degraded the APIs by 55-87% (LPUV/H2O2) and 58-95% (MPUV/NO3), while minor loss of APIs was achieved in the downstream BAF system. Eleven TPs were detected following oxidation of carbamazepine (5) and iopromide (6); three key TPs were biodegraded in the BAF system. The other TPs remained relatively constant in the BAF. The decrease in UV absorbance (UVA254) of the effluent in the BAF system was linearly correlated to the degradation of the APIs (for the MPUV/NO3-BAF), and can be applied to monitor the biotransformation of APIs in biological-based systems.

Modal analysis and dynamic stresses for acoustically excited Shuttle insulation tiles

NASA Technical Reports Server (NTRS)

Ojalvo, I. U.; Ogilvie, P. I.

1976-01-01

The thermal protection system of the Space Shuttle consists of thousands of separate insulation tiles, of varying thicknesses, bonded to the orbiter's surface through a soft strain-isolation pad which is bonded, in turn, to the vehicle's stiffened metallic skin. A modal procedure for obtaining the acoustically induced RMS stress in these comparatively thick tiles is described. The modes employed are generated by a previously developed iterative procedure which converges rapidly for the combined system of tiles and primary structure considered. Each tile is idealized by several hundred three-dimensional finite elements and all tiles on a given panel interact dynamically. Acoustic response results from the present analyses are presented. Comparisons with other analytical results and measured modal data for a typical Shuttle panel, both with and without tiles, are made, and the agreement is good.

NASA Crew Exploration Vehicle, Thermal Protection System, Lessons Learned

NASA Technical Reports Server (NTRS)

Venkatapathy, Ethiraj; Reuther, James

2008-01-01

The Orion (CEV) thermal protection system (TPS) advanced development project (ADP) was initiated in late 2006 to reduce developmental risk by significant investment in multiple heat shield architectural solutions that can meet the needs both the Low Earth orbit (LEO) and Lunar return missions. At the same time, the CEV TPS ADP was also charged with developing a preliminary design for the heat shield to meet the PDR requirement and at the time of the PDR, transfer the design to Lockheed- Martin, the prime contractor. We reported on the developmental activities of the first 18 months at the IPPW5 in Bordeaux, France, last summer. In June 08, at the time of the IPPW6, the CEV TPS ADP would have nearly completed the preparation for the Orion PDR and would be close to the original three-year mark. We plan to report on the progress at the Atlanta workshop. In the past year, Orion TPS ADP investment in TPS Technology, especially in PICA ablative Heat-shield design, development, testing and engineering (DDTE) has paid off in enabling MSL mission to switch from SLA 561 V heat shield to PICA heat shield. CEV TPS ADP considered SLA 561 V as a candidate for LEO missions and our testing identified failure modes in SLA and as a result, we dropped SLA for further evaluation. This close synergy between two projects is a highly visible example of how investment in technology areas can and does benefit multiple missions. In addition, CEV TPS ADP has been able to revive the Apollo ablative system namely AVCOAT honeycomb architecture as an alternate to the baseline PICA architecture and we plan to report the progress we have made in AVCOAT. CEV TPS ADP has invested considerable resources in developing analytical models for PICA and AVCOAT, material property measurements that is essential to the design of the heat-shield, in arcjet testing, in understanding the differences between different arc jet facilities, namely NASA Ames, NASA JSC and Air Force's AEDC, and in Non-Destructive Evaluation (NDE), and in integration of and manufacturing heat shield as a system. The capabilities of the two heat shield systems including failure modes via testing and analysis, once established, can serve the Probe Community and future mission designers to inner and outer planetary exploration very well. For example, missions to Venus, Mars and Titan can use either one of the system by selecting the mission design parameters that utilizes the full characteristics of these system to make use of system efficiency that will result in reduced heat shield mass, system robustness that will enhance mission success and cost. We plan to present significant progresses of the past three years and highlight the significant contributions CEV TPS ADP Project has made to advance the state of the art in Thermal Protection System technology that has and will continue to benefit future entry probe missions.

Thermal Protection System Mass Estimating Relationships for Blunt-Body, Earth Entry Spacecraft

NASA Technical Reports Server (NTRS)

Sepka, Steven A.; Samareh, Jamshid A.

2015-01-01

System analysis and design of any entry system must balance the level fidelity for each discipline against the project timeline. One way to inject high fidelity analysis earlier in the design effort is to develop surrogate models for the high-fidelity disciplines. Surrogate models for the Thermal Protection System (TPS) are formulated as Mass Estimating Relationships (MERs). The TPS MERs are presented that predict the amount of TPS necessary for safe Earth entry for blunt-body spacecraft using simple correlations that closely match estimates from NASA's high-fidelity ablation modeling tool, the Fully Implicit Ablation and Thermal Analysis Program (FIAT). These MERs provide a first order estimate for rapid feasibility studies. There are 840 different trajectories considered in this study, and each TPS MER has a peak heating limit. MERs for the vehicle forebody include the ablators Phenolic Impregnated Carbon Ablator (PICA) and Carbon Phenolic atop Advanced Carbon-Carbon. For the aftbody, the materials are Silicone Impregnated Reusable Ceramic Ablator (SIRCA), Acusil II, SLA-561V, and LI-900. The MERs are accurate to within 14% (at one standard deviation) of FIAT prediction, and the most any MER under predicts FIAT TPS thickness is 18.7%. This work focuses on the development of these MERs, the resulting equations, model limitations, and model accuracy.

CFD Script for Rapid TPS Damage Assessment

NASA Technical Reports Server (NTRS)

McCloud, Peter

2013-01-01

This grid generation script creates unstructured CFD grids for rapid thermal protection system (TPS) damage aeroheating assessments. The existing manual solution is cumbersome, open to errors, and slow. The invention takes a large-scale geometry grid and its large-scale CFD solution, and creates a unstructured patch grid that models the TPS damage. The flow field boundary condition for the patch grid is then interpolated from the large-scale CFD solution. It speeds up the generation of CFD grids and solutions in the modeling of TPS damages and their aeroheating assessment. This process was successfully utilized during STS-134.

Geometrical tile design for complex neighborhoods.

PubMed

Czeizler, Eugen; Kari, Lila

2009-01-01

Recent research has showed that tile systems are one of the most suitable theoretical frameworks for the spatial study and modeling of self-assembly processes, such as the formation of DNA and protein oligomeric structures. A Wang tile is a unit square, with glues on its edges, attaching to other tiles and forming larger and larger structures. Although quite intuitive, the idea of glues placed on the edges of a tile is not always natural for simulating the interactions occurring in some real systems. For example, when considering protein self-assembly, the shape of a protein is the main determinant of its functions and its interactions with other proteins. Our goal is to use geometric tiles, i.e., square tiles with geometrical protrusions on their edges, for simulating tiled paths (zippers) with complex neighborhoods, by ribbons of geometric tiles with simple, local neighborhoods. This paper is a step toward solving the general case of an arbitrary neighborhood, by proposing geometric tile designs that solve the case of a "tall" von Neumann neighborhood, the case of the f-shaped neighborhood, and the case of a 3 x 5 "filled" rectangular neighborhood. The techniques can be combined and generalized to solve the problem in the case of any neighborhood, centered at the tile of reference, and included in a 3 x (2k + 1) rectangle.

Post-Flight Assessment of Avcoat Thermal Protection System for the Exploration Flight Test-1

NASA Technical Reports Server (NTRS)

Bose, Deepak; Santos, Jose; Rodriguez, Erika; Mahzari, Milad; Remark, Brian; Muppidi, Suman

2016-01-01

On December 5, 2014 NASA conducted the first flight test of its next generation human-class Orion spacecraft. The flight was called the Exploration Flight Test -1 (EFT-1) which lasted for 4 hours and culminated into a re-entry trajectory at 9 km/s. This flight test of the 5-meter Orion Crew Module demonstrated various sub-systems including the Avcoat ablative thermal protection system (TPS) on the heat shield. The Avcoat TPS had been developed from the Apollo-era recipe with a few key modifications. The engineering for thermal sizing was supported by modeling, analysis, and ground tests in arc jet facilities. This paper will describe a postlfight analysis plan and present results from post-recovery inspections, data analysis from embedded sensors, TPS sample extraction and characterization in the laboratory. After the recovery of the vehicle, a full photographic survey and surface scans of the TPS were performed. The recovered vehicle showed physical evidence of flow disturbances, varying degrees of surface roughness, and excessive recession downstream of compression pads. The TPS recession was measured at more than 200 locations of interest on the Avcoat surface. The heat shield was then processed for sample extraction prior to TPS removal using the 7-Axis Milling machine at Marshall Space Flight Center. Around 182 rectangular TPS samples were extracted for subsequent analysis and investigation. The final paper will also present results of sample analysis. The planned investigation includes sidewall imaging, followed by image analysis to characterize TPS response by quantifying different layers in the char and pyrolysis zones. A full postmortem of the instrumentation and sensor ports will also be performed to confirm no adverse effects due to the sensors themselves. A subset of the samples will undergo structural testing and perform detailed characterization of any cracks and integrity of gore seams. Finally, the material will be characterized with layer-by-layer density measurements and SEM investigations to evaluate material morphology at microstructural level including identification of elements and compounds.

Water table management reduces tile nitrate loss in continuous corn and in a soybean-corn rotation.

PubMed

Drury, C F; Tan, C S; Gaynor, J D; Reynolds, W D; Welacky, T W; Oloya, T O

2001-10-25

Water table management systems can be designed to alleviate soil water excesses and deficits, as well as reduce nitrate leaching losses in tile discharge. With this in mind, a standard tile drainage (DR) system was compared over 8 years (1991 to 1999) to a controlled tile drainage/subirrigation (CDS) system on a low-slope (0.05 to 0.1%) Brookston clay loam soil (Typic Argiaquoll) in southwestern Ontario, Canada. In the CDS system, tile discharge was controlled to prevent excessive drainage, and water was pumped back up the tile lines (subirrigation) to replenish the crop root zone during water deficit periods. In the first phase of the study (1991 to 1994), continuous corn (Zea mays, L.) was grown with annual nitrogen (N) fertilizer inputs as per local soil test recommendations. In the second phase (1995 to 1999), a soybean (Glycine max L., Merr.)-corn rotation was used with N fertilizer added only during the two corn years. In Phase 1 when continuous corn was grown, CDS reduced total tile discharge by 26% and total nitrate loss in tile discharge by 55%, compared to DR. In addition, the 4-year flow weighted mean (FWM) nitrate concentration in tile discharge exceeded the Canadian drinking water guideline (10 mg N l(-1)) under DR (11.4 mg N l(-1)), but not under CDS (7.0 mg N l(-1)). In Phase 2 during the soybean-corn rotation, CDS reduced total tile discharge by 38% and total nitrate loss in tile discharge by 66%, relative to DR. The 4-year FWM nitrate concentration during Phase 2 in tile discharge was below the drinking water guideline for both DR (7.3 mg N l(-1)) and CDS (4.0 mg N l(-1)). During both phases of the experiment, the CDS treatment caused only minor increases in nitrate loss in surface runoff relative to DR. Hence CDS decreased FWM nitrate concentrations, total drainage water loss, and total nitrate loss in tile discharge relative to DR. In addition, soybean-corn rotation reduced FWM nitrate concentrations and total nitrate loss in tile discharge relative to continuous corn. CDS and crop rotations with reduced N fertilizer inputs can thus improve the quality of tile discharge water substantially.

KSC-04pd1852

NASA Image and Video Library

2004-09-18

KENNEDY SPACE CENTER, FLA. - Looking at damage on the second floor of the hurricane-ravaged Thermal Protection System Facility (TPSF) are (from left) Kevin Harrington, manager of Soft Goods Production, TPSF ; Martin Wilson, manager of Thermal Protection System operations for USA; Scott Kerr, KSC director of Spaceport Services; and James Kennedy, Center director. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof during Hurricane Frances, which blew across Central Florida Sept. 4-5. Undamaged equipment was removed from the TPSF and stored in the RLV hangar. NASA Administrator Sean O’Keefe and NASA Associate Administrator of Space Operations Mission Directorate William Readdy are visiting KSC to survey the damage sustained by KSC facilities from the hurricane. The Labor Day storm also caused significant damage to the Vehicle Assembly Building and Processing Control Center. Additionally, the Operations and Checkout Building, Vertical Processing Facility, Hangar AE, Hangar S and Hangar AF Small Parts Facility each received substantial damage. However, well-protected and unharmed were NASA’s three Space Shuttle orbiters - Discovery, Atlantis and Endeavour - along with the Shuttle launch pads, all of the critical flight hardware for the orbiters and the International Space Station, and NASA’s Swift spacecraft that is awaiting launch in October.

Functional characterization of nine Norway Spruce TPS genes and evolution of gymnosperm terpene synthases of the TPS-d subfamily.

PubMed

Martin, Diane M; Fäldt, Jenny; Bohlmann, Jörg

2004-08-01

Constitutive and induced terpenoids are important defense compounds for many plants against potential herbivores and pathogens. In Norway spruce (Picea abies L. Karst), treatment with methyl jasmonate induces complex chemical and biochemical terpenoid defense responses associated with traumatic resin duct development in stems and volatile terpenoid emissions in needles. The cloning of (+)-3-carene synthase was the first step in characterizing this system at the molecular genetic level. Here we report the isolation and functional characterization of nine additional terpene synthase (TPS) cDNAs from Norway spruce. These cDNAs encode four monoterpene synthases, myrcene synthase, (-)-limonene synthase, (-)-alpha/beta-pinene synthase, and (-)-linalool synthase; three sesquiterpene synthases, longifolene synthase, E,E-alpha-farnesene synthase, and E-alpha-bisabolene synthase; and two diterpene synthases, isopimara-7,15-diene synthase and levopimaradiene/abietadiene synthase, each with a unique product profile. To our knowledge, genes encoding isopimara-7,15-diene synthase and longifolene synthase have not been previously described, and this linalool synthase is the first described from a gymnosperm. These functionally diverse TPS account for much of the structural diversity of constitutive and methyl jasmonate-induced terpenoids in foliage, xylem, bark, and volatile emissions from needles of Norway spruce. Phylogenetic analyses based on the inclusion of these TPS into the TPS-d subfamily revealed that functional specialization of conifer TPS occurred before speciation of Pinaceae. Furthermore, based on TPS enclaves created by distinct branching patterns, the TPS-d subfamily is divided into three groups according to sequence similarities and functional assessment. Similarities of TPS evolution in angiosperms and modeling of TPS protein structures are discussed.

Driving improvement in patient care: lessons from Toyota.

PubMed

Thompson, Debra N; Wolf, Gail A; Spear, Steven J

2003-11-01

Nurses today are attempting to do more with less while grappling with faulty error-prone systems that do not focus on patients at the point of care. This struggle occurs against a backdrop of rising national concern over the incidence of medical errors in healthcare. In an effort to create greater value with scarce resources and fix broken systems that compromise quality care, UPMC Health System is beginning to master and implement the Toyota Production System (TPS)--a method of managing people engaged in work that emphasizes frequent rapid problem solving and work redesign that has become the global archetype for productivity and performance. The authors discuss the rationale for applying TPS to healthcare and implementation of the system through the development of "learning unit" model lines and initial outcomes, such as dramatic reductions in the number of missing medications and thousands of hours and dollars saved as a result of TPS-driven changes. Tracking data further suggest that TPS, with sufficient staff preparation and involvement, has the potential for continuous, lasting, and accelerated improvement in patient care.

Extravehicular Activity Probabilistic Risk Assessment Overview for Thermal Protection System Repair on the Hubble Space Telescope Servicing Mission

NASA Technical Reports Server (NTRS)

Bigler, Mark; Canga, Michael A.; Duncan, Gary

2010-01-01

The Shuttle Program initiated an Extravehicular Activity (EVA) Probabilistic Risk Assessment (PRA) to assess the risks associated with performing a Shuttle Thermal Protection System (TPS) repair during the Space Transportation System (STS)-125 Hubble repair mission as part of risk trades between TPS repair and crew rescue.

STS-335 crew training, EVA TPS Overview with instructor John Ray

NASA Image and Video Library

2010-11-03

JSC2010-E-183521 (3 Nov. 2010) --- NASA astronaut Chris Ferguson, STS-135 commander, participates in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center. STS-135 is planned to be the final mission of the space shuttle program. Photo credit: NASA or National Aeronautics and Space Administration

Dosimetric accuracy of a treatment planning system for actively scanned proton beams and small target volumes: Monte Carlo and experimental validation

NASA Astrophysics Data System (ADS)

Magro, G.; Molinelli, S.; Mairani, A.; Mirandola, A.; Panizza, D.; Russo, S.; Ferrari, A.; Valvo, F.; Fossati, P.; Ciocca, M.

2015-09-01

This study was performed to evaluate the accuracy of a commercial treatment planning system (TPS), in optimising proton pencil beam dose distributions for small targets of different sizes (5-30 mm side) located at increasing depths in water. The TPS analytical algorithm was benchmarked against experimental data and the FLUKA Monte Carlo (MC) code, previously validated for the selected beam-line. We tested the Siemens syngo® TPS plan optimisation module for water cubes fixing the configurable parameters at clinical standards, with homogeneous target coverage to a 2 Gy (RBE) dose prescription as unique goal. Plans were delivered and the dose at each volume centre was measured in water with a calibrated PTW Advanced Markus® chamber. An EBT3® film was also positioned at the phantom entrance window for the acquisition of 2D dose maps. Discrepancies between TPS calculated and MC simulated values were mainly due to the different lateral spread modeling and resulted in being related to the field-to-spot size ratio. The accuracy of the TPS was proved to be clinically acceptable in all cases but very small and shallow volumes. In this contest, the use of MC to validate TPS results proved to be a reliable procedure for pre-treatment plan verification.

Dosimetric accuracy of a treatment planning system for actively scanned proton beams and small target volumes: Monte Carlo and experimental validation.

PubMed

Magro, G; Molinelli, S; Mairani, A; Mirandola, A; Panizza, D; Russo, S; Ferrari, A; Valvo, F; Fossati, P; Ciocca, M

2015-09-07

This study was performed to evaluate the accuracy of a commercial treatment planning system (TPS), in optimising proton pencil beam dose distributions for small targets of different sizes (5-30 mm side) located at increasing depths in water. The TPS analytical algorithm was benchmarked against experimental data and the FLUKA Monte Carlo (MC) code, previously validated for the selected beam-line. We tested the Siemens syngo(®) TPS plan optimisation module for water cubes fixing the configurable parameters at clinical standards, with homogeneous target coverage to a 2 Gy (RBE) dose prescription as unique goal. Plans were delivered and the dose at each volume centre was measured in water with a calibrated PTW Advanced Markus(®) chamber. An EBT3(®) film was also positioned at the phantom entrance window for the acquisition of 2D dose maps. Discrepancies between TPS calculated and MC simulated values were mainly due to the different lateral spread modeling and resulted in being related to the field-to-spot size ratio. The accuracy of the TPS was proved to be clinically acceptable in all cases but very small and shallow volumes. In this contest, the use of MC to validate TPS results proved to be a reliable procedure for pre-treatment plan verification.

Nanostructured Thermal Protection Systems for Space Exploration Missions

NASA Technical Reports Server (NTRS)

Arnold, J. O.; Chen, Y. K.; Squire, T.; Srivastava, D.; Allen, G., Jr.; Stackpoole, M.; Goldstein, H. E.; Venkatapathy, E.; Loomis, M. P.

2005-01-01

Strong research and development programs in nanotechnology and Thermal Protection Systems (TPS) exist at NASA Ames. Conceptual studies have been undertaken to determine if new, nanostructured materials (composites of existing TPS materials and nanostructured composite fibers) could improve the performance of TPS. To this end, we have studied various candidate heatshields, some composed of existing TPS materials (with known material properties), to provide a baseline for comparison with others that are admixtures of such materials and a nanostructured material. In the latter case, some assumptions were made about the thermal conductivity and strength of the admixture, relative to the baseline TPS material. For the purposes of this study, we have made the conservative assumption that only a small fraction of the remarkable properties of carbon nanotubes (for example) will be realized in the material properties of the admixtures employing them. The heatshields studied included those for Sharp leading edges (appropriate to out-of-orbit entry and aero-maneuvering), probes, an out-of-orbit Apollo Command Module (as a surrogate for NASA's new Crew Exploration Vehicle [CEV]), a Mars Sample Return Vehicle and a large heat shield for Mars aerocapture missions. We report on these conceptual studies, which show that in some cases (not all), significant improvements in the TPS can be achieved through the use of nanostructured materials.

Experimental Design for the Evaluation of Detection Techniques of Hidden Corrosion Beneath the Thermal Protective System of the Space Shuttle Orbiter

NASA Technical Reports Server (NTRS)

Kemmerer, Catherine C.; Jacoby, Joseph A.; Lomness, Janice K.; Hintze, Paul E.; Russell, Richard W.

2007-01-01

The detection of corrosion beneath Space Shuttle Orbiter thermal protective system is traditionally accomplished by removing the Reusable Surface Insulation tiles and performing a visual inspection of the aluminum substrate and corrosion protection system. This process is time consuming and has the potential to damage high cost tiles. To evaluate non-intrusive NDE methods, a Proof of Concept (PoC) experiment was designed and test panels were manufactured. The objective of the test plan was three-fold: establish the ability to detect corrosion hidden from view by tiles; determine the key factor affecting detectability; roughly quantify the detection threshold. The plan consisted of artificially inducing dimensionally controlled corrosion spots in two panels and rebonding tile over the spots to model the thermal protective system of the orbiter. The corrosion spot diameter ranged from 0.100" to 0.600" inches and the depth ranged from 0.003" to 0.020". One panel consisted of a complete factorial array of corrosion spots with and without tile coverage. The second panel consisted of randomized factorial points replicated and hidden by tile. Conventional methods such as ultrasonics, infrared, eddy current and microwave methods have shortcomings. Ultrasonics and IR cannot sufficiently penetrate the tiles, while eddy current and microwaves have inadequate resolution. As such, the panels were interrogated using Backscatter Radiography and Terahertz Imaging. The terahertz system successfully detected artificially induced corrosion spots under orbiter tile and functional testing is in-work in preparation for implementation.

Study of heat sink thermal protection systems for hypersonic research aircraft

NASA Technical Reports Server (NTRS)

Vahl, W. A.; Edwards, C. L. W.

1978-01-01

The feasibility of using a single metallic heat sink thermal protection system (TPS) over a projected flight test program for a hypersonic research vehicle was studied using transient thermal analyses and mission performance calculations. Four materials, aluminum, titanium, Lockalloy, and beryllium, as well as several combinations, were evaluated. Influence of trajectory parameters were considered on TPS and mission performance for both the clean vehicle configuration as well as with an experimental scramjet mounted. From this study it was concluded that a metallic heat sink TPS can be effectively employed for a hypersonic research airplane flight envelope which includes dash missions in excess of Mach 8 and 60 seconds of cruise at Mach numbers greater than 6. For best heat sink TPS match over the flight envelope, Lockalloy and titanium appear to be the most promising candidates

Surface dose measurement with Gafchromic EBT3 film for intensity modulated radiotherapy technique

NASA Astrophysics Data System (ADS)

Akbas, Ugur; Kesen, Nazmiye Donmez; Koksal, Canan; Okutan, Murat; Demir, Bayram; Becerir, Hatice Bilge

2017-09-01

Accurate dose measurement in the buildup region is extremely difficult. Studies have reported that treatment planning systems (TPS) cannot calculate surface dose accurately. The aim of the study was to compare the film measurements and TPS calculations for surface dose in head and neck cancer treatment using intensity modulated radiation therapy (IMRT). IMRT plans were generated for 5 head and neck cancer patients by using Varian Eclipse TPS. Quality assurance (QA) plans of these IMRT plans were created on rando phantoms for surface dose measurements. EBT3 films were cut in size of 2.5 x 2.5 cm2 and placed on the left side, right side and the center of larynx and then the films were irradiated with 6 MV photon beams. The measured doses were compared with TPS. The results of TPS calculations were found to be lower compared to the EBT3 film measurements at all selected points. The lack of surface dose calculation in TPS should be considered while evaluating the radiotherapy plans.

Regeneration of tert-butylhydroquinone by tea polyphenols.

PubMed

Guo, Yafang; Guo, Yahui; Xie, Yunfei; Cheng, Yuliang; Qian, He; Yao, Weirong

2017-05-01

To study the antioxidant capacity (AC) regeneration of tert-butylhydroquinone (TBHQ) by tea polyphenols (TPs), a separable system has been designed for its evaluation. The AC values of three natural food matrices (liquorice, oat, and ginger) and TBHQ regenerated by TPs were all higher than their controls, and similar to the initial values (p<0.05). The average regeneration efficiency (RE) value was 1.49 for these three natural food matrices, and 0.82 for TBHQ. Electron paramagnetic resonance spectroscopy analysis has revealed the synergistic effect of TBHQ and TPs, which arose from the regeneration of TBHQ by TPs. The RE value of TBHQ regeneration by TPs embedded in a gelatine membrane was 0.51. The results demonstrated that TPs showed a capacity for regenerating TBHQ, indicating a potential application in regenerative packaging, whereby one antioxidant would be added to the food matrix, with another one as the regenerator incorporated into the packaging material. Copyright © 2017 Elsevier Ltd. All rights reserved.

Wavelet-domain de-noising technique for THz pulsed spectroscopy

NASA Astrophysics Data System (ADS)

Chernomyrdin, Nikita V.; Zaytsev, Kirill I.; Gavdush, Arsenii A.; Fokina, Irina N.; Karasik, Valeriy E.; Reshetov, Igor V.; Kudrin, Konstantin G.; Nosov, Pavel A.; Yurchenko, Stanislav O.

2014-09-01

De-noising of terahertz (THz) pulsed spectroscopy (TPS) data is an essential problem, since a noise in the TPS system data prevents correct reconstruction of the sample spectral dielectric properties and to perform the sample internal structure studying. There are certain regions in TPS signal Fourier spectrum, where Fourier-domain signal-to-noise ratio is relatively small. Effective de-noising might potentially expand the range of spectrometer spectral sensitivity and reduce the time of waveform registration, which is an essential problem for biomedical applications of TPS. In this work, it is shown how the recent progress in signal processing in wavelet-domain could be used for TPS waveforms de-noising. It demonstrates the ability to perform effective de-noising of TPS data using the algorithm of the Fast Wavelet Transform (FWT). The results of the optimal wavelet basis selection and wavelet-domain thresholding technique selection are reported. Developed technique is implemented for reconstruction of in vivo healthy and deseased skin samplesspectral characteristics at THz frequency range.

Measuring Thermal Conductivity and Moisture Absorption of Cryo-Insulation Materials

NASA Technical Reports Server (NTRS)

Lambert, Michael A.

1998-01-01

NASA is seeking to develop thermal insulation material systems suitable for withstanding both extremely high temperatures encountered during atmospheric re-entry heating and aero- braking maneuvers, as well as extremely low temperatures existing in liquid fuel storage tanks. Currently, materials used for the high temperature insulation or Thermal Protection System (TPS) are different from the low temperature, or cryogenic insulation. Dual purpose materials are necessary to the development of reusable launch vehicles (RLV). The present Space Shuttle (or Space Transportation System, STS) employs TPS materials on the orbiter and cryo-insulation materials on the large fuel tank slung under the orbiter. The expensive fuel tank is jettisoned just before orbit is achieved and it burns up while re-entering over the Indian Ocean. A truly completely reusable launch vehicle must store aR cryogenic fuel internally. The fuel tanks will be located close to the outer surface. In fact the outer skin of the craft will probably also serve as the fuel tank enclosure, as in jet airliners. During a normal launch the combined TPS/cryo-insulation system will serve only as a low temperature insulator, since aerodynamic heating is relatively minimal during ascent to orbit. During re-entry, the combined TPS/cryo-insulation system will serve only as a high temperature insulator, since all the cryogenic fuel will have been expended in orbit. However, in the event of an.aborted launch or a forced/emergency early re-entry, the tanks will still contain fuel, and the TPS/cryo-insulation will have to serve as both low and high temperature insulation. Also, on long duration missions, such as to Mars, very effective cryo-insulation materials are needed to reduce bod off of liquid propellants, thereby reducing necessary tankage volume, weight, and cost. The conventional approach to obtaining both low and high temperature insulation, such as is employed for the X-33 and X-34 spacecraft, is to use separate TPS and cryo-insulation materials, which are connected by means of adhesives or stand-offs (spacers). Three concepts are being considered: (1) the TPS is bonded directly to the cryo-insulation which, in turn, is bonded to the exterior of the tank, (2) stand-offs are used to make a gap between the TPS and the cryo-insulation, which is bonded externally to the tank, (3) TPS is applied directly or with stand-offs to the exterior so the tank, and cryo-insulation is applied directly to the interior of the tank. Many potential problems are inherent in these approaches. For example, mismatch between coefficients of thermal expansion of the TPS and cryo-insulation, as well as aerodynamic loads, could lead to failure of the bond. Internal cryo-insulation must be prevent from entering the sump of the fuel turbo-pump. The mechanical integrity of the stand-off structure (if used) must withstand multiple missions. During ground hold (i.e., prior to launch) moisture condensation must be minimized in the gap between the cryo-insulation and the TPS. The longer term solution requires the development of a single material to act as cryo- insulation during ground hold and as TPS during re-entry. Such a material minimizes complexity and weight while improving reliability and reducing cost.

An Analysis of the Selected Materials Used in Step Measurements During Pre-Fits of Thermal Protection System Tiles and the Accuracy of Measurements Made Using These Selected Materials

NASA Technical Reports Server (NTRS)

Kranz, David William

2010-01-01

The goal of this research project was be to compare and contrast the selected materials used in step measurements during pre-fits of thermal protection system tiles and to compare and contrast the accuracy of measurements made using these selected materials. The reasoning for conducting this test was to obtain a clearer understanding to which of these materials may yield the highest accuracy rate of exacting measurements in comparison to the completed tile bond. These results in turn will be presented to United Space Alliance and Boeing North America for their own analysis and determination. Aerospace structures operate under extreme thermal environments. Hot external aerothermal environments in high Mach number flights lead to high structural temperatures. The differences between tile heights from one to another are very critical during these high Mach reentries. The Space Shuttle Thermal Protection System is a very delicate and highly calculated system. The thermal tiles on the ship are measured to within an accuracy of .001 of an inch. The accuracy of these tile measurements is critical to a successful reentry of an orbiter. This is why it is necessary to find the most accurate method for measuring the height of each tile in comparison to each of the other tiles. The test results indicated that there were indeed differences in the selected materials used in step measurements during prefits of Thermal Protection System Tiles and that Bees' Wax yielded a higher rate of accuracy when compared to the baseline test. In addition, testing for experience level in accuracy yielded no evidence of difference to be found. Lastly the use of the Trammel tool over the Shim Pack yielded variable difference for those tests.

Forward-facing cavity and opposing jet combined thermal protection system

NASA Astrophysics Data System (ADS)

Lu, H. B.; Liu, W. Q.

2012-12-01

This paper focuses on the design of a forward-facing cavity and opposing jet combined configuration for thermal protection system (TPS) of hypersonic vehicles. The cooling efficiency of the combined TPS was investigated numerically, and the numerical method was validated by the related experiment in the open literature. The flow field parameters, aerodynamic force, and surface heat flux distribution were obtained. The detailed numerical results show that this kind of combined TPS has an excellent impact on cooling the nose-tip, and it is suitable for the thermal protection of hypersonic vehicles which require long-range and time to cruise.

Thermal Protection Materials and Systems: Where Have We Been, Where are We Going?

NASA Technical Reports Server (NTRS)

Johnson, Sylvia M.

2016-01-01

Thermal protection materials and systems (TPS) have been critical to fulfilling humankind's desire to explore space. Composite and ceramic materials have enable the early missions to orbit, the moon, the space station, Mars with robots, and sample return. Crewed missions to Mars are being considered, and this places even more demands on TPS materials. This talk will give some history on the materials used for earth and planetary entry and the demands placed upon such materials. TPs needs for future missions, especially to Mars, will be identified and potential solutions discussed.

Coated columbium thermal protection systems: An assessment of technological readiness

NASA Technical Reports Server (NTRS)

Levine, S. R.; Grisaffe, S. J.

1973-01-01

Evaluation and development to date show that of the coated columbium alloys FS-85 coated with R512E shows significant promise for a reusable thermal protection system (TPS) as judged by environmental resistance and the retention of mechanical properties and structural integrity of panels upon repeated reentry simulation. Production of the alloy, the coating, and full-sized TPS panels is well within current manufacturing technology. Small defects which arise from impact damage or from local coating breakdown do not appear to have serious immediate consequences in the use environment anticipated for the space shuttle orbiter TPS.

Geometrical Tile Design for Complex Neighborhoods

PubMed Central

Czeizler, Eugen; Kari, Lila

2009-01-01

Recent research has showed that tile systems are one of the most suitable theoretical frameworks for the spatial study and modeling of self-assembly processes, such as the formation of DNA and protein oligomeric structures. A Wang tile is a unit square, with glues on its edges, attaching to other tiles and forming larger and larger structures. Although quite intuitive, the idea of glues placed on the edges of a tile is not always natural for simulating the interactions occurring in some real systems. For example, when considering protein self-assembly, the shape of a protein is the main determinant of its functions and its interactions with other proteins. Our goal is to use geometric tiles, i.e., square tiles with geometrical protrusions on their edges, for simulating tiled paths (zippers) with complex neighborhoods, by ribbons of geometric tiles with simple, local neighborhoods. This paper is a step toward solving the general case of an arbitrary neighborhood, by proposing geometric tile designs that solve the case of a “tall” von Neumann neighborhood, the case of the f-shaped neighborhood, and the case of a 3 × 5 “filled” rectangular neighborhood. The techniques can be combined and generalized to solve the problem in the case of any neighborhood, centered at the tile of reference, and included in a 3 × (2k + 1) rectangle. PMID:19956398

Protein secretion through autotransporter and two-partner pathways.

PubMed

Jacob-Dubuisson, Françoise; Fernandez, Rachel; Coutte, Loic

2004-11-11

Two distinct protein secretion pathways, the autotransporter (AT) and the two-partner secretion (TPS) pathways are characterized by their apparent simplicity. Both are devoted to the translocation across the outer membrane of mostly large proteins or protein domains. As implied by their name, AT proteins contain their own transporter domain, covalently attached to the C-terminal extremity of the secreted passenger domain, while TPS systems are composed of two separate proteins, with TpsA being the secreted protein and TpsB its specific transporter. In both pathways, the secreted proteins are exported in a Sec-dependent manner across the inner membrane, after which they cross the outer membrane with the help of their cognate transporters. The AT translocator domains and the TpsB proteins constitute distinct families of protein-translocating, outer membrane porins of Gram-negative bacteria. Both types of transporters insert into the outer membrane as beta-barrel proteins possibly forming oligomeric pores in the case of AT and serve as conduits for their cognate secreted proteins or domains across the outer membrane. Translocation appears to be folding-sensitive in both pathways, indicating that AT passenger domains and TpsA proteins cross the periplasm and the outer membrane in non-native conformations and fold progressively at the cell surface. A major difference between AT and TPS pathways arises from the manner by which specificity is established between the secreted protein and its transporter. In AT, the covalent link between the passenger and the translocator domains ensures the translocation of the former without the need for a specific molecular recognition between the two modules. In contrast, the TPS pathway has solved the question of specific recognition between the TpsA proteins and their transporters by the addition to the TpsA proteins of an N-proximal module, the conserved TPS domain, which represents a hallmark of the TPS pathway.

KSC-06pd0022

NASA Image and Video Library

2006-01-11

KENNEDY SPACE CENTER, FLA. - In the Thermal Protection System Facility, Tim Wright, engineering manager with United Space Alliance, tests a new tile, called "Boeing replacement insulation" or "BRI-18." The new tiles will gradually replace older tiles around main landing gear doors, external tank doors and nose landing gear doors. Currently, 10 tiles have been processed inside the facility. Discovery will receive the first BRI-18 tiles. Technicians inside the Orbiter Processing Facility are performing fit checks and will begin bonding the tiles to the vehicle this month. The raw material is manufactured by The Boeing Company in Huntington Beach, Calif. Replacing older tile with the BRI-18 tile in strategic areas is one of the Columbia Accident Investigation Board's recommendations to strengthen the orbiters. The tiles are more impact resistant than previous designs, enhancing the crew’s safety.

KSC-06pd0021

NASA Image and Video Library

2006-01-11

KENNEDY SPACE CENTER, FLA. - In the Thermal Protection System Facility, Tim Wright, engineering manager with United Space Alliance, tests a new tile, called "Boeing replacement insulation" or "BRI-18." The new tiles will gradually replace older tiles around main landing gear doors, external tank doors and nose landing gear doors. Currently, 10 tiles have been processed inside the facility. Discovery will receive the first BRI-18 tiles. Technicians inside the Orbiter Processing Facility are performing fit checks and will begin bonding the tiles to the vehicle this month. The raw material is manufactured by The Boeing Company in Huntington Beach, Calif. Replacing older tile with the BRI-18 tile in strategic areas is one of the Columbia Accident Investigation Board's recommendations to strengthen the orbiters. The tiles are more impact resistant than previous designs, enhancing the crew’s safety.

Shell tile thermal protection system

NASA Technical Reports Server (NTRS)

Macconochie, I. O.; Lawson, A. G.; Kelly, H. N. (Inventor)

1984-01-01

A reusable, externally applied thermal protection system for use on aerospace vehicles subject to high thermal and mechanical stresses utilizes a shell tile structure which effectively separates its primary functions as an insulator and load absorber. The tile consists of structurally strong upper and lower metallic shells manufactured from materials meeting the thermal and structural requirements incident to tile placement on the spacecraft. A lightweight, high temperature package of insulation is utilized in the upper shell while a lightweight, low temperature insulation is utilized in the lower shell. Assembly of the tile which is facilitated by a self-locking mechanism, may occur subsequent to installation of the lower shell on the spacecraft structural skin.

Heath Monitoring of Thermal Protection Systems - Preliminary Measurements and Design Specifications

NASA Technical Reports Server (NTRS)

Scott, D. A.; Price, D. C.

2007-01-01

The work reported here is the first stage of a project that aims to develop a health monitoring system for Thermal Protection Systems (TPS) that enables a vehicle to safely re-enter the Earth's atmosphere. The TPS health monitoring system is to be integrated into an existing acoustic emissions-based Concept Demonstrator, developed by CSIRO, which has been previously demonstrated for evaluating impact damage of aerospace systems.

Evaluation of coated columbium alloy heat shields for space shuttle thermal protection system application. Volume 3, phase 3: Full size TPS evaluation

NASA Technical Reports Server (NTRS)

Baer, J. W.; Black, W. E.

1974-01-01

The thermal protection system (TPS), designed for incorporation with space shuttle orbiter systems, consists of one primary heat shield thermally and structurally isolated from the test fixture by eight peripheral guard panels, all encompassing an area of approximately 12 sq ft. TPS components include tee-stiffened Cb 752/R-512E heat shields, bi-metallic support posts, panel retainers, and high temperature insulation blankets. The vehicle primary structure was simulated by a titanium skin, frames, and stiffeners. Test procedures, manufacturing processes, and methods of analysis are fully documented. For Vol. 1, see N72-30948; for Vol. 2, see N74-15660.

Petroleum Systems and Geologic Assessment of Oil and Gas Resources in the Wind River Basin Province, Wyoming

USGS Publications Warehouse

,

2007-01-01

The purpose of the U.S. Geological Survey's (USGS) National Oil and Gas Assessment is to develop geologically based hypotheses regarding the potential for additions to oil and gas reserves in priority areas of the United States. The U.S. Geological Survey (USGS) recently completed an assessment of the undiscovered oil and gas potential of the Wind River Basin Province which encompasses about 4.7 million acres in central Wyoming. The assessment is based on the geologic elements of each total petroleum system (TPS) defined in the province, including hydrocarbon source rocks (source-rock maturation, hydrocarbon generation, and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and hydrocarbon traps (trap formation and timing). Using this geologic framework, the USGS defined three TPSs: (1) Phosphoria TPS, (2) Cretaceous-Tertiary TPS, and (3) Waltman TPS. Within these systems, 12 Assessment Units (AU) were defined and undiscovered oil and gas resources were quantitatively estimated within 10 of the 12 AUs.

STS-335 crew training, EVA TPS Overview with instructor John Ray

NASA Image and Video Library

2010-11-03

JSC2010-E-183519 (3 Nov. 2010) --- NASA astronauts Doug Hurley, STS-135 pilot; and Sandy Magnus, mission specialist, participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center. STS-135 is planned to be the final mission of the space shuttle program. Photo credit: NASA or National Aeronautics and Space Administration

Tile Drainage Expansion Detection using Satellite Soil Moisture Dynamics

NASA Astrophysics Data System (ADS)

Jacobs, J. M.; Cho, E.; Jia, X.

2017-12-01

In the past two decades, tile drainage installation has accelerated throughout the Red River of the North Basin (RRB) in parts of western Minnesota, eastern North Dakota, and a small area of northeastern South Dakota, because the flat topography and low-permeability soils in this region necessitated the removal of excess water to improve crop production. Interestingly, streamflow in the Red River has markedly increased and six of 13 major floods during the past century have occurred since the late 1990s. It has been suggested that the increase in RRB flooding could be due to change in agricultural practices, including extensive tile drainage installation. Reliable information on existing and future tile drainage installation is greatly needed to capture the rapid extension of tile drainage systems and to locate tile drainage systems in the north central U.S. including the RRB region. However, there are few reliable data of tile drainage installation records, except tile drainage permit records in the Bois de Sioux watershed (a sub-basin in southern part of the RRB where permits are required for tile drainage installation). This study presents a tile drainage expansion detection method based on a physical principle that the soil-drying rate may increase with increasing tile drainage for a given area. In order to capture the rate of change in soil drying rate with time over entire RRB (101,500 km2), two satellite-based microwave soil moisture records from the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) and AMSR2 were used during 2002 to 2016. In this study, a sub-watershed level (HUC10) potential tile drainage growth map was developed and the results show good agreement with tile drainage permit records of six sub-watersheds in the Bois de Sioux watershed. Future analyses will include improvement of the potential tile drainage map through additional information using optical- and thermal-based sensor products and evaluation of its hydrological impacts on intensity, duration, and frequency of extreme streamflow from watershed to basin scale.

Air Augmented Rocket Propulsion Concepts

DTIC Science & Technology

1988-04-01

T’S systems is hybrid lrPS systems which are a combination of external insulation with the two remaining types of TPS systems. The key considerations...atmosphere. HYBRID SYSTEMS are systems which employ high temperature external insulation in the stagnation regior of the vehicle and a metallic system...good possibility of reducing weight by up to 40% in selective high temperature areas by using the SuperA~loy and hybrid SuperAlloy/Titanium multiwall TPS

A Collaborative Analysis Tool for Thermal Protection Systems for Single Stage to Orbit Launch Vehicles

NASA Technical Reports Server (NTRS)

Alexander, Reginald; Stanley, Thomas Troy

2001-01-01

Presented is a design tool and process that connects several disciplines which are needed in the complex and integrated design of high performance reusable single stage to orbit (SSTO) vehicles. Every system is linked to all other systems, as is the case with SSTO vehicles with air breathing propulsion, which is currently being studied by the National Aeronautics and Space Administration (NASA). In particular, the thermal protection system (TPS) is linked directly to almost every major system. The propulsion system pushes the vehicle to velocities on the order of 15 times the speed of sound in the atmosphere before pulling up to go to orbit which results in high temperatures on the external surfaces of the vehicle. Thermal protection systems to maintain the structural integrity of the vehicle must be able to mitigate the heat transfer to the structure and be lightweight. Herein lies the interdependency, in that as the vehicle's speed increases, the TPS requirements are increased. And as TPS masses increase the effect on the propulsion system and all other systems is compounded. To adequately calculate the TPS mass of this type of vehicle several engineering disciplines and analytical tools must be used preferably in an environment that data is easily transferred and multiple iterations are easily facilitated.

X-33 Base Region Thermal Protection System Design Study

NASA Technical Reports Server (NTRS)

Lycans, Randal W.

1998-01-01

The X-33 is an advanced technology demonstrator for validating critical technologies and systems required for an operational Single-Stage-to-Orbit (SSTO) Reusuable Launch Vehicle (RLV). Currently under development by a unique contractor/government team led by Lockheed- Martin Skunk Works (LMSW), and managed by Marshall Space Flight Center (MSFC), the X-33 will be the prototype of the first new launch system developed by the United States since the advent of the space shuttle. This paper documents a design trade study of the X-33 base region thermal protection system (TPS). Two candidate designs were evaluated for thermal performance and weight. The first candidate was a fully reusable metallic TPS using Inconel honeycomb panels insulated with high temperature fibrous insulation, while the second was an ablator/insulator sprayed on the metallic skin of the vehicle. The TPS configurations and insulation thickness requirements were determined for the predicted main engine plume heating environments and base region entry aerothermal environments. In addition to thermal analysis of the design concepts, sensitivity studies were performed to investigate the effect of variations in key parameters of the base TPS analysis.

Decomposability and convex structure of thermal processes

NASA Astrophysics Data System (ADS)

Mazurek, Paweł; Horodecki, Michał

2018-05-01

We present an example of a thermal process (TP) for a system of d energy levels, which cannot be performed without an instant access to the whole energy space. This TP is uniquely connected with a transition between some states of the system, that cannot be performed without access to the whole energy space even when approximate transitions are allowed. Pursuing the question about the decomposability of TPs into convex combinations of compositions of processes acting non-trivially on smaller subspaces, we investigate transitions within the subspace of states diagonal in the energy basis. For three level systems, we determine the set of extremal points of these operations, as well as the minimal set of operations needed to perform an arbitrary TP, and connect the set of TPs with thermomajorization criterion. We show that the structure of the set depends on temperature, which is associated with the fact that TPs cannot increase deterministically extractable work from a state—the conclusion that holds for arbitrary d level system. We also connect the decomposability problem with detailed balance symmetry of an extremal TPs.

Monitoring of Thermal Protection Systems and MMOD using Robust Self-Organizing Optical Fiber Sensing Networks

NASA Technical Reports Server (NTRS)

Richards, Lance

2014-01-01

The general aim of this work is to develop and demonstrate a prototype structural health monitoring system for thermal protection systems that incorporates piezoelectric acoustic emission (AE) sensors to detect the occurrence and location of damaging impacts, such as those from Micrometeoroid Orbital Debris (MMOD). The approach uses an optical fiber Bragg grating (FBG) sensor network to evaluate the effect of detected damage on the thermal conductivity of the TPS material. Following detection of an impact, the TPS would be exposed to a heat source, possibly the sun, and the temperature distribution on the inner surface in the vicinity of the impact measured by the FBG network. A similar procedure could also be carried out as a screening test immediately prior to re-entry. The implications of any detected anomalies in the measured temperature distribution will be evaluated for their significance in relation to the performance of the TPS during reentry. Such a robust TPS health monitoring system would ensure overall crew safety throughout the mission, especially during reentry.

Beautiful Math, Part 5: Colorful Archimedean Tilings from Dynamical Systems.

PubMed

Ouyang, Peichang; Zhao, Weiguo; Huang, Xuan

2015-01-01

The art of tiling originated very early in the history of civilization. Almost every known human society has made use of tilings in some form or another. In particular, tilings using only regular polygons have great visual appeal. Decorated regular tilings with continuous and symmetrical patterns were widely used in decoration field, such as mosaics, pavements, and brick walls. In science, these tilings provide inspiration for synthetic organic chemistry. Building on previous CG&#x0026;A &#x201C;Beautiful Math&#x201D; articles, the authors propose an invariant mapping method to create colorful patterns on Archimedean tilings (1-uniform tilings). The resulting patterns simultaneously have global crystallographic symmetry and local cyclic or dihedral symmetry.

A 20-year and 46,000-specimen journey to Paris reveals the influence of reporting systems and passive peer feedback on pathologist practice patterns.

PubMed

VandenBussche, Christopher J; Allison, Derek B; Gupta, Mohit; Ali, Syed Z; Rosenthal, Dorothy L

2018-05-14

An important goal of The Paris System for Reporting Urinary Cytology (TPS) is to reduce unnecessary atypical diagnoses given to urinary tract cytology (UTC) specimens. Since implementation of TPS at the study institution in 2016, the institutional atypical rate has declined only slightly. The authors speculated that TPS might not have had an immediate impact because several faculty members were involved in TPS committees and because TPS contains elements that already had been integrated into institutional practice. To identify factors contributing to alterations in the institutional atypical rate, the authors examined their practice over the last 22 years. UTC specimens submitted to the study laboratory between August 11, 1995, and August 10, 2017, were identified. Specimens were linked to the responsible pathologist, specimen diagnosis and type, association with high-grade urothelial carcinoma, and relevant cytomorphologic features. An increase in the institutional atypical rate occurred between 2002 and 2005. The atypical rate among individual pathologists also peaked during this same time. The increase coincided with an increase in the use of UTC and the arrival of a pathologist with a higher rate of atypical diagnoses. A substantial decrease in the institutional atypical rate occurred between 2005 and 2010 and coincided with the creation of the Johns Hopkins Hospital Template, the authors' first standardized reporting system for UTC specimens. The use of reporting systems (Johns Hopkins Hospital Template and TPS) has coincided with decreases in the institutional atypical rate at the study institution. An individual pathologist may influence the practice patterns of his or her colleagues, resulting in fluctuations in the institutional rate of atypia over time. Cancer Cytopathol 2018. © 2018 American Cancer Society. © 2018 American Cancer Society.

Trust, but verify - Accuracy of clinical commercial radiation Treatment Planning Systems

NASA Astrophysics Data System (ADS)

Lehmann, J.; Kenny, J.; Lye, J.; Dunn, L.; Williams, I.

2014-03-01

Computer based Treatment Planning Systems (TPS) are used worldwide to design and calculate treatment plans for treating radiation therapy patients. TPS are generally well designed and thoroughly tested by their developers and local physicists prior to clinical use. However, the wide-reaching impact of their accuracy warrants ongoing vigilance. This work reviews the findings of the Australian national audit system and provides recommendations for checks of TPS. The Australian Clinical Dosimetry Service (ACDS) has designed and implemented a national system of audits, currently in a three year test phase. The Level III audits verify the accuracy of a beam model of a facility's TPS through a comparison of measurements with calculation at selected points in an anthropomorphic phantom. The plans are prescribed by the ACDS and all measurement equipment is brought in for independent onsite measurements. In this first version of audits, plans are comparatively simple, involving asymmetric fields, wedges and inhomogeneities. The ACDS has performed 14 Level III audits to-date. Six audits returned at least one measurement at Action Level, indicating that the measured dose differed more than 3.3% (but less than 5%) from the planned dose. Two audits failed (difference >5%). One fail was caused by a data transmission error coupled with quality assurance (QA) not being performed. The second fail was investigated and reduced to Action Level with the onsite audit team finding phantom setup at treatment a contributing factor. The Action Level results are attributed to small dose calculation deviations within the TPS, which are investigated and corrected by the facilities. Small deviations exist in clinical TPS which can add up and can combine with output variations to result in unacceptable variations. Ongoing checks and independent audits are recommended.

KENNEDY SPACE CENTER, FLA. -- United Space Alliance (USA) Manager of the Thermal Protection System (TPS) Facility Martin Wilson (right) briefs NASA Deputy Associate Administrator for Space Station and Shuttle Programs Michael Kostelnik (left) on the properties of a thermal blanket used in the Shuttle's TPS. NASA and USA Space Shuttle program management are participating in a leadership workday. The day is intended to provide management with an in-depth, hands-on look at Shuttle processing activities at KSC.

NASA Image and Video Library

2003-12-19

KENNEDY SPACE CENTER, FLA. -- United Space Alliance (USA) Manager of the Thermal Protection System (TPS) Facility Martin Wilson (right) briefs NASA Deputy Associate Administrator for Space Station and Shuttle Programs Michael Kostelnik (left) on the properties of a thermal blanket used in the Shuttle's TPS. NASA and USA Space Shuttle program management are participating in a leadership workday. The day is intended to provide management with an in-depth, hands-on look at Shuttle processing activities at KSC.

SU-F-T-160: Commissioning of a Single-Room Double-Scattering Proton Therapy System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, H; Ahmad, S; Chen, Y

2016-06-15

Purpose: To report the detailed commissioning experience for a compact double-scattering Mevion S250 proton therapy system at a University Cancer Center site. Methods: The commissioning of the proton therapy system mainly consisted of ensuring integrity of mechanical and imaging system, beam data collection, and commissioning of a treatment planning system (TPS). First, mechanical alignment and imaging were tested including safety, interlocks, positional accuracy of couch and gantry, image quality, mechanical and imaging isocenter and so on. Second, extensive beam data (outputs, PDDs, and profiles) were collected and analyzed through effective sampling of range (R) and modulation width (M) from 24more » beam options. Three different output (cGy/MU) prediction models were also commissioned as primary and secondary MU calculation tool. Third, the Varian Eclipse TPS was commissioned through five sets of data collections (in-water Bragg peak scans, in-air longitudinal fluence scans, in-air lateral profiles, in-air half-beam profiles, and an HU-to-stopping-power conversion curve) and accuracy of TPS calculation was tested using in-water scans and dose measurements with a 2D array detector with block and range compensator. Finally, an anthropomorphic phantom was scanned and heterogeneity effects were tested by inserting radiochromic films in the phantom and PET activation scans for range verification in conjunction with end-to-end test. Results: Beam characteristics agreed well with the vendor specifications; however, minor mismatches in R and M were found in some measurements during the beam data collection. These were reflected into the TPS commissioning such that the TPS could accurately predict the R and M within tolerance levels. The output models had a good agreement with measured outputs (<3% error). The end-to-end test using the film and PET showed reasonably the TPS predicted dose, R and M in heterogeneous medium. Conclusion: The proton therapy system was successfully commissioned and was released for clinical use.« less

Evaluation of the hooghoudt and kirkham tile drain equations in the soil and water assessment tool to simulate tile flow and nitrate-nitrogen.

PubMed

Moriasi, Daniel N; Gowda, Prasanna H; Arnold, Jeffrey G; Mulla, David J; Ale, Srinivasulu; Steiner, Jean L; Tomer, Mark D

2013-11-01

Subsurface tile drains in agricultural systems of the midwestern United States are a major contributor of nitrate-N (NO-N) loadings to hypoxic conditions in the Gulf of Mexico. Hydrologic and water quality models, such as the Soil and Water Assessment Tool, are widely used to simulate tile drainage systems. The Hooghoudt and Kirkham tile drain equations in the Soil and Water Assessment Tool have not been rigorously tested for predicting tile flow and the corresponding NO-N losses. In this study, long-term (1983-1996) monitoring plot data from southern Minnesota were used to evaluate the SWAT version 2009 revision 531 (hereafter referred to as SWAT) model for accurately estimating subsurface tile drain flows and associated NO-N losses. A retention parameter adjustment factor was incorporated to account for the effects of tile drainage and slope changes on the computation of surface runoff using the curve number method (hereafter referred to as Revised SWAT). The SWAT and Revised SWAT models were calibrated and validated for tile flow and associated NO-N losses. Results indicated that, on average, Revised SWAT predicted monthly tile flow and associated NO-N losses better than SWAT by 48 and 28%, respectively. For the calibration period, the Revised SWAT model simulated tile flow and NO-N losses within 4 and 1% of the observed data, respectively. For the validation period, it simulated tile flow and NO-N losses within 8 and 2%, respectively, of the observed values. Therefore, the Revised SWAT model is expected to provide more accurate simulation of the effectiveness of tile drainage and NO-N management practices. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Thermal Protection and Control

NASA Technical Reports Server (NTRS)

Greene, Effie E.

2013-01-01

During all phases of a spacecraft's mission, a Thermal Protection System (TPS) is needed to protect the vehicle and structure from extreme temperatures and heating. When designing TPS, low weight and cost while ensuring the protection of the vehicle is highly desired. There are two main types of TPS, ablative and reusable. The Apollo missions needed ablators due to the high heat loads from lunar reentry. However, when the desire for a reusable space vehicle emerged, the resultant_ Space Shuttle program propelled a push for the development of reusable TPS. With the growth of reqsable TPS, the need for ablators declined, triggering a drop off of the ablator industry. As a result, the expertise was not heavily maintained within NASA or the industry. When the Orion Program initiated a few years back, a need. for an ablator reemerged. Yet, due to of the lack of industry capability, redeveloping the ablator material took several years and came at a high cost. As NASA looks towards the future with both the Orion and Commercial Crew Programs, a need to preserve reusable, ablative, and other TPS technologies is essential. Research of the different TPS materials alongside their properties, capabilities, and manufacturing process was performed, and the benefits of the materials were analyzed alongside the future of TPS. Knowledge of the different technologies has the ability to help us know what expertise to maintain and ensure a lack in the industry does not occur again.

Elevated waterproof access floor system and method of making the same

NASA Technical Reports Server (NTRS)

Cohen, Marc M. (Inventor)

1987-01-01

An elevated waterproof access floor system having subfloor channels or compartments for power lines, gas lines or the like is adapted such that it can be opened and subsequently resealed without destroying the waterproofing and without destroying its aesthetic appearance. A multiplicity of tiles are supported on a support grid, and a flooring sheet is supported on the tiles. Attachment means are provided to prevent lateral but not vertical movement of the flooring sheet with respect to the tiles so that the flooring sheet can be lifted off the tiles, but when the flooring sheet is supported on the tiles, no lateral slipping will occur. The flooring sheet is made of a heat resealable material, so that it can be cut away in sections, and the tiles therebelow lifted off, to provide access to subfloor compartments.

Commissioning results of an automated treatment planning verification system

PubMed Central

Mason, Bryan E.; Robinson, Ronald C.; Kisling, Kelly D.; Kirsner, Steven M.

2014-01-01

A dose calculation verification system (VS) was acquired and commissioned as a second check on the treatment planning system (TPS). This system reads DICOM CT datasets, RT plans, RT structures, and RT dose from the TPS and automatically, using its own collapsed cone superposition/convolution algorithm, computes dose on the same CT dataset. The system was commissioned by extracting basic beam parameters for simple field geometries and dose verification for complex treatments. Percent depth doses (PDD) and profiles were extracted for field sizes using jaw settings 3 × 3 cm2 ‐ 40 × 40 cm2 and compared to measured data, as well as our TPS model. Smaller fields of 1 × 1 cm2 and 2 × 2 cm2 generated using the multileaf collimator (MLC) were analyzed in the same fashion as the open fields. In addition, 40 patient plans consisting of both IMRT and VMAT were computed and the following comparisons were made: 1) TPS to the VS, 2) VS to measured data, and 3) TPS to measured data where measured data is both ion chamber (IC) and film measurements. Our results indicated for all field sizes using jaw settings PDD errors for the VS on average were less than 0.87%, 1.38%, and 1.07% for 6x, 15x, and 18x, respectively, relative to measured data. PDD errors for MLC field sizes were less than 2.28%, 1.02%, and 2.23% for 6x, 15x, and 18x, respectively. The infield profile analysis yielded results less than 0.58% for 6x, 0.61% for 15x, and 0.77% for 18x for the VS relative to measured data. Analysis of the penumbra region yields results ranging from 66.5% points, meeting the DTA criteria to 100% of the points for smaller field sizes for all energies. Analysis of profile data for field sizes generated using the MLC saw agreement with infield DTA analysis ranging from 68.8%–100% points passing the 1.5%/1.5 mm criteria. Results from the dose verification for IMRT and VMAT beams indicated that, on average, the ratio of TPS to IC and VS to IC measurements was 100.5 ± 1.9% and 100.4 ± 1.3%, respectively, while our TPS to VS was 100.1 ± 1.0%. When comparing the TPS and VS to film measurements, the average percentage pixels passing a 3%/3 mm criteria based gamma analysis were 96.6 ± 4.2% and 97 ± 5.6%, respectively. When the VS was compared to the TPS, on average 98.1 ± 5.3% of pixels passed the gamma analysis. Based upon these preliminary results, the VS system should be able to calculate dose adequately as a verification tool of our TPS. PACS number: 87.55.km PMID:25207567

STS-335 crew training, EVA TPS Overview with instructor John Ray

NASA Image and Video Library

2010-11-03

JSC2010-E-183523 (3 Nov. 2010) --- NASA astronauts Rex Walheim (left), STS-135 mission specialist; and Doug Hurley, pilot, participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center. STS-135 is planned to be the final mission of the space shuttle program. Photo credit: NASA or National Aeronautics and Space Administration

STS-335 crew training, EVA TPS Overview with instructor John Ray

NASA Image and Video Library

2010-11-03

JSC2010-E-183524 (3 Nov. 2010) --- NASA astronauts Rex Walheim (left), STS-135 mission specialist; and Doug Hurley, pilot, participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center. STS-135 is planned to be the final mission of the space shuttle program. Photo credit: NASA or National Aeronautics and Space Administration

The total position-spread tensor: Spin partition

DOE Office of Scientific and Technical Information (OSTI.GOV)

El Khatib, Muammar, E-mail: elkhatib@irsamc.ups-tlse.fr; Evangelisti, Stefano, E-mail: stefano@irsamc.ups-tlse.fr; Leininger, Thierry, E-mail: Thierry.Leininger@irsamc.ups-tlse.fr

2015-03-07

The Total Position Spread (TPS) tensor, defined as the second moment cumulant of the position operator, is a key quantity to describe the mobility of electrons in a molecule or an extended system. In the present investigation, the partition of the TPS tensor according to spin variables is derived and discussed. It is shown that, while the spin-summed TPS gives information on charge mobility, the spin-partitioned TPS tensor becomes a powerful tool that provides information about spin fluctuations. The case of the hydrogen molecule is treated, both analytically, by using a 1s Slater-type orbital, and numerically, at Full Configuration Interactionmore » (FCI) level with a V6Z basis set. It is found that, for very large inter-nuclear distances, the partitioned tensor growths quadratically with the distance in some of the low-lying electronic states. This fact is related to the presence of entanglement in the wave function. Non-dimerized open chains described by a model Hubbard Hamiltonian and linear hydrogen chains H{sub n} (n ≥ 2), composed of equally spaced atoms, are also studied at FCI level. The hydrogen systems show the presence of marked maxima for the spin-summed TPS (corresponding to a high charge mobility) when the inter-nuclear distance is about 2 bohrs. This fact can be associated to the presence of a Mott transition occurring in this region. The spin-partitioned TPS tensor, on the other hand, has a quadratical growth at long distances, a fact that corresponds to the high spin mobility in a magnetic system.« less

Leadless Cardiac Pacemaker Implantation After Lead Extraction in Patients With Severe Device Infection.

PubMed

Kypta, Alexander; Blessberger, Hermann; Kammler, Juergen; Lambert, Thomas; Lichtenauer, Michael; Brandstaetter, Walter; Gabriel, Michael; Steinwender, Clemens

2016-09-01

Conventional pacemaker therapy is limited by short- and long-term complications, most notably device infection. Transcatheter pacing systems (TPS) may be beneficial in this kind of patients as they eliminate the need for a device pocket and leads and thus may reduce the risk of re-infection. We assessed a novel procedure in 6 patients with severe device infection who were pacemaker dependent. After lead extraction a single chamber TPS was implanted into the right ventricle. Of the 6 patients who underwent lead extraction due to severe device infection at our institution, 3 were diagnosed with a pocket infection only, whereas the other 3 showed symptoms of both pocket and lead infection. Successful lead extraction and TPS implantation was accomplished in all patients. Four patients were bridged with a temporary pacemaker between 2 hours and 2 days after lead extraction, whereas 2 patients had the TPS implanted during the same procedure just before traditional pacemaker system removal. All patients stayed free of infection during the follow-up period of 12 weeks. An additional positron emission tomography scan was performed in each patient and indicated no signs of an infection around the TPS. Transcather pacemaker implantation was safe and feasible in 6 patients and did not result in re-infection even if implanted before removal of the infected pacemaker system within the same procedure. Therefore, implantation of a TPS may be an option for patients with severe device infection, especially in those with blocked venous access or who are pacemaker dependent. © 2016 Wiley Periodicals, Inc.

From Tomography to Material Properties of Thermal Protection Systems

NASA Technical Reports Server (NTRS)

Mansour, Nagi N.; Panerai, Francesco; Ferguson, Joseph C.; Borner, Arnaud; Barnhardt, Michael; Wright, Michael

2017-01-01

A NASA Ames Research Center (ARC) effort, under the Entry Systems Modeling (ESM) project, aims at developing micro-tomography (micro-CT) experiments and simulations for studying materials used in hypersonic entry systems. X-ray micro-tomography allows for non-destructive 3D imaging of a materials micro-structure at the sub-micron scale, providing fiber-scale representations of porous thermal protection systems (TPS) materials. The technique has also allowed for In-situ experiments that can resolve response phenomena under realistic environmental conditions such as high temperature, mechanical loads, and oxidizing atmospheres. Simulation tools have been developed at the NASA Ames Research Center to determine material properties and material response from the high-fidelity tomographic representations of the porous materials with the goal of informing macroscopic TPS response models and guiding future TPS design.

Shuttle Damage/Repair from the Perspective of Hypersonic Boundary Layer Transition - Experimental Results

NASA Technical Reports Server (NTRS)

Horvath, Thomas J.; Berry, Scott A.; Merski, N. Ronald; Berger, Karen T.; Buck, Gregory M.; Liechty, Derek S.; Schneider, Steven P.

2006-01-01

An overview is provided of the experimental wind tunnel program conducted at the NASA Langley Research Center Aerothermodynamics Laboratory in support of an agency-wide effort to prepare the Shuttle Orbiter for Return-to-Flight. The effect of an isolated protuberance and an isolated rectangular cavity on hypersonic boundary layer transition onset on the windward surface of the Shuttle Orbiter has been experimentally characterized. These experimental studies were initiated to provide a protuberance and cavity effects database for developing hypersonic transition criteria to support on-orbit disposition of thermal protection system damage or repair. In addition, a synergistic experimental investigation was undertaken to assess the impact of an isolated mass-flow entrainment source (simulating pyrolysis/outgassing from a proposed tile repair material) on boundary layer transition. A brief review of the relevant literature regarding hypersonic boundary layer transition induced from cavities and localized mass addition from ablation is presented. Boundary layer transition results were obtained using 0.0075-scale Orbiter models with simulated tile damage (rectangular cavities) of varying length, width, and depth and simulated tile damage or repair (protuberances) of varying height. Cavity and mass addition effects were assessed at a fixed location (x/L = 0.3) along the model centerline in a region of near zero pressure gradient. Cavity length-to-depth ratio was systematically varied from 2.5 to 17.7 and length-to-width ratio of 1 to 8.5. Cavity depth-to-local boundary layer thickness ranged from 0.5 to 4.8. Protuberances were located at several sites along the centerline and port/starboard attachment lines along the chine and wing leading edge. Protuberance height-to-boundary layer thickness was varied from approximately 0.2 to 1.1. Global heat transfer images and heating distributions of the Orbiter windward surface using phosphor thermography were used to infer the state of the boundary layer (laminar, transitional, or turbulent). Test parametrics include angles-of-attack of 30 deg and 40 deg, sideslip angle of 0 deg, freestream Reynolds numbers from 0.02x106 to 7.3x106 per foot, edge-to-wall temperature ratio from 0.4 to 0.8, and normal shock density ratios of approximately 5.3, 6.0, and 12 in Mach 6 air, Mach 10 air, and Mach 6 CF4, respectively. Testing to simulate the effects of ablation from a proposed tile repair concept indicated that transition was not a concern. The experimental protuberance and cavity databases highlighted in this report were used to formulate boundary layer transition correlations that were an integral part of an analytical process to disposition observed Orbiter TPS damage during STS- 114.

Learning from business: incorporating the Toyota Production System into nursing curricula.

PubMed

Serembus, Joanne Farley; Meloy, Faye; Posmontier, Bobbie

2012-12-01

The faculty at Drexel University decided to investigate a new model to transform nursing education, aiming to produce a new skill set that would serve to improve the transition of nursing graduates from academic settings to practice, to better serve the needs of patients and reduce medical error. Faculty looked to the Toyota Production System (TPS), which has established credibility in industry and health care settings. TPS has demonstrated increased efficiency and effectiveness, reduced cost, and enhanced achievement of stated goals. Drexel University is the first academic institution to incorporate the principles of the TPS into nursing education. Copyright © 2012 Elsevier Inc. All rights reserved.

Coatings and Surface Treatments for Reusable Entry Systems

NASA Technical Reports Server (NTRS)

Johnson, Sylvia M.

2016-01-01

This talk outlines work in coatings for TPS done at NASA Ames. coatings and surface treatments on reusable TPS are critical for controlling the behavior of the materials. coatings discussed include RCG, TUFI and HETC. TUFROc is also discussed.

Lunar Return Reentry Thermal Analysis of a Generic Crew Exploration Vehicle Wall Structures

NASA Technical Reports Server (NTRS)

Ko, William L.; Tran, Van T.; Bowles, Jeff

2007-01-01

Thermostructural analysis was performed on generic crew exploration vehicle (GCEV) heat shielded wall structures subjected to reentry heating rates based on five potential lunar return reentry trajectories. The GCEV windward outer wall is fabricated with a graphite/epoxy composite honeycomb sandwich panel and the inner wall with an aluminum honeycomb sandwich panel. The outer wall is protected with an ablative Avcoat-5026-39H/CG thermal protection system (TPS). A virtual ablation method (a graphical approximation) developed earlier was further extended, and was used to estimate the ablation periods, ablation heat loads, and the TPS recession layer depths. It was found that up to 83 95 percent of the total reentry heat load was dissipated in the TPS ablation process, leaving a small amount (3-15 percent) of the remaining total reentry heat load to heat the virgin TPS and maintain the TPS surface at the ablation temperature, 1,200 F. The GCEV stagnation point TPS recession layer depths were estimated to be in the range of 0.280-0.910 in, and the allowable minimum stagnation point TPS thicknesses that could maintain the substructural composite sandwich wall at the limit temperature of 300 F were found to be in the range of 0.767-1.538 in. Based on results from the present analyses, the lunar return abort ballistic reentry was found to be quite attractive because it required less TPS weight than the lunar return direct, the lunar return skipping, or the low Earth orbit guided reentry, and only 11.6 percent more TPS weight than the low Earth orbit ballistic reentry that will encounter a considerable weight penalty to obtain the Earth orbit. The analysis also showed that the TPS weight required for the lunar return skipping reentry was much more than the TPS weight necessary for any of the other reentry trajectories considered.

Tile-based Level of Detail for the Parallel Age

DOE Office of Scientific and Technical Information (OSTI.GOV)

Niski, K; Cohen, J D

Today's PCs incorporate multiple CPUs and GPUs and are easily arranged in clusters for high-performance, interactive graphics. We present an approach based on hierarchical, screen-space tiles to parallelizing rendering with level of detail. Adapt tiles, render tiles, and machine tiles are associated with CPUs, GPUs, and PCs, respectively, to efficiently parallelize the workload with good resource utilization. Adaptive tile sizes provide load balancing while our level of detail system allows total and independent management of the load on CPUs and GPUs. We demonstrate our approach on parallel configurations consisting of both single PCs and a cluster of PCs.

Development Of Metallic Thermal Protection System For The Expert Re-Entry Vehicle: Design Verification

NASA Astrophysics Data System (ADS)

Fatemi, Javad

2011-05-01

The thermal protection system of the EXPERT re-entry vehicle is subjected to accelerations, vibrations, acoustic and shock loads during launch and aero-heating loads and aerodynamic forces during re-entry. To fully understand the structural and thermomechanical performances of the TPS, heat transfer analysis, thermal stress analysis, and thermal buckling analysis must be performed. This requires complex three-dimensional thermal and structural models of the entire TPS including the insulation and sensors. Finite element (FE) methods are employed to assess the thermal and structural response of the TPS to the mechanical and aerothermal loads. The FE analyses results are used for the design verification and design improvement of the EXPERT thermal protection system.

Selecting the most appropriate time points to profile in high-throughput studies

PubMed Central

Kleyman, Michael; Sefer, Emre; Nicola, Teodora; Espinoza, Celia; Chhabra, Divya; Hagood, James S; Kaminski, Naftali; Ambalavanan, Namasivayam; Bar-Joseph, Ziv

2017-01-01

Biological systems are increasingly being studied by high throughput profiling of molecular data over time. Determining the set of time points to sample in studies that profile several different types of molecular data is still challenging. Here we present the Time Point Selection (TPS) method that solves this combinatorial problem in a principled and practical way. TPS utilizes expression data from a small set of genes sampled at a high rate. As we show by applying TPS to study mouse lung development, the points selected by TPS can be used to reconstruct an accurate representation for the expression values of the non selected points. Further, even though the selection is only based on gene expression, these points are also appropriate for representing a much larger set of protein, miRNA and DNA methylation changes over time. TPS can thus serve as a key design strategy for high throughput time series experiments. Supporting Website: www.sb.cs.cmu.edu/TPS DOI: http://dx.doi.org/10.7554/eLife.18541.001 PMID:28124972

Study of the photochemical transformation of 2-ethylhexyl 4-(dimethylamino)benzoate (OD-PABA) under conditions relevant to surface waters.

PubMed

Calza, P; Vione, D; Galli, F; Fabbri, D; Dal Bello, F; Medana, C

2016-01-01

We studied the aquatic environmental fate of 2-ethylhexyl 4-(dimethylamino)benzoate (OD-PABA), a widespread sunscreen, to assess its environmental persistence and photoinduced transformation. Direct photolysis is shown to play a key role in phototransformation, and this fast process is expected to be the main attenuation route of OD-PABA in sunlit surface waters. The generation of transformation products (TPs) was followed via HPLC/HRMS. Five (or four) TPs were detected in the samples exposed to UVB (or UVA) radiation, respectively. The main detected TPs of OD-PABA, at least as far as HPLC-HRMS peak areas are concerned, would involve a dealkylation or hydroxylation/oxidation process in both direct photolysis and indirect phototransformation. The latter was simulated by using TiO2-based heterogeneous photocatalysis, involving the formation of nine additional TPs. Most of them resulted from the further degradation of the primary TPs that can also be formed by direct photolysis. Therefore, these secondary TPs might also occur as later transformation intermediates in natural aquatic systems. Copyright © 2015 Elsevier Ltd. All rights reserved.

Reusable LH2 tank technology demonstration through ground test

NASA Technical Reports Server (NTRS)

Bianca, C.; Greenberg, H. S.; Johnson, S. E.

1995-01-01

The paper presents the project plan to demonstrate, by March 1997, the reusability of an integrated composite LH2 tank structure, cryogenic insulation, and thermal protection system (TPS). The plan includes establishment of design requirements and a comprehensive trade study to select the most suitable Reusable Hydrogen Composite Tank system (RHCTS) within the most suitable of 4 candidate structural configurations. The 4 vehicles are winged body with the capability to deliver 25,000 lbs of payload to a circular 220 nm, 51.6 degree inclined orbit (also 40,000 lbs to a 28.5 inclined 150 nm orbit). A prototype design of the selected RHCTS is established to identify the construction, fabrication, and stress simulation and test requirements necessary in an 8 foot diameter tank structure/insulation/TPS test article. A comprehensive development test program supports the 8 foot test article development and involves the composite tank itself, cryogenic insulation, and integrated tank/insulation/TPS designs. The 8 foot diameter tank will contain the integrated cryogenic insulation and TPS designs resulting from this development and that of the concurrent lightweight durable TPS program. Tank ground testing will include 330 cycles of LH2 filling, pressurization, body loading, depressurization, draining, and entry heating.

SU-F-T-399: Migration of Treatment Planning Systems Without Beam Data Measurement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tolakanahalli, R; Tewatia, D

2016-06-15

Purpose: Data acquisition for commissioning is steered by Treatment Planning System (TPS) requirements which can be cumbersome and time consuming involving significant clinic downtime. The purpose of this abstract is to answer if we could circumvent this by extracting data from existing TPS and speed up the process. Methods: Commissioning beam data was obtained from a clinically commissioned TPS (Pinnacle™) using Matlab™ generated Pinnacle™ executable scripts to commission a secondary 3D dose verification TPS (Eclipse™). Profiles and output factors for commissioning as required by Eclipse™ were computed on a 50 cm{sup 3} water phantom at a dose grid resolution ofmore » 2mm3. Verification doses were computed and compared to clinical TPS dose profiles as per TG-106 guidelines. Standard patient plans from Pinnacle™ including IMRT and VMAT plans were re-computed keeping the same monitor units (in order to perform true comparison) using Eclipse™. Computed dose was exported back to Pinnacle for comparison to original plans. This methodology enables us to alleviate all ambiguities that arise in such studies. Results: Profile analysis using in-house software for 6x, showed that for all field sizes including small MLC generated fields, 100% of infield and penumbra data points of Eclipse™ match Pinnacle™ generated and measured profiles with 2%/2 mm gamma criteria. Excellent agreement was observed in the penumbra regions, with all data points passing DTA criteria for complex C-shaped and S-shaped profiles. Patient plan dose volume histograms (DVHs) and isodose lines agreed well to within a 1.5% for target coverage. Conclusion: Secondary 3D dose checking is of utmost importance with advanced techniques such as IMRT and VMAT. Migration of TPS is possible without compromising accuracy or enduring the cumbersome measurement of commissioning data. Economizing time for commissioning such a verification system or for migration of TPS can add great QA value and minimize downtime.« less

Knowledge-based treatment planning and its potential role in the transition between treatment planning systems.

PubMed

Masi, Kathryn; Archer, Paul; Jackson, William; Sun, Yilun; Schipper, Matthew; Hamstra, Daniel; Matuszak, Martha

2017-11-22

Commissioning a new treatment planning system (TPS) involves many time-consuming tasks. We investigated the role that knowledge-based planning (KBP) can play in aiding a clinic's transition to a new TPS. Sixty clinically treated prostate/prostate bed intensity-modulated radiation therapy (IMRT) plans were exported from an in-house TPS and were used to create a KBP model in a newly implemented commercial application. To determine the benefit that KBP may have in a TPS transition, the model was tested on 2 groups of patients. Group 1 consisted of the first 10 prostate/prostate bed patients treated in the commercial TPS after the transition from the in-house TPS. Group 2 consisted of 10 patients planned in the commercial TPS after 8 months of clinical use. The KBP-generated plan was compared with the clinically used plan in terms of plan quality (ability to meet planning objectives and overall dose metrics) and planning efficiency (time required to generate clinically acceptable plans). The KBP-generated plans provided a significantly improved target coverage (p = 0.01) compared with the clinically used plans for Group 1, but yielded plans of comparable target coverage to the clinically used plans for Group 2. For the organs at risk, the KBP-generated plans produced lower doses, on average, for every normal-tissue objective except for the maximum dose to 0.1 cc of rectum. The time needed for the KBP-generated plans ranged from 6 to 15 minutes compared to 30 to 150 and 15 to 60 minutes for manual planning in Groups 1 and 2, respectively. KBP is a promising tool to aid in the transition to a new TPS. Our study indicates that high-quality treatment plans could have been generated in the newly implemented TPS more efficiently compared with not using KBP. Even after 8 months of the clinical use, KBP still showed an increase in plan quality and planning efficiency compared with manual planning. Copyright © 2017 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

A Method of Integrating Aeroheating into Conceptual Reusable Launch Vehicle Design: Evaluation of Advanced Thermal Protection Techniques for Future Reusable Launch Vehicles

NASA Technical Reports Server (NTRS)

Olds, John R.; Cowart, Kris

2001-01-01

A method for integrating Aeroheating analysis into conceptual reusable launch vehicle (RLV) design is presented in this thesis. This process allows for faster turn-around time to converge a RLV design through the advent of designing an optimized thermal protection system (TPS). It consists of the coupling and automation of four computer software packages: MINIVER, TPSX, TCAT, and ADS. MINIVER is an Aeroheating code that produces centerline radiation equilibrium temperatures, convective heating rates, and heat loads over simplified vehicle geometries. These include flat plates and swept cylinders that model wings and leading edges, respectively. TPSX is a NASA Ames material properties database that is available on the World Wide Web. The newly developed Thermal Calculation Analysis Tool (TCAT) uses finite difference methods to carry out a transient in-depth 1-D conduction analysis over the center mold line of the vehicle. This is used along with the Automated Design Synthesis (ADS) code to correctly size the vehicle's thermal protection system (TPS). The numerical optimizer ADS uses algorithms that solve constrained and unconstrained design problems. The resulting outputs for this process are TPS material types, unit thicknesses, and acreage percentages. TCAT was developed for several purposes. First, it provides a means to calculate the transient in-depth conduction seen by the surface of the TPS material that protects a vehicle during ascent and reentry. Along with the in-depth conduction, radiation from the surface of the material is calculated along with the temperatures at the backface and interior parts of the TPS material. Secondly, TCAT contributes added speed and automation to the overall design process. Another motivation in the development of TCAT is optimization. In some vehicles, the TPS accounts for a high percentage of the overall vehicle dry weight. Optimizing the weight of the TPS will thereby lower the percentage of the dry weight accounted for by the TPS. Also, this will lower the cost of the TPS and the overall cost of the vehicle.

Photovoltaic roofing tile systems

NASA Astrophysics Data System (ADS)

Melchior, B.

The integration of photovoltaic (PV) systems in architecture is discussed. A PV-solar roofing tile system with polymer concrete base; PV-roofing tile with elastomer frame profiles and aluminum profile frames; contact technique; and solar cell modules measuring technique are described. Field tests at several places were conducted on the solar generator, electric current behavior, battery station, electric installation, power conditioner, solar measuring system with magnetic bubble memory technique, data transmission via telephone modems, and data processing system. The very favorable response to the PV-compact system proves the commercial possibilities of photovoltaic integration in architecture.

Strategy for good dispersion of well-defined tetrapods in semiconducting polymer matrices.

PubMed

Lim, Jaehoon; Borg, Lisa zur; Dolezel, Stefan; Schmid, Friederike; Char, Kookheon; Zentel, Rudolf

2014-10-01

The morphology or dispersion control in inorganic/organic hybrid systems is studied, which consist of monodisperse CdSe tetrapods (TPs) with grafted semiconducting block copolymers with excess polymers of the same type. Tetrapod arm-length and amount of polymer loading are varied in order to find the ideal morphology for hybrid solar cells. Additionally, polymers without anchor groups are mixed with the TPs to study the effect of such anchor groups on the hybrid morphology. A numerical model is developed and Monte Carlo simulations to study the basis of compatibility or dispersibility of TPs in polymer matrices are performed. The simulations show that bare TPs tend to form clusters in the matrix of excess polymers. The clustering is significantly reduced after grafting polymer chains to the TPs, which is confirmed experimentally. Transmission electron microscopy reveals that the block copolymer-TP mixtures ("hybrids") show much better film qualities and TP distributions within the films when compared with the homopolymer-TP mixtures ("blends"), representing massive aggregations and cracks in the films. This grafting-to approach for the modification of TPs significantly improves the dispersion of the TPs in matrices of "excess" polymers up to the arm length of 100 nm. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evaluation of SRB phenolic TPS material made by an alternate vendor

NASA Technical Reports Server (NTRS)

Karu, Z. S.

1982-01-01

Tests conducted to evaluate the adequacy of solid rocket booster (SRB) phenolic thermal protection system (TPS) material supplied by an alternate vendor chosen by United Space Boosters, Inc. (USBI), to replace the current phenolic TPS sections used thus far on the first four Shuttle flights. The phenolic TPS is applied mainly to the attach and kick rings of the solid rocket booster (SRB). Full-scale sectional models of both the attach and kick ring structure were made up with 0.0265 in. thick stainless steel thin skin covers with thermocouples on them to determine the heating rates. Such models were made up for both the forward and rear faces of the kick ring which has a different configuration on each side. The thin skins were replaced with the alternate phenolic TPS sections cut from flight hardware configuration phenolic parts as supplied by the new vendor. Two tests were performed for each configuration of the attach and kick rings and the samples were exposed to the flow for a duration that gave a heat load equivalent to that obtained in the series of runs made for the current line of phenolic TPS. The samples performed very well with no loss of any phenolic layers. The post-test samples looked better than those used to verify the current phenolic TPS.

SU-F-T-194: Analyzing the Effect of Range Shifter Air Gap On TPS Dose Modeling Accuracy in Superficial PBS Proton Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shirey, R; Wu, H

2016-06-15

Purpose: Treatment planning systems (TPS) may not accurately model superficial dose distributions of range shifted proton pencil beam scanning (PBS) treatments. Numerous patient-specific QA tests performed on superficially treated PBS plans have shown a consistent overestimate of dose by the TPS. This study quantifies variations between TPS planned dose and measured dose as a function of range shifter air gap and treatment depths up to 5 cm. Methods: PBS treatment plans were created in the TPS to uniformly irradiate a volume of solid water. One plan was created for each range shifter position analyzed, and all plans utilized identical dosemore » optimization parameters. Each optimized plan was analyzed in the TPS to determine the planned dose at varying depths. A PBS proton therapy system with a 3.5 cm lucite range shifter delivered the treatment plans, and a parallel plate chamber embedded in RW3 solid water measured dose at shallow depths for each air gap. Differences between measured and planned doses were plotted and analyzed. Results: The data show that the TPS more accurately models superficial dose as the air gap between the range shifter and patient surface decreases. Air gaps less than 10 cm have an average dose difference of only 1.6%, whereas air gaps between 10 and 20 cm differ by 3.0% and gaps greater than 20 cm differ by 4.4%. Conclusion: This study has shown that the TPS is unable to accurately model superficial dose with a large range shifter air gap. Dose differences greater than 3% will likely cause QA failure, as many institutions analyze patient QA with a 3%/3mm gamma analysis. For superficial PBS therapy, range shifter positions should be chosen to keep the air gap less then 10 cm when patient setup and gantry geometry allow.« less

Trehalose-6-phosphate synthase 1 is not the only active TPS in Arabidopsis thaliana.

PubMed

Delorge, Ines; Figueroa, Carlos M; Feil, Regina; Lunn, John E; Van Dijck, Patrick

2015-03-01

Trehalose metabolism is essential for normal growth and development in higher plants. It is synthesized in a two-step pathway catalysed by TPS (trehalose-6-phosphate synthase) and trehalose phosphatase. Arabidopsis thaliana has 11 TPS or TPS-like proteins, which belong to two distinct clades: class I (AtTPS1-AtTPS4) and class II (AtTPS5-AtTPS11). Only AtTPS1 has previously been shown to have TPS activity. A. thaliana tps1∆ mutants fail to complete embryogenesis and rescued lines have stunted growth and delayed flowering, indicating that AtTPS1 is important throughout the life cycle. In the present study, we show that expression of AtTPS2 or AtTPS4 enables the yeast tps1∆ tps2∆ mutant to grow on glucose and accumulate Tre6P (trehalose 6-phosphate) and trehalose. Class II TPS genes did not complement the yeast mutant. Thus A. thaliana has at least three catalytically active TPS isoforms, suggesting that loss of Tre6P production might not be the only reason for the growth defects of A. thaliana tps1 mutants.

Producing the high temperature reusable surface insulation for the thermal protection system of the Space Shuttle

NASA Technical Reports Server (NTRS)

Forgsberg, K.

1979-01-01

The primary insulation system used to protect the space shuttle orbiter on reentry is an externally attached, rigidized, fibrous silica which has been machined into tiles. The tiles constitute the temperature reusable surface insulation system and are used on over 70 percent of the vehicle exterior surface where peak temperatures range from 400 to 1260 C. Cargon-carbon leading edges are used in areas where peak temperatures exceed 1650 C and a felt flexible insulation is used in regions below 400 C. Approximately 32,000 tiles are used in the HRST system and because of vehicle configuration, aerodynamic requirements, and weight considerations no two tiles are alike. Fabrication and quality control procedures are described.

Characterization of particulate and dissolved phosphorus in tile and nearby riverine systems

NASA Astrophysics Data System (ADS)

Jiang, X.; Arai, Y.; David, M.; Gentry, L.

2017-12-01

In the Midwestern U.S., the drainage of agricultural land is predominantly managed by the tile drain system because of its poorly drain properties of clay rich indigenous soils. An accelerated subsurface flow of phosphorus (P) has recently been documented as a primary P transport path in contrast to the typical surface runoff events observed in the Eastern U.S. Recent studies suggested the important role of particulate P (PP) load in agricultural tile drainage water during high flow events. It was hypothesized that PP in the tile water is transported to riverine system contributing to the negative environmental impacts in the Midwestern U.S. In this study, correlation assessment of physicochemical properties of PP in agricultural tile drainage and nearby river samples after a storm event was conducted using a combination of 31P-nuclear magnetic resonance spectroscopy, P K-edge X-ray absorption near edge structure spectroscopy, X-ray diffraction, zetasizer, and transmission electron microscopy. Results show that significantly more colloidal (i.e. 1 nm- 2 µm) and silt-sized (i.e. > 2 µm) particles as well as higher dissolved total P (DTP) and dissolved reactive P (DRP) concentrations existed in river samples than tile samples. Tile and river samples showed similar zeta potential in each particle-size fraction and similar element distributions on colloidal fraction. However, colloidal P concentration and distribution are slightly different between tile and river samples: more colloidal total P and organic P existed in tile colloids than river colloids. The results of P speciation and mineralogical assessment will also be discussed.

TH-D-BRB-04: Pinnacle Scripting: Improving Efficiency While Maintaining Safety

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moore, J.

2016-06-15

Scripting capabilities and application programming interfaces (APIs) are becoming commonly available in modern treatment planning systems. These links to the treatment planning system (TPS) allow users to read data from the TPS, and in some cases use TPS functionality and write data back to the TPS. Such tools are powerful extensions, allowing automation of routine clinical tasks and supporting research, particularly research involving repetitive tasks on large patient populations. The data and functionality exposed by scripting/API capabilities is vendor dependent, as are the languages used by script/API engines, such as the Microsoft .NET framework or Python. Scripts deployed in amore » clinical environment must be commissioned and validated like any other software tool. This session will provide an overview of scripting applications and a discussion of best practices, followed by a practical introduction to the scripting capabilities of three commercial treatment planning systems. Learning Objectives: Understand the scripting capabilities available in several treatment planning systems Learn how to get started using scripting capabilities Understand the best practices for safe script deployment in a clinical environment R. Popple, Varian Medical Systems has provided research support unrelated to the topic of this session.R. Cardan, Varian Medical Systems for grant research, product evaluation, and teaching honorarium.« less

Development of a nondestructive vibration technique for bond assessment of Space Shuttle tiles

NASA Technical Reports Server (NTRS)

Moslehy, Faissal A.

1994-01-01

This final report describes the achievements of the above titled project. The project is funded by NASA-KSC (Grant No. NAG 10-0117) for the period of 1 Jan. to 31 Dec. 1993. The purpose of this project was to develop a nondestructive, noncontact technique based on 'vibration signature' of tile systems to quantify the bond conditions of the thermal protection system) tiles of Space Shuttle orbiters. The technique uses a laser rapid scan system, modal measurements, and finite element modeling. Finite element models were developed for tiles bonded to both clamped and deformable integrated skin-stringer orbiter mid-fuselage. Results showed that the size and location of a disbonded tile can be determined from frequency and mode shape information. Moreover, a frequency response survey was used to quickly identify the disbonded tiles. The finite element results were compared with experimentally determined frequency responses of a 17-tile test panel, where a rapidscan laser system was employed. An excellent degree of correlation between the mathematical simulation and experimental results was realized. An inverse solution for single-tile assemblies was also derived and is being implemented into a computer program that can interact with the modal testing software. The output of the program displays the size and location of disbond. This program has been tested with simulated input (i.e., finite element data), and excellent agreement between predicted and simulated disbonds was shown. Finally, laser vibration imaging and acoustic emission techniques were shown to be well suited for detecting and monitoring the progressive damage in Graphite/Epoxy composite materials.

Analysis of trehalose-6-phosphate synthase (TPS) gene family suggests the formation of TPS complexes in rice.

PubMed

Zang, Baisheng; Li, Haowen; Li, Wenjun; Deng, Xing Wang; Wang, Xiping

2011-08-01

Trehalose-6-phosphate (T6P), an intermediate in the trehalose biosynthesis pathway, is emerging as an important regulator of plant metabolism and development. T6P levels are potentially modulated by a group of trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP) homologues. In this study, we have isolated 11 TPS genes encoding proteins with both TPS and TPP domains, from rice. Functional complement assays performed in yeast tps1 and tps2 mutants, revealed that only OsTPS1 encodes an active TPS enzyme and no OsTPS protein possesses TPP activity. By using a yeast two-hybrid analysis, a complicated interaction network occurred among OsTPS proteins, and the TPS domain might be essential for this interaction to occur. The interaction between OsTPS1 and OsTPS8 in vivo was confirmed by bimolecular fluorescence complementation and coimmunoprecipitation assays. Furthermore, our gel filtration assay showed that there may exist two forms of OsTPS1 (OsTPS1a and OsTPS1b) with different elution profiles in rice. OsTPS1b was particularly cofractionated with OsTPS5 and OsTPS8 in the 360 kDa complex, while OsTPS1a was predominantly incorporated into the complexes larger than 360 kDa. Collectively, these results suggest that OsTPS family members may form trehalose-6-phosphate synthase complexes and therefore potentially modify T6P levels to regulate plant development.

Performance of a Haynes 188 metallic standoff thermal protection system at Mach 7

NASA Technical Reports Server (NTRS)

Avery, D. E.

1981-01-01

A flight weight, metallic thermal protection system (TPS) model applicable to reentry and hypersonic vehicles was subjected to multiple cycles of both radiant and aerothermal heating to evaluate its aerothermal performance and structural integrity. The TPS was designed for a maximum operating temperature of 1255 K and featured a shingled, corrugation stiffened corrugated skin heat shield of Haynes 188, a cobalt base alloy. The model was subjected to 3 radiant preheat/aerothermal tests for a total of 67 seconds and to 15 radiant heating tests for a total of 85.9 minutes at 1255 K. The TPS limited the primary structure to temperatures below 430 K in all tests. No catastrophic failures occurred in the heat shields, supports, or insulation system. The TPS continued to function even after exposure to a differential temperature 4 times the design value produced thermal buckles in the outer skin. The shingled thermal expansion joint effectively allowed for thermal expansion of the heat shield without allowing any appreciable hot gas flow into the model cavity, even though the overlap gap between shields increased after several thermal cycles.

TileDCS web system

NASA Astrophysics Data System (ADS)

Maidantchik, C.; Ferreira, F.; Grael, F.; Atlas Tile Calorimeter Community

2010-04-01

The web system described here provides features to monitor the ATLAS Detector Control System (DCS) acquired data. The DCS is responsible for overseeing the coherent and safe operation of the ATLAS experiment hardware. In the context of the Hadronic Tile Calorimeter Detector (TileCal), it controls the power supplies of the readout electronics acquiring voltages, currents, temperatures and coolant pressure measurements. The physics data taking requires the stable operation of the power sources. The TileDCS Web System retrieves automatically data and extracts the statistics for given periods of time. The mean and standard deviation outcomes are stored as XML files and are compared to preset thresholds. Further, a graphical representation of the TileCal cylinders indicates the state of the supply system of each detector drawer. Colors are designated for each kind of state. In this way problems are easier to find and the collaboration members can focus on them. The user selects a module and the system presents detailed information. It is possible to verify the statistics and generate charts of the parameters over the time. The TileDCS Web System also presents information about the power supplies latest status. One wedge is colored green whenever the system is on. Otherwise it is colored red. Furthermore, it is possible to perform customized analysis. It provides search interfaces where the user can set the module, parameters, and the time period of interest. The system also produces the output of the retrieved data as charts, XML files, CSV and ROOT files according to the user's choice.

Steep-Slope Assembly Testing of Clay and Concrete Tile With and Without Cool Pigmented Colors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, William A

Cool color pigments and sub-tile venting of clay and concrete tile roofs significantly impact the heat flow crossing the roof deck of a steep-slope roof. Field measures for the tile roofs revealed a 70% drop in the peak heat flow crossing the deck as compared to a direct-nailed asphalt shingle roof. The Tile Roofing Institute (TRI) and its affiliate members are keenly interested in documenting the magnitude of the drop for obtaining solar reflectance credits with state and federal "cool roof" building efficiency standards. Tile roofs are direct-nailed or are attached to a deck with batten or batten and counter-battenmore » construction. S-Misson clay and concrete tile roofs, a medium-profile concrete tile roof, and a flat slate tile roof were installed on fully nstrumented attic test assemblies. Temperature measures of the roof, deck, attic, and ceiling, heat flows, solar reflectance, thermal emittance, and the ambient weather were recorded for each of the tile roofs and also on an adjacent attic cavity covered with a conventional pigmented and directnailed asphalt shingle roof. ORNL measured the tile's underside temperature and the bulk air temperature and heat flows just underneath the tile for batten and counter-batten tile systems and compared the results to the conventional asphalt shingle.« less

A design rationale for NASA TileWorld

NASA Technical Reports Server (NTRS)

Philips, Andrew B.; Swanson, Keith J.; Drummond, Mark E.; Bresina, John L.

1991-01-01

Automated systems that can operate in unrestricted real-world domains are still well beyond current computational capabilities. This paper argues that isolating essential problem characteristics found in real-world domains allows for a careful study of how particular control systems operate. By isolating essential problem characteristics and studying their impact on autonomous system performance, we should be able to more quickly deliver systems for practical real-world problems. For our research on planning, scheduling, and control, we have selected three particular domain attributes to study: exogenous events, uncertain action outcome, and metric time. We are not suggesting that studies of these attributes in isolation are sufficient to guarantee the obvious goals of good methodology, brilliant architectures, or first-class results; however, we are suggesting that such isolation facilitates the achievement of these goals. To study these attributes, we have developed the NASA TileWorld. We describe the NASA TileWorld simulator in general terms, present an example NASA TileWorld problem, and discuss some of our motivations and concerns for NASA TileWorld.

Advanced leading edge thermal-structure concept. Direct bond reusable surface insulation to a composite structure

NASA Technical Reports Server (NTRS)

Riccitiello, S. R.; Figueroa, H.; Coe, C. F.; Kuo, C. P.

1984-01-01

An advanced leading-edge concept was analyzed using the space shuttle leading edge system as a reference model. The comparison indicates that a direct-bond system utilizing a high temperature (2700 F) fibrous refractory composite insulation tile bonded to a high temperature (PI/graphite) composite structure can result in a weight savings of up to 800 lb. The concern that tile damage or loss during ascent would result in adverse entry aerodynamics if a leading edge tile system were used is addressed. It was found from experiment that missing tiles (as many as 22) on the leading edge would not significantly affect the basic force-and-moment aerodynamic coefficients. Additionally, this concept affords a degree of redundancy to a thermal protection system in that the base structure (being a composite material) ablates and neither melts nor burns through when subjected to entry heating in the event tiles are actually lost or damaged during ascent.

Design and fabrication of metallic thermal protection systems for aerospace vehicles

NASA Technical Reports Server (NTRS)

Varisco, A.; Bell, P.; Wolter, W.

1978-01-01

A program was conducted to develop a lightweight, efficient metallic thermal protection system (TPS) for application to future shuttle-type reentry vehicles, advanced space transports, and hypersonic cruise vehicles. Technical requirements were generally derived from the space shuttle. A corrugation-stiffened beaded-skin TPS design was used as a baseline. The system was updated and modified to incorporate the latest technology developments and design criteria. The primary objective was to minimize mass for the total system.

Dosimetric inter-institutional comparison in European radiotherapy centres: Results of IAEA supported treatment planning system audit.

PubMed

Gershkevitsh, Eduard; Pesznyak, Csilla; Petrovic, Borislava; Grezdo, Joseph; Chelminski, Krzysztof; do Carmo Lopes, Maria; Izewska, Joanna; Van Dyk, Jacob

2014-05-01

One of the newer audit modalities operated by the International Atomic Energy Agency (IAEA) involves audits of treatment planning systems (TPS) in radiotherapy. The main focus of the audit is the dosimetry verification of the delivery of a radiation treatment plan for three-dimensional (3D) conformal radiotherapy using high energy photon beams. The audit has been carried out in eight European countries - Estonia, Hungary, Latvia, Lithuania, Serbia, Slovakia, Poland and Portugal. The corresponding results are presented. The TPS audit reviews the dosimetry, treatment planning and radiotherapy delivery processes using the 'end-to-end' approach, i.e. following the pathway similar to that of the patient, through imaging, treatment planning and dose delivery. The audit is implemented at the national level with IAEA assistance. The national counterparts conduct the TPS audit at local radiotherapy centres through on-site visits. TPS calculated doses are compared with ion chamber measurements performed in an anthropomorphic phantom for eight test cases per algorithm/beam. A set of pre-defined agreement criteria is used to analyse the performance of TPSs. TPS audit was carried out in 60 radiotherapy centres. In total, 190 data sets (combination of algorithm and beam quality) have been collected and reviewed. Dosimetry problems requiring interventions were discovered in about 10% of datasets. In addition, suboptimal beam modelling in TPSs was discovered in a number of cases. The TPS audit project using the IAEA methodology has verified the treatment planning system calculations for 3D conformal radiotherapy in a group of radiotherapy centres in Europe. It contributed to achieving better understanding of the performance of TPSs and helped to resolve issues related to imaging, dosimetry and treatment planning.

High-temperature behavior of advanced spacecraft TPS

NASA Technical Reports Server (NTRS)

Pallix, Joan

1994-01-01

The objective of this work has been to develop more efficient, lighter weight, and higher temperature thermal protection systems (TPS) for future reentry space vehicles. The research carried out during this funding period involved the design, analysis, testing, fabrication, and characterization of thermal protection materials to be used on future hypersonic vehicles. This work is important for the prediction of material performance at high temperature and aids in the design of thermal protection systems for a number of programs including programs such as the National Aerospace Plane (NASP), Pegasus and Pegasus/SWERVE, the Comet Rendezvous and Flyby Vehicle (CRAF), and the Mars mission entry vehicles. Research has been performed in two main areas including development and testing of thermal protection systems (TPS) and computational research. A variety of TPS materials and coatings have been developed during this funding period. Ceramic coatings were developed for flexible insulations as well as for low density ceramic insulators. Chemical vapor deposition processes were established for the fabrication of ceramic matrix composites. Experimental testing and characterization of these materials has been carried out in the NASA Ames Research Center Thermophysics Facilities and in the Ames time-of-flight mass spectrometer facility. By means of computation, we have been better able to understand the flow structure and properties of the TPS components and to estimate the aerothermal heating, stress, ablation rate, thermal response, and shape change on the surfaces of TPS. In addition, work for the computational surface thermochemistry project has included modification of existing computer codes and creating new codes to model material response and shape change on atmospheric entry vehicles in a variety of environments (e.g., earth and Mars atmospheres).

High-temperature behavior of advanced spacecraft TPS

NASA Astrophysics Data System (ADS)

Pallix, Joan

1994-05-01

The objective of this work has been to develop more efficient, lighter weight, and higher temperature thermal protection systems (TPS) for future reentry space vehicles. The research carried out during this funding period involved the design, analysis, testing, fabrication, and characterization of thermal protection materials to be used on future hypersonic vehicles. This work is important for the prediction of material performance at high temperature and aids in the design of thermal protection systems for a number of programs including programs such as the National Aerospace Plane (NASP), Pegasus and Pegasus/SWERVE, the Comet Rendezvous and Flyby Vehicle (CRAF), and the Mars mission entry vehicles. Research has been performed in two main areas including development and testing of thermal protection systems (TPS) and computational research. A variety of TPS materials and coatings have been developed during this funding period. Ceramic coatings were developed for flexible insulations as well as for low density ceramic insulators. Chemical vapor deposition processes were established for the fabrication of ceramic matrix composites. Experimental testing and characterization of these materials has been carried out in the NASA Ames Research Center Thermophysics Facilities and in the Ames time-of-flight mass spectrometer facility. By means of computation, we have been better able to understand the flow structure and properties of the TPS components and to estimate the aerothermal heating, stress, ablation rate, thermal response, and shape change on the surfaces of TPS. In addition, work for the computational surface thermochemistry project has included modification of existing computer codes and creating new codes to model material response and shape change on atmospheric entry vehicles in a variety of environments (e.g., earth and Mars atmospheres).

Solar photocatalytic oxidation of recalcitrant natural metabolic by-products of amoxicillin biodegradation.

PubMed

Pereira, João H O S; Reis, Ana C; Homem, Vera; Silva, José A; Alves, Arminda; Borges, Maria T; Boaventura, Rui A R; Vilar, Vítor J P; Nunes, Olga C

2014-11-15

The contamination of the aquatic environment by non-metabolized and metabolized antibiotic residues has brought the necessity of alternative treatment steps to current water decontamination technologies. This work assessed the feasibility of using a multistage treatment system for amoxicillin (AMX) spiked solutions combining: i) a biological treatment process using an enriched culture to metabolize AMX, with ii) a solar photocatalytic system to achieve the removal of the metabolized transformation products (TPs) identified via LC-MS, recalcitrant to further biological degradation. Firstly, a mixed culture (MC) was obtained through the enrichment of an activated sludge sample collected in an urban wastewater treatment plant (WWTP). Secondly, different aqueous matrices spiked with AMX were treated with the MC and the metabolic transformation products were identified. Thirdly, the efficiency of two solar assisted photocatalytic processes (TiO2/UV or Fe(3+)/Oxalate/H2O2/UV-Vis) was assessed in the degradation of the obtained TPs using a lab-scale prototype photoreactor equipped with a compound parabolic collector (CPC). Highest AMX specific biodegradation rates were obtained in buffer and urban wastewater (WW) media (0.10 ± 0.01 and 0.13 ± 0.07 g(AMX) g(biomass)(-1) h(-1), respectively). The resulting TPs, which no longer presented antibacterial activity, were identified as amoxicilloic acid (m/z = 384). The performance of the Fe(3+)/Oxalate/H2O2/UV-Vis system in the removal of the TPs from WW medium was superior to the TiO2/UV process (TPs no longer detected after 40 min (QUV = 2.6 kJ L(-1)), against incomplete TPs removal after 240 min (QUV = 14.9 kJ L(-1)), respectively). Copyright © 2014 Elsevier Ltd. All rights reserved.

Additive roles of two TPS genes in trehalose synthesis, conidiation, multiple stress responses and host infection of a fungal insect pathogen.

PubMed

Wang, Juan-Juan; Cai, Qing; Qiu, Lei; Ying, Sheng-Hua; Feng, Ming-Guang

2017-05-01

Intracellular trehalose accumulation is relevant to fungal life and pathogenicity. Trehalose-6-phosphate synthase (TPS) is known to control the first step of trehalose synthesis, but functions of multiple TPS genes in some filamentous fungi are variable. Here, we examined the functions of two TPS genes (tpsA and tpsB) in Beauveria bassiana, a fungal insect pathogen widely applied in arthropod pest control. Intracellular TPS activity and trehalose content decreased by 71-75 and 72-80% in ΔtpsA, and 21-30 and 15-45% in ΔtpsB, respectively, and to undetectable levels in ΔtpsAΔtpsB, under normal and stressful conditions. The three mutants lost 33, 50, and 98% of conidiation capacity in standard cultures. Conidial quality indicated by viability, density, intracellular trehalose content, cell wall integrity, and hydrophobicity was more impaired in ΔtpsA than in ΔtpsB and mostly in ΔtpsAΔtpsB, which was also most sensitive to nutritional, chemical, and environmental stresses and least virulent to Galleria mellonella larvae. Almost all of phenotypic defects in ΔtpsAΔtpsB approached to the sums of those observed in ΔtpsA and ΔtpsB and were restored by targeted gene complementation. Altogether, TpsA and TpsB play complementary roles in sustaining trehalose synthesis, conidiation capacity, conidial quality, multiple stress tolerance, and virulence, highlighting a significance of both for the fungal adaptation to environment and host.

Determination of Acreage Thermal Protection Foam Loss From Ice and Foam Impacts

NASA Technical Reports Server (NTRS)

Carney, Kelly S.; Lawrence, Charles

2015-01-01

A parametric study was conducted to establish Thermal Protection System (TPS) loss from foam and ice impact conditions similar to what might occur on the Space Launch System. This study was based upon the large amount of testing and analysis that was conducted with both ice and foam debris impacts on TPS acreage foam for the Space Shuttle Project External Tank. Test verified material models and modeling techniques that resulted from Space Shuttle related testing were utilized for this parametric study. Parameters varied include projectile mass, impact velocity and impact angle (5 degree and 10 degree impacts). The amount of TPS acreage foam loss as a result of the various impact conditions is presented.

Potential risks from UV/H2O2 oxidation and UV photocatalysis: A review of toxic, assimilable, and sensory-unpleasant transformation products.

PubMed

Wang, Wen-Long; Wu, Qian-Yuan; Huang, Nan; Xu, Zi-Bin; Lee, Min-Yong; Hu, Hong-Ying

2018-05-15

UV based advanced oxidation processes (UV-AOPs) that efficiently eliminate organic pollutants during water treatment have been the subject of numerous investigations. Most organic pollutants are not completely mineralized during UV-AOPs but are partially oxidized into transformation products (TPs), thereby adding complexity to the treated water and posing risks to humans, ecological systems, and the environment. While the degradation kinetics and mechanisms of pollutants have been widely documented, there is little information about the risks associated with TPs. In this review, we have collated recent knowledge about the harmful TPs that are generated in UV/H 2 O 2 and UV photocatalysis, two UV-AOPs that have been studied extensively. Toxic and assimilable TPs were ubiquitously observed in more than 80% of UV-AOPs of organic pollutants, of which the toxicity and assimilability levels changed with variations in the reaction conditions, such as the UV fluence and oxidant dosage. Previous studies and modeling assessments showed that toxic and assimilable TPs may be generated during hydroxylation, dealkylation, decarboxylation, and deamination. Among various reactions, TPs generated from dealkylation and decarboxylation were generally less and more toxic than the parent pollutants, respectively; TPs generated from decarboxylation and deamination were generally less and more assimilable than the parent pollutants, respectively. There is also potential concern about the sensory-unpleasant TPs generated by oxidations and subsequent metabolism of microorganisms. In this overview, we stress the need to include both the concentrations of organic pollutants and the evaluations of the risks from TPs for the quality assessments of the water treated by UV-AOPs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Advanced High-Temperature Flexible TPS for Inflatable Aerodynamic Decelerators

NASA Technical Reports Server (NTRS)

DelCorso, Joseph A.; Cheatwood, F. McNeil; Bruce, Walter E., III; Hughes, Stephen J.; Calomino, Anthony M.

2011-01-01

Typical entry vehicle aeroshells are limited in size by the launch vehicle shroud. Inflatable aerodynamic decelerators allow larger aeroshell diameters for entry vehicles because they are not constrained to the launch vehicle shroud diameter. During launch, the hypersonic inflatable aerodynamic decelerator (HIAD) is packed in a stowed configuration. Prior to atmospheric entry, the HIAD is deployed to produce a drag device many times larger than the launch shroud diameter. The large surface area of the inflatable aeroshell provides deceleration of high-mass entry vehicles at relatively low ballistic coefficients. Even for these low ballistic coefficients there is still appreciable heating, requiring the HIAD to employ a thermal protection system (TPS). This TPS must be capable of surviving the heat pulse, and the rigors of fabrication handling, high density packing, deployment, and aerodynamic loading. This paper provides a comprehensive overview of flexible TPS tests and results, conducted over the last three years. This paper also includes an overview of each test facility, the general approach for testing flexible TPS, the thermal analysis methodology and results, and a comparison with 8-foot High Temperature Tunnel, Laser-Hardened Materials Evaluation Laboratory, and Panel Test Facility test data. Results are presented for a baseline TPS layup that can withstand a 20 W/cm2 heat flux, silicon carbide (SiC) based TPS layup, and polyimide insulator TPS layup. Recent work has focused on developing material layups expected to survive heat flux loads up to 50 W/cm2 (which is adequate for many potential applications), future work will consider concepts capable of withstanding more than 100 W/cm2 incident radiant heat flux. This paper provides an overview of the experimental setup, material layup configurations, facility conditions, and planned future flexible TPS activities.

Thermal insulation attaching means. [adhesive bonding of felt vibration insulators under ceramic tiles

NASA Technical Reports Server (NTRS)

Leger, L. J. (Inventor)

1978-01-01

An improved isolation system is provided for attaching ceramic tiles of insulating material to the surface of a structure to be protected against extreme temperatures of the nature expected to be encountered by the space shuttle orbiter. This system isolates the fragile ceramic tiles from thermally and mechanically induced vehicle structural strains. The insulating tiles are affixed to a felt isolation pad formed of closely arranged and randomly oriented fibers by means of a flexible adhesive and in turn the felt pad is affixed to the metallic vehicle structure by an additional layer of flexible adhesive.

Thermal Protection Materials and Systems: Past, Present, and Future

NASA Technical Reports Server (NTRS)

Johnson, Sylvia M.

2013-01-01

Thermal protection materials and systems (TPS) protect vehicles from the heat generated when entering a planetary atmosphere. NASA has developed many TPS systems over the years for vehicle ranging from planetary probes to crewed vehicles. The goal for all TPS is efficient and reliable performance. Efficient means using the right material for the environment and minimizing the mass of the heat shield without compromising safety. Efficiency is critical if the payload such as science experiments is to be maximized on a particular vehicle. Reliable means that we understand and can predict performance of the material. Although much characterization and testing of materials is performed to qualify and certify them for flight, it is not possible to completely recreate the reentry conditions in test facilities, and flight-testing

Infra-red and vibration tests of hybrid ablative/ceramic matrix technological breadboards for earth re-entry thermal protection systems

NASA Astrophysics Data System (ADS)

Barcena, Jorge; Garmendia, Iñaki; Triantou, Kostoula; Mergia, Konstatina; Perez, Beatriz; Florez, Sonia; Pinaud, Gregory; Bouilly, Jean-Marc; Fischer, Wolfgang P. P.

2017-05-01

A new thermal protection system for atmospheric earth re-entry is proposed. This concept combines the advantages of both reusable and ablative materials to establish a new hybrid concept with advanced capabilities. The solution consists of the design and the integration of a dual shield resulting on the overlapping of an external thin ablative layer with a Ceramic Matrix Composite (CMC) thermo-structural core. This low density ablative material covers the relatively small heat peak encountered during re-entry the CMC is not able to bear. On the other hand the big advantage of the CMC based TPS is of great benefit which can deal with the high integral heat for the bigger time period of the re-entry. To verify the solution a whole testing plan is envisaged, which as part of it includes thermal shock test by infra-red heating (heating flux up to 1 MW/m2) and vibration test under launcher conditions (Volna and Ariane 5). Sub-scale tile samples (100×100 mm2) representative of the whole system (dual ablator/ceramic layers, insulation, stand-offs) are specifically designed, assembled and tested (including the integration of thermocouples). Both the thermal and the vibration test are analysed numerically by simulation tools using Finite Element Models. The experimental results are in good agreement with the expected calculated parameters and moreover the solution is qualified according to the specified requirements.

Flutter Analysis of the Thermal Protection Layer on the NASA HIAD

NASA Technical Reports Server (NTRS)

Goldman, Benjamin D.; Dowell, Earl H.; Scott, Robert C.

2013-01-01

A combination of classical plate theory and a supersonic aerodynamic model is used to study the aeroelastic flutter behavior of a proposed thermal protection system (TPS) for the NASA HIAD. The analysis pertains to the rectangular configurations currently being tested in a NASA wind-tunnel facility, and may explain why oscillations of the articles could be observed. An analysis using a linear flat plate model indicated that flutter was possible well within the supersonic flow regime of the wind tunnel tests. A more complex nonlinear analysis of the TPS, taking into account any material curvature present due to the restraint system or substructure, indicated that significantly greater aerodynamic forcing is required for the onset of flutter. Chaotic and periodic limit cycle oscillations (LCOs) of the TPS are possible depending on how the curvature is imposed. When the pressure from the base substructure on the bottom of the TPS is used as the source of curvature, the flutter boundary increases rapidly and chaotic behavior is eliminated.

Thermal Protection System Application to Composite Cryotank Technology Demonstrator

NASA Technical Reports Server (NTRS)

Protz, Alison; Nettles, Mindy

2015-01-01

The EM41 Thermal Protection System (TPS) team contributed to the success of the Composite Cryotank Technology Demonstrator (CCTD) manufacturing by developing and implementing a low-cost solution to apply cryoinsulation foam on the exterior surface of the tank in the NASA Marshall Space Flight Center (MSFC) TPS Development Facility, Bldg. 4765. The TPS team used techniques developed for the smallscale composite cryotank to apply Stepanfoam S-180 polyurethane foam to the 5.5-meter CCTD using a manual spray process. Manual spray foam technicians utilized lifts and scaffolding to access the barrel and dome sections of the large-scale tank in the horizontal orientation. During manufacturing, the tank was then oriented vertically, allowing access to the final barrel section for manual spray foam application. The CCTD was the largest application of manual spray foam performed to date with the S-180 polyurethane foam and required the TPS team to employ best practices for process controls on the development article.

Molecular Evolution of Trehalose-6-Phosphate Synthase (TPS) Gene Family in Populus, Arabidopsis and Rice

PubMed Central

Yang, Hai-Ling; Liu, Yan-Jing; Wang, Cai-Ling; Zeng, Qing-Yin

2012-01-01

Trehalose-6-phosphate synthase (TPS) plays important roles in trehalose metabolism and signaling. Plant TPS proteins contain both a TPS and a trehalose-6-phosphate phosphatase (TPP) domain, which are coded by a multi-gene family. The plant TPS gene family has been divided into class I and class II. A previous study showed that the Populus, Arabidopsis, and rice genomes have seven class I and 27 class II TPS genes. In this study, we found that all class I TPS genes had 16 introns within the protein-coding region, whereas class II TPS genes had two introns. A significant sequence difference between the two classes of TPS proteins was observed by pairwise sequence comparisons of the 34 TPS proteins. A phylogenetic analysis revealed that at least seven TPS genes were present in the monocot–dicot common ancestor. Segmental duplications contributed significantly to the expansion of this gene family. At least five and three TPS genes were created by segmental duplication events in the Populus and rice genomes, respectively. Both the TPS and TPP domains of 34 TPS genes have evolved under purifying selection, but the selective constraint on the TPP domain was more relaxed than that on the TPS domain. Among 34 TPS genes from Populus, Arabidopsis, and rice, four class I TPS genes (AtTPS1, OsTPS1, PtTPS1, and PtTPS2) were under stronger purifying selection, whereas three Arabidopsis class I TPS genes (AtTPS2, 3, and 4) apparently evolved under relaxed selective constraint. Additionally, a reverse transcription polymerase chain reaction analysis showed the expression divergence of the TPS gene family in Populus, Arabidopsis, and rice under normal growth conditions and in response to stressors. Our findings provide new insights into the mechanisms of gene family expansion and functional evolution. PMID:22905132

Molecular evolution of trehalose-6-phosphate synthase (TPS) gene family in Populus, Arabidopsis and rice.

PubMed

Yang, Hai-Ling; Liu, Yan-Jing; Wang, Cai-Ling; Zeng, Qing-Yin

2012-01-01

Trehalose-6-phosphate synthase (TPS) plays important roles in trehalose metabolism and signaling. Plant TPS proteins contain both a TPS and a trehalose-6-phosphate phosphatase (TPP) domain, which are coded by a multi-gene family. The plant TPS gene family has been divided into class I and class II. A previous study showed that the Populus, Arabidopsis, and rice genomes have seven class I and 27 class II TPS genes. In this study, we found that all class I TPS genes had 16 introns within the protein-coding region, whereas class II TPS genes had two introns. A significant sequence difference between the two classes of TPS proteins was observed by pairwise sequence comparisons of the 34 TPS proteins. A phylogenetic analysis revealed that at least seven TPS genes were present in the monocot-dicot common ancestor. Segmental duplications contributed significantly to the expansion of this gene family. At least five and three TPS genes were created by segmental duplication events in the Populus and rice genomes, respectively. Both the TPS and TPP domains of 34 TPS genes have evolved under purifying selection, but the selective constraint on the TPP domain was more relaxed than that on the TPS domain. Among 34 TPS genes from Populus, Arabidopsis, and rice, four class I TPS genes (AtTPS1, OsTPS1, PtTPS1, and PtTPS2) were under stronger purifying selection, whereas three Arabidopsis class I TPS genes (AtTPS2, 3, and 4) apparently evolved under relaxed selective constraint. Additionally, a reverse transcription polymerase chain reaction analysis showed the expression divergence of the TPS gene family in Populus, Arabidopsis, and rice under normal growth conditions and in response to stressors. Our findings provide new insights into the mechanisms of gene family expansion and functional evolution.

Dynamic and Static High Temperature Resistant Ceramic Seals for X- 38 re-Entry Vehicle

NASA Astrophysics Data System (ADS)

Handrick, Karin E.; Curry, Donald M.

2002-01-01

In a highly successful partnership, NAS A, ESA, DLR (German Space Agency) and European industry are building the X-38, V201 re-entry spacecraft, the prototype of the International Space Station's Crew Return Vehicle (CRV). This vehicle would serve both as an ambulance for medical emergencies and as an evacuation vehicle for the Space Station. The development of essential systems and technologies for a reusable re-entry vehicle is a first for Europe, and sharing the development of an advanced re-entry spacecraft with foreign partners is a first for NASA. NASA, in addition to its subsystem responsibilities, is performing overall X-38 vehicle system engineering and integration, will launch V201 on the Space Shuttle, deliver flight data for post-flight analysis and assessment and is responsible for development and manufacture of structural vehicle components and thermal protection (TPS) tiles. The major European objective for cooperation with NASA on X-38 was to establish a clear path through which key technologies needed for future space transportation systems could be developed and validated at affordable cost and with controlled risk. Europe has taken the responsibility to design and manufacture hot control surfaces like metallic rudders and ceramic matrix composites (CMC) body flaps, thermal protection systems such as CMC leading edges, the CMC nose cap and -skirt, insulation, landing gears and elements of the V201 primary structure. Especially hot control surfaces require extremely high temperature resistant seals to limit hot gas ingestion and transfer of heat to underlying low-temperature structures to prevent overheating of these structures and possible loss of the vehicle. Complex seal interfaces, which have to fulfill various, tight mission- and vehicle-related requirements exist between the moveable ceramic body flaps and the bottom surface of the vehicle, between the rudder and fin structure and the ceramic leading edge panel and TPS tiles. While NASA concentrated on the development, qualification and manufacture of dynamic seals in the rudder area, the responsibility of MAN Technologie focused on the development, lay-out, qualification and flight hardware manufacture of static and dynamic seals in ceramic hot structures' associated gaps and interfaces, dealing with re-entry temperatures up to 1600°C. This paper presents results for temperature and mechanical stability, flow, scrub (up to 1000 cycles) and of arc jet tests under representative low boundary conditions and plasma step/gap tests, conducted during the development and qualification phases of these different kind of ceramic seals. Room temperature seal compression tests were performed at low compression levels to determine load versus linear compression, preload, contact area, stiffness and resiliency characteristics under low load conditions. Flow tests with thermally aged seals were conducted at ambient temperature to examine leakage at low compression levels and in as-manufactured conditions. Seal scrub tests were performed to examine durability and wear resistance and to recommend surface treatments required to maximize seal wear life. Results of arc jet/plasma tests under simulated re-entry conditions (pressure, temperature) verified seal temperature stability and function under representative assembly and interface conditions. Each of these specifically developed seals fulfilled the requirements and is qualified for flight on X-38, V201.

Terra-Preta-Technology as an innovative system component to create circulation oriented, sustainable land use systems

NASA Astrophysics Data System (ADS)

Dotterweich, M.; Böttcher, J.; Krieger, A.

2012-04-01

This paper presents current research and application projects on innovative system solutions which are based on the implementation of a regional resource efficient material flow management as well as utilising "Terra-Preta-Technology" as an innovative system component. Terra Preta Substrate (TPS) is a recently developed substance composed of liquid and solid organic matter, including biochar, altered by acid-lactic fermentation. Based on their properties, positive effects on water and nutrient retention, soil microbiological activity, and cation-exchange capacity are expected and currently investigated by different projects. TPS further sequesters carbon and decreases NO2 emissions from fertilized soils as observed by the use of biochar. The production of TPS is based on a circulation oriented organic waste management system directly adapted to the local available inputs and desired soil amendment properties. The production of TPS is possible with simple box systems for subsistence farming but also on a much larger scale as modular industrial plants for farmers or commercial and municipal waste management companies in sizes from 500 and 50,000 m3. The Terra-Preta-Technology enhances solutions to soil conservation, soil amelioration, humic formation, reduced water consumption, long term carbon sequestration, nutrient retention, containment binding, and to biodiversity on local to a regional scale. The projects also involve research of ancient land management systems to enhance resource efficiency by means of an integrative and transdisciplinary approach.

A portable high-power diode laser-based single-stage ceramic tile grout sealing system

NASA Astrophysics Data System (ADS)

Lawrence, J.; Schmidt, M. J. J.; Li, L.; Edwards, R. E.; Gale, A. W.

2002-02-01

By means of a 60 W high-power diode laser (HPDL) and a specially developed grout material the void between adjoining ceramic tiles has been successfully sealed. A single-stage process has been developed which uses a crushed ceramic tile mix to act as a tough, inexpensive bulk substrate and a glazed enamel surface to provide an impervious surface glaze. The single-stage ceramic tile grout sealing process yielded seals produced in normal atmospheric conditions that displayed no discernible cracks and porosities. The single-stage grout is simple to formulate and easy to apply. Tiles were successfully sealed with power densities as low as 200 kW/ mm2 and at rates of up to 600 mm/ min. Bonding of the enamel to the crushed ceramic tile mix was identified as being primarily due to van der Waals forces and, on a very small scale, some of the crushed ceramic tile mix material dissolving into the glaze. In terms of mechanical, physical and chemical characteristics, the single-stage ceramic tile grout was found to be far superior to the conventional epoxy tile grout and, in many instances, matched and occasionally surpassed that of the ceramic tiles themselves. What is more, the development of a hand-held HPDL beam delivery unit and the related procedures necessary to lead to the commercialisation of the single-stage ceramic tile grout sealing process are presented. Further, an appraisal of the potential hazards associated with the use of the HPDL in an industrial environment and the solutions implemented to ensure that the system complies with the relevant safety standards are given.

Tile drainage phosphorus loss with long-term consistent cropping systems and fertilization.

PubMed

Zhang, T Q; Tan, C S; Zheng, Z M; Drury, C F

2015-03-01

Phosphorus (P) loss in tile drainage water may vary with agricultural practices, and the impacts are often hard to detect with short-term studies. We evaluated the effects of long-term (≥43 yr) cropping systems (continuous corn [CC], corn-oats-alfalfa-alfalfa rotation [CR], and continuous grass [CS]) and fertilization (fertilization [F] vs. no-fertilization [NF]) on P loss in tile drainage water from a clay loam soil over a 4-yr period. Compared with NF, long-term fertilization increased concentrations and losses of dissolved reactive P (DRP), dissolved unreactive P (DURP), and total P (TP) in tile drainage water, with the increments following the order: CS > CR > CC. Dissolved P (dissolved reactive P [DRP] and dissolved unreactive P [DURP]) was the dominant P form in drainage outflow, accounting for 72% of TP loss under F-CS, whereas particulate P (PP) was the major form of TP loss under F-CC (72%), F-CR (62%), NF-CS (66%), NF-CC (74%), and NF-CR (72%). Dissolved unreactive P played nearly equal roles as DRP in P losses in tile drainage water. Stepwise regression analysis showed that the concentration of P (DRP, DURP, and PP) in tile drainage flow, rather than event flow volume, was the most important factor contributing to P loss in tile drainage water, although event flow volume was more important in PP loss than in dissolved P loss. Continuous grass significantly increased P loss by increasing P concentration and flow volume of tile drainage water, especially under the fertilization treatment. Long-term grasslands may become a significant P source in tile-drained systems when they receive regular P addition. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Thermal performance of a customized multilayer insulation (MLI)

NASA Technical Reports Server (NTRS)

Leonhard, K. E.

1976-01-01

The thermal performance of a LH2 tank on a shroudless vehicle was investigated. The 1.52 m (60 in) tank was insulated with 2 MLI blankets consisting of 18 double aluminized Mylar radiation shields and 19 silk net spacers. The temperature of outer space was simulated by using a cryoshroud which was maintained at near liquid hydrogen temperature. The heating effects of a payload were simulated by utilizing a thermal payload simulator (TPS) viewing the tank. The test program consisted of three major test categories: (1) null testing, (2) thermal performance testing of the tank installed MLI system, and (3) thermal testing of a customized MLI configuration. TPS surface temperatures during the null test were maintained at near hydrogen temperature and during test categories 2 and 3 at 289 K (520R). The heat flow rate through the tank installed MLI at a tank/TPS spacing of 0.457 m was 1.204 watts with no MLI on the TPS and 0.059 watts through the customized MLI with three blankets on the TPS. Reducing the tank/TPS spacing from 0.457 m to 0.152 m the heat flow through the customized MLI increased by 10 percent.

Effect of stearic acid-grafted starch compatibilizer on properties of linear low density polyethylene/thermoplastic starch blown film.

PubMed

Khanoonkon, Nattaporn; Yoksan, Rangrong; Ogale, Amod A

2016-02-10

The present work aims to investigate the effect of stearic acid-grafted starch (ST-SA) on the rheological, thermal, optical, dynamic mechanical thermal, and tensile properties of linear low density polyethylene/thermoplastic starch (LLDPE/TPS) blends, as well as on their water vapor and oxygen barrier properties. Blends consisting of LLDPE and TPS in a weight ratio of 60:40 and ST-SA at different concentrations, i.e. 1, 3 and 5%, were prepared using a twin-screw extruder. The obtained resins were subsequently converted into films via blown film extrusion. Incorporation of ST-SA resulted in a decreased degree of shear thinning, reduced ambient temperature elasticity, and improved tensile strength, secant modulus, extensibility, and UV absorption, as well as diminished water vapor and oxygen permeabilities of the LLDPE/TPS blend. These effects are attributed to the enhanced interfacial adhesion between LLDPE and TPS phases through the compatibilizing effect induced by ST-SA, and the good dispersion of the TPS phase in the LLDPE matrix. The results confirmed that ST-SA could potentially be used as a compatibilizer for the LLDPE/TPS blend system. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thermal protection system development, testing, and qualification for atmospheric probes and sample return missions. Examples for Saturn, Titan and Stardust-type sample return

NASA Astrophysics Data System (ADS)

Venkatapathy, E.; Laub, B.; Hartman, G. J.; Arnold, J. O.; Wright, M. J.; Allen, G. A.

2009-07-01

The science community has continued to be interested in planetary entry probes, aerocapture, and sample return missions to improve our understanding of the Solar System. As in the case of the Galileo entry probe, such missions are critical to the understanding not only of the individual planets, but also to further knowledge regarding the formation of the Solar System. It is believed that Saturn probes to depths corresponding to 10 bars will be sufficient to provide the desired data on its atmospheric composition. An aerocapture mission would enable delivery of a satellite to provide insight into how gravitational forces cause dynamic changes in Saturn's ring structure that are akin to the evolution of protoplanetary accretion disks. Heating rates for the "shallow" Saturn probes, Saturn aerocapture, and sample Earth return missions with higher re-entry speeds (13-15 km/s) from Mars, Venus, comets, and asteroids are in the range of 1-6 KW/cm 2. New, mid-density thermal protection system (TPS) materials for such probes can be mission enabling for mass efficiency and also for use on smaller vehicles enabled by advancements in scientific instrumentation. Past consideration of new Jovian multiprobe missions has been considered problematic without the Giant Planet arcjet facility that was used to qualify carbon phenolic for the Galileo probe. This paper describes emerging TPS technologies and the proposed use of an affordable, small 5 MW arcjet that can be used for TPS development, in test gases appropriate for future planetary probe and aerocapture applications. Emerging TPS technologies of interest include new versions of the Apollo Avcoat material and a densified variant of Phenolic Impregnated Carbon Ablator (PICA). Application of these and other TPS materials and the use of other facilities for development and qualification of TPS for Saturn, Titan, and Sample Return missions of the Stardust class with entry speeds from 6.0 to 28.6 km/s are discussed.

Thermal support for scale support

NASA Technical Reports Server (NTRS)

Dean, W. G.

1976-01-01

The thermal design work completed for the Thermal Protection System (TPS) of the Space Shuttle System (TPS) of the space shuttle vehicle was documented. This work was divided into three phases, the first two of which reported in previous documents. About 22 separate tasks were completed in phase III, such as: hot gas facility (HGF) support, guarded tank support, shuttle external tank (ET) thermal design handbook support, etc.

Nonlinear Aeroelastic Analysis of the HIAD TPS Coupon in the NASA 8' High Temperature Tunnel: Theory and Experiment

NASA Technical Reports Server (NTRS)

Goldman, Benjamin D.; Scott, Robert C,; Dowell, Earl H.

2014-01-01

The purpose of this work is to develop a set of theoretical and experimental techniques to characterize the aeroelasticity of the thermal protection system (TPS) on the NASA Hypersonic Inflatable Aerodynamic Decelerator (HIAD). A square TPS coupon experiences trailing edge oscillatory behavior during experimental testing in the 8' High Temperature Tunnel (HTT), which may indicate the presence of aeroelastic flutter. Several theoretical aeroelastic models have been developed, each corresponding to a different experimental test configuration. Von Karman large deflection theory is used for the plate-like components of the TPS, along with piston theory for the aerodynamics. The constraints between the individual TPS layers and the presence of a unidirectional foundation at the back of the coupon are included by developing the necessary energy expressions and using the Rayleigh Ritz method to derive the nonlinear equations of motion. Free vibrations and limit cycle oscillations are computed and the frequencies and amplitudes are compared with accelerometer and photogrammetry data from the experiments.

SU-F-T-364: Monte Carlo-Dose Verification of Volumetric Modulated Arc Therapy Plans Using AAPM TG-119 Test Patterns

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onizuka, R; Araki, F; Ohno, T

2016-06-15

Purpose: To investigate the Monte Carlo (MC)-based dose verification for VMAT plans by a treatment planning system (TPS). Methods: The AAPM TG-119 test structure set was used for VMAT plans by the Pinnacle3 (convolution/superposition), using a Synergy radiation head of a 6 MV beam with the Agility MLC. The Synergy was simulated with the EGSnrc/BEAMnrc code, and VMAT dose distributions were calculated with the EGSnrc/DOSXYZnrc code by the same irradiation conditions as TPS. VMAT dose distributions of TPS and MC were compared with those of EBT3 film, by 2-D gamma analysis of ±3%/3 mm criteria with a threshold of 30%more » of prescribed doses. VMAT dose distributions between TPS and MC were also compared by DVHs and 3-D gamma analysis of ±3%/3 mm criteria with a threshold of 10%, and 3-D passing rates for PTVs and OARs were analyzed. Results: TPS dose distributions differed from those of film, especially for Head & neck. The dose difference between TPS and film results from calculation accuracy for complex motion of MLCs like tongue and groove effect. In contrast, MC dose distributions were in good agreement with those of film. This is because MC can model fully the MLC configuration and accurately reproduce the MLC motion between control points in VMAT plans. D95 of PTV for Prostate, Head & neck, C-shaped, and Multi Target was 97.2%, 98.1%, 101.6%, and 99.7% for TPS and 95.7%, 96.0%, 100.6%, and 99.1% for MC, respectively. Similarly, 3-D gamma passing rates of each PTV for TPS vs. MC were 100%, 89.5%, 99.7%, and 100%, respectively. 3-D passing rates of TPS reduced for complex VMAT fields like Head & neck because MLCs are not modeled completely for TPS. Conclusion: MC-calculated VMAT dose distributions is useful for the 3-D dose verification of VMAT plans by TPS.« less

Fractal spectral triples on Kellendonk's C∗-algebra of a substitution tiling

NASA Astrophysics Data System (ADS)

Mampusti, Michael; Whittaker, Michael F.

2017-02-01

We introduce a new class of noncommutative spectral triples on Kellendonk's C∗-algebra associated with a nonperiodic substitution tiling. These spectral triples are constructed from fractal trees on tilings, which define a geodesic distance between any two tiles in the tiling. Since fractals typically have infinite Euclidean length, the geodesic distance is defined using Perron-Frobenius theory, and is self-similar with scaling factor given by the Perron-Frobenius eigenvalue. We show that each spectral triple is θ-summable, and respects the hierarchy of the substitution system. To elucidate our results, we construct a fractal tree on the Penrose tiling, and explicitly show how it gives rise to a collection of spectral triples.

Electromagnetic absorption properties of spacecraft and space debris

NASA Astrophysics Data System (ADS)

Micheli, D.; Santoni, F.; Giusti, A.; Delfini, A.; Pastore, R.; Vricella, A.; Albano, M.; Arena, L.; Piergentili, F.; Marchetti, M.

2017-04-01

Aim of the work is to present a method to evaluate the electromagnetic absorption properties of spacecraft and space debris. For these objects, the radar detection ability depends mainly on volume, shape, materials type and other electromagnetic reflecting behaviour of spacecraft surface components, such as antennas or thermal blankets, and of metallic components in space debris. The higher the electromagnetic reflection coefficient of such parts, the greater the radar detection possibility. In this research an electromagnetic reverberation chamber is used to measure the absorption cross section (ACS) of four objects which may represent space structure operating components as well as examples of space debris: a small satellite, a composite antenna dish, a Thermal Protection System (TPS) tile and a carbon-based composite missile shell. The ACS mainly depends on geometrical characteristics like apertures, face numbers and bulk porosity, as well as on the type of the material itself. The ACS, which is an electromagnetic measurement, is expressed in squared meters and thus can be compared with the objects geometrical cross section. A small ACS means a quite electromagnetic reflective tendency, which is beneficial for radar observations; on the contrary, high values of ACS indicate a strong absorption of the electromagnetic field, which in turn can result a critical hindering of radar tracking.

KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, KSC employee Chris Moore repairs tile on the forward area of the orbiter Discovery. The vehicle has undergone Orbiter Major Modifications in the past year, which includes tile check and repair. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000° Fahrenheit, which are produced during descent for landing. Discovery is scheduled to fly on mission STS-121 to the International Space Station.

NASA Image and Video Library

2003-12-09

KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, KSC employee Chris Moore repairs tile on the forward area of the orbiter Discovery. The vehicle has undergone Orbiter Major Modifications in the past year, which includes tile check and repair. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000° Fahrenheit, which are produced during descent for landing. Discovery is scheduled to fly on mission STS-121 to the International Space Station.

Early Performance and Safety of the Micra Transcatheter Pacemaker in Pigs.

PubMed

Bonner, Matthew; Eggen, Michael; Haddad, Tarek; Sheldon, Todd; Williams, Eric

2015-11-01

The Micra® Transcatheter Pacing System (TPS; Medtronic Inc., Minneapolis, MN, USA) is a miniaturized single-chamber pacemaker system that is delivered via catheter through the femoral vein. In this study, the electrical performance was compared between the TPS and a traditional leaded pacemaker. In addition, the safety profile of the two systems was compared by thorough monitoring for a number of adverse events. The TPS was implanted in the right ventricular apex of 10 Yucatan mini pigs and a Medtronic single-lead pacemaker (SLP) was implanted in the right ventricular apex of another 10 pigs and connected to a traditional pacemaker. The electrical performance of all devices was monitored for 12 weeks. The safety profile of each system was characterized using x-ray, computed tomography, ultrasound, blood work, and necropsy to monitor for a variety of adverse events. At implant the mean pacing thresholds were 0.58 ± 0.17 V @0.24 ms and 0.75 ± 0.29 V @0.21 ms for the TPS and the SLP respectively. After 12 weeks, mean thresholds were 0.94 ± 0.46 V and 1.85 ± 0.75 V (P < 0.0001). There were two pulmonary emboli that were small and past the tertiary branch, and one occurred in each arm. There were also two infections with one in each arm. There were no dislodgements (macro or micro), tissue injury, tamponade, or valve injury. Overall, despite the 10-fold size reduction of the Micra TPS, it appears to perform similarly and have a similar safety profile to a traditional pacemaker system. © 2015 Medtronic PLC. Pacing and Clinical Electrophysiology published by Wiley Periodicals, Inc.

Use of an engineering data management system in the analysis of Space Shuttle Orbiter tiles

NASA Technical Reports Server (NTRS)

Giles, G. L.; Vallas, M.

1981-01-01

This paper demonstrates the use of an engineering data management system to facilitate the extensive stress analyses of the Space Shuttle Orbiter thermal protection system. Descriptions are given of the approach and methods used (1) to gather, organize, and store the data, (2) to query data interactively, (3) to generate graphic displays of the data, and (4) to access, transform, and prepare the data for input to a stress analysis program. The relational information management system was found to be well suited to the tile analysis problem because information related to many separate tiles could be accessed individually from a data base having a natural organization from an engineering viewpoint. The flexible user features of the system facilitated changes in data content and organization which occurred during the development and refinement of the tile analysis procedure. Additionally, the query language supported retrieval of data to satisfy a variety of user-specified conditions.

KSC-05pd2514

NASA Image and Video Library

2005-11-19

KENNEDY SPACE CENTER, FLA. - Inside the RLV Hangar at NASA Kennedy Space Center, employees move equipment being returned to the Thermal Protection System (TPS) facility. The upper floor, where soft material was processed, was damaged during the 2004 hurricanes. While the TPS facility was being repaired, normal work activity was done in the hangar.

ATLAS Tile calorimeter calibration and monitoring systems

NASA Astrophysics Data System (ADS)

Chomont, Arthur; ATLAS Collaboration

2017-11-01

The ATLAS Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes (PMTs), located on the outside of the calorimeter. The readout is segmented into about 5000 cells (longitudinally and transversally), each of them being read out by two PMTs in parallel. To calibrate and monitor the stability and performance of each part of the readout chain during the data taking, a set of calibration systems is used. The TileCal calibration system comprises cesium radioactive sources, Laser and charge injection elements, and allows for monitoring and equalization of the calorimeter response at each stage of the signal production, from scintillation light to digitization. Based on LHC Run 1 experience, several calibration systems were improved for Run 2. The lessons learned, the modifications, and the current LHC Run 2 performance are discussed.

Data acquisition and processing in the ATLAS tile calorimeter phase-II upgrade demonstrator

NASA Astrophysics Data System (ADS)

Valero, A.; Tile Calorimeter System, ATLAS

2017-10-01

The LHC has planned a series of upgrades culminating in the High Luminosity LHC which will have an average luminosity 5-7 times larger than the nominal Run 2 value. The ATLAS Tile Calorimeter will undergo an upgrade to accommodate the HL-LHC parameters. The TileCal readout electronics will be redesigned, introducing a new readout strategy. A Demonstrator program has been developed to evaluate the new proposed readout architecture and prototypes of all the components. In the Demonstrator, the detector data received in the Tile PreProcessors (PPr) are stored in pipeline buffers and upon the reception of an external trigger signal the data events are processed, packed and readout in parallel through the legacy ROD system, the new Front-End Link eXchange system and an ethernet connection for monitoring purposes. This contribution describes in detail the data processing and the hardware, firmware and software components of the TileCal Demonstrator readout system.

Application of Terahertz Radiation to the Detection of Corrosion Under the Shuttle's Thermal Protection System

NASA Astrophysics Data System (ADS)

Madaras, Eric I.; Anastasi, Robert F.; Smith, Stephen W.; Seebo, Jeffrey P.; Walker, James L.; Lomness, Janice K.; Hintze, Paul E.; Kammerer, Catherine C.; Winfree, William P.; Russell, Richard W.

2008-02-01

There is currently no method for detecting corrosion under Shuttle tiles except for the expensive process of tile removal and replacement; hence NASA is investigating new NDE methods for detecting hidden corrosion. Time domain terahertz radiation has been applied to corrosion detection under tiles in samples ranging from small lab samples to a Shuttle with positive results. Terahertz imaging methods have been able to detect corrosion at thicknesses of 5 mils or greater under 1" thick Shuttle tiles and 7-12 mils or greater under 2" thick Shuttle tiles.

NASA TileWorld manual (system version 2.2)

NASA Technical Reports Server (NTRS)

Philips, Andrew B.; Bresina, John L.

1991-01-01

The commands are documented of the NASA TileWorld simulator, as well as providing information about how to run it and extend it. The simulator, implemented in Common Lisp with Common Windows, encodes a particular range in a spectrum of domains, for controllable research experiments. TileWorld consists of a two dimensional grid of cells, a set of polygonal tiles, and a single agent which can grasp and move tiles. In addition to agent executable actions, there is an external event over which the agent has not control; this event correspond to a 'gust of wind'.

Application of Terahertz Radiation to the Detection of Corrosion under the Shuttle's Thermal Protection System

NASA Technical Reports Server (NTRS)

Madaras, Eric I.; Anastasi, Robert F.; Smith, Stephen W.; Seebo, Jeffrey P.; Walker, James L.; Lomness, Janice K.; Hintze, Paul E.; Kammerer, Catherine C.; Winfree, William P.; Russell, Richard W.

2007-01-01

There is currently no method for detecting corrosion under Shuttle tiles except for the expensive process of tile removal and replacement; hence NASA is investigating new NDE methods for detecting hidden corrosion. Time domain terahertz radiation has been applied to corrosion detection under tiles in samples ranging from small lab samples to a Shuttle with positive results. Terahertz imaging methods have been able to detect corrosion at thicknesses of 5 mils or greater under 1" thick Shuttle tiles and 7-12 mils or greater under 2" thick Shuttle tiles.

Nonlinear dynamic phenomena in the space shuttle thermal protection system

NASA Technical Reports Server (NTRS)

Housner, J. M.; Edighoffer, H. H.; Park, K. C.

1981-01-01

The development of an analysis for examining the nonlinear dynamic phenomena arising in the space shuttle orbiter tile/pad thermal protection system is presented. The tile/pad system consists of ceramic tiles bonded to the aluminum skin of the orbiter through a thin nylon felt pad. The pads are a soft nonlinear material which permits large strains and displays both hysteretic and nonlinear viscous damping. Application of the analysis to a square tile subjected to transverse sinusoidal motion of the orbiter skin is presented and the following nonlinear dynamic phenomena are considered: highly distorted wave forms, amplitude-dependent resonant frequencies which initially decrease and then increase with increasing amplitude of motion, magnification of substrate motion which is higher than would be expected in a similarly highly damped linear system, and classical parametric resonance instability.

Poster - Thur Eve - 68: Evaluation and analytical comparison of different 2D and 3D treatment planning systems using dosimetry in anthropomorphic phantom.

PubMed

Khosravi, H R; Nodehi, Mr Golrokh; Asnaashari, Kh; Mahdavi, S R; Shirazi, A R; Gholami, S

2012-07-01

The aim of this study was to evaluate and analytically compare different calculation algorithms applied in our country radiotherapy centers base on the methodology developed by IAEA for treatment planning systems (TPS) commissioning (IAEA TEC-DOC 1583). Thorax anthropomorphic phantom (002LFC CIRS inc.), was used to measure 7 tests that simulate the whole chain of external beam TPS. The dose were measured with ion chambers and the deviation between measured and TPS calculated dose was reported. This methodology, which employs the same phantom and the same setup test cases, was tested in 4 different hospitals which were using 5 different algorithms/ inhomogeneity correction methods implemented in different TPS. The algorithms in this study were divided into two groups including correction based and model based algorithms. A total of 84 clinical test case datasets for different energies and calculation algorithms were produced, which amounts of differences in inhomogeneity points with low density (lung) and high density (bone) was decreased meaningfully with advanced algorithms. The number of deviations outside agreement criteria was increased with the beam energy and decreased with advancement of the TPS calculation algorithm. Large deviations were seen in some correction based algorithms, so sophisticated algorithms, would be preferred in clinical practices, especially for calculation in inhomogeneous media. Use of model based algorithms with lateral transport calculation, is recommended. Some systematic errors which were revealed during this study, is showing necessity of performing periodic audits on TPS in radiotherapy centers. © 2012 American Association of Physicists in Medicine.

Thermal protection system gap analysis using a loosely coupled fluid-structural thermal numerical method

NASA Astrophysics Data System (ADS)

Huang, Jie; Li, Piao; Yao, Weixing

2018-05-01

A loosely coupled fluid-structural thermal numerical method is introduced for the thermal protection system (TPS) gap thermal control analysis in this paper. The aerodynamic heating and structural thermal are analyzed by computational fluid dynamics (CFD) and numerical heat transfer (NHT) methods respectively. An interpolation algorithm based on the control surface is adopted for the data exchanges on the coupled surface. In order to verify the analysis precision of the loosely coupled method, a circular tube example was analyzed, and the wall temperature agrees well with the test result. TPS gap thermal control performance was studied by the loosely coupled method successfully. The gap heat flux is mainly distributed in the small region at the top of the gap which is the high temperature region. Besides, TPS gap temperature and the power of the active cooling system (CCS) calculated by the traditional uncoupled method are higher than that calculated by the coupled method obviously. The reason is that the uncoupled method doesn't consider the coupled effect between the aerodynamic heating and structural thermal, however the coupled method considers it, so TPS gap thermal control performance can be analyzed more accurately by the coupled method.

Improved transition path sampling methods for simulation of rare events

NASA Astrophysics Data System (ADS)

Chopra, Manan; Malshe, Rohit; Reddy, Allam S.; de Pablo, J. J.

2008-04-01

The free energy surfaces of a wide variety of systems encountered in physics, chemistry, and biology are characterized by the existence of deep minima separated by numerous barriers. One of the central aims of recent research in computational chemistry and physics has been to determine how transitions occur between deep local minima on rugged free energy landscapes, and transition path sampling (TPS) Monte-Carlo methods have emerged as an effective means for numerical investigation of such transitions. Many of the shortcomings of TPS-like approaches generally stem from their high computational demands. Two new algorithms are presented in this work that improve the efficiency of TPS simulations. The first algorithm uses biased shooting moves to render the sampling of reactive trajectories more efficient. The second algorithm is shown to substantially improve the accuracy of the transition state ensemble by introducing a subset of local transition path simulations in the transition state. The system considered in this work consists of a two-dimensional rough energy surface that is representative of numerous systems encountered in applications. When taken together, these algorithms provide gains in efficiency of over two orders of magnitude when compared to traditional TPS simulations.

Geology and assessment of the undiscovered, technically recoverable petroleum resources of Armenia, 2013

USGS Publications Warehouse

Klett, T.R.

2016-02-23

The U.S. Geological Survey (USGS) assessed the undiscovered, technically recoverable oil and gas resources of Armenia in 2013. A Paleozoic and a Cenozoic total petroleum system (TPS) were identified within the country of Armenia. The postulated petroleum system elements are uncertain, resulting in low geologic probabilities for significant oil an gas resources. Two assessment units (AU) were delineated in each TPS—a Paleozoic-Sourced Conventional Reservoirs AU and a Permian Shale Gas AU in the Paleozoic Composite TPS and a Paleogene-Sourced Conventional Reservoirs AU and a Cenozoic Coalbed Gas AU in the Cenozoic Composite TPS. The TPS elements are largely uncertain and risked, and so only the Paleogene-Sourced Conventional Reservoirs AU was quantitatively assessed because the geologic probability is more than the threshold of 10 percent (that is, the probability of at least one conventional oil or gas accumulation of 5 million barrels of oil equivalent or greater based on postulated petroleum-system elements). The USGS estimated fully risked mean volumes of about 1 million barrels of oil (MMBO), about 6 billion cubic feet of natural gas (BCFG), and less than 1 million barrels of natural gas liquids (MMBNGL).

Monte Carlo-based QA for IMRT of head and neck cancers

NASA Astrophysics Data System (ADS)

Tang, F.; Sham, J.; Ma, C.-M.; Li, J.-S.

2007-06-01

It is well-known that the presence of large air cavity in a dense medium (or patient) introduces significant electronic disequilibrium when irradiated with megavoltage X-ray field. This condition may worsen by the possible use of tiny beamlets in intensity-modulated radiation therapy (IMRT). Commercial treatment planning systems (TPSs), in particular those based on the pencil-beam method, do not provide accurate dose computation for the lungs and other cavity-laden body sites such as the head and neck. In this paper we present the use of Monte Carlo (MC) technique for dose re-calculation of IMRT of head and neck cancers. In our clinic, a turn-key software system is set up for MC calculation and comparison with TPS-calculated treatment plans as part of the quality assurance (QA) programme for IMRT delivery. A set of 10 off-the-self PCs is employed as the MC calculation engine with treatment plan parameters imported from the TPS via a graphical user interface (GUI) which also provides a platform for launching remote MC simulation and subsequent dose comparison with the TPS. The TPS-segmented intensity maps are used as input for the simulation hence skipping the time-consuming simulation of the multi-leaf collimator (MLC). The primary objective of this approach is to assess the accuracy of the TPS calculations in the presence of air cavities in the head and neck whereas the accuracy of leaf segmentation is verified by fluence measurement using a fluoroscopic camera-based imaging device. This measurement can also validate the correct transfer of intensity maps to the record and verify system. Comparisons between TPS and MC calculations of 6 MV IMRT for typical head and neck treatments review regional consistency in dose distribution except at and around the sinuses where our pencil-beam-based TPS sometimes over-predicts the dose by up to 10%, depending on the size of the cavities. In addition, dose re-buildup of up to 4% is observed at the posterior nasopharyngeal mucosa for some treatments with heavily-weighted anterior fields.

Illinois drainage water management demonstration project

USGS Publications Warehouse

Pitts, D.J.; Cooke, R.; Terrio, P.J.; ,

2004-01-01

Due to naturally high water tables and flat topography, there are approximately 4 million ha (10 million ac) of farmland artificially drained with subsurface (tile) systems in Illinois. Subsurface drainage is practiced to insure trafficable field conditions for farm equipment and to reduce crop stress from excess water within the root zone. Although drainage is essential for economic crop production, there have been some significant environmental costs. Tile drainage systems tend to intercept nutrient (nitrate) rich soil-water and shunt it to surface water. Data from numerous monitoring studies have shown that a significant amount of the total nitrate load in Illinois is being delivered to surface water from tile drainage systems. In Illinois, these drainage systems are typically installed without control mechanisms and allow the soil to drain whenever the water table is above the elevation of the tile outlet. An assessment of water quality in the tile drained areas of Illinois showed that approximately 50 percent of the nitrate load was being delivered through the tile systems during the fallow period when there was no production need for drainage to occur. In 1998, a demonstration project to introduce drainage water management to producers in Illinois was initiated by NRCS4 An initial aspect of the project was to identify producers that were willing to manage their drainage system to create a raised water table during the fallow (November-March) period. Financial assistance from two federal programs was used to assist producers in retrofitting the existing drainage systems with control structures. Growers were also provided guidance on the management of the structures for both water quality and production benefits. Some of the retrofitted systems were monitored to determine the effect of the practice on water quality. This paper provides background on the water quality impacts of tile drainage in Illinois, the status of the demonstration project, preliminary monitoring results, and other observations.

Material characterization and modeling with shear ography

NASA Technical Reports Server (NTRS)

Workman, Gary L.; Callahan, Virginia

1993-01-01

Shearography has emerged as a useful technique for nondestructible evaluation and materials characterization of aerospace materials. A suitable candidate for the technique is to determine the response of debonds on foam-metal interfaces such as the TPS system on the External Tank. The main thrust is to develop a model which allows valid interpretation of shearographic information on TPS type systems. Confirmation of the model with shearographic data will be performed.

Comparative Study between Measurement Data and Treatment Planning System (TPS) in Small Fields for High Energy Photon Beams.

PubMed

El Shahat, Khaled; El Saeid, Aziza; Attalla, Ehab; Yassin, Adel

2014-01-01

To achieve tumor control for radiotherapy, a dose distribution is planned which has a good chance of sterilizing all cancer cells without causing unacceptable normal tissue complications. The aim of the present study was to achieve an accurate calculation of dose for small field dimensions and perform this by evaluating the accuracy of planning system calculation. This will be compared with real measurement of dose for the same small field dimensions using different detectors. Practical work was performed in two steps: (i) determination of the physical factors required for dose estimation measured by three ionization chambers and calculated by treatment planning system (TPS) based on the latest technical report series (IAEATRS-398) and (ii) comparison of the calculated and measured data. Our data analysis for small field is irradiated by photon energy matched with the data obtained from the ionization chambers and the treatment planning system. Radiographic films were used as an additional detector for the obtained data and showed matching with TPS calculation. It can be concluded that studied small field dimensions were averaged 6% and 4% for 6 MV and 15 MV, respectively. Radiographic film measurements showed a variation in results within ±2% than TPS calculation.

Understanding the Elementary Steps in DNA Tile-Based Self-Assembly.

PubMed

Jiang, Shuoxing; Hong, Fan; Hu, Huiyu; Yan, Hao; Liu, Yan

2017-09-26

Although many models have been developed to guide the design and implementation of DNA tile-based self-assembly systems with increasing complexity, the fundamental assumptions of the models have not been thoroughly tested. To expand the quantitative understanding of DNA tile-based self-assembly and to test the fundamental assumptions of self-assembly models, we investigated DNA tile attachment to preformed "multi-tile" arrays in real time and obtained the thermodynamic and kinetic parameters of single tile attachment in various sticky end association scenarios. With more sticky ends, tile attachment becomes more thermostable with an approximately linear decrease in the free energy change (more negative). The total binding free energy of sticky ends is partially compromised by a sequence-independent energy penalty when tile attachment forms a constrained configuration: "loop". The minimal loop is a 2 × 2 tetramer (Loop4). The energy penalty of loops of 4, 6, and 8 tiles was analyzed with the independent loop model assuming no interloop tension, which is generalizable to arbitrary tile configurations. More sticky ends also contribute to a faster on-rate under isothermal conditions when nucleation is the rate-limiting step. Incorrect sticky end contributes to neither the thermostability nor the kinetics. The thermodynamic and kinetic parameters of DNA tile attachment elucidated here will contribute to the future improvement and optimization of tile assembly modeling, precise control of experimental conditions, and structural design for error-free self-assembly.

CFD-Predicted Tile Heating Bump Factors Due to Tile Overlay Repairs

NASA Technical Reports Server (NTRS)

Lessard, Victor R.

2006-01-01

A Computational Fluid Dynamics investigation of the Orbiter's Tile Overlay Repair (TOR) is performed to assess the aeroheating Damage Assessment Team's (DAT) existing heating correlation method for protuberance interference heating on the surrounding thermal protection system. Aerothermodynamic heating analyses are performed for TORs at the design reference damage locations body points 1800 and 1075 for a Mach 17.9 and a=39deg STS-107 flight trajectory point with laminar flow. Six different cases are considered. The computed peak heating bump factor on the surrounding tiles are below the DAT's heating bump factor values for smooth tile cases. However, for the uneven tiles cases the peak interference heating is shown to be considerably higher than the existing correlation prediction.

Assessment of Appalachian Basin Oil and Gas Resources: Utica-Lower Paleozoic Total Petroleum System

USGS Publications Warehouse

Ryder, Robert T.

2008-01-01

The Utica-Lower Paleozoic Total Petroleum System (TPS) is an important TPS identified in the 2002 U.S. Geological Survey (USGS) assessment of undiscovered, technically recoverable oil and gas resources in the Appalachian basin province (Milici and others, 2003). The TPS is named for the Upper Ordovician Utica Shale, which is the primary source rock, and for multiple lower Paleozoic sandstone and carbonate units that are the important reservoirs. Upper Cambrian through Upper Silurian petroleum-bearing strata that constitute the Utica-Lower Paleozoic TPS thicken eastward from about 2,700 ft at the western margin of the Appalachian basin to about 12,000 ft at the thrust-faulted eastern margin of the Appalachian basin. The Utica-Lower Paleozoic TPS covers approximately 170,000 mi2 of the Appalachian basin from northeastern Tennessee to southeastern New York and from central Ohio to eastern West Virginia. The boundary of the TPS is defined by the following geologic features: (1) the northern boundary (from central Ontario to northeastern New York) extends along the outcrop limit of the Utica Shale-Trenton Limestone; (2) the northeastern boundary (from southeastern New York, through southeastern Pennsylvania-western Maryland-easternmost West Virginia, to northern Virginia) extends along the eastern limit of the Utica Shale-Trenton Limestone in the thrust-faulted eastern margin of the Appalachian basin; (3) the southeastern boundary (from west-central and southwestern Virginia to eastern Tennessee) extends along the eastern limit of the Trenton Limestone in the thrust-faulted eastern margin of the Appalachian basin; (4) the southwestern boundary (from eastern Tennessee, through eastern Kentucky, to southwestern Ohio) extends along the approximate facies change from the Trenton Limestone with thin black shale interbeds (on the east) to the equivalent Lexington Limestone without black shale interbeds (on the west); (5) the northern part of the boundary in southwestern Ohio to the Indiana border extends along an arbitrary boundary between the Utica Shale of the Appalachian basin and the Utica Shale of the Sebree trough (Kolata and others, 2001); and (6) the northwestern boundary (from east-central Indiana, through northwesternmost Ohio and southeasternmost Michigan, to central Ontario) extends along the approximate southeastern boundary of the Michigan Basin. Although the Utica-Lower Paleozoic TPS extends into northwestern Ohio, southeastern Michigan, and northeastern Indiana, these areas have been assigned to the Michigan Basin (Swezey and others, 2005) and are outside the scope of this report. Furthermore, although the northern part of the Utica-Lower Paleozoic TPS extends across the Great Lakes (Lake Erie and Lake Ontario) into southern Ontario, Canada, only the undiscovered oil and gas resources in the U.S. waters of the Great Lakes have been included in the USGS assessment of the Utica-Lower Paleozoic TPS. This TPS is similar to the Point Pleasant-Brassfield petroleum system previously identified by Drozd and Cole (1994) in the Ohio part of the Appalachian basin.

Overview of the Aerothermodynamics Analysis Conducted in Support of the STS-107 Accident Investigation

NASA Technical Reports Server (NTRS)

Campbell, Charles H.

2004-01-01

A graphic presentation of the aerothermodynamics analysis conducted in support of the STS-107 accident investigation. Investigation efforts were conducted as part of an integrated AATS team (Aero, Aerothermal, Thermal, Stress) directed by OVEWG. Graphics presented are: STS-107 Entry trajectory and timeline (1st off-nominal event to Post-LOS); Indications from OI telemetry data; Aero/aerothermo/thermal analysis process; Selected STS-107 side fuselage/OMS pod off-nominal temperatures; Leading edge structural subsystem; Relevant forensics evidence; External aerothermal environments; STS-107 Pre-entry EOM3 heating profile; Surface heating and temperatures; Orbiter wing leading edge damage survey; Internal aerothermal environments; Orbiter wing CAD model; Aerodynamic flight reconstruction; Chronology of aerodynamic/aerothermoydynamic contributions; Acreage TPS tile damage; Larger OML perturbations; Missing RCC panel(s); Localized damage to RCC panel/missing T-seal; RCC breach with flow ingestion; and Aero-aerothermal closure. NAIT served as the interface between the CAIB and NASA investigation teams; and CAIB requests for study were addressed.

Self assembly of rectangular shapes on concentration programming and probabilistic tile assembly models.

PubMed

Kundeti, Vamsi; Rajasekaran, Sanguthevar

2012-06-01

Efficient tile sets for self assembling rectilinear shapes is of critical importance in algorithmic self assembly. A lower bound on the tile complexity of any deterministic self assembly system for an n × n square is [Formula: see text] (inferred from the Kolmogrov complexity). Deterministic self assembly systems with an optimal tile complexity have been designed for squares and related shapes in the past. However designing [Formula: see text] unique tiles specific to a shape is still an intensive task in the laboratory. On the other hand copies of a tile can be made rapidly using PCR (polymerase chain reaction) experiments. This led to the study of self assembly on tile concentration programming models. We present two major results in this paper on the concentration programming model. First we show how to self assemble rectangles with a fixed aspect ratio ( α:β ), with high probability, using Θ( α + β ) tiles. This result is much stronger than the existing results by Kao et al. (Randomized self-assembly for approximate shapes, LNCS, vol 5125. Springer, Heidelberg, 2008) and Doty (Randomized self-assembly for exact shapes. In: proceedings of the 50th annual IEEE symposium on foundations of computer science (FOCS), IEEE, Atlanta. pp 85-94, 2009)-which can only self assembly squares and rely on tiles which perform binary arithmetic. On the other hand, our result is based on a technique called staircase sampling . This technique eliminates the need for sub-tiles which perform binary arithmetic, reduces the constant in the asymptotic bound, and eliminates the need for approximate frames (Kao et al. Randomized self-assembly for approximate shapes, LNCS, vol 5125. Springer, Heidelberg, 2008). Our second result applies staircase sampling on the equimolar concentration programming model (The tile complexity of linear assemblies. In: proceedings of the 36th international colloquium automata, languages and programming: Part I on ICALP '09, Springer-Verlag, pp 235-253, 2009), to self assemble rectangles (of fixed aspect ratio) with high probability. The tile complexity of our algorithm is Θ(log( n )) and is optimal on the probabilistic tile assembly model (PTAM)- n being an upper bound on the dimensions of a rectangle.

Simulating the Effects of Drainage and Agriculture on Hydrology and Sediment in the Minnesota River Basin

NASA Astrophysics Data System (ADS)

Downer, C. W.; Pradhan, N. R.; Skahill, B. E.; Banitt, A. M.; Eggers, G.; Pickett, R. E.

2014-12-01

Throughout the Midwest region of the United States, slopes are relatively flat, soils tend to have low permeability, and local water tables are high. In order to make the region suitable for agriculture, farmers have installed extensive networks of ditches to drain off excess surface water and subsurface tiles to lower the water table and remove excess soil water in the root zone that can stress common row crops, such as corn and soybeans. The combination of tiles, ditches, and intensive agricultural land practices radically alters the landscape and hydrology. Within the watershed, tiles have outlets to both the ditch/stream network as well as overland locations, where the tile discharge appears to initiate gullies and exacerbate overland erosion. As part of the Minnesota River Basin Integrated Study we are explicitly simulating the tile and drainage systems in the watershed at multiple scales using the physics-based watershed model GSSHA (Gridded Surface Subsurface Hydrologic Analysis). The tile drainage system is simulated as a network of pipes that collect water from the local water table. Within the watershed, testing of the methods on smaller basins shows the ability of the model to simulate tile flow, however, application at the larger scale is hampered by the computational burden of simulating the flow in the complex tile drain networks that drain the agricultural fields. Modeling indicates the subsurface drains account for approximately 40% of the stream flow in the Seven Mile Creek sub-basin account in the late spring and early summer when the tile is flowing. Preliminary results indicate that agricultural tile drains increase overland erosion in the Seven Mile Creek watershed.

Optimization of thermal protection systems for the space vehicle. Volume 2: User's manual

NASA Technical Reports Server (NTRS)

1972-01-01

The development of the computational techniques for the design optimization of thermal protection systems for the space shuttle vehicle are discussed. The resulting computer program was then used to perform initial optimization and sensitivity studies on a typical thermal protection system (TPS) to demonstrate its application to the space shuttle TPS design. The program was developed in FORTRAN IV for CDC 6400 computer, but it was subsequently converted to the FORTRAN V language to be used on the Univac 1108.

Pharmaceutical and personal care products in tile drainage following land application of municipal biosolids.

PubMed

Lapen, D R; Topp, E; Metcalfe, C D; Li, H; Edwards, M; Gottschall, N; Bolton, P; Curnoe, W; Payne, M; Beck, A

2008-07-25

Land application of municipal biosolids (sewage) is a common farming practice in many parts of the world. There is potential for transport of pharmaceuticals and personal care products (PPCPs) from agricultural fields to adjacent surface waters via tile drainage systems. In this study, liquid municipal biosolids (LMB) (total solids=11,933 mg L(-1)), supplemented with selected PPCPs and the fluorescent dye tracer rhodamine WT (RWT), were applied to tile drained fields using two land application approaches. Objectives included evaluating the relative benefits of land application practices with respect to reducing PPCP loadings to tile drains, evaluating PPCP persistence in tile water, and determining whether rhodamine WT can be used to estimate PPCP mass loads in tile. The PPCPs examined included an antibacterial agent used in personal care products (triclosan), a metabolite of nicotine (cotinine), and a variety of drugs including two sulfonamide antimicrobials (sulfapyridine, sulfamethoxazole), a beta-blocker (atenolol), an anti-epileptic (carbamazepine), an antidepressant (fluoxetine), analgesic/anti-inflammatories (acetaminophen, naproxen, ibuprofen), and a lipid-regulator (gemfibrozil). Maximum observed PPCP concentrations in the spiked LMB were about 10(3) ng g(-1) dry weight. PPCPs were shown to move rapidly via soil macropores to tile drains within minutes of the land application. Maximum observed PPCP concentrations in tile effluent associated with the LMB application-induced tile flow event were approximately 10(1) to 10(3) ng L(-1). PPCP mass loads, for the application-induced tile-hydrograph event, were significantly (p<0.1) higher for surface spreading over non-tilled soil (incorporation tillage occurring 20 h post-application), relative to aerating soil immediately prior to surface spreading using an AerWay slurry deposition system. PPCP concentrations that were detected above the limit of quantitation (LOQ) in tile water during several precipitation-induced tile flow events that occurred post-application, included: triclosan (max. approximately 1.5 x 10(2) ng L(-1)), carbamazepine (max. approximately 7 x 10(1) ng L(-1)), atenolol (max approximately 4 x 10(1) ng L(-1)), and cotinine (max approximately 2 x 10(1) ng L(-1)). In spite of their presence in biosolids, the other PPCPs were not observed above LOQ concentrations during these events. PPCP concentrations were predicted from RWT concentrations over a 40 day study period. Tile mass loads as a percent of PPCP mass applied to soil ranged from 4.2%+/-SD of 9.2% to 7.1%+/-10.9% for the AerWay system and surface spreading plus incorporation treatments, respectively.

A review of candidate multilayer insulation systems for potential use on wet-launched LH2 tankage for the space exploration initiative lunar missions

NASA Technical Reports Server (NTRS)

Knoll, Richard H.; Stochl, Robert J.; Sanabria, Rafael

1991-01-01

The storage of cryogenic propellants such as liquid hydrogen (LH2) and liquid oxygen (LO2) for the future Space Exploration Initiative (SEI) will require lightweight, high performance thermal protection systems (TPS's). For the near-term lunar missions, the major weight element for most of the TPS's will be multilayer insulation (MLI) and/or the special structures/systems required to accommodate the MLI. Methods of applying MLI to LH2 tankage to avoid condensation or freezing of condensible gases such as nitrogen or oxygen while in the atmosphere are discussed. Because relatively thick layers of MLI will be required for storage times of a month or more, the transient performance from ground-hold to space-hold of the systems will become important in optimizing the TPS's for many of the missions. The ground-hold performance of several candidate systems are given as well as a qualitative assessment of the transient performance effects.

Accounting for the risks of phosphorus losses through tile drains in a phosphorus index.

PubMed

Reid, D Keith; Ball, Bonnie; Zhang, T Q

2012-01-01

Tile drainage systems have been identified as a significant conduit for phosphorus (P) losses to surface water, but P indices do not currently account for this transport pathway in a meaningful way. Several P indices mention tile drains, but most account for either the reduction in surface runoff or the enhanced transport through tiles rather than both simultaneously. A summary of the current state of how tile drains are accounted for within P indices is provided, and the challenges in predicting the risk of P losses through tile drains that are relative to actual losses are discussed. A framework for a component P Index is described, along with a proposal to incorporate predictions of losses through tile drains as a component within this framework. Options for calibrating and testing this component are discussed. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Application programming in C# environment with recorded user software interactions and its application in autopilot of VMAT/IMRT treatment planning.

PubMed

Wang, Henry; Xing, Lei

2016-11-08

An autopilot scheme of volumetric-modulated arc therapy (VMAT)/intensity-modulated radiation therapy (IMRT) planning with the guidance of prior knowl-edge is established with recorded interactions between a planner and a commercial treatment planning system (TPS). Microsoft (MS) Visual Studio Coded UI is applied to record some common planner-TPS interactions as subroutines. The TPS used in this study is a Windows-based Eclipse system. The interactions of our application program with Eclipse TPS are realized through a series of subrou-tines obtained by prerecording the mouse clicks or keyboard strokes of a planner in operating the TPS. A strategy to autopilot Eclipse VMAT/IMRT plan selection process is developed as a specific example of the proposed "scripting" method. The autopiloted planning is navigated by a decision function constructed with a reference plan that has the same prescription and similar anatomy with the case at hand. The calculation proceeds by alternating between the Eclipse optimization and the outer-loop optimization independent of the Eclipse. In the C# program, the dosimetric characteristics of a reference treatment plan are used to assess and modify the Eclipse planning parameters and to guide the search for a clinically sensible treatment plan. The approach is applied to plan a head and neck (HN) VMAT case and a prostate IMRT case. Our study demonstrated the feasibility of application programming method in C# environment with recorded interactions of planner-TPS. The process mimics a planner's planning process and automatically provides clinically sensible treatment plans that would otherwise require a large amount of manual trial and error of a planner. The proposed technique enables us to harness a commercial TPS by application programming via the use of recorded human computer interactions and provides an effective tool to greatly facilitate the treatment planning process. © 2016 The Authors.

Application programming in C# environment with recorded user software interactions and its application in autopilot of VMAT/IMRT treatment planning

PubMed Central

Wang, Henry

2016-01-01

An autopilot scheme of volumetric‐modulated arc therapy (VMAT)/intensity‐modulated radiation therapy (IMRT) planning with the guidance of prior knowledge is established with recorded interactions between a planner and a commercial treatment planning system (TPS). Microsoft (MS) Visual Studio Coded UI is applied to record some common planner‐TPS interactions as subroutines. The TPS used in this study is a Windows‐based Eclipse system. The interactions of our application program with Eclipse TPS are realized through a series of subroutines obtained by prerecording the mouse clicks or keyboard strokes of a planner in operating the TPS. A strategy to autopilot Eclipse VMAT/IMRT plan selection process is developed as a specific example of the proposed “scripting” method. The autopiloted planning is navigated by a decision function constructed with a reference plan that has the same prescription and similar anatomy with the case at hand. The calculation proceeds by alternating between the Eclipse optimization and the outer‐loop optimization independent of the Eclipse. In the C# program, the dosimetric characteristics of a reference treatment plan are used to assess and modify the Eclipse planning parameters and to guide the search for a clinically sensible treatment plan. The approach is applied to plan a head and neck (HN) VMAT case and a prostate IMRT case. Our study demonstrated the feasibility of application programming method in C# environment with recorded interactions of planner‐TPS. The process mimics a planner's planning process and automatically provides clinically sensible treatment plans that would otherwise require a large amount of manual trial and error of a planner. The proposed technique enables us to harness a commercial TPS by application programming via the use of recorded human computer interactions and provides an effective tool to greatly facilitate the treatment planning process. PACS number(s): 87.55.D‐, 87.55.kd, 87.55.de PMID:27929493

NASA Research Center Contributions to Space Shuttle Return to Flight (SSRTF)

NASA Technical Reports Server (NTRS)

Cockrell, Charles E., Jr.; Barnes, Robert S.; Belvin, Harry L.; Allmen, John; Otero, Angel

2005-01-01

Contributions provided by the NASA Research Centers to key Space Shuttle return-to-flight milestones, with an emphasis on debris and Thermal Protection System (TPS) damage characterization, are described herein. Several CAIB recommendations and Space Shuttle Program directives deal with the mitigation of external tank foam insulation as a debris source, including material characterization as well as potential design changes, and an understanding of Orbiter TPS material characteristics, damage scenarios, and repair options. Ames, Glenn, and Langley Research Centers have performed analytic studies, conducted experimental testing, and developed new technologies, analysis tools, and hardware to contribute to each of these recommendations. For the External Tank (ET), these include studies of spray-on foam insulation (SOFI), investigations of potential design changes, and applications of advanced non-destructive evaluation (NDE) technologies to understand ET TPS shedding during liftoff and ascent. The end-to-end debris assessment included transport analysis to determine the probabilities of impact for various debris sources. For the Orbiter, methods were developed, and validated through experimental testing, to determine thresholds for potential damage of Orbiter TPS components. Analysis tools were developed and validated for on-orbit TPS damage assessments, especially in the area of aerothermal environments. Advanced NDE technologies were also applied to the Orbiter TPS components, including sensor technologies to detect wing leading edge impacts during liftoff and ascent. Work is continuing to develop certified TPS repair options and to develop improved methodologies for reinforced carbon-carbon (RCC) damage progression to assist in on-orbit repair decision philosophy.

Assessing the environmental fate of S-metolachlor, its commercial product Mercantor Gold® and their photoproducts using a water-sediment test and in silico methods.

PubMed

Gutowski, Lukasz; Baginska, Ewelina; Olsson, Oliver; Leder, Christoph; Kümmerer, Klaus

2015-11-01

Pesticides enter surface and groundwater by several routes in which partition to sediment contributes to their fate by abiotic (e.g. photolysis, hydrolysis) and biotic processes. Yet, little is known about S-metolachlor (SM) transformation in water-sediment systems. Therefore, a newly developed screening water-sediment test (WST) was applied to compare biodegradation and sorption processes between pure SM and Mercantor Gold® (MG), a commercial formulation of SM. Photolysis in water was performed by Xe lamp irradiation. Subsequently, the biodegradability of SM and MG photolysis mixtures was examined in WST. The primary elimination of SM from water phase was monitored and structures of its TPs resulting from biotransformation (bio-TPs) were elucidated by LC-MS/MS. SM was extracted from sediment in order to estimate the role of sorption in WST for its elimination. A set of in silico prediction software tools was applied for toxicity assessment of SM and its bio-TPs. Obtained results suggest that the MG adjuvants do not significantly affect biodegradation, but do influence diffusion of SM into sediment. 50% of SM could not be re-extracted from sediment with 0.01 M CaCl2 aqueous solution recommended in OECD test guideline for adsorption. Neither the parent compound nor the photo-TPs were biodegraded. However, new bio-TPs have been generated from SM and MG photo-TPs due to bacterial activity in the water-sediment interphase. Moreover, according to in silico assessment of the bio-TPs the biotransformation might lead to an increased toxicity to the water organisms compared with the SM. This might raise concerns of bio-TPs presence in the environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

SU-F-T-220: Validation of Hounsfield Unit-To-Stopping Power Ratio Calibration Used for Dose Calculation in Proton Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Polf, J; Chung, H; Langen, K

Purpose: To validate the stoichiometric calibration of the Hounsfield Unit (HU) to Stopping Power Ratio (SPR) calibration used to commission a commercial treatment planning system (TPS) for proton radiotherapy dose calculation. Methods and Materials: The water equivalent thickness (WET) of several individual pig tissues (lung, fat, muscle, liver, intestine, rib, femur), mixed tissue samples (muscle/rib, ice/femur, rib/air cavity/muscle), and an intact pig head were measured with a multi-layer ionization chamber (MLIC). A CT scan of each sample was obtained and imported into a commercial TPS. The WET calculated by the TPS for each tissue sample was compared to the measuredmore » WET value to determine the accuracy of the HU-to-SPR calibration curve used by the TPS to calculate dose. Results: The WET values calculated by the TPS showed good agreement (< 2.0%) with the measured values for bone and all soft tissues except fat (3.1% difference). For the mixed tissue samples and the intact pig head measurements, the difference in the TPS and measured WET values all agreed to within 3.5%. In addition, SPR values were calculated from the measured WET of each tissue, and compared to SPR values of reference tissues from ICRU 46 used to generate the HU-to-SPR calibration for the TPS. Conclusion: For clinical scenarios where the beam passes through multiple tissue types and its path is dominated by soft tissues, we believe using an uncertainty of 3.5% of the planned beam range is acceptable to account for uncertainties in the TPS WET determination.« less

STS-335 crew training, EVA TPS Overview with instructor John Ray

NASA Image and Video Library

2010-11-03

JSC2010-E-183513 (3 Nov. 2010) --- STS-135 crew members participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center. Pictured from the left are NASA astronauts Chris Ferguson, commander; Rex Walheim, mission specialist; Doug Hurley, pilot; and Sandy Magnus, mission specialist. John Ray (right) assisted the crew members. STS-135 is planned to be the final mission of the space shuttle program. Photo credit: NASA or National Aeronautics and Space Administration

STS-335 crew training, EVA TPS Overview with instructor John Ray

NASA Image and Video Library

2010-11-03

JSC2010-E-183514 (3 Nov. 2010) --- STS-135 crew members participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center. Pictured from the left are NASA astronauts Chris Ferguson, commander; Rex Walheim, mission specialist; Doug Hurley, pilot; and Sandy Magnus, mission specialist. John Ray (right) assisted the crew members. STS-135 is planned to be the final mission of the space shuttle program. Photo credit: NASA or National Aeronautics and Space Administration

STS-335 crew training, EVA TPS Overview with instructor John Ray

NASA Image and Video Library

2010-11-03

JSC2010-E-183512 (3 Nov. 2010) --- STS-135 crew members participate in an EVA Thermal Protection System (TPS) overview training session in the TPS/ Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center. Pictured from the left are NASA astronauts Chris Ferguson, commander; Rex Walheim, mission specialist; Doug Hurley, pilot; and Sandy Magnus, mission specialist. John Ray (right) assisted the crew members. STS-135 is planned to be the final mission of the space shuttle program. Photo credit: NASA or National Aeronautics and Space Administration

Integrated Solar-Energy-Harvesting and -Storage Device

NASA Technical Reports Server (NTRS)

whitacre, Jay; Fleurial, Jean-Pierre; Mojarradi, Mohammed; Johnson, Travis; Ryan, Margaret Amy; Bugga, Ratnakumar; West, William; Surampudi, Subbarao; Blosiu, Julian

2004-01-01

A modular, integrated, completely solid-state system designed to harvest and store solar energy is under development. Called the power tile, the hybrid device consists of a photovoltaic cell, a battery, a thermoelectric device, and a charge-control circuit that are heterogeneously integrated to maximize specific energy capacity and efficiency. Power tiles could be used in a variety of space and terrestrial environments and would be designed to function with maximum efficiency in the presence of anticipated temperatures, temperature gradients, and cycles of sunlight and shadow. Because they are modular in nature, one could use a single power tile or could construct an array of as many tiles as needed. If multiple tiles are used in an array, the distributed and redundant nature of the charge control and distribution hardware provides an extremely fault-tolerant system. The figure presents a schematic view of the device.

Thermo Physics Facilities Branch Brochure ARC Jet Complex Fact Sheets, Hypervelocity Free-Flight Aerodynamic Facility Fact Sheets, Ames Vertical Gun Range Fact Sheets

NASA Technical Reports Server (NTRS)

Fretter, E. F. (Editor); Kuhns, Jay (Editor); Nuez, Jay (Editor)

2003-01-01

The Ames Arc Jet Complex has a rich heritage of over 40 years in Thermal Protection System (TPS) development for every NASA Space Transportation and Planetary program, including Apollo, Space Shuttle, Viking, Pioneer-Venus, Galileo, Mars Pathfinder,Stardust, NASP,X-33,X-34,SHARP-B1 and B2,X-37 and Mars Exploration Rovers. With this early TPS history came a long heritage in the development of the arc jet facilities. These are used to simulate the aerodynamic heating that occurs on the nose cap, wing leading edges and on other areas of the spacecraft requiring thermal protection. TPS samples have been run in the arc jets from a few minutes to over an hour,from one exposure to multiple exposures of the same sample, in order t o understand the TPS materials response to a hot gas flow environment (representative of real hyperthermal environments experienced in flight). The Ames Arc l e t Complex is a key enabler for customers involved in the three major areas of TPS development: selection, validation, and qualification. The arc jet data are critical for validating TPS thermal models, heat shield designs and repairs, and ultimately for flight qualification.

Extraction, characterization and antioxidant activities of Se-enriched tea polysaccharides.

PubMed

Wang, Yuanfeng; Li, Yongfu; Liu, Yangyang; Chen, Xueqing; Wei, Xinlin

2015-01-01

Se-polysaccharides from Se-enriched tea leaves were purified by DEAE-sepharose fast flow gel column (2.5×60cm) and three polysaccharide fractions (Se-TPS1, Se-TPS2, and Se-TPS3) were isolated and purified with yields of 6.5, 37.14, and 8.57%, respectively. The average sizes of Se-TPS1 and Se-TPS2 were determined by HPGPC system, with molecular weights of 1.1×10(5) and 2.4×10(5)Da, respectively. Se-TPS3 was a polysaccharide polymer with two peaks with molecular weights of 9.2×10(5) and 2.5×10(5)Da. Monosaccharide components analysis by ion chromatography revealed Se-polysaccharides were acidic polysaccharoses and different from each other in monosaccharide kinds and molar ratio. Elements of Se, C, H, N, S, and 14 kinds of mineral elements were analyzed by AFS, EA, and ICP-AES, respectively. Spectral analysis (IR and UV) indicated Se-polysaccharides were typical glycoproteins. Morphological analyses of the samples were determined by SEM and AFM. In addition, the DPPH and superoxide radicals scavenging activities were also discussed to assess antioxidant activities of the samples, and Se-polysaccharides showed higher antioxidant activities compared to the ordinary polysaccharides. Copyright © 2015 Elsevier B.V. All rights reserved.

The organ-specific expression of terpene synthase genes contributes to the terpene hydrocarbon composition of chamomile essential oils.

PubMed

Irmisch, Sandra; Krause, Sandra T; Kunert, Grit; Gershenzon, Jonathan; Degenhardt, Jörg; Köllner, Tobias G

2012-06-08

The essential oil of chamomile, one of the oldest and agronomically most important medicinal plant species in Europe, has significant antiphlogistic, spasmolytic and antimicrobial activities. It is rich in chamazulene, a pharmaceutically active compound spontaneously formed during steam distillation from the sesquiterpene lactone matricine. Chamomile oil also contains sesquiterpene alcohols and hydrocarbons which are produced by the action of terpene synthases (TPS), the key enzymes in constructing terpene carbon skeletons. Here, we present the identification and characterization of five TPS enzymes contributing to terpene biosynthesis in chamomile (Matricaria recutita). Four of these enzymes were exclusively expressed in above-ground organs and produced the common terpene hydrocarbons (-)-(E)-β-caryophyllene (MrTPS1), (+)-germacrene A (MrTPS3), (E)-β-ocimene (MrTPS4) and (-)-germacrene D (MrTPS5). A fifth TPS, the multiproduct enzyme MrTPS2, was mainly expressed in roots and formed several Asteraceae-specific tricyclic sesquiterpenes with (-)-α-isocomene being the major product. The TPS transcript accumulation patterns in different organs of chamomile were consistent with the abundance of the corresponding TPS products isolated from these organs suggesting that the spatial regulation of TPS gene expression qualitatively contribute to terpene composition. The terpene synthases characterized in this study are involved in the organ-specific formation of essential oils in chamomile. While the products of MrTPS1, MrTPS2, MrTPS4 and MrTPS5 accumulate in the oils without further chemical alterations, (+)-germacrene A produced by MrTPS3 accumulates only in trace amounts, indicating that it is converted into another compound like matricine. Thus, MrTPS3, but also the other TPS genes, are good markers for further breeding of chamomile cultivars rich in pharmaceutically active essential oils.

Panel-flutter analysis of a thermal protection-shield concept for the space shuttle.

NASA Technical Reports Server (NTRS)

Cunningham, H. J.

1972-01-01

Analysis of the panel flutter characteristics of a candidate thermal protection system (TPS) for the space shuttle, using piston theory aerodynamics and Lagrange equations. The results show the TPS candidate panel array to be deep in the 'no-flutter' region during launch and, therefore, safe from panel flutter.

KSC-05pd2511

NASA Image and Video Library

2005-11-19

KENNEDY SPACE CENTER, FLA. - Employees at NASA Kennedy Space Center are transferring equipment stored in the RLV Hangar back to the Thermal Protection System (TPS) facility. The upper floor of the facility, where soft material was processed, was damaged during the 2004 hurricanes. While the TPS facility was being repaired, normal work activity was done in the hangar.

STS-135 crew during Ingress/Egress Timeline training in building 9NW space station mockups

NASA Image and Video Library

2011-04-29

JSC2011-E-043875 (29 April 2011) --- NASA astronaut Rex Walheim, STS-135 mission specialist, participates in an EVA Thermal Protection System (TPS) overview training session in the TPS/Precision Air Bearing Facility in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center. Photo credit: NASA

Calibration and performance of the ATLAS Tile Calorimeter during the LHC Run 2

NASA Astrophysics Data System (ADS)

Cerda Alberich, L.

2018-02-01

The Tile Calorimeter (TileCal) is the hadronic sampling calorimeter of the ATLAS experiment at the Large Hadron Collider (LHC). TileCal uses iron absorbers and scintillators as active material and it covers the central region | η| < 1.7. Jointly with the other sub-detectors it is designed for measurements of hadrons, jets, tau-particles and missing transverse energy. It also assists in muon identification. TileCal is regularly monitored and calibrated by several different calibration systems: a Cs radioactive source, a laser light system to check the PMT response, and a charge injection system (CIS) to check the front-end electronics. These calibration systems, in conjunction with data collected during proton-proton collisions, Minimum Bias (MB) events, provide extensive monitoring of the instrument and a means for equalizing the calorimeter response at each stage of the signal propagation. The performance of the calorimeter has been established with cosmic ray muons and the large sample of the proton-proton collisions and compared to Monte Carlo (MC) simulations. The response of high momentum isolated muons is also used to study the energy response at the electromagnetic scale, isolated hadrons are used as a probe of the hadronic response. The calorimeter time resolution is studied with multijet events. A description of the different TileCal calibration systems and the results on the calorimeter performance during the LHC Run 2 are presented. The results on the pile-up noise and response uniformity studies are also discussed.

TPS design for aerobraking at Earth and Mars

NASA Astrophysics Data System (ADS)

Williams, S. D.; Gietzel, M. M.; Rochelle, W. C.; Curry, D. M.

1991-08-01

An investigation was made to determine the feasibility of using an aerobrake system for manned and unmanned missions to Mars, and to Earth from Mars and lunar orbits. A preliminary thermal protection system (TPS) was examined for five unmanned small nose radius, straight bi-conic vehicles and a scaled up Aeroassist Flight Experiment (AFE) vehicle aerocapturing at Mars. Analyses were also conducted for the scaled up AFE and an unmanned Sample Return Cannister (SRC) returning from Mars and aerocapturing into Earth orbit. Also analyzed were three different classes of lunar transfer vehicles (LTV's): an expendable scaled up modified Apollo Command Module (CM), a raked cone (modified AFT), and three large nose radius domed cylinders. The LTV's would be used to transport personnel and supplies between Earth and the moon in order to establish a manned base on the lunar surface. The TPS for all vehicles analyzed is shown to have an advantage over an all-propulsive velocity reduction for orbit insertion. Results indicate that TPS weight penalties of less than 28 percent can be achieved using current material technology, and slightly less than the most favorable LTV using advanced material technology.

Development of Advanced Conformal Ablative TPS Fabricated from Rayon- and PAN-Based Carbon Felts

NASA Technical Reports Server (NTRS)

Gasch, Matthew; Stackpoole, Margaret; White, Susan; Boghozian, Tane

2016-01-01

The conformal ablative TPS first developed under NASA's Hypersonics Project in the early 2000's demonstrated very low through the thickness conductivity compared to state-ofthe- art PICA. However, in initial arcjet testing of Conformal-1, surface recession rates were 2x higher than PICA. Because commercial carbon felts are currently available as very thin substrates, this was a concern if conformal TPS were to be considered for a mission that required thicker material. Discussed in this paper are the results of the development of an Advanced Conformal TPS derived from thicker, higher density carbon felt. Two substrate systems were evaluated, the first material was a needled rayon-based carbon felt and the other a needled PAN-based carbon felt. Both substrates were impregnated with phenolic resin following the PICA/CPICA process to add a low density phenolic matrix to the system prior to aerothermal screening at the LaRC HyMETS facility and larger scale testing in the NASA ARC Interaction Heating Facility (IHF) at heating fluxes ranging from 250-1700 W/cm2.

Use of biochar amendments for removing bacteria from simulated tile-drainage waters

USDA-ARS?s Scientific Manuscript database

The addition of biochar has been shown to increase bacterial removal rates by several orders of magnitude in sand-packed columns, suggesting that biochar may be a suitable amendment for use in end-of-tile filter systems to remove indicator and pathogenic microorganisms in tile-drainage waters. Addit...

The ATLAS tile calorimeter performance at the LHC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calkins, R.

The Tile Calorimeter (TileCal), the central section of the hadronic calorimeter of the ATLAS experiment, is a key detector component to detect hadrons, jets and taus and to measure the missing transverse energy. Due to the very good muon signal to noise ratio it assists the spectrometer in the identification and reconstruction of muons. TileCal is built of steel and scintillating tiles coupled to optical fibers and read out by photomultipliers. The calorimeter is equipped with systems that allow to monitor and to calibrate each stage of the read out system exploiting different signal sources: laser light, charge injection andmore » a radioactive source. The performance of the calorimeter has been measured and monitored using calibration data, random triggered data, cosmic muons and more importantly LHC collision events. The results presented here assess the absolute energy scale calibration precision, the energy and timing uniformity and the synchronization precision. The ensemble of the results demonstrates a very good understanding of the performance of the Tile Calorimeter that is proved to be well within the design expectations. (authors)« less

A Finite-Rate Gas-Surface Interaction Model Informed by Fundamental Computational Chemistry Simulations

DTIC Science & Technology

2013-03-31

found to not thermally accommodate to the surface, rather they leave in excited vibrational levels. The new finite-rate model and thermal accommodation...vehicle’s thermal protection system (TPS). Many TPS materials act as a catalyst for the heterogeneous recombination of dissociated species back into...it is a significant component in both reusable (LI900, LI2200, FRSI) and ablative (SIRCA) thermal protection systems [24]. In addition, studies have

Assessment of undiscovered hydrocarbon resources of sub-Saharan Africa

USGS Publications Warehouse

Brownfield, Michael E.

2016-01-01

The assessment was geology-based and used the total petroleum system (TPS) concept. The geologic elements of a TPS are hydrocarbon source rocks (source rock maturation and hydrocarbon generation and migration), reservoir rocks (quality and distribution), and traps where hydrocarbon accumulates. Using these geologic criteria, 16 conventional total petroleum systems and 18 assessment units in the 13 provinces were defined. The undiscovered, technically recoverable oil and gas resources were assessed for all assessment units.

Study of Uncertainties of Predicting Space Shuttle Thermal Environment. [impact of heating rate prediction errors on weight of thermal protection system

NASA Technical Reports Server (NTRS)

Fehrman, A. L.; Masek, R. V.

1972-01-01

Quantitative estimates of the uncertainty in predicting aerodynamic heating rates for a fully reusable space shuttle system are developed and the impact of these uncertainties on Thermal Protection System (TPS) weight are discussed. The study approach consisted of statistical evaluations of the scatter of heating data on shuttle configurations about state-of-the-art heating prediction methods to define the uncertainty in these heating predictions. The uncertainties were then applied as heating rate increments to the nominal predicted heating rate to define the uncertainty in TPS weight. Separate evaluations were made for the booster and orbiter, for trajectories which included boost through reentry and touchdown. For purposes of analysis, the vehicle configuration is divided into areas in which a given prediction method is expected to apply, and separate uncertainty factors and corresponding uncertainty in TPS weight derived for each area.

Development and flight qualification of the C-SiC thermal protection systems for the IXV

NASA Astrophysics Data System (ADS)

Buffenoir, François; Zeppa, Céline; Pichon, Thierry; Girard, Florent

2016-07-01

The Intermediate experimental Vehicle (IXV) atmospheric re-entry demonstrator, developed within the FLPP (Future Launcher Preparatory Programme) and funded by ESA, aimed at developing a demonstration vehicle that gave Europe a unique opportunity to increase its knowledge in the field of advanced atmospheric re-entry technologies. A key technology that has been demonstrated in real conditions through the flight of this ambitious vehicle is the thermal protection system (TPS) of the Vehicle. Within this programme, HERAKLES, Safran Group, has been in charge of the TPS of the windward and nose assemblies of the vehicle, and has developed and manufactured SepcarbInox® ceramic matrix composite (CMC) protection systems that provided a high temperature resistant non ablative outer mould line (OML) for enhanced aerodynamic control. The design and flight justification of these TPS has been achieved through extensive analysis and testing:

Ablation Modeling of Ares-I Upper State Thermal Protection System Using Thermal Desktop

NASA Technical Reports Server (NTRS)

Sharp, John R.; Page, Arthur T.

2007-01-01

The thermal protection system (TPS) for the Ares-I Upper Stage will be based on Space Transportation System External Tank (ET) and Solid Rocket Booster (SRB) heritage materials. These TPS materials were qualified via hot gas testing that simulated ascent and re-entry aerothermodynamic convective heating environments. From this data, the recession rates due to ablation were characterized and used in thermal modeling for sizing the thickness required to maintain structural substrate temperatures. At Marshall Space Flight Center (MSFC), the in-house code ABL is currently used to predict TPS ablation and substrate temperatures as a FORTRAN application integrated within SINDA/G. This paper describes a comparison of the new ablation utility in Thermal Desktop and SINDA/FLUINT with the heritage ABL code and empirical test data which serves as the validation of the Thermal Desktop software for use on the design of the Ares-I Upper Stage project.

Assessment of a three‐dimensional (3D) water scanning system for beam commissioning and measurements on a helical tomotherapy unit

PubMed Central

Ashenafi, Michael S.; McDonald, Daniel G.; Vanek, Kenneth N.

2015-01-01

Beam scanning data collected on the tomotherapy linear accelerator using the TomoScanner water scanning system is primarily used to verify the golden beam profiles included in all Helical TomoTherapy treatment planning systems (TOMO TPSs). The user is not allowed to modify the beam profiles/parameters for beam modeling within the TOMO TPSs. The authors report the first feasibility study using the Blue Phantom Helix (BPH) as an alternative to the TomoScanner (TS) system. This work establishes a benchmark dataset using BPH for target commissioning and quality assurance (QA), and quantifies systematic uncertainties between TS and BPH. Reproducibility of scanning with BPH was tested by three experienced physicists taking five sets of measurements over a six‐month period. BPH provides several enhancements over TS, including a 3D scanning arm, which is able to acquire necessary beam‐data with one tank setup, a universal chamber mount, and the OmniPro software, which allows online data collection and analysis. Discrepancies between BPH and TS were estimated by acquiring datasets with each tank. In addition, data measured with BPH and TS was compared to the golden TOMO TPS beam data. The total systematic uncertainty, defined as the combination of scanning system and beam modeling uncertainties, was determined through numerical analysis and tabulated. OmniPro was used for all analysis to eliminate uncertainty due to different data processing algorithms. The setup reproducibility of BPH remained within 0.5 mm/0.5%. Comparing BPH, TS, and Golden TPS for PDDs beyond maximum depth, the total systematic uncertainties were within 1.4 mm/2.1%. Between BPH and TPS golden data, maximum differences in the field width and penumbra of in‐plane profiles were within 0.8 and 1.1 mm, respectively. Furthermore, in cross‐plane profiles, the field width differences increased at depth greater than 10 cm up to 2.5 mm, and maximum penumbra uncertainties were 5.6 mm and 4.6 mm from TS scanning system and TPS modeling, respectively. Use of BPH reduced measurement time by 1–2 hrs per session. The BPH has been assessed as an efficient, reproducible, and accurate scanning system capable of providing a reliable benchmark beam data. With this data, a physicist can utilize the BPH in a clinical setting with an understanding of the scan discrepancy that may be encountered while validating the TPS or during routine machine QA. Without the flexibility of modifying the TPS and without a golden beam dataset from the vendor or a TPS model generated from data collected with the BPH, this represents the best solution for current clinical use of the BPH. PACS number: 87.56.Fc

Expression Profiles of the Trehalose-6-Phosphate Synthase Gene Associated With Thermal Stress in Ostrinia furnacalis (Lepidoptera: Crambidae)

PubMed Central

Jin, Tingting; Gao, Yulin; He, Kanglai

2018-01-01

Abstract Trehalose is the major blood sugar in insects. Physiological significance of this compound has been extensively reported. Trehalose-6-phosphate synthase (TPS) is an important enzyme in the trehalose biosynthesis pathway. Full-length cDNAs of TPS (Of tps) and its alternative splicing isoform (Of tps_isoformI) were cloned from the Asian corn borer (ACB), Ostrinia furnacalis (Guenée; Lepidoptera: Crambidae) larvae. The Of tps and Of tps_isoformI transcripts were 2913 and 1689 bp long, contained 2529 and 1293 bp open reading frames encoding proteins of 842 and 430 amino acids with a molecular mass of 94.4 and 48.6 kDa, respectively. Transcriptional profiling and response to thermal stress of Of tps gene were determined by quantitative real-time PCR showing that the Of tps was predominantly expressed in the larval fat body, significantly enhanced during molting and transformation; and thermal stress also induced Of tps expression. Gene structure analysis is indicating that one TPS domain and one trehalose-6-phosphate phosphatase (TPP) domain were located at the N- and C-termini of Of        TPS, respectively, while only the TPS domain was detected in OfTPS_isoformI. Three-dimensional modeling and heterologous expression were developed to predict the putative functions of OfTPS and Of   TPS_isoformI. We infer that the expression of Of tps gene is thermally induced and might be crucial for larvae survival.

Hypersonic Materials and Structures

NASA Technical Reports Server (NTRS)

Glass, David E.

2016-01-01

Thermal protection systems (TPS) and hot structures are required for a range of hypersonic vehicles ranging from ballistic reentry to hypersonic cruise vehicles, both within Earth's atmosphere and non-Earth atmospheres. The focus of this presentation is on air breathing hypersonic vehicles in the Earth's atmosphere. This includes single-stage to orbit (SSTO), two-stage to orbit (TSTO) accelerators, access to space vehicles, and hypersonic cruise vehicles. This paper will start out with a brief discussion of aerodynamic heating and thermal management techniques to address the high heating, followed by an overview of TPS for rocket-launched and air-breathing vehicles. The argument is presented that as we move from rocket-based vehicles to air-breathing vehicles, we need to move away from the insulated airplane approach used on the Space Shuttle Orbiter to a wide range of TPS and hot structure approaches. The primary portion of the paper will discuss issues and design options for CMC TPS and hot structure components, including leading edges, acreage TPS, and control surfaces. The current state-of-the-art will be briefly discussed for some of the components.

Measuring the spectral emissivity of thermal protection materials during atmospheric reentry simulation

NASA Technical Reports Server (NTRS)

Marble, Elizabeth

1996-01-01

Hypersonic spacecraft reentering the earth's atmosphere encounter extreme heat due to atmospheric friction. Thermal Protection System (TPS) materials shield the craft from this searing heat, which can reach temperatures of 2900 F. Various thermophysical and optical properties of TPS materials are tested at the Johnson Space Center Atmospheric Reentry Materials and Structures Evaluation Facility, which has the capability to simulate critical environmental conditions associated with entry into the earth's atmosphere. Emissivity is an optical property that determines how well a material will reradiate incident heat back into the atmosphere upon reentry, thus protecting the spacecraft from the intense frictional heat. This report describes a method of measuring TPS emissivities using the SR5000 Scanning Spectroradiometer, and includes system characteristics, sample data, and operational procedures developed for arc-jet applications.

Overview of the Orion Thermal Protection System

NASA Technical Reports Server (NTRS)

Kowal, T. John

2010-01-01

The Orion spacecraft is being developed as part of the Constellation Exploration Program and will serve as the United States crewed transportation system to the International Space Station after the retirement of the Space Shuttle in 2010 and as the eventual means to return U.S. astronauts to the Moon. Therefore, Orion is being designed for reentry missions from both low Earth orbit and from Lunar-return trajectories. This presentation will provide an overview of the development of the Orion TPS, a critical component in the development of the spacecraft. The thermal protection system (TPS) that protects the crew module from the extreme environments associated with Earth atmospheric reentry consists of a forward heatshield and an aft backshell. The requirements that drive the design of the TPS will be discussed, including several key requirements that establish a precedent for U.S. human-rated spacecraft. For the first time in U.S. human spaceflight, a vehicle s TPS is being designed with a specific, derived requirement for reliability. Also, due to the increased presence of spacecraft in Earth s orbit in recent decades, requirements for micro-meteoroid/orbital debris damage tolerance are also a driving requirement that has affected the selection of portions of the TPS. The efforts to select materials and to define a preliminary design for both the heatshield and the backshell will be described. This will include a discussion of the design challenges presented by the numerous penetrations on both the backshell and the heatshield. Finally, the verification and validation plan which is currently under development to certify the TPS for human-rated missions will be outlined. To support the execution of this plan, a ground test campaign for both thermal and structural performance is being designed. This test campaign will directly support thermal and thermal/structural analyses that also are fundamental to the certification effort.

Assessment of the Mesaverde Total Petroleum System in Southwestern Wyoming Province: a petroleum system approach to assessing undiscovered oil and gas resources

USGS Publications Warehouse

Johnson, Ronald C.; Finn, Thomas M.

2003-01-01

The U.S. Geological Survey, in a recent assessment of the undiscovered oil and gas resources in the Southwestern Wyoming Province using a Total Petroleum System (TPS) approach, estimated a mean of 84.6 trillion cubic feet of gas (TCFG), 131 million barrels of oil (MMBO) and 2.6 billion barrels of natural gas liquids (BBNGL) that have the potential to be added to reserves over the next 30 years. Only a fraction of this, however, may be economically recoverable . Of the total estimate of 84.6 TCFG, a mean of 25.78 TCFG is in continuous-type reservoirs in the Mesaverde TPS. The Mesaverde TPS is defined as all reservoirs predominantly containing gas derived from the Mesaverde Group east of the pinchout of the Lewis Shale, which acts as a top seal separating the Mesaverde TPS from the overlying Lewis TPS. Continuous-type reservoirs in the Mesaverde TPS were subdivided into the Almond Continuous Gas Assessment Unit (AU) (mean of 13.35 TCFG), Rock Springs-Ericson Continuous Gas AU (mean of 12.18 TCFG), and the Mesaverde Coalbed Gas AU (mean of 0.25 TCFG). Geologic analysis was used to determine the favorable ?sweet spots? for potential gas resources. The Almond AU has been heavily explored at depths less than 11,000 ft, thus additions to reserves will most likely be the result of infill drilling in existing fields and the discovery of sweet spots at depths greater than 11,000 ft. There is much uncertainty in the size of undiscovered resource in the Rock Springs-Ericson AU because potential reservoirs are only sparsely explored. Only a small fraction of in-place coal-bed gas is considered to be recoverable because of low permeability and problems posed by produced water.

A Statistics-Based Material Property Analysis to Support TPS Characterization

NASA Technical Reports Server (NTRS)

Copeland, Sean R.; Cozmuta, Ioana; Alonso, Juan J.

2012-01-01

Accurate characterization of entry capsule heat shield material properties is a critical component in modeling and simulating Thermal Protection System (TPS) response in a prescribed aerothermal environment. The thermal decomposition of the TPS material during the pyrolysis and charring processes is poorly characterized and typically results in large uncertainties in material properties as inputs for ablation models. These material property uncertainties contribute to large design margins on flight systems and cloud re- construction efforts for data collected during flight and ground testing, making revision to existing models for entry systems more challenging. The analysis presented in this work quantifies how material property uncertainties propagate through an ablation model and guides an experimental test regimen aimed at reducing these uncertainties and characterizing the dependencies between properties in the virgin and charred states for a Phenolic Impregnated Carbon Ablator (PICA) based TPS. A sensitivity analysis identifies how the high-fidelity model behaves in the expected flight environment, while a Monte Carlo based uncertainty propagation strategy is used to quantify the expected spread in the in-depth temperature response of the TPS. An examination of how perturbations to the input probability density functions affect output temperature statistics is accomplished using a Kriging response surface of the high-fidelity model. Simulations are based on capsule configuration and aerothermal environments expected during the Mars Science Laboratory (MSL) entry sequence. We identify and rank primary sources of uncertainty from material properties in a flight-relevant environment, show the dependence on spatial orientation and in-depth location on those uncertainty contributors, and quantify how sensitive the expected results are.

RMS/OBSS inspection of shuttle thermal tile system

NASA Image and Video Library

2011-02-25

S133-E-006073 (25 Feb. 2011) --- Controlled by the STS-133 astronauts inside Discovery's cabin, the Remote Manipulator System/Orbiter Boom Sensor System (RMS/OBSS) equipped with special cameras, begins to conduct thorough inspections of the shuttle’s thermal tile system on flight day 2. Photo credit: NASA or National Aeronautics and Space Administration

Transient thermal analysis of a titanium multiwall thermal protection system

NASA Technical Reports Server (NTRS)

Blosser, M. L.

1982-01-01

The application of the SPAR thermal analyzer to the thermal analysis of a thermal protection system concept is discussed. The titanium multiwall thermal protection system concept consists of alternate flat and dimpled sheets which are joined together at the crests of the dimples and formed into 30 cm by 30 cm (12 in. by 12 in.) tiles. The tiles are mechanically attached to the structure. The complex tile geometry complicates thermal analysis. Three modes of heat transfer were considered: conduction through the gas inside the tile, conduction through the metal, and radiation between the various layers. The voids between the dimpled and flat sheets were designed to be small enough so that natural convection is insignificant (e.g., Grashof number 1000). A two step approach was used in the thermal analysis of the multiwall thermal protection system. First, an effective normal (through-the-thickness) thermal conductivity was obtained from a steady state analysis using a detailed SPAR finite element model of a small symmetric section of the multiwall tile. This effective conductivity was then used in simple one dimensional finite element models for preliminary analysis of several transient heat transfer problems.

Geologic assessment of undiscovered hydrocarbon resources of the Western Oregon and Washington Province

USGS Publications Warehouse

,; Brownfield, Michael E.; Charpentier, Ronald R.; Cook, Troy A.; Klett, Timothy R.; Pollastro, Richard M.; Schenk, Christopher J.; Le, P.A.; ,

2011-01-01

The purpose of the U.S. Geological Survey (USGS) National Oil and Gas Assessment is to develop geology-based hypotheses regarding the potential for additions to oil and gas reserves in priority areas of the United States, focusing on the distribution, quantity, and availability of oil and natural gas resources. The USGS has completed an assessment of the undiscovered, technically recoverable oil and gas resources in western Oregon and Washington (USGS Western Oregon and Washington Province 5004). The province includes all of Oregon and Washington north of the Klamath Mountains and west of the crest of the Cascade Range, and extends offshore to the 3-mi limit of State waters on the west and to the International Boundary in the Straits of Juan de Fuca and Canada on the north. It measures about 450 mi north-south and 50 to 160 mi east-west, encompassing more than 51,000 mi2. The assessment of the Western Oregon and Washington Province is geology based and used the total petroleum system (TPS) concept. The geologic elements of a TPS include hydrocarbon source rocks (source rock maturation and hydrocarbon generation and migration), reservoir rocks (quality and distribution), and traps for hydrocarbon accumulation. Using these geologic criteria, two conventional and one unconventional (continuous) total petroleum systems were defined, with one assessment unit (AU) in each TPS: (1) the Cretaceous-Tertiary Composite TPS and the Western Oregon and Washington Conventional Gas AU, (2) the Tertiary Marine TPS and the Tertiary-Marine Gas AU, and (3) the Tertiary Coalbed Gas TPS and the Eocene Coalbed Gas AU, in which a cell-based methodology was used to estimate coalbed-gas resources.

Sustainable land-use by regional energy and material flow management using "Terra-Preta-Technology

NASA Astrophysics Data System (ADS)

Friede, K.; Rößler, K.; Terytze, K.; Vogel, I.; Worzyk, F.; Schatten, R.; Wagner, R.; Haubold-Rosar, M.; Rademacher, A.; Weiß, U.; Weinfurtner, K.; Drabkin, D.; Zundel, S.; Trabelsi, S.

2012-04-01

The interdisciplinary and transdisciplinary joint research project seeks innovative system solutions for resource efficiency, climate protection and area revaluation by means of an integrative approach. The project's fundament is set by implementing the zero-emission-strategy, launching a regional resource efficient material flow management as well as utilising "Terra-Preta-Technology" as an innovative system component. As the centrepiece of optimised regional biogenic material flows Terra Preta Substrate (TPS) contains biochar shall be utilised exemplarily in model regions. In regional project 1 (state of Brandenburg, county Teltow-Fläming) TPS shall be used on military conversion areas, which are contaminated with polycyclic aromatic hydrocarbons and mineral oil hydrocarbons. It will be examined, whether the use of TPS causes accelerated pollutant reduction and whether this area is available for renewable raw material production. In regional project 2 (Western Lusatia, county Oberspreewald-Lusatia) reclamation and renaturation of post-mining-landscapes is first priority. In this case, the project seeks for an upgrade of devastated soils for plant production as well as for restoration of soil functions and setup of organic soil substances. In regional project 3 (state of North Rhine-Westphalia, city of Schmallenberg) reforestations of large scale windbreakage areas shall be supported by using TPS. Soil stabilisation, increased growth and survival of young trees and decreased nutrient losses are desired achievements. The crop production effectiveness and environmental compatibility of TPS will be determined by tests in laboratories, by lysimeter and open land taking into account chemical and physical as well as biological parameters. Currently diverse chemical, physical and biological examinations are performed. First results will be presented. The focus will be set on the use of TPS on military conversion areas to reduce specific organic contaminations.

Mars 2020 Entry, Descent and Landing Instrumentation (MEDLI2)

NASA Technical Reports Server (NTRS)

Bose, Deepak; Wright, Henry; White, Todd; Schoenenberger, Mark; Santos, Jose; Karlgaard, Chris; Kuhl, Chris; Oishi, TOmo; Trombetta, Dominic

2016-01-01

This paper will introduce Mars Entry Descent and Landing Instrumentation (MEDLI2) on NASA's Mars2020 mission. Mars2020 is a flagship NASA mission with science and technology objectives to help answer questions about possibility of life on Mars as well as to demonstrate technologies for future human expedition. Mars2020 is scheduled for launch in 2020. MEDLI2 is a suite of instruments embedded in the heatshield and backshell thermal protection systems of Mars2020 entry vehicle. The objectives of MEDLI2 are to gather critical aerodynamics, aerothermodynamics and TPS performance data during EDL phase of the mission. MEDLI2 builds up the success of MEDLI flight instrumentation on Mars Science Laboratory mission in 2012. MEDLI instrumentation suite measured surface pressure and TPS temperature on the heatshield during MSL entry into Mars. MEDLI data has since been used for unprecedented reconstruction of aerodynamic drag, vehicle attitude, in-situ atmospheric density, aerothermal heating, transition to turbulence, in-depth TPS performance and TPS ablation. [1,2] In addition to validating predictive models, MEDLI data has highlighted extra margin available in the MSL forebody TPS, which can potentially be used to reduce vehicle parasitic mass. MEDLI2 expands the scope of instrumentation by focusing on quantities of interest not addressed in MEDLI suite. The type the sensors are expanded and their layout on the TPS modified to meet these new objectives. The paper will provide key motivation and governing requirements that drive the choice and the implementation of the new sensor suite. The implementation considerations of sensor selection, qualification, and demonstration of minimal risk to the host mission will be described. The additional challenges associated with mechanical accommodation, electrical impact, data storage and retrieval for MEDLI2 system, which extends sensors to backshell will also be described.

Generation of Escher Arts with Dual Perception.

PubMed

Lin, Shih-Syun; Morace, Charles C; Lin, Chao-Hung; Hsu, Li-Fong; Lee, Tong-Yee

2018-02-01

Escher transmutation is a graphic art that smoothly transforms one tile pattern into another tile pattern with dual perception. A classic example is the artwork called Sky and Water, in which a compelling figure-ground arrangement is applied to portray the transmutation of a bird in sky and a fish in water. The shape of a bird is progressively deformed and dissolves into the background while the background gradually reveals the shape of a fish. This paper introduces a system to create a variety of Escher-like transmutations, which includes the algorithms for initializing a tile pattern with dual figure-ground arrangement, for searching for the best matched shape of a user-specified motif from a database, and for transforming the content and shapes of tile patterns using a content-aware warping technique. The proposed system, integrating the graphic techniques of tile initialization, shape matching, and shape warping, allows users to create various Escher-like transmutations with minimal user interaction. Experimental results and conducted user studies demonstrate the feasibility and flexibility of the proposed system in Escher art generation.

Navigating the socio-bio-geo-chemistry and engineering of nitrogen management in two illinois tile-drained watersheds.

PubMed

David, Mark B; Flint, Courtney G; Gentry, Lowell E; Dolan, Mallory K; Czapar, George F; Cooke, Richard A; Lavaire, Tito

2015-03-01

Reducing nitrate loads from corn and soybean, tile-drained, agricultural production systems in the Upper Mississippi River basin is a major challenge that has not been met. We evaluated a range of possible management practices from biophysical and social science perspectives that could reduce nitrate losses from tile-drained fields in the Upper Salt Fork and Embarras River watersheds of east-central Illinois. Long-term water quality monitoring on these watersheds showed that nitrate losses averaged 30.6 and 23.0 kg nitrate N ha yr (Embarras and Upper Salt Fork watersheds, respectively), with maximum nitrate concentrations between 14 and 18 mg N L. With a series of on-farm studies, we conducted tile monitoring to evaluate several possible nitrate reduction conservation practices. Fertilizer timing and cover crops reduced nitrate losses (30% reduction in a year with large nitrate losses), whereas drainage water management on one tile system demonstrated the problems with possible retrofit designs (water flowed laterally from the drainage water management tile to the free drainage system nearby). Tile woodchip bioreactors had good nitrate removal in 2012 (80% nitrate reduction), and wetlands had previously been shown to remove nitrate (45% reductions) in the Embarras watershed. Interviews and surveys indicated strong environmental concern and stewardship ethics among landowners and farmers, but the many financial and operational constraints that they operate under limited their willingness to adopt conservation practices that targeted nitrate reduction. Under the policy and production systems currently in place, large-scale reductions in nitrate losses from watersheds such as these in east-central Illinois will be difficult. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Quantitative real-time PCR-based assessment of tile drainage management influences on bacterial pathogens in tile drainage and groundwater.

PubMed

Liu, Linda; Cloutier, Michel; Craiovan, Emilia; Edwards, Mark; Frey, Steven K; Gottschall, Natalie; Lapen, David R; Sunohara, Mark; Topp, Edward; Khan, Izhar U H

2018-05-15

This study compared the impact of controlled tile drainage (CD) and freely draining (FD) systems on the prevalence and quantitative real-time PCR-based enumeration of four major pathogens including Arcobacter butzleri, Campylobacter jejuni, Campylobacter coli, and Helicobacter pylori in tile- and groundwater following a fall liquid swine manure (LSM) application on clay loam field plots. Although the prevalence of all target pathogens were detected in CD and FD systems, the loads of A. butzleri, C. jejuni, and C. coli were significantly lower in CD tile-water (p<0.05), in relation to FD tile-water. However, concentrations of A. butzleri were significantly greater in CD than FD tile-water (p<0.05). In shallow groundwater (1.2m depth), concentrations of A. butzleri, C. coli, and H. pylori showed no significant difference between CD and FD plots, while C. jejuni concentrations were significantly higher in FD plots (p<0.05). No impact of CD on the H. pylori was observed since quantitative detection in tile- and groundwater was scarce. Although speculative, H. pylori occurrence may have been related to the application of municipal biosolids four years prior to the LSM experiment. Overall, CD can be used to help minimize off-field export of pathogens into surface waters following manure applications to land, thereby reducing waterborne pathogen exposure risks to humans. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Reducing phosphorus loss in tile water with managed drainage in a claypan soil.

PubMed

Nash, Patrick R; Nelson, Kelly A; Motavalli, Peter P; Nathan, Manjula; Dudenhoeffer, Chris

2015-03-01

Installing subsurface tile drain systems in poorly drained claypan soils to improve corn ( L.) yields could potentially increase environmental phosphorus (P) loss through the tile drainage system. The objectives of the study were to quantify the average concentration and loss of ortho-P in tile drain water from a claypan soil and to determine whether managed subsurface drainage (MD) could reduce ortho-P loss in tile water compared with free subsurface drainage (FD). Flow-weighted ortho-P concentration in the tile water was significantly lower with MD (0.09 mg L) compared with that of FD (0.15 mg L). Ortho-P loss in the tile water of this study was reduced with MD (36 g ha) by 80% compared with FD (180 g ha). Contrary to previous research, reduced ortho-P loss observed over the 4-yr study was not solely due to the reduced amount of water drained annually (63%) with MD compared with FD. During the spring period, when flow was similar between MD and FD, the concentration of ortho-P in the tile water generally was lower with MD compared with FD, which resulted in significantly less ortho-P loss with MD. We speculate that MD's ability to conserve water during the dry summer months increased corn's uptake of water and P, which reduced the amount of P available for leaching loss in the subsequent springs. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Thermal Structures Technology Development for Reusable Launch Vehicle Cryogenic Propellant Tanks

NASA Technical Reports Server (NTRS)

Johnson, Theodore F.; Natividad, Roderick; Rivers, H. Kevin; Smith, Russell

1998-01-01

Analytical and experimental studies conducted at the NASA Langley Research Center for investigating integrated cryogenic propellant tank systems for a Reusable Launch Vehicle are described. The cryogenic tanks are investigated as an integrated tank system. An integrated tank system includes the tank wall, cryogenic insulation, Thermal Protection System (TPS) attachment sub-structure, and TPS. Analysis codes are used to size the thicknesses of cryogenic insulation and TPS insulation for thermal loads, and to predict tank buckling strengths at various ring frame spacings. The unique test facilities developed for the testing of cryogenic tank components are described. Testing at cryogenic and high-temperatures verifies the integrity of materials, design concepts, manufacturing processes, and thermal/structural analyses. Test specimens ranging from the element level to the subcomponent level are subjected to projected vehicle operational mechanical loads and temperatures. The analytical and experimental studies described in this paper provide a portion of the basic information required for the development of light-weight reusable cryogenic propellant tanks.

Thermal Structures Technology Development for Reusable Launch Vehicle Cryogenic Propellant Tanks

NASA Technical Reports Server (NTRS)

Johnson, Theodore F.; Natividad, Roderick; Rivers, H. Kevin; Smith, Russell W.

2005-01-01

Analytical and experimental studies conducted at the NASA, Langley Research Center (LaRC) for investigating integrated cryogenic propellant tank systems for a reusable launch vehicle (RLV) are described. The cryogenic tanks are investigated as an integrated tank system. An integrated tank system includes the tank wall, cryogenic insulation, thermal protection system (TPS) attachment sub-structure, and TPS. Analysis codes are used to size the thicknesses of cryogenic insulation and TPS insulation for thermal loads, and to predict tank buckling strengths at various ring frame spacings. The unique test facilities developed for the testing of cryogenic tank components are described. Testing at cryogenic and high-temperatures verifies the integrity of materials, design concepts, manufacturing processes, and thermal/structural analyses. Test specimens ranging from the element level to the subcomponent level are subjected to projected vehicle operational mechanical loads and temperatures. The analytical and experimental studies described in this paper provide a portion of the basic information required for the development of light-weight reusable cryogenic propellant tanks.

Emission and Accumulation of Monoterpene and the Key Terpene Synthase (TPS) Associated with Monoterpene Biosynthesis in Osmanthus fragrans Lour.

PubMed

Zeng, Xiangling; Liu, Cai; Zheng, Riru; Cai, Xuan; Luo, Jing; Zou, Jingjing; Wang, Caiyun

2015-01-01

Osmanthus fragrans is an ornamental and economically important plant known for its magnificent aroma, and the most important aroma-active compounds in flowers are monoterpenes, mainly β-ocimene, linalool and linalool derivatives. To understand the molecular mechanism of monoterpene production, we analyzed the emission and accumulation patterns of these compounds and the transcript levels of the genes involved in their biosynthesis in two O. fragrans cultivars during flowering stages. The results showed that both emission and accumulation of monoterpenes varied with flower development and glycosylation had an important impact on floral linalool emission during this process. Gene expression demonstrated that the transcript levels of terpene synthase (TPS) genes probably played a key role in monoterpene production, compared to the genes in the MEP pathway. Phylogenetic analysis showed that OfTPS1 and OfTPS2 belonged to a TPS-g subfamily, and OfTPS3 and OfTPS4 clustered into a TPS-b subfamily. Their transient and stable expression in tobacco leaves suggested that OfTPS1 and OfTPS2 exclusively produced β-linalool, and trans-β-ocimene was the sole product from OfTPS3, while OfTPS4, a predictive sesquiterpene synthase, produced α-farnesene. These results indicate that OfTPS1, OfTPS2, and OfTPS3 could account for the major floral monoterpenes, linalool and trans-β-ocimene, produced in O. fragrans flowers.

Emission and Accumulation of Monoterpene and the Key Terpene Synthase (TPS) Associated with Monoterpene Biosynthesis in Osmanthus fragrans Lour

PubMed Central

Zeng, Xiangling; Liu, Cai; Zheng, Riru; Cai, Xuan; Luo, Jing; Zou, Jingjing; Wang, Caiyun

2016-01-01

Osmanthus fragrans is an ornamental and economically important plant known for its magnificent aroma, and the most important aroma-active compounds in flowers are monoterpenes, mainly β-ocimene, linalool and linalool derivatives. To understand the molecular mechanism of monoterpene production, we analyzed the emission and accumulation patterns of these compounds and the transcript levels of the genes involved in their biosynthesis in two O. fragrans cultivars during flowering stages. The results showed that both emission and accumulation of monoterpenes varied with flower development and glycosylation had an important impact on floral linalool emission during this process. Gene expression demonstrated that the transcript levels of terpene synthase (TPS) genes probably played a key role in monoterpene production, compared to the genes in the MEP pathway. Phylogenetic analysis showed that OfTPS1 and OfTPS2 belonged to a TPS-g subfamily, and OfTPS3 and OfTPS4 clustered into a TPS-b subfamily. Their transient and stable expression in tobacco leaves suggested that OfTPS1 and OfTPS2 exclusively produced β-linalool, and trans-β-ocimene was the sole product from OfTPS3, while OfTPS4, a predictive sesquiterpene synthase, produced α-farnesene. These results indicate that OfTPS1, OfTPS2, and OfTPS3 could account for the major floral monoterpenes, linalool and trans-β-ocimene, produced in O. fragrans flowers. PMID:26793212

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ellefson, S; Department of Human Oncology, University of Wisconsin, Madison, WI; Culberson, W

Purpose: Discrepancies in absolute dose values have been detected between the ViewRay treatment planning system and ArcCHECK readings when performing delivery quality assurance on the ViewRay system with the ArcCHECK-MR diode array (SunNuclear Corporation). In this work, we investigate whether these discrepancies are due to errors in the ViewRay planning and/or delivery system or due to errors in the ArcCHECK’s readings. Methods: Gamma analysis was performed on 19 ViewRay patient plans using the ArcCHECK. Frequency analysis on the dose differences was performed. To investigate whether discrepancies were due to measurement or delivery error, 10 diodes in low-gradient dose regions weremore » chosen to compare with ion chamber measurements in a PMMA phantom with the same size and shape as the ArcCHECK, provided by SunNuclear. The diodes chosen all had significant discrepancies in absolute dose values compared to the ViewRay TPS. Absolute doses to PMMA were compared between the ViewRay TPS calculations, ArcCHECK measurements, and measurements in the PMMA phantom. Results: Three of the 19 patient plans had 3%/3mm gamma passing rates less than 95%, and ten of the 19 plans had 2%/2mm passing rates less than 95%. Frequency analysis implied a non-random error process. Out of the 10 diode locations measured, ion chamber measurements were all within 2.2% error relative to the TPS and had a mean error of 1.2%. ArcCHECK measurements ranged from 4.5% to over 15% error relative to the TPS and had a mean error of 8.0%. Conclusion: The ArcCHECK performs well for quality assurance on the ViewRay under most circumstances. However, under certain conditions the absolute dose readings are significantly higher compared to the planned doses. As the ion chamber measurements consistently agree with the TPS, it can be concluded that the discrepancies are due to ArcCHECK measurement error and not TPS or delivery system error. This work was funded by the Bhudatt Paliwal Professorship and the University of Wisconsin Medical Radiation Research Center.« less

The organ-specific expression of terpene synthase genes contributes to the terpene hydrocarbon composition of chamomile essential oils

PubMed Central

2012-01-01

Background The essential oil of chamomile, one of the oldest and agronomically most important medicinal plant species in Europe, has significant antiphlogistic, spasmolytic and antimicrobial activities. It is rich in chamazulene, a pharmaceutically active compound spontaneously formed during steam distillation from the sesquiterpene lactone matricine. Chamomile oil also contains sesquiterpene alcohols and hydrocarbons which are produced by the action of terpene synthases (TPS), the key enzymes in constructing terpene carbon skeletons. Results Here, we present the identification and characterization of five TPS enzymes contributing to terpene biosynthesis in chamomile (Matricaria recutita). Four of these enzymes were exclusively expressed in above-ground organs and produced the common terpene hydrocarbons (−)-(E)-β-caryophyllene (MrTPS1), (+)-germacrene A (MrTPS3), (E)-β-ocimene (MrTPS4) and (−)-germacrene D (MrTPS5). A fifth TPS, the multiproduct enzyme MrTPS2, was mainly expressed in roots and formed several Asteraceae-specific tricyclic sesquiterpenes with (−)-α-isocomene being the major product. The TPS transcript accumulation patterns in different organs of chamomile were consistent with the abundance of the corresponding TPS products isolated from these organs suggesting that the spatial regulation of TPS gene expression qualitatively contribute to terpene composition. Conclusions The terpene synthases characterized in this study are involved in the organ-specific formation of essential oils in chamomile. While the products of MrTPS1, MrTPS2, MrTPS4 and MrTPS5 accumulate in the oils without further chemical alterations, (+)-germacrene A produced by MrTPS3 accumulates only in trace amounts, indicating that it is converted into another compound like matricine. Thus, MrTPS3, but also the other TPS genes, are good markers for further breeding of chamomile cultivars rich in pharmaceutically active essential oils. PMID:22682202

KSC-05pd2513

NASA Image and Video Library

2005-11-19

KENNEDY SPACE CENTER, FLA. - Inside the RLV Hangar at NASA Kennedy Space Center, employees prepare a blanket sewing machine to be transferred back to the Thermal Protection System (TPS) facility. The upper floor of the facility, where soft material was processed, was damaged during the 2004 hurricanes. While the TPS facility was being repaired, normal work activity was done in the hangar.

Earth Entry Requirements for Mars, Europa and Enceladus Sample Return Missions: A Thermal Protection System Perspective

NASA Technical Reports Server (NTRS)

Venkatapathy, Ethiraj; Gage, Peter; Ellerby, Don; Mahzari, Milad; Peterson, Keith; Stackpoole, Mairead; Young, Zion

2016-01-01

This oral presentation will be given at the 13th International Planetary Probe Workshop on June 14th, 2016 and will cover the drivers for reliability and the challenges faced in selecting and designing the thermal protection system (TPS). In addition, an assessment is made on new emerging TPS related technologies that could help with designs to meet the planetary protection requirements to prevent backward (Earth) contamination by biohazardous samples.

The level of sugars and synthesis of trehalose in Ascaris suum tissues.

PubMed

Dmitryjuk, M; Łopieńska-Biernat, E; Farjan, M

2009-09-01

The activities of trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP) were observed in muscles, individual parts of the reproductive system and haemolymph of Ascaris suum. The highest activity of TPS was detected in the upper uterus, while the lowest activity of TPS was detected in the ovary and oviduct of the nematode. Relatively high activity was detected in muscles, haemolymph and two remaining parts of the uterus. The TPP activity was the highest in lower length of the uterus, following muscles, ovary, central and upper uterus. The lowest activity of TPP was detected in the haemolymph and oviduct of A. suum. Besides TPS and TPP, trehalose was also detected in the studied tissues except the cuticle and the intestine. Glucose was present in all organs, but the highest concentration was found in the cuticle and intestine.

Thermal Protection Materials: Development, Characterization and Evaluation

NASA Technical Reports Server (NTRS)

Johnson, Silvia M.

2012-01-01

Thermal protection materials and systems (TPS) are used to protect space vehicles from the heat experienced during entry into an atmosphere. The application for these materials is very specialized as are the materials. They must have specific properties to withstand conditions during specific entries. There is no one-size-fits-all TPS as the conditions experienced by a material are very dependent upon the atmosphere, the entry speed, the size and shape of the vehicle, and the location on the vehicle. However, all TPS must be reliable and efficient to ensure mission safety, that is to protect the vehicle while ensuring that payload is maximized. Types of TPS will be reviewed in relation to types of missions and applications. Both reusable and ablative materials will be discussed. Approaches to characterizing and evaluating these materials will be presented. The role of heritage versus new materials will be described.

Development of Wireless Subsurface Microsensors for Health Monitoring of Thermal Protection Systems

NASA Technical Reports Server (NTRS)

Pallix, Joan; Milos, Frank; Arnold, James O. (Technical Monitor)

2000-01-01

Low cost access to space is a primary goal for both NASA and the U.S. aerospace industry. Integrated subsystem health diagnostics is an area where major improvements have been identified for potential implementation into the design of new reusable launch vehicles (RLVS) in order to reduce life cycle costs, increase safety margins and improve mission reliability. A number of efforts are underway to use existing and emerging technologies to establish new methods for vehicle health monitoring on operational vehicles as well as X-vehicles. This paper summarizes a joint effort between several NASA centers and industry partners to develop rapid wireless diagnostic tools for failure management and long-term TPS performance monitoring of thermal protection systems (TPS) on future RLVS. An embedded wireless microsensor suite is being designed to allow rapid subsurface TPS health monitoring and damage assessment. This sensor suite will consist of both passive overlimit sensors and sensors for continuous parameter monitoring in flight. The on-board diagnostic system can be used to radio in maintenance requirements before landing and the data could also be used to assist in design validation for X-vehicles. For a 3rd generation vehicle, wireless diagnostics should be at a stage of technical development that will allow use for intelligent feedback systems for guidance and navigation control applications and can also serve as feedback for TPS that can intelligently adapt to its environment.

Metallic Thermal Protection System Technology Development: Concepts, Requirements and Assessment Overview

NASA Technical Reports Server (NTRS)

Dorsey, John T.; Poteet, Carl C.; Chen, Roger R.; Wurster, Kathryn E.

2002-01-01

A technology development program was conducted to evolve an earlier metallic thermal protection system (TPS) panel design, with the goals of: improving operations features, increasing adaptability (ease of attaching to a variety of tank shapes and structural concepts), and reducing weight. The resulting Adaptable Robust Metallic Operable Reusable (ARMOR) TPS system incorporates a high degree of design flexibility (allowing weight and operability to be traded and balanced) and can also be easily integrated with a large variety of tank shapes, airframe structural arrangements and airframe structure/material concepts. An initial attempt has been made to establish a set of performance based TPS design requirements. A set of general (FARtype) requirements have been proposed, focusing on defining categories that must be included for a comprehensive design. Load cases required for TPS design must reflect the full flight envelope, including a comprehensive set of limit loads, However, including additional loads. such as ascent abort trajectories, as ultimate load cases, and on-orbit debris/micro-meteoroid hypervelocity impact, as one of the discrete -source -damage load cases, will have a significant impact on system design and resulting performance, reliability and operability. Although these load cases have not been established, they are of paramount importance for reusable vehicles, and until properly included, all sizing results and assessments of reliability and operability must be considered optimistic at a minimum.

NDE of the space shuttle orbiter thermal protection system: Phase 2 final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tow, D.M.; Barna, B.A.; Rodriguez, J.G.

1989-03-01

Research continued on the development of a nondestructive evaluation technique for inspecting bonds on the space shuttle orbiter thermal protection system tiles. The approach taken uses a noncontacting laser sensor to measure the vibrational response of bonded tiles to acoustical excitation. Laboratory work concentrated on investigating the dynamic response of ''acreage'' tiles, i.e., tiles covering the underside of the orbiter, all approximately square. A number of promising unbond signatures have been identified in the time and frequency domain response. Field tests were conducted to study environmental effects on the techniques being developed. The ambient motion of the orbiter was foundmore » to be larger than expected, necessitating modifications to current techniques. 2 refs., 21 figs., 1 tab.« less

In-Flight Aeroelastic Stability of the Thermal Protection System on the NASA HIAD, Part I: Linear Theory

NASA Technical Reports Server (NTRS)

Goldman, Benjamin D.; Dowell, Earl H.; Scott, Robert C.

2014-01-01

Conical shell theory and piston theory aerodynamics are used to study the aeroelastic stability of the thermal protection system (TPS) on the NASA Hypersonic Inflatable Aerodynamic Decelerator (HIAD). Structural models of the TPS consist of single or multiple orthotropic conical shell systems resting on several circumferential linear elastic supports. The shells in each model may have pinned (simply-supported) or elastically-supported edges. The Lagrangian is formulated in terms of the generalized coordinates for all displacements and the Rayleigh-Ritz method is used to derive the equations of motion. The natural modes of vibration and aeroelastic stability boundaries are found by calculating the eigenvalues and eigenvectors of a large coefficient matrix. When the in-flight configuration of the TPS is approximated as a single shell without elastic supports, asymmetric flutter in many circumferential waves is observed. When the elastic supports are included, the shell flutters symmetrically in zero circumferential waves. Structural damping is found to be important in this case. Aeroelastic models that consider the individual TPS layers as separate shells tend to flutter asymmetrically at high dynamic pressures relative to the single shell models. Several parameter studies also examine the effects of tension, orthotropicity, and elastic support stiffness.

Increased urinary levels of tissue polypeptide specific antigen (TPS) in alcoholics.

PubMed

Barros, Paula; Gonzalez-Quintela, Arturo; Mella, Carmen; Perez, Luis-Fernando

2006-01-01

Urinary levels of tissue polypeptide specific antigen (TPS, cytokeratin-18) have been proposed as a marker of urothelial malignancies. Previous studies have shown that serum TPS levels are elevated in alcoholics. This study was designed to determine whether alcoholics had elevated urinary TPS levels as well. Serum and urinary TPS levels were determined in 24 alcoholics and 15 healthy controls by means of a commercial chemiluminiscent immunoassay. Serum TPS levels were higher in alcoholics than in controls (median 332 U/L, range 51-21241 U/L versus median 17 U/L, range 15-65 U/L, respectively, p<0.001). Urinary TPS levels were also higher in alcoholics than in controls (median 244 U/L, range 22-1267 U/L versus median 66.5 U/L, range 15-600 U/L, respectively, p=0.001). Urinary TPS levels were correlated with serum TPS levels in alcoholics. Urinary TPS levels are elevated in alcoholics. Consequently, the specificity of urinary TPS as a tumor marker may be limited in alcoholics.

The influence of the free space environment on the superlight-weight thermal protection system: conception, methods, and risk analysis

NASA Astrophysics Data System (ADS)

Yatsenko, Vitaliy; Falchenko, Iurii; Fedorchuk, Viktor; Petrushynets, Lidiia

2016-07-01

This report focuses on the results of the EU project "Superlight-weight thermal protection system for space application (LIGHT-TPS)". The bottom line is an analysis of influence of the free space environment on the superlight-weight thermal protection system (TPS). This report focuses on new methods that based on the following models: synergetic, physical, and computational. This report concentrates on four approaches. The first concerns the synergetic approach. The synergetic approach to the solution of problems of self-controlled synthesis of structures and creation of self-organizing technologies is considered in connection with the super-problem of creation of materials with new functional properties. Synergetics methods and mathematical design are considered according to actual problems of material science. The second approach describes how the optimization methods can be used to determine material microstructures with optimized or targeted properties. This technique enables one to find unexpected microstructures with exotic behavior (e.g., negative thermal expansion coefficients). The third approach concerns the dynamic probabilistic risk analysis of TPS l elements with complex characterizations for damages using a physical model of TPS system and a predictable level of ionizing radiation and space weather. Focusing is given mainly on the TPS model, mathematical models for dynamic probabilistic risk assessment and software for the modeling and prediction of the influence of the free space environment. The probabilistic risk assessment method for TPS is presented considering some deterministic and stochastic factors. The last approach concerns results of experimental research of the temperature distribution on the surface of the honeycomb sandwich panel size 150 x 150 x 20 mm at the diffusion welding in vacuum are considered. An equipment, which provides alignment of temperature fields in a product for the formation of equal strength of welded joints is considered. Many tasks in computational materials science can be posed as optimization problems. This technique enables one to find unexpected microstructures with exotic behavior (e.g., negative thermal expansion coefficients). The last approach is concerned with the generation of realizations of materials with specified but limited microstructural information: an intriguing inverse problem of both fundamental and practical importance. Computational models based upon the theories of molecular dynamics or quantum mechanics would enable the prediction and modification of fundamental materials properties. This problem is solved using deterministic and stochastic optimization techniques. The main optimization approaches in the frame of the EU project "Superlight-weight thermal protection system for space application" are discussed. Optimization approach to the alloys for obtaining materials with required properties using modeling techniques and experimental data will be also considered. This report is supported by the EU project "Superlight-weight thermal protection system for space application (LIGHT-TPS)"

Orbiter thermal pressure drop characteristics for shuttle orbiter thermal protection system components: High density tile, low density tile, densified low density tile, and strain isolation pad

NASA Technical Reports Server (NTRS)

Lawing, P. L.; Nystrom, D. M.

1980-01-01

Pressure drop tests were conducted on available samples of low and high density tile, densified low density tile, and strain isolation pads. The results are presented in terms of pressure drop, material thickness and volume flow rate. Although the test apparatus was only capable of a small part of the range of conditions to be encountered in a Shuttle Orbiter flight, the data serve to determine the type of flow characteristics to be expected for each material type tested; the measured quantities also should serve as input for initial venting and flow through analysis.

Preparation and Oxidation Stability Evaluation of Tea Polyphenols-Loaded Inverse Micro-Emulsion.

PubMed

Lan, Xiaohong; Sun, Jingjing; Yang, Ying; Chen, Mengjie; Liu, Jianhua; Wu, Jinhong; Wang, Zhengwu

2017-05-01

Compared to synthetic antioxidants, tea polyphenols (TPs) has its own advantages in edible oil industry, however, the hydrophilic properties have restricted its applications. In this study, the ternary phase diagram of TPs-loaded micro-emulsion (ME) system was constructed, in which glyceryl monooleate (GMO), Tween80, linoleic acid as the surfactants, ethanol as the co-surfactant and soybean, corn, sunflower oil as the oil phase, have been used for the preparation of ME. The results indicated that a composition of ME (57.5% oil, 18% Tween80, 18% GMO, 4% Linolic acid, and 2.5% water+ethanol) could dissolve maximum water and could stable for 2 mo at room temperature with an average diameter of 6 to 7 nm, as detected by means of dynamic light scattering (DLS). The loaded of TPs into ME led to an increase of particle size to 15 to 16 nm, due to increased polarity of the water phase. The antioxidant capacity of TPs in ME was characterized by the peroxide value (POV) method. The addition of 1% water phase with 0.1 g/mL TPs could retain the POV at low value for 30 d at accelerating temperature 50 °C. Meanwhile, comparing the three edible oil, ME with corn oil has lower conductivity and higher value of POV during the storage. This work provides an efficient and environmentally friendly approach for the preparation of TPs-loaded ME, which is beneficial to the application of TPs in edible oil. © 2017 Institute of Food Technologists®.

Self assembly of rectangular shapes on concentration programming and probabilistic tile assembly models

PubMed Central

Rajasekaran, Sanguthevar

2013-01-01

Efficient tile sets for self assembling rectilinear shapes is of critical importance in algorithmic self assembly. A lower bound on the tile complexity of any deterministic self assembly system for an n × n square is Ω(log(n)log(log(n))) (inferred from the Kolmogrov complexity). Deterministic self assembly systems with an optimal tile complexity have been designed for squares and related shapes in the past. However designing Θ(log(n)log(log(n))) unique tiles specific to a shape is still an intensive task in the laboratory. On the other hand copies of a tile can be made rapidly using PCR (polymerase chain reaction) experiments. This led to the study of self assembly on tile concentration programming models. We present two major results in this paper on the concentration programming model. First we show how to self assemble rectangles with a fixed aspect ratio (α:β), with high probability, using Θ(α + β) tiles. This result is much stronger than the existing results by Kao et al. (Randomized self-assembly for approximate shapes, LNCS, vol 5125. Springer, Heidelberg, 2008) and Doty (Randomized self-assembly for exact shapes. In: proceedings of the 50th annual IEEE symposium on foundations of computer science (FOCS), IEEE, Atlanta. pp 85–94, 2009)—which can only self assembly squares and rely on tiles which perform binary arithmetic. On the other hand, our result is based on a technique called staircase sampling. This technique eliminates the need for sub-tiles which perform binary arithmetic, reduces the constant in the asymptotic bound, and eliminates the need for approximate frames (Kao et al. Randomized self-assembly for approximate shapes, LNCS, vol 5125. Springer, Heidelberg, 2008). Our second result applies staircase sampling on the equimolar concentration programming model (The tile complexity of linear assemblies. In: proceedings of the 36th international colloquium automata, languages and programming: Part I on ICALP ’09, Springer-Verlag, pp 235–253, 2009), to self assemble rectangles (of fixed aspect ratio) with high probability. The tile complexity of our algorithm is Θ(log(n)) and is optimal on the probabilistic tile assembly model (PTAM)—n being an upper bound on the dimensions of a rectangle. PMID:24311993

Color machine vision system for process control in the ceramics industry

NASA Astrophysics Data System (ADS)

Penaranda Marques, Jose A.; Briones, Leoncio; Florez, Julian

1997-08-01

This paper is focused on the design of a machine vision system to solve a problem found in the manufacturing process of high quality polished porcelain tiles. This consists of sorting the tiles according to the criteria 'same appearance to the human eye' or in other words, by color and visual texture. In 1994 this problem was tackled and led to a prototype which became fully operational at production scale in a manufacturing plant, named Porcelanatto, S.A. The system has evolved and has been adapted to meet the particular needs of this manufacturing company. Among the main issues that have been improved, it is worth pointing out: (1) improvement to discern subtle variations in color or texture, which are the main features of the visual appearance; (2) inspection time reduction, as a result of algorithm optimization and the increasing computing power. Thus, 100 percent of the production can be inspected, reaching a maximum of 120 tiles/sec.; (3) adaptation to the different types and models of tiles manufactured. The tiles vary not only in their visible patterns but also in dimensions, formats, thickness and allowances. In this sense, one major problem has been reaching an optimal compromise: The system must be sensitive enough to discern subtle variations in color, but at the same time insensitive thickness variations in the tiles. The following parts have been used to build the system: RGB color line scan camera, 12 bits per channel, PCI frame grabber, PC, fiber optic based illumination and the algorithm which will be explained in section 4.

Fiber Optic Temperature Sensors in TPS: Arc Jet Model Design & Testing

NASA Technical Reports Server (NTRS)

Black, Richard; Feldman, Jay; Ellerby, Donald; Monk, Joshua; Moslehi, Behzad; Oblea, Levy; Switzer, Matthew

2017-01-01

Techniques for using fiber optics with Fiber Bragg Gratings (FBGs) have been developed by IFOS Corp. for use in thermal protection systems (TPS) on spacecraft heat shield materials through NASA Phase 1 and 2 SBIR efforts and have been further improved in a recent collaboration between IFOS and NASA that will be described here. Fiber optic temperature sensors offer several potential advantages over traditional thermocouple sensors including a) multiplexing many sensors in a single fiber to increase sensor density in a given array or to provide spatial resolution, b) improved thermal property match between sensor and TPS to reduce heat flow disruption, c) lack of electrical conductivity.

Debris/Ice/TPS Assessment and Photographic Analysis for Shuttle Mission STS-39

NASA Technical Reports Server (NTRS)

Katnik, Gregory N.; Higginbotham, Scott A.; Davis, J. Bradley

1991-01-01

A Debris/Ice/TPS (thermal protection system) assessment and photographic analysis was conducted for Space Shuttle Mission STS-39. Debris inspections of the flight elements and launch pad were performed before and after launch. Ice/frost conditions on the external tank were assessed by the use of computer programs, nomographs, and infrared scanner data during cryogenic loading of the vehicle followed by on-pad visual inspection. High speed photography of launch was analyzed to identify ice/debris anomalies. The debris/ice/TPS conditions and photographic analysis of Mission STS-39, and their overall effect on the Space Shuttle Program are documented.

Thermal and heat flow instrumentation for the space shuttle Thermal Protection System

NASA Technical Reports Server (NTRS)

Hartman, G. J.; Neuner, G. J.; Pavlosky, J.

1974-01-01

The 100 mission lifetime requirement for the space shuttle orbiter vehicle dictates a unique set of requirements for the Thermal Protection System (TPS) thermal and heat flow instrumentation. This paper describes the design and development of such instrumentation with emphasis on assessment of the accuracy of the measurements when the instrumentation is an integral part of the TPS. The temperature and heat flow sensors considered for this application are described and the optimum choices discussed. Installation techniques are explored and the resulting impact on the system error defined.

Comparison of performance of tile drainage routines in SWAT 2009 and 2012 in an extensively tile-drained watershed in the Midwest

NASA Astrophysics Data System (ADS)

Guo, Tian; Gitau, Margaret; Merwade, Venkatesh; Arnold, Jeffrey; Srinivasan, Raghavan; Hirschi, Michael; Engel, Bernard

2018-01-01

Subsurface tile drainage systems are widely used in agricultural watersheds in the Midwestern US and enable the Midwest area to become highly productive agricultural lands, but can also create environmental problems, for example nitrate-N contamination associated with drainage waters. The Soil and Water Assessment Tool (SWAT) has been used to model watersheds with tile drainage. SWAT2012 revisions 615 and 645 provide new tile drainage routines. However, few studies have used these revisions to study tile drainage impacts at both field and watershed scales. Moreover, SWAT2012 revision 645 improved the soil moisture based curve number calculation method, which has not been fully tested. This study used long-term (1991-2003) field site and river station data from the Little Vermilion River (LVR) watershed to evaluate performance of tile drainage routines in SWAT2009 revision 528 (the old routine) and SWAT2012 revisions 615 and 645 (the new routine). Both the old and new routines provided reasonable but unsatisfactory (NSE < 0.5) uncalibrated flow and nitrate loss results for a mildly sloped watershed with low runoff. The calibrated monthly tile flow, surface flow, nitrate-N in tile and surface flow, sediment and annual corn and soybean yield results from SWAT with the old and new tile drainage routines were compared with observed values. Generally, the new routine provided acceptable simulated tile flow (NSE = 0.48-0.65) and nitrate in tile flow (NSE = 0.48-0.68) for field sites with random pattern tile and constant tile spacing, while the old routine simulated tile flow and nitrate in tile flow results for the field site with constant tile spacing were unacceptable (NSE = 0.00-0.32 and -0.29-0.06, respectively). The new modified curve number calculation method in revision 645 (NSE = 0.50-0.81) better simulated surface runoff than revision 615 (NSE = -0.11-0.49). The calibration provided reasonable parameter sets for the old and new routines in the LVR watershed, and the validation results showed that the new routine has the potential to accurately simulate hydrologic processes in mildly sloped watersheds.

Performance of LI-1542 reusable surface insulation system in a hypersonic stream

NASA Technical Reports Server (NTRS)

Hunt, L. R.; Shideler, J. L.; Weinstein, I.

1976-01-01

The thermal and structural performance LI-1542 reusable surface insulation (RSI) tiles was investigated. The test panel was designed to represent part of the surface structure on a space shuttle orbiter fuselage along a 1250 K isotherm. Aerothermal tests were conducted at a free-stream Mach number of 6.6, a total temperature of 1820 K, Reynolds numbers of 2 millon and 5 million per meter, and dynamic pressures of 26 and 65 kPa. The RSI tiles demonstrated good thermal protection and structural integrity. High temperatures were caused by misalinement in tile height, offset the tile longitudinal alinement, and leakage around thermal seals when differential pressure existed across the panel. The damage tolerance of LI-1542 RSI appeared high. The tile coating crazed early in the test program, but this did not effect the tile integrity. Erosion of the tile edges occurred at forward-facing steps and at the ends of longitudinal gaps because of particle impacts and flow shear.

Some space shuttle tile/strain-isolator-pad sinusoidal vibration tests

NASA Technical Reports Server (NTRS)

Miserentino, R.; Pinson, L. D.; Leadbetter, S. A.

1980-01-01

Vibration tests were performed on the tile/strain-isolator-pad system used as thermal protection for the space shuttle orbiter. Experimental data on normal and in-plane vibration response and damping properties are presented. Three test specimens exhibited shear type motion during failures that occurred in the tile near the tile/strain-isolator-pad bond-line. A dynamic instability is described which has large in-plane motion at a frequency one-half that of the nominal driving frequency. Analysis shows that this phenomenon is a parametric response.

Banks of lights dry tiles on Atlantis

NASA Technical Reports Server (NTRS)

2001-01-01

KENNEDY SPACE CENTER, Fla. -- In the Orbiter Processing Facility, a worker points to some of the tiles on orbiter Atlantis that are being dried by clusters of 200-300 watt heat lamps. Significant rainstorms during the orbiter'''s turnaround for a ferry flight home from Edwards Air Force Base, Calif., caused a moisture problem. The tiles are part of the Thermal Protection System used on orbiters for extreme temperatures encountered during landing. Engineers are evaluating the current procedures to assure the tiles are in a safe and flight-ready condition.

Biosynthesis of Diterpenoids in Tripterygium Adventitious Root Cultures1[OPEN

PubMed Central

Inabuy, Fainmarinat S.; Fischedick, Justin T.; Lange, Iris; Xu, Meimei

2017-01-01

Adventitious root cultures were developed from Tripterygium regelii, and growth conditions were optimized for the abundant production of diterpenoids, which can be collected directly from the medium. An analysis of publicly available transcriptome data sets collected with T. regelii roots and root cultures indicated the presence of a large gene family (with 20 members) for terpene synthases (TPSs). Nine candidate diterpene synthase genes were selected for follow-up functional evaluation, of which two belonged to the TPS-c, three to the TPS-e/f, and four to the TPS-b subfamilies. These genes were characterized by heterologous expression in a modular metabolic engineering system in Escherichia coli. Members of the TPS-c subfamily were characterized as copalyl diphosphate (diterpene) synthases, and those belonging to the TPS-e/f subfamily catalyzed the formation of precursors of kaurane diterpenoids. The TPS-b subfamily encompassed genes coding for enzymes involved in abietane diterpenoid biosynthesis and others with activities as monoterpene synthases. The structural characterization of diterpenoids accumulating in the medium of T. regelii adventitious root cultures, facilitated by searching the Spektraris online spectral database, enabled us to formulate a biosynthetic pathway for the biosynthesis of triptolide, a diterpenoid with pharmaceutical potential. Considering the significant enrichment of diterpenoids in the culture medium, fast-growing adventitious root cultures may hold promise as a sustainable resource for the large-scale production of triptolide. PMID:28751314

SU-F-T-240: EPID-Based Quality Assurance for Dosimetric Credentialing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miri, N; Lehmann, J; Vial, P

Purpose: We propose a novel dosimetric audit method for clinical trials using EPID measurements at each center and a standardized EPID to dose conversion algorithm. The aim of this work is to investigate the applicability of the EPID method to different linear accelerator, EPID and treatment planning system (TPS) combinations. Methods: Combination of delivery and planning systems were three Varian linacs including one Pinnacle and two Eclipse TPS and, two ELEKTA linacs including one Pinnacle and one Monaco TPS. All Varian linacs had the same EPID structure and similarly for the ELEKTA linacs. Initially, dose response of the EPIDs wasmore » investigated by acquiring integrated pixel value (IPV) of the central area of 10 cm2 images versus MUs, 5-400 MU. Then, the EPID to dose conversion was investigated for different system combinations. Square field size images, 2, 3, 4, 6, 10, 15, 20, 25 cm2 acquired by all systems were converted to dose at isocenter of a virtual flat phantom then the dose was compared to the corresponding TPS dose. Results: All EPIDs showed a relatively linear behavior versus MU except at low MUs which showed irregularities probably due to initial inaccuracies of irradiation. Furthermore, for all the EPID models, the model predicted TPS dose with a mean dose difference percentage of 1.3. However the model showed a few inaccuracies for ELEKTA EPID images at field sizes larger than 20 cm2. Conclusion: The EPIDs demonstrated similar behavior versus MU and the model was relatively accurate for all the systems. Therefore, the model could be employed as a global dosimetric method to audit clinical trials. Funding has been provided from Department of Radiation Oncology, TROG Cancer Research and the University of Newcastle. Narges Miri is a recipient of a University of Newcastle postgraduate scholarship.« less

Predicted and tested performance of durable TPS

NASA Technical Reports Server (NTRS)

Shideler, John L.

1992-01-01

The development of thermal protection systems (TPS) for aerospace vehicles involves combining material selection, concept design, and verification tests to evaluate the effectiveness of the system. The present paper reviews verification tests of two metallic and one carbon-carbon thermal protection system. The test conditions are, in general, representative of Space Shuttle design flight conditions which may be more or less severe than conditions required for future space transportation systems. The results of this study are intended to help establish a preliminary data base from which the designers of future entry vehicles can evaluate the applicability of future concepts to their vehicles.

A Collaborative Analysis Tool for Thermal Protection Systems for Single Stage to Orbit Launch Vehicles

NASA Technical Reports Server (NTRS)

Alexander, Reginald A.; Stanley, Thomas Troy

1999-01-01

Presented is a design tool and process that connects several disciplines which are needed in the complex and integrated design of high performance reusable single stage to orbit (SSTO) vehicles. Every system is linked to every other system and in the case of SSTO vehicles with air breathing propulsion, which is currently being studied by the National Aeronautics and Space Administration (NASA); the thermal protection system (TPS) is linked directly to almost every major system. The propulsion system pushes the vehicle to velocities on the order of 15 times the speed of sound in the atmosphere before pulling up to go to orbit which results high temperatures on the external surfaces of the vehicle. Thermal protection systems to maintain the structural integrity of the vehicle must be able to mitigate the heat transfer to the structure and be lightweight. Herein lies the interdependency, in that as the vehicle's speed increases, the TPS requirements are increased. And as TPS masses increase the effect on the propulsion system and all other systems is compounded. To adequately determine insulation masses for a vehicle such as the one described above, the aeroheating loads must be calculated and the TPS thicknesses must be calculated for the entire vehicle. To accomplish this an ascent or reentry trajectory is obtained using the computer code Program to Optimize Simulated Trajectories (POST). The trajectory is then used to calculate the convective heat rates on several locations on the vehicles using the Miniature Version of the JA70 Aerodynamic Heating Computer Program (MINIVER). Once the heat rates are defined for each body point on the vehicle, then insulation thicknesses that are required to maintain the vehicle within structural limits are calculated using Systems Improved Numerical Differencing Analyzer (SINDA) models. If the TPS masses are too heavy for the performance of the vehicle the process may be repeated altering the trajectory or some other input to reduce the TPS mass. The problem described is an example of the need for collaborative design and analysis. Analysis tools are being developed to facilitate these collaborative efforts. RECIPE is a cross-platform application capable of hosting a number of engineers and designers across the Internet for distributed and collaborative engineering environments. Such integrated system design environments allow for collaborative team design analysis for performing individual or reduced team studies. The analysis tools mentioned earlier are commonly run on different platforms and are usually run by different people. To facilitate the larger number of potential runs that may need to be made, RECIPE connects the computer codes that calculate the trajectory data, heat rate data, and TPS masses so that the output from each tool is easily transferred to the model input files that need it. This methodology is being applied to solve launch vehicle thermal design problems to shorten the design cycle, and enable the project team to evaluate design options. Results will be presented indicating the effectiveness of this as a collaborative design tool.

High-Temperature Structures, Adhesives, and Advanced Thermal Protection Materials for Next-Generation Aeroshell Design

NASA Technical Reports Server (NTRS)

Collins, Timothy J.; Congdon, William M.; Smeltzer, Stanley S.; Whitley, Karen S.

2005-01-01

The next generation of planetary exploration vehicles will rely heavily on robust aero-assist technologies, especially those that include aerocapture. This paper provides an overview of an ongoing development program, led by NASA Langley Research Center (LaRC) and aimed at introducing high-temperature structures, adhesives, and advanced thermal protection system (TPS) materials into the aeroshell design process. The purpose of this work is to demonstrate TPS materials that can withstand the higher heating rates of NASA's next generation planetary missions, and to validate high-temperature structures and adhesives that can reduce required TPS thickness and total aeroshell mass, thus allowing for larger science payloads. The effort described consists of parallel work in several advanced aeroshell technology areas. The areas of work include high-temperature adhesives, high-temperature composite materials, advanced ablator (TPS) materials, sub-scale demonstration test articles, and aeroshell modeling and analysis. The status of screening test results for a broad selection of available higher-temperature adhesives is presented. It appears that at least one (and perhaps a few) adhesives have working temperatures ranging from 315-400 C (600-750 F), and are suitable for TPS-to-structure bondline temperatures that are significantly above the traditional allowable of 250 C (482 F). The status of mechanical testing of advanced high-temperature composite materials is also summarized. To date, these tests indicate the potential for good material performance at temperatures of at least 600 F. Application of these materials and adhesives to aeroshell systems that incorporate advanced TPS materials may reduce aeroshell TPS mass by 15% - 30%. A brief outline is given of work scheduled for completion in 2006 that will include fabrication and testing of large panels and subscale aeroshell test articles at the Solar-Tower Test Facility located at Kirtland AFB and operated by Sandia National Laboratories. These tests are designed to validate aeroshell manufacturability using advanced material systems, and to demonstrate the maintenance of bondline integrity at realistically high temperatures and heating rates. Finally, a status is given of ongoing aeroshell modeling and analysis efforts which will be used to correlate with experimental testing, and to provide a reliable means of extrapolating to performance under actual flight conditions. The modeling and analysis effort includes a parallel series of experimental tests to determine TSP thermal expansion and other mechanical properties which are required for input to the analysis models.

SU-E-J-199: A Software Tool for Quality Assurance of Online Replanning with MR-Linac

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, G; Ahunbay, E; Li, X

2015-06-15

Purpose: To develop a quality assurance software tool, ArtQA, capable of automatically checking radiation treatment plan parameters, verifying plan data transfer from treatment planning system (TPS) to record and verify (R&V) system, performing a secondary MU calculation considering the effect of magnetic field from MR-Linac, and verifying the delivery and plan consistency, for online replanning. Methods: ArtQA was developed by creating interfaces to TPS (e.g., Monaco, Elekta), R&V system (Mosaiq, Elekta), and secondary MU calculation system. The tool obtains plan parameters from the TPS via direct file reading, and retrieves plan data both transferred from TPS and recorded during themore » actual delivery in the R&V system database via open database connectivity and structured query language. By comparing beam/plan datasets in different systems, ArtQA detects and outputs discrepancies between TPS, R&V system and secondary MU calculation system, and delivery. To consider the effect of 1.5T transverse magnetic field from MR-Linac in the secondary MU calculation, a method based on modified Clarkson integration algorithm was developed and tested for a series of clinical situations. Results: ArtQA is capable of automatically checking plan integrity and logic consistency, detecting plan data transfer errors, performing secondary MU calculations with or without a transverse magnetic field, and verifying treatment delivery. The tool is efficient and effective for pre- and post-treatment QA checks of all available treatment parameters that may be impractical with the commonly-used visual inspection. Conclusion: The software tool ArtQA can be used for quick and automatic pre- and post-treatment QA check, eliminating human error associated with visual inspection. While this tool is developed for online replanning to be used on MR-Linac, where the QA needs to be performed rapidly as the patient is lying on the table waiting for the treatment, ArtQA can be used as a general QA tool in radiation oncology practice. This work is partially supported by Elekta Inc.« less

Performance of a mullite reusable surface insulation system in a hypersonic stream

NASA Technical Reports Server (NTRS)

Hunt, L. R.

1976-01-01

The thermal and structural performance of a large panel of mullite reusable surface insulation (RSI) tiles was determined by a series of aerothermal tests in the Langley 8-foot high-temperature structures tunnel. The test panel was designed to represent a portion of the surface structure on a space shuttle orbiter fuselage along a 1,150 K isotherm with the mullite tile system bonded directly to the primary structure. Aerothermal tests were conducted at a free-stream Mach number of 6.7, a total temperature of 1,880 K, a unit Reynolds number of 4.6 million per meter, and dynamic pressure of 62 kPa. The thermal response of the mullite tile was as predicted, and the bond-line temperature did not exceed the design level of 570 K during a typical entry-heat cycle. Geometric irregularities of the tile gaps affected the tile edge temperatures when exposed to hypersonic flow. The tile coating demonstrated good toughness to particle impacts, but the coating cracked and flaked with thermal cycles. The gap filler of woven silica fibers appeared to hinder flow penetration into the gaps and withstood the flow shear of the present tests.

An efficient method to determine double Gaussian fluence parameters in the eclipse™ proton pencil beam model.

PubMed

Shen, Jiajian; Liu, Wei; Stoker, Joshua; Ding, Xiaoning; Anand, Aman; Hu, Yanle; Herman, Michael G; Bues, Martin

2016-12-01

To find an efficient method to configure the proton fluence for a commercial proton pencil beam scanning (PBS) treatment planning system (TPS). An in-water dose kernel was developed to mimic the dose kernel of the pencil beam convolution superposition algorithm, which is part of the commercial proton beam therapy planning software, eclipse™ (Varian Medical Systems, Palo Alto, CA). The field size factor (FSF) was calculated based on the spot profile reconstructed by the in-house dose kernel. The workflow of using FSFs to find the desirable proton fluence is presented. The in-house derived spot profile and FSF were validated by a direct comparison with those calculated by the eclipse TPS. The validation included 420 comparisons of the FSFs from 14 proton energies, various field sizes from 2 to 20 cm and various depths from 20% to 80% of proton range. The relative in-water lateral profiles between the in-house calculation and the eclipse TPS agree very well even at the level of 10 -4 . The FSFs between the in-house calculation and the eclipse TPS also agree well. The maximum deviation is within 0.5%, and the standard deviation is less than 0.1%. The authors' method significantly reduced the time to find the desirable proton fluences of the clinical energies. The method is extensively validated and can be applied to any proton centers using PBS and the eclipse TPS.

Kinetics of DNA tile dimerization.

PubMed

Jiang, Shuoxing; Yan, Hao; Liu, Yan

2014-06-24

Investigating how individual molecular components interact with one another within DNA nanoarchitectures, both in terms of their spatial and temporal interactions, is fundamentally important for a better understanding of their physical behaviors. This will provide researchers with valuable insight for designing more complex higher-order structures that can be assembled more efficiently. In this report, we examined several spatial factors that affect the kinetics of bivalent, double-helical (DH) tile dimerization, including the orientation and number of sticky ends (SEs), the flexibility of the double helical domains, and the size of the tiles. The rate constants we obtained confirm our hypothesis that increased nucleation opportunities and well-aligned SEs accelerate tile-tile dimerization. Increased flexibility in the tiles causes slower dimerization rates, an effect that can be reversed by introducing restrictions to the tile flexibility. The higher dimerization rates of more rigid tiles results from the opposing effects of higher activation energies and higher pre-exponential factors from the Arrhenius equation, where the pre-exponential factor dominates. We believe that the results presented here will assist in improved implementation of DNA tile based algorithmic self-assembly, DNA based molecular robotics, and other specific nucleic acid systems, and will provide guidance to design and assembly processes to improve overall yield and efficiency.

The rice terpene synthase gene OsTPS19 functions as an (S)-limonene synthase in planta, and its overexpression leads to enhanced resistance to the blast fungus Magnaporthe oryzae.

PubMed

Chen, Xujun; Chen, Hao; Yuan, Joshua S; Köllner, Tobias G; Chen, Yuying; Guo, Yufen; Zhuang, Xiaofeng; Chen, Xinlu; Zhang, Yong-Jun; Fu, Jianyu; Nebenführ, Andreas; Guo, Zejian; Chen, Feng

2018-03-06

Rice blast disease, caused by the fungus Magnaporthe oryzae, is the most devastating disease of rice. In our ongoing characterization of the defence mechanisms of rice plants against M. oryzae, a terpene synthase gene OsTPS19 was identified as a candidate defence gene. Here, we report the functional characterization of OsTPS19, which is up-regulated by M. oryzae infection. Overexpression of OsTPS19 in rice plants enhanced resistance against M. oryzae, while OsTPS19 RNAi lines were more susceptible to the pathogen. Metabolic analysis revealed that the production of a monoterpene (S)-limonene was increased and decreased in OsTPS19 overexpression and RNAi lines, respectively, suggesting that OsTPS19 functions as a limonene synthase in planta. This notion was further supported by in vitro enzyme assays with recombinant OsTPS19, in which OsTPS19 had both sesquiterpene activity and monoterpene synthase activity, with limonene as a major product. Furthermore, in a subcellular localization experiment, OsTPS19 was localized in plastids. OsTPS19 has a highly homologous paralog, OsTPS20, which likely resulted from a recent gene duplication event. We found that the variation in OsTPS19 and OsTPS20 enzyme activities was determined by a single amino acid in the active site cavity. The expression of OsTPS20 was not affected by M. oryzae infection. This indicates functional divergence of OsTPS19 and OsTPS20. Lastly, (S)-limonene inhibited the germination of M. oryzae spores in vitro. OsTPS19 was determined to function as an (S)-limonene synthase in rice and plays a role in defence against M. oryzae, at least partly, by inhibiting spore germination. © 2018 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

75 FR 6700 - Notice of Proposed Withdrawal Extension and Opportunity for Public Meeting; Alaska

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-10

.... 6892 for an additional 20-year period. This order withdrew approximately 473 acres of National Forest... Creek Recreation Area. This withdrawal comprises approximately 473 acres of National Forest System land located in the Chugach National Forest, within Tps. 7 and 8 N., R. 1 E., and Tps. 8 and 9 N., R. 1 W...

Dosimetry audit simulation of treatment planning system in multicenters radiotherapy

NASA Astrophysics Data System (ADS)

Kasmuri, S.; Pawiro, S. A.

2017-07-01

Treatment Planning System (TPS) is an important modality that determines radiotherapy outcome. TPS requires input data obtained through commissioning and the potentially error occurred. Error in this stage may result in the systematic error. The aim of this study to verify the TPS dosimetry to know deviation range between calculated and measurement dose. This study used CIRS phantom 002LFC representing the human thorax and simulated all external beam radiotherapy stages. The phantom was scanned using CT Scanner and planned 8 test cases that were similar to those in clinical practice situation were made, tested in four radiotherapy centers. Dose measurement using 0.6 cc ionization chamber. The results of this study showed that generally, deviation of all test cases in four centers was within agreement criteria with average deviation about -0.17±1.59 %, -1.64±1.92 %, 0.34±1.34 % and 0.13±1.81 %. The conclusion of this study was all TPS involved in this study showed good performance. The superposition algorithm showed rather poor performance than either analytic anisotropic algorithm (AAA) and convolution algorithm with average deviation about -1.64±1.92 %, -0.17±1.59 % and -0.27±1.51 % respectively.

Aerothermal Testing of Woven TPS Ablative Materials

NASA Technical Reports Server (NTRS)

Stackpoole, Mairead; Feldman, Jay; Olson, Michael; Venkatapathy, Ethiraj

2012-01-01

Woven Thermal Protection Systems (WTPS) is a new TPS concept that is funded by NASAs Office of the Chief Technologist (OCT) Game Changing Division. The WTPS project demonstrates the potential for manufacturing a variety of TPS materials capable of wide ranging performances demanded by a spectrum of solar system exploration missions. Currently, missions anticipated to encounter heat fluxes in the range of 1500 4000 Watts per square centimeter are limited to using one proven material fully dense Carbon Phenolic. However, fully dense carbon phenolic is only mass efficient at heat fluxes greater than 4000 Watts per square centimeter, and current mission designs suffer this mass inefficiency for lack of an alternative mid-density TPS. WTPS not only bridges this gap but also offers a replacement for carbon phenolic, which itself requires a significant and costly redevelopment effort to re-establish its capability for use in the high heat flux missions recently prioritized in the NRC Decadal survey, including probe missions to Venus, Saturn and Neptune. This poster will summarize some recent arc jet testing to evaluate the performance of WTPS. Both mid density and fully dense WTPS test results will be presented and results compared to heritage carbon phenolic where applicable.

Assessment of undiscovered conventional oil and gas resources of the Western Canada Sedimentary Basin, Canada, 2012

USGS Publications Warehouse

Higley, Debra K.

2013-01-01

The U.S. Geological Survey recently completed a geoscience-based assessment of undiscovered oil and gas resources of provinces within the Western Canada Sedimentary Basin. The Western Canada Sedimentary Basin primarily comprises the (1) Alberta Basin Province of Alberta, eastern British Columbia, and the southwestern Northwest Territories; (2) the Williston Basin Province of Saskatchewan, southeastern Alberta, and southern Manitoba; and (3) the Rocky Mountain Deformed Belt Province of western Alberta and eastern British Columbia. This report is part of the U.S. Geological Survey World Petroleum Resources Project assessment of priority geologic provinces of the world. The assessment was based on geoscience elements that define a total petroleum system (TPS) and associated assessment unit(s). These elements include petroleum source rocks (geochemical properties and petroleum generation, migration, and accumulation), reservoir description (reservoir presence, type, and quality), and petroleum traps (trap and seal types, and timing of trap and seal formation relative to petroleum migration). Using this framework, the Elk Point-Woodbend Composite TPS, Exshaw-Fernie-Mannville Composite TPS, and Middle through Upper Cretaceous Composite TPS were defined, and four conventional assessment units within the total petroleum systems were quantitatively assessed for undiscovered resources in the Western Canada Sedimentary Basin.